Well they dropped 5 valve long ago even in today's Moto GP prototypes. Ducati is better known for getting the most power from a set capacity in recent racing.
What's funny? Honda took the intercept v4 750 put the Cylinders from the 1100 v4 on it said it was 1003cc they said it made over 150hp how fast it was. They went to Daytona 1983 Kenny Roberts, on a Yamaha YZR 500 two-stroke and whipped that Honda 1000cc v4 🤣🤣🤣
I had a 1985 Canadian FZX 750 (fazer) until 2001, with it’s milder cam than the FX 750 it had lots of torque, at one point I used it to tow a late 70’s Volvo 240 wagon about half a kilometre, my friend had a problem hear his home, with him pushing the driver side door and a 2 or 3 degree downwards slope to get started the bike was able to pull that 1.5 ton car back to his place on the first try without damaging the clutch. At some other time I told some friends I was sure it could start in 6th gear with 2 on it with no problem, one of them started arguing that was impossible, ‘grab your helmet Jack’, 5 minutes later we were back at his place where he confirmed to his roommate and his brother that it went so well it was mind boggling.
Cool I Used to have an 1982 Yamaha XJ750 maximum. The guy who had it before me Use it to pull up Volkswagen about 20 miles. when I got it I pulled a 1981 Honda CB750 it had a Windjammer fairing on from Atlanta Georgia to Phenix city, Alabama 117 miles. I was hit 110 Yamaha was in front of a Honda as Usual.🤣🤣🤣
Going beyond 5 valves has been demonstrated to increase Valve Shrouding in the Cylinder . The 8 valve Honda NR series , was really an altered 32 vale V-8
honda was simply smarter than yamaha and realized more valves per cylinder only works if you change the shape of the cylinder, yamaha was stubborn and stuck with a round shape and wasted their time, now they use 4 valve again
@@bluestripes1. Yeah ? So how Reliable were the NR series Engines ? Answer is : They WEREN'T . So , you were saying ? Honda DID have a good idea , but the Engineering Problems and Hurdles were always going to be a " Huge Ask " and proved insurmountable in the end . Yamaha DO still use 5 valve configuration , and sell it to others as well .
@@bluestripes1 As the OP stated , the Honda NR series was just a 4 valve per cylinder V8 with pairs of siamesed cylinders - designed to get around the 4 cylinder limit imposed at the time. It wasn't really an innovation. If it was , there would have been be more than just a token production model.
Imagine the drag on the systems that forced all those valve springs open. Of course, each spring would have less resistance due to smaller valves, but still.
Loved my FZR1000! My favorite engine in all of motorcycling. Yamaha really hit the mark with a great design as the valve adjustment intervals were at 26,000 miles. I put close to 100,000 miles on that bike and only made one valve adjustment. These were hard miles too as this bike was a Sunday morning jailhouse special. When I sold her she was still running strong, not smoking or leaking. Wish I had her back.
@@johncunningham4820 jeez u sound fun at parties mate,😂😂😂 ok I lemme correct myself. it be cool to see a 5 valve engine, with triflux inspired valve layout on the cylinder head. Happy now Karen 👍🏼
@@_Y.J . So then , clearly YOU don't take well to being called out on speaking Total Fucking Rubbish . 5 valve head designs only JUST justify themselves in volumetric efficiency vs mechanical loss over 4 valve designs by a small margin . Sufficient to be worthwhile . Diesel Engine (heavy-duty types ) also tried 5 & 6 valve designs and ran into the Same Issues as Petrol/Gasoline Engines . Too much valve shrouding . Making 90% of the Combustion Chamber into Valve area actually didn't help , and the Mechanical losses DRIVING all that extra complexity , and hence , reduced reliability and increased maintenance , was actually to ZERO net gains .
@@johncunningham4820 mate read the top comment u mong, I never said anything to do with gains, quit whining with ya long paragraphs that no one cares for, take that stick out ya backside and go outside for the first time, u clearly been stuck in ya shed for 50+ years, I never said anything about gains so clearly u can't read 😂😂😂
2 valves introduce swirl, 4 valves give the charge tumble. Any more than that and the fluid dynamics get wierd. Valentino Rossi prefered the 4 valve arrangement motogp engine which is why Yamaha stopped using 5 valves. Yamaha's brilliance in engineering is something I have always admired but as a mechanic it usually means more difficult repairs and Yamaha is notorious for not keeping stock of previous year models parts. I own all 3 other Japanese brand bikes due to parts availability. My 1st 4 bikes where Yamahas, I loved all of them!
we had some success messing with the 5v heads, but changing the valve timing on only the center intake valve. Found a lot of torque from idle to about 4500, then signed off. If there was a variable cam timing available for the 5v heads, I think it could be phenominal, but in those days VVT was not really thought about much. We did it by having a cam grinding company regrind the cam (DOHC, so it had individual lobes), and later did a SOHC 660cc 5v with the same type deal but we had to re-engineer the rocker arms to work. Had we had more time (and especially money & manpower) I think we could have improved on the design even further. Like the prior, all of it was scrapped, as it was just some of us gearheads in a garage trying to make stuff work "better"-and when one of "us" (them) decided to stay out too late & party, it kind of got old having to work around their bad habits which caused some arguements.
my fazer 1000 was a 20v engine, and without its exup it felt super gutless, but the power band was nice after 7k rpm. Sounded super smooth and happy to be up in that rev range. The head never failed on that bike with 70k miles, but their transmissions didn't live long to tell the tale.
Even the 5 valve was a flop- while it made a great torque curve, it was down on horsepower. It's the old hemi curse; maximum breathing alone isn't enough without proper combustion. After that, everyone settled on the 'pentroof' 4 valve style as the best compromise.
4 valves is just the magic number for a round combustion chamber, it provides the biggest gas flow without making the valve train overcomplicated. Specialty designed exhaust improves gas scavenging and intake compressor shoves more air into the engine, so that efficiently solves both issues that large number of valves were meant to solve. The whole reason anyone even went the route of making more valves over just using a turbo is the arbitrary racing rules and restrictions that they had to work around.
Recent new design have proven 5 valve gives greastest power and torgue combined with a state of the art combustion chamber designed by Patric Miller Engeneering
Ive been aware of the 6 and 7 valve heads for a while. But Ive never seen pics of the ports for those heads. Im very interested in the port design for those heads.
While on the topic of Yamaha. I recommend falling down the rabbit hole of their snowmobiles. On the cutting edge of engine technology there too. I appreciate every single one of your videos. Keep up the great work!
habe gerade eine 750 , Yamaha , Baujahr 1986 überholt und war ganz erstaunt dass der Motor fünf Ventile hat und in dieser Zeit war Yamaha der Konkurrenz voraus.
did many a valve adjustment on the 5v Yamaha's. And a bunch of 4v Yamaha's. And a ton of 2v and 3v as well. Yes they had a 3v (50cc). I don't miss it but looks like I may get back into it again, 4 year break from working on Japanese stuff and the boss wants to buy a Yamaha dealership. doing the valves on a Genesis takes patience, concentration, and a steady but methodic approach. Also requires some good organizational skills to keep up with shims and such. Ain't all that hard if you keep up with everything. Time consuming though!
While the 7 valve head seems too complicated to me and everything above 4 or 5 valves on a smaller engine doesn't bring benefits, the use of 6 valve heads in production engines was real. The Maybach MD650-655 and 870 diesel engines for marine and railway traction usage had 6 valve heads, these were operated by only two overhead cam shafts, one of these shafts also operated the mechanical pump/injector units on each cylinder. It would be interesting do do a topic on these engines as they were very advanced for the early 1950s when they were developed, I worked on one of them and setting all those valves and injectors is a very intricate job.
Didn't maserati try to make a 6 valve and relised that 5 valves was the most efficient design and since then its been accepted beyond 5 valves has no benefit
One nice thing about 5 valve heads on Yamahas, the smaller intakes hold lash adjustment for a long time. They do like to be fueled on on the richer side, and a bit more spark advance than a 4 valve head, as they aren't as efficient a combustion chamber shape and as a result don't burn as fast as a 4 valve head. I had a nicely Ivan's Performance tuned '06 FZ1, it was a liquid revs kind of beast on the cam from 7K to the 13K rev limiter I saw Jesus quite a few times on it 😆
Err no not quite , the 5 valve head was better at the time but eventually materials / development caught up and allowed a four valve design to match the 5 valve head .
@@Dwainpipe21 Not sure what materials development altered physics, but gas flow through a poppet valve is tied closer to total periphery than area.... until the valves crowd each other and the periphery effects clash. The breathing advantage of a 5-valve was always marginal, if it existed, and the cost (in every meaning) was high. Maybe worth if from the marketing side, but when that petered out, goner.
@@ElsinoreRacer I read when they went back to 4 valve design it was because 5 valves allow more revs better control of the valves as the valves are lighter ( smaller ) but with modern materials a 4 valve head is just as good .
Nothing like a good Micron exhaust pipe back in the day (before the company went away). Nice deep tuned tones. Everything today is raspy loud obnoxious and expensive when it comes to exhausts.
@@mikerieck306 They were pretty common, not sure what caused that company to stop producing. I liked their rainbow colored heat treatments. Mainly, they were a simple oval or round shape at varying lengths and the tone they produced was very complimentary to inline-4 cylinders. Today exhausts cost a LOT more, offer less reduction of loudness, offer a much worse tone, and have far more expensive and complicated materials and shapes.
How many valves do you want? As many as possible. If you have to rebuild one I feel like it would be a real pain. But I trust in Yamaha to make a lot of good things
I find this interesting. The most common 5V head I encouter is in the VW 1.8T in the B5 Passat and MKIV GTI. Once GDI was introduced, it seems like there wasn't a way to build a 5V engine. Perhaps 5V GDI engines can be build but it was not worth it.
Freevalve technology could make this almost viable. What I am really hoping for is that freevalve technology will revive the 5 valve per piston design.
I needed all the power i could muster back in the 90's racing superbike in the AMA FUSA and WERA and Suzuki IMHO had the best potential for me.....i was 6'4" and 250 with my leathers...lol
Like to believe that had Yamaha been able to diversify as a low-volume sportscar and kei car producer (e.g. 1961 Yamaha YX30 prototype and a 1958 kei car project) vaguely similar to Lotus (and like Lotus its engineering department working with other carmakers), that 5-valves and maybe bi-turbos would be its USP. Would they have been crazy enough though to try and develop 6/7-valves for cars like Maserati did with a 6-valve engine in the 1980s?
@@jameshatton4211 I was just trying to Educate , in the event you Didn't know . Not belittle you . Actually , Harmonics yes , but FLOW DYNAMICS is the other thing . A Crisp sound is a byproduct of That . Also LFA is a V-10 . They ALL sound awesome anyway .
Why not build a engine with two pistons and Sharing the combustion chamber, similar to a split single, only using 4 stroke it will allow more valve area than piston area, use two rod journals and minimum space between pistons. Something like the oval piston engine only more reliable and easy to build. Say a 125 cc engine using two 50 mm bores with four, 20 mm intake valves and four 18mm exhaust valves, or 26/22 mm intake/exhaust. The combustion chamber width of two 50mm bores, would be about 110-120 mm say 50 x 115 mm the flow should be off the charts and cam timing and exact piston timing can be "adjusted" to induce swirl by opening on pistons valve just before the other. And closing earlier, with the othercloding later. Causing swirl in the cylinder. Mixing the air fuel. Keeping the port velocity high. Making power even better imagine two cranks four pistons, with single head and chamber having valve area larger than each piston say 50mm bores, with 3x 38 mm valves on the intake and 3x 34mm exhaust valves with 4 plugs firing at once. It Would be interesting to see if nothing else!
You would think the 6 valve would be arranged like the 7 valve with the plug in the middle and indexed towards with intake valve. Or running a twin ground strap plug.
People forget the much lauded Nissan RB26 "is also" a Yamaha developed motor & all this because Toyota engineers branched into Yamaha from what predated even TRD
@@VisioRacer yup Volvo & Ford are also among those that come to mind, but yeah, Donut Media did a video on how they started from a group of Toyota's Engineers who were responsible for racing & engine development. I'm glad I have a few of their engines including a couple 5 Valvers, wish they'd kept them going
@@skylinefever Albrecht Goertz of Yamaha is responsible for his working with Nissan, even though the official partnership with Nissan feel thru his designs are still reflected in the L series, RB series & the Nissan Fairlady which all stem from the 2000GT project which originally was meant for Nissan Ironically Nissan thought it not financially viable so Goertz took the project to conservative Toyota & we got Japan's first supercar the Toyota 2000GT, but if you look up Nissan 2000GT you will find what resembles a Corvette Stingray front with a Fairlady Z body Under it's hood was the R&D that led to the L series which if you know is what evolved to the RB, though the RB is closer to the original Yamaha R&D. The story was supposedly that Nissan didn't need the partnership, but if you look at what came of it Nissan clearly reused the Yamaha derived work The difference is, it's Nissan take on Yamaha R&D that was developed for them but doesn't credit, which in Japan is legal, it's how the Yamaha derived Toyota 2ZZ basically has iVTEC before Honda when Honda only had VTEC before Toyota's VVTLi, they both took each other's ideas TLDR; reason most don't know Yamaha's designs lead to the RB is because within Japan you can take others ideas so long as you add your own twist or pay royalties a few years. Yamaha for example doesn't get to gatekeep who uses their research(even though in this case it was for Nissan), it's part of why Japan has a leg up on innovation, because they have to constantly innovate something new to stay relevant against their own R&D, it's also why they can't sue Nissan, just like how litigious Nintendo can't go against PalWorld since their IP is both Japan based
5v per cylinder is best. The valves begin to shroud each other and block the flow of each other the greater number after this. 3 intake valves and 2 exhaust valves. Basicaly the act of pushing the valve into the cylinder causes you to lose more volume so the displaced volume of hte valve also the smaller and more numberous the value the smaller the port to flow gas through. Also the extreme at the other end, is bad, so many tiny valves causes the skin friction drag to increase at a much higher rate than a small series of larger ports. 5V per cylinder is the best.
Yamaha: "We're worried about the power limits of 2-stroke engines." Detroit: LOL... Thou doest worry too much over nothing. Wartsila: That table you are having your crisis at is the top of one of my pistons.
Why no mention of the legendary 1.8t VW engine? Best bang for buck for regular blokes. Those 4age engines are completely pointless when even simple unknown engine costs 1500+eur
The 750 yamaha 5 valve had poor combustion chambers when the compression ratio was raised for racing since the chamber became the valve pockets and quench area. As a result it could not compete with a 4 valve except with regular lower octane street gas in both engines.
The only other account I can remember of an engine with more than 5 valves is the V12 in Speed Racer’s Mach 5 from what I remember looking its specs up out of curiosity
I remember reading a really short article on an italian motorcycle magazine back in the 90s! I did not completely understand what that meant back then, as I was just a petrolhead cub, but I remember I thought "damn, that's some crazy engineering!", as I still think it is... It's sad that most of the R&D craziness of the past has been stopped because of cost and pollution reasons, now every new model might be cleaner than the previous one, but is also less exciting...
NR pistons are not oval, are oblong. I have been correcting this statement since the NR750 was born but people still keep using the same erroneus shape description. Now think for a moment and picture an oval shaped piston section... Cartoonish.
Oh my...the first 5valve engines were somewhat a nightmare once you get valve seat recession, and to a lesser extent, stretched and deformed valves. Until the R1 the cylinder heads had this girdle-like camshaft journal that made work complicated. When better valvetrain metals had been available it made the switch back to 4 valves quite easy, uneven combustion was one of the issues with higher strung 5 valve engines. Can't drive up the compression ratio as high. Still it was very nice at its time!
Seus videos devem ser ótimos.mas não entendo nada de inglês. Se você colocar algum tipo de tradução em vários idiomas seria de grande ajuda.e conseguiria mais inscrições.
5 valves per cylinder seems to be the perfect level of sophistication. It's power advantages are already questionable compared to 4valves setup and of course fuel consumption increases massively. Still it's cool. 7valves per cylinder is just ridiculous, too complex and too much added friction in the valvetrain which lead too to much parasitic loses.
All these multi valve engines, and a BIG American V8 pushrod engine can rev to 9,000 rpm (11,000 for the Ilmor Indy car), if you scaled down the big V8 you could increase the revs corresponding.
i would live to see a "single valve" head with a singular massive valve per cylinder but with a couple of rotary valves above to actually controll the intake and exhausr
A diesel doesn't even need the rotary valves, you can just not have an exhaust or inlet manifold. Packard made a diesel radial like that, the DR-980. There was also a rotary (spinning radial engine, not the dorito type rotary) called the gnome monosoupape that worked a similar way, but being a spark ignition engine it needed a secondary set of inlet ports at the bottom of the cylinder to get fuel in.
Correction : the Volvo B8444S engine is actually built and designed by Yamaha to volvos specs. Volvo had engine bays designed for 4-bangers and 5-pots but needed a more powerful engine for their xc90 and s80 passenger cars for the american market. I guess someone told volvo engineers that americans wont buy their swedish car unless there is a v8 under the hood or something. Anyway, after this went sideways and the americans didn't really like the v8 volvos, Yamaha decided that since they had built such a crazy small v8, they'd just turn the heads upside down into a hot-v configuration, tilt it on it's side, slap a shaft and a propeller into it and call it a day. Thus the yamaha v8 outboards were born.
More valves than there are girls available for Dipper to sleep with (...is Tambry included as well?) Edit: Also that Volvo V8 at the end sounds *amazing* Edit 2: Right, about that whole "Dipper Pines' Wives" schtick: I counted 3 girls (Mabel, Wendy, Pacifica) plus Bill Cipher and Stanley Pines, but I omitted those 'cause Bill and Stan are guys and Dipper's a guy too so that makes it gay, not straight. So Yamaha made an engine with more valves than the number of Dipper's potential wives. *And no, Tambry isn't anywhere on that list* Edit 3: Even *if* we factor in Billdip and Stan x Dipper, that still amounts to 5 compared to 7. So yeah, more valves than there are girls *and* guys available for Dipper to sleep with
Didn't maserati try to make a 6 valve and relised that 5 valves was the most efficient design and since then its been accepted beyond 5 valves has no benefit
biblically accurate cylinder head
Approaching the bike with feeler gauges in hand and you hear a booming voice: "BE NOT AFRAID"
be not afraid…
got dammit you beat me to it
@@Oddman1980🤣🤣
@@Oddman1980Just don't mix the valve shims up😂
Yamaha is and will always be the greatest head designer
I always found it interesting how they built a DOHC head for a Ford OHV block.
@@skylinefever there are a bunch of pretty impressive cars that Yamaha made heads for. The Toyota LFA is another..
Vw 1.8t 20v is also yamaha design. 🎉
Well they dropped 5 valve long ago even in today's Moto GP prototypes.
Ducati is better known for getting the most power from a set capacity in recent racing.
Yamaha (and cosworth, we won't forget about them) have proven being the past and current greatest
Journo: How many valves does it have?
Yamaha engineer: Yes!
worked in Japan have you? I laugh-spit my beer out when I read that.... well done.
It's OK to be scared Scared.. Yamaha is going to be back in front. 😊
All of them......
What's funny? Honda took the intercept v4 750 put the Cylinders from the 1100 v4 on it said it was 1003cc they said it made over 150hp how fast it was. They went to Daytona 1983 Kenny Roberts, on a Yamaha YZR 500 two-stroke and whipped that Honda 1000cc v4 🤣🤣🤣
I had a 1985 Canadian FZX 750 (fazer) until 2001, with it’s milder cam than the FX 750 it had lots of torque, at one point I used it to tow a late 70’s Volvo 240 wagon about half a kilometre, my friend had a problem hear his home, with him pushing the driver side door and a 2 or 3 degree downwards slope to get started the bike was able to pull that 1.5 ton car back to his place on the first try without damaging the clutch.
At some other time I told some friends I was sure it could start in 6th gear with 2 on it with no problem, one of them started arguing that was impossible, ‘grab your helmet Jack’, 5 minutes later we were back at his place where he confirmed to his roommate and his brother that it went so well it was mind boggling.
Don't care what others think.
Cool I Used to have an 1982 Yamaha XJ750 maximum. The guy who had it before me Use it to pull up Volkswagen about 20 miles. when I got it I pulled a 1981 Honda CB750 it had a Windjammer fairing on from Atlanta Georgia to Phenix city, Alabama 117 miles. I was hit 110 Yamaha was in front of a Honda as Usual.🤣🤣🤣
7 valves seems unnecessarily complicated, but I give big props to Yamaha for doing such experiments.
Going beyond 5 valves has been demonstrated to increase Valve Shrouding in the Cylinder .
The 8 valve Honda NR series , was really an altered 32 vale V-8
honda was simply smarter than yamaha and realized more valves per cylinder only works if you change the shape of the cylinder, yamaha was stubborn and stuck with a round shape and wasted their time, now they use 4 valve again
@@bluestripes1. Yeah ? So how Reliable were the NR series Engines ?
Answer is : They WEREN'T .
So , you were saying ?
Honda DID have a good idea , but the Engineering Problems and Hurdles were always going to be a " Huge Ask " and proved insurmountable in the end .
Yamaha DO still use 5 valve configuration , and sell it to others as well .
@@bluestripes1 As the OP stated , the Honda NR series was just a 4 valve per cylinder V8 with pairs of siamesed cylinders - designed to get around the 4 cylinder limit imposed at the time.
It wasn't really an innovation. If it was , there would have been be more than just a token production model.
Imagine the drag on the systems that forced all those valve springs open. Of course, each spring would have less resistance due to smaller valves, but still.
@@exothermal.sprocket . Exactly . Any Volumetric Gains were Lost again with the added resistance and complexity .
Love the show, I raced a Yamaha 5 valve for years.
Loved my FZR1000! My favorite engine in all of motorcycling. Yamaha really hit the mark with a great design as the valve adjustment intervals were at 26,000 miles. I put close to 100,000 miles on that bike and only made one valve adjustment. These were hard miles too as this bike was a Sunday morning jailhouse special. When I sold her she was still running strong, not smoking or leaking. Wish I had her back.
Best educational engine channel on you tube.
It has been year's and still I am connected to this channel, love from India 🇮🇳🫶
im am deeply sorry for you
My cat loves u too.. free India from RSS!
Gotta love 5 valve engines, they just hit different, a cross flow design would be a headache to design but it id reckon it would rev nicer
WHAT ! ? Both 4 and 5 valve designs ARE crossflow . Basically by definition .
In fact Crossflow has be USUAL since the demise of Side-valve Heads .
@@johncunningham4820 jeez u sound fun at parties mate,😂😂😂 ok I lemme correct myself. it be cool to see a 5 valve engine, with triflux inspired valve layout on the cylinder head. Happy now Karen 👍🏼
@@_Y.J . So then , clearly YOU don't take well to being called out on speaking Total Fucking Rubbish .
5 valve head designs only JUST justify themselves in volumetric efficiency vs mechanical loss over 4 valve designs by a small margin . Sufficient to be worthwhile .
Diesel Engine (heavy-duty types ) also tried 5 & 6 valve designs and ran into the Same Issues as Petrol/Gasoline Engines .
Too much valve shrouding .
Making 90% of the Combustion Chamber into Valve area actually didn't help , and the Mechanical losses DRIVING all that extra complexity , and hence , reduced reliability and increased maintenance , was actually to ZERO net gains .
@@johncunningham4820 mate read the top comment u mong, I never said anything to do with gains, quit whining with ya long paragraphs that no one cares for, take that stick out ya backside and go outside for the first time, u clearly been stuck in ya shed for 50+ years, I never said anything about gains so clearly u can't read 😂😂😂
2 valves introduce swirl, 4 valves give the charge tumble. Any more than that and the fluid dynamics get wierd. Valentino Rossi prefered the 4 valve arrangement motogp engine which is why Yamaha stopped using 5 valves. Yamaha's brilliance in engineering is something I have always admired but as a mechanic it usually means more difficult repairs and Yamaha is notorious for not keeping stock of previous year models parts. I own all 3 other Japanese brand bikes due to parts availability. My 1st 4 bikes where Yamahas, I loved all of them!
4 valves allow a central spark plug, the main reason its so popular
we had some success messing with the 5v heads, but changing the valve timing on only the center intake valve. Found a lot of torque from idle to about 4500, then signed off. If there was a variable cam timing available for the 5v heads, I think it could be phenominal, but in those days VVT was not really thought about much. We did it by having a cam grinding company regrind the cam (DOHC, so it had individual lobes), and later did a SOHC 660cc 5v with the same type deal but we had to re-engineer the rocker arms to work. Had we had more time (and especially money & manpower) I think we could have improved on the design even further. Like the prior, all of it was scrapped, as it was just some of us gearheads in a garage trying to make stuff work "better"-and when one of "us" (them) decided to stay out too late & party, it kind of got old having to work around their bad habits which caused some arguements.
Great video, thank you. I didn't know about the 7 value Yamaha's.
Loving the frequent uploads Visio! ❤👍
Yamaha has had their fingers in almost any form of performance engine built over the last 50 yrs. It’s crazy.
my fazer 1000 was a 20v engine, and without its exup it felt super gutless, but the power band was nice after 7k rpm. Sounded super smooth and happy to be up in that rev range. The head never failed on that bike with 70k miles, but their transmissions didn't live long to tell the tale.
Japan's technological capabilities
Petrol engines are beautiful.
I had a TDM 900 and a FZS1000s, both of them with 5valves setups. Great bikes!
Lets not forget, they designed the heads and most of all the exhaust and literally tuned the chassis of the Lexus LFA
Damn i enjoy these videos
Thanks Visio racer
Even the 5 valve was a flop- while it made a great torque curve, it was down on horsepower. It's the old hemi curse; maximum breathing alone isn't enough without proper combustion. After that, everyone settled on the 'pentroof' 4 valve style as the best compromise.
4 valves is just the magic number for a round combustion chamber, it provides the biggest gas flow without making the valve train overcomplicated. Specialty designed exhaust improves gas scavenging and intake compressor shoves more air into the engine, so that efficiently solves both issues that large number of valves were meant to solve.
The whole reason anyone even went the route of making more valves over just using a turbo is the arbitrary racing rules and restrictions that they had to work around.
Recent new design have proven 5 valve gives greastest power and torgue combined with a state of the art combustion chamber designed by Patric Miller Engeneering
Ive been aware of the 6 and 7 valve heads for a while. But Ive never seen pics of the ports for those heads. Im very interested in the port design for those heads.
While on the topic of Yamaha. I recommend falling down the rabbit hole of their snowmobiles. On the cutting edge of engine technology there too.
I appreciate every single one of your videos.
Keep up the great work!
Sadly they've recently said that they'll exit the snowmobile business.
@@Guovssohas
I know eh, very disappointing.
habe gerade eine 750 , Yamaha , Baujahr 1986 überholt und war ganz erstaunt dass der Motor fünf Ventile hat und in dieser Zeit war Yamaha der Konkurrenz voraus.
Might as well go with no valves and giant ports at this point
did many a valve adjustment on the 5v Yamaha's. And a bunch of 4v Yamaha's. And a ton of 2v and 3v as well. Yes they had a 3v (50cc). I don't miss it but looks like I may get back into it again, 4 year break from working on Japanese stuff and the boss wants to buy a Yamaha dealership.
doing the valves on a Genesis takes patience, concentration, and a steady but methodic approach. Also requires some good organizational skills to keep up with shims and such. Ain't all that hard if you keep up with everything. Time consuming though!
Yamaha is so cool ❣️👌🏼
I Love Yamaha 😅
Love from Berlin 🇩🇪
Ramsi 🙋🏻♂️
While the 7 valve head seems too complicated to me and everything above 4 or 5 valves on a smaller engine doesn't bring benefits, the use of 6 valve heads in production engines was real.
The Maybach MD650-655 and 870 diesel engines for marine and railway traction usage had 6 valve heads, these were operated by only two overhead cam shafts, one of these shafts also operated the mechanical pump/injector units on each cylinder.
It would be interesting do do a topic on these engines as they were very advanced for the early 1950s when they were developed, I worked on one of them and setting all those valves and injectors is a very intricate job.
I remember the genesis engine. Used to want a Radian pretty bad back in the day. 😂
1:34 was the saddest clip I have ever seen, had enough power for 2 more gears
Didn't maserati try to make a 6 valve and relised that 5 valves was the most efficient design and since then its been accepted beyond 5 valves has no benefit
I had the '84 FZ750 for 20K miles- awesome engine.
One nice thing about 5 valve heads on Yamahas, the smaller intakes hold lash adjustment for a long time. They do like to be fueled on on the richer side, and a bit more spark advance than a 4 valve head, as they aren't as efficient a combustion chamber shape and as a result don't burn as fast as a 4 valve head.
I had a nicely Ivan's Performance tuned '06 FZ1, it was a liquid revs kind of beast on the cam from 7K to the 13K rev limiter I saw Jesus quite a few times on it 😆
Yamaha was ahead of the game with this.
I loved him showing Wes Cooley on a Suzuki as an example of a Yamaha race bike
Yamaha does not use the 5 valve anymore, much less a 7. An overcomplicated and heavy sales gimmick that ran its course.
Err no not quite , the 5 valve head was better at the time but eventually materials / development caught up and allowed a four valve design to match the 5 valve head .
@@Dwainpipe21 Not sure what materials development altered physics, but gas flow through a poppet valve is tied closer to total periphery than area.... until the valves crowd each other and the periphery effects clash. The breathing advantage of a 5-valve was always marginal, if it existed, and the cost (in every meaning) was high. Maybe worth if from the marketing side, but when that petered out, goner.
@@ElsinoreRacer I read when they went back to 4 valve design it was because 5 valves allow more revs better control of the valves as the valves are lighter ( smaller ) but with modern materials a 4 valve head is just as good .
Love your content
Nothing like a good Micron exhaust pipe back in the day (before the company went away). Nice deep tuned tones. Everything today is raspy loud obnoxious and expensive when it comes to exhausts.
I was a Micron dealer in the mid 90's. Nicely made pipes but heavy.
@@mikerieck306 They were pretty common, not sure what caused that company to stop producing. I liked their rainbow colored heat treatments. Mainly, they were a simple oval or round shape at varying lengths and the tone they produced was very complimentary to inline-4 cylinders. Today exhausts cost a LOT more, offer less reduction of loudness, offer a much worse tone, and have far more expensive and complicated materials and shapes.
Thanks again
I have a 1995 yzf 750r it sounds amazing
How many valves do you want?
As many as possible. If you have to rebuild one I feel like it would be a real pain. But I trust in Yamaha to make a lot of good things
Rotary valve would eliminate the design problems with poppet valve systems, but there's a few challenges to overcome with those too.
Gud vid, been here since beginning 😮
I'm just here for the "Howeather"
Edit: What?!? Dude I've watched your channel since like 30k subs and you're finally nailing however
Yamaha Always Ahead, Unique, Extraordinary and Unbeatable....
Why not have all valves for intake as well as exhaust, with an alternating flap in the attached canal sending the gasses the right way?
I find this interesting. The most common 5V head I encouter is in the VW 1.8T in the B5 Passat and MKIV GTI.
Once GDI was introduced, it seems like there wasn't a way to build a 5V engine. Perhaps 5V GDI engines can be build but it was not worth it.
There are 5 Valve GDI engines, but their sparkplugs are offset and not great for road use.
@@SlowSTEN Oh, okay.
You should make a video about 14 cylinder engines.
Was hoping to see the cam/rocker/lifter bucket arrangement on top of the 7 valve head. Still hoping.
Freevalve technology could make this almost viable.
What I am really hoping for is that freevalve technology will revive the 5 valve per piston design.
Yamaha is a musical instrument manufacturer, first. That lends itself into the study of airflow, of resonance, engines breathe, and make music too.
Like the VW 5V?? I always wondered why they didn't take off, also the valves a more smaller and they WILL crack with heat.
I needed all the power i could muster back in the 90's racing superbike in the AMA FUSA and WERA and Suzuki IMHO had the best potential for me.....i was 6'4" and 250 with my leathers...lol
Like to believe that had Yamaha been able to diversify as a low-volume sportscar and kei car producer (e.g. 1961 Yamaha YX30 prototype and a 1958 kei car project) vaguely similar to Lotus (and like Lotus its engineering department working with other carmakers), that 5-valves and maybe bi-turbos would be its USP. Would they have been crazy enough though to try and develop 6/7-valves for cars like Maserati did with a 6-valve engine in the 1980s?
Good work keep it up
Watching your channel from 2013
Welcome time traveller!
@@fidelcatsro6948 oh man when I say your comment it would be like panic attack🥴🥴🥴🥴🥴🥴🥴
@@custommodspresentation5338
please go back to 1970 and buy a genuine German VW beetle for me for 3000 dollars and bring it back to 2024..
@@custommodspresentation5338
im from 1896 myself😆
@@fidelcatsro6948 man what can i say I want to jump from forth floor twice😇😇😇😇😇😰
Yamaha design goes round in circles, i see an XSR700 and XSR900GP there
So basically a motorcycle version of the Toyota 4AGE 20valve?
That is a Yamaha designed Head on that . They design Heads for a Shit-Ton of other people .
@@johncunningham4820 yes I'm aware of the Yamaha Toyota joint ventures. Yamaha are about harmonics and sound....as per the LFA 👌
I've got one of each luckily enough
@@jameshatton4211 I was just trying to Educate , in the event you Didn't know . Not belittle you .
Actually , Harmonics yes , but FLOW DYNAMICS is the other thing .
A Crisp sound is a byproduct of That .
Also LFA is a V-10 . They ALL sound awesome anyway .
@@ChroniclesofKToyoda . One each What ?
Doing valve clearances would probably take a whole day to do
Now machinists and alike are given the option of rotary valves with less loading and higher rpm's.
Why not build a engine with two pistons and Sharing the combustion chamber, similar to a split single, only using 4 stroke it will allow more valve area than piston area, use two rod journals and minimum space between pistons. Something like the oval piston engine only more reliable and easy to build. Say a 125 cc engine using two 50 mm bores with four, 20 mm intake valves and four 18mm exhaust valves, or 26/22 mm intake/exhaust. The combustion chamber width of two 50mm bores, would be about 110-120 mm say 50 x 115 mm the flow should be off the charts and cam timing and exact piston timing can be "adjusted" to induce swirl by opening on pistons valve just before the other. And closing earlier, with the othercloding later. Causing swirl in the cylinder. Mixing the air fuel. Keeping the port velocity high. Making power even better imagine two cranks four pistons, with single head and chamber having valve area larger than each piston say 50mm bores, with 3x 38 mm valves on the intake and 3x 34mm exhaust valves with 4 plugs firing at once. It Would be interesting to see if nothing else!
You would think the 6 valve would be arranged like the 7 valve with the plug in the middle and indexed towards with intake valve. Or running a twin ground strap plug.
The 6 valve head used on a Ducati seemed a much better design, with 2 spark plugs.
People forget the much lauded Nissan RB26 "is also" a Yamaha developed motor
& all this because Toyota engineers branched into Yamaha from what predated even TRD
There are many more engines developed by Yamaha
@@VisioRacer yup Volvo & Ford are also among those that come to mind, but yeah, Donut Media did a video on how they started from a group of Toyota's Engineers who were responsible for racing & engine development. I'm glad I have a few of their engines including a couple 5 Valvers, wish they'd kept them going
Also some model of porsche i heard..
I did not realize Yamaha was involved in the RB26DETT.
@@skylinefever Albrecht Goertz of Yamaha is responsible for his working with Nissan, even though the official partnership with Nissan feel thru his designs are still reflected in the L series, RB series & the Nissan Fairlady which all stem from the 2000GT project which originally was meant for Nissan
Ironically Nissan thought it not financially viable so Goertz took the project to conservative Toyota & we got Japan's first supercar the Toyota 2000GT, but if you look up Nissan 2000GT you will find what resembles a Corvette Stingray front with a Fairlady Z body
Under it's hood was the R&D that led to the L series which if you know is what evolved to the RB, though the RB is closer to the original Yamaha R&D. The story was supposedly that Nissan didn't need the partnership, but if you look at what came of it Nissan clearly reused the Yamaha derived work
The difference is, it's Nissan take on Yamaha R&D that was developed for them but doesn't credit, which in Japan is legal, it's how the Yamaha derived Toyota 2ZZ basically has iVTEC before Honda when Honda only had VTEC before Toyota's VVTLi, they both took each other's ideas
TLDR; reason most don't know Yamaha's designs lead to the RB is because within Japan you can take others ideas so long as you add your own twist or pay royalties a few years. Yamaha for example doesn't get to gatekeep who uses their research(even though in this case it was for Nissan), it's part of why Japan has a leg up on innovation, because they have to constantly innovate something new to stay relevant against their own R&D, it's also why they can't sue Nissan, just like how litigious Nintendo can't go against PalWorld since their IP is both Japan based
5v per cylinder is best. The valves begin to shroud each other and block the flow of each other the greater number after this. 3 intake valves and 2 exhaust valves.
Basicaly the act of pushing the valve into the cylinder causes you to lose more volume so the displaced volume of hte valve also the smaller and more numberous the value the smaller the port to flow gas through. Also the extreme at the other end, is bad, so many tiny valves causes the skin friction drag to increase at a much higher rate than a small series of larger ports.
5V per cylinder is the best.
I've seen the thumbnail change three times
Yes, the A/B testing
4:32 What engine is this?
Genius and insanity are close relatives...
Search the supersingle with 6 valves
Yamaha: "We're worried about the power limits of 2-stroke engines."
Detroit: LOL... Thou doest worry too much over nothing.
Wartsila: That table you are having your crisis at is the top of one of my pistons.
Yamaha was tweakin off that shit.
Why no mention of the legendary 1.8t VW engine? Best bang for buck for regular blokes. Those 4age engines are completely pointless when even simple unknown engine costs 1500+eur
The 750 yamaha 5 valve had poor combustion chambers when the compression ratio was raised for racing since the chamber became the valve pockets and quench area. As a result it could not compete with a 4 valve except with regular lower octane street gas in both engines.
Why does the single cylinder test engine look like a rotax 🙃 5 valve head even looks like an aprilia 650 head
I love my TRX.
The only other account I can remember of an engine with more than 5 valves is the V12 in Speed Racer’s Mach 5 from what I remember looking its specs up out of curiosity
Marvin the Martian’s spaceship had rack and pinion molecules!
I remember reading a really short article on an italian motorcycle magazine back in the 90s! I did not completely understand what that meant back then, as I was just a petrolhead cub, but I remember I thought "damn, that's some crazy engineering!", as I still think it is... It's sad that most of the R&D craziness of the past has been stopped because of cost and pollution reasons, now every new model might be cleaner than the previous one, but is also less exciting...
NR pistons are not oval, are oblong. I have been correcting this statement since the NR750 was born but people still keep using the same erroneus shape description.
Now think for a moment and picture an oval shaped piston section... Cartoonish.
Give yourself a break. It is oblong, but nobody knows this term.
Oh my...the first 5valve engines were somewhat a nightmare once you get valve seat recession, and to a lesser extent, stretched and deformed valves. Until the R1 the cylinder heads had this girdle-like camshaft journal that made work complicated. When better valvetrain metals had been available it made the switch back to 4 valves quite easy, uneven combustion was one of the issues with higher strung 5 valve engines. Can't drive up the compression ratio as high. Still it was very nice at its time!
its fruition not frution 4:34
A professional commentator would have helped the presentation.
Seus videos devem ser ótimos.mas não entendo nada de inglês. Se você colocar algum tipo de tradução em vários idiomas seria de grande ajuda.e conseguiria mais inscrições.
5 valves per cylinder seems to be the perfect level of sophistication. It's power advantages are already questionable compared to 4valves setup and of course fuel consumption increases massively. Still it's cool. 7valves per cylinder is just ridiculous, too complex and too much added friction in the valvetrain which lead too to much parasitic loses.
All these multi valve engines, and a BIG American V8 pushrod engine can rev to 9,000 rpm (11,000 for the Ilmor Indy car), if you scaled down the big V8 you could increase the revs corresponding.
7 vavles that just too much😮
i would live to see a "single valve" head with a singular massive valve per cylinder but with a couple of rotary valves above to actually controll the intake and exhausr
A diesel doesn't even need the rotary valves, you can just not have an exhaust or inlet manifold. Packard made a diesel radial like that, the DR-980.
There was also a rotary (spinning radial engine, not the dorito type rotary) called the gnome monosoupape that worked a similar way, but being a spark ignition engine it needed a secondary set of inlet ports at the bottom of the cylinder to get fuel in.
Were VW 5v engines somehow related to yamaha's ip of this technology?
Too many valves makes it impossible to make straight ports and curves in ports slow the air down
Yeah, everything has optimum number, more or less will useless..
Correction : the Volvo B8444S engine is actually built and designed by Yamaha to volvos specs. Volvo had engine bays designed for 4-bangers and 5-pots but needed a more powerful engine for their xc90 and s80 passenger cars for the american market. I guess someone told volvo engineers that americans wont buy their swedish car unless there is a v8 under the hood or something. Anyway, after this went sideways and the americans didn't really like the v8 volvos, Yamaha decided that since they had built such a crazy small v8, they'd just turn the heads upside down into a hot-v configuration, tilt it on it's side, slap a shaft and a propeller into it and call it a day. Thus the yamaha v8 outboards were born.
This is all ancient design we need 4stroke engines with simple reed valves
Yamaha couldn't get it right on the early yzf450s. Those things would puke fast, drop valves and destroy the engine.
Mostly due to not having wrist pin oil squirter!
That 750 Genesis wasn't even running right!
High flow but low velocity
Low velocity is good. It means lower pressure loss through the port.
✋🏼🇦🇺👍🏼
Слабо на русском рассказать?
More valves than there are girls available for Dipper to sleep with
(...is Tambry included as well?)
Edit: Also that Volvo V8 at the end sounds *amazing*
Edit 2: Right, about that whole "Dipper Pines' Wives" schtick: I counted 3 girls (Mabel, Wendy, Pacifica) plus Bill Cipher and Stanley Pines, but I omitted those 'cause Bill and Stan are guys and Dipper's a guy too so that makes it gay, not straight. So Yamaha made an engine with more valves than the number of Dipper's potential wives. *And no, Tambry isn't anywhere on that list*
Edit 3: Even *if* we factor in Billdip and Stan x Dipper, that still amounts to 5 compared to 7. So yeah, more valves than there are girls *and* guys available for Dipper to sleep with
475 views in 21 minutes? You fell off 😂😅
Basically anything over 4 valves is waste of R&D and the increased weight and friction diminishes any and all return
and the V-Max
Didn't maserati try to make a 6 valve and relised that 5 valves was the most efficient design and since then its been accepted beyond 5 valves has no benefit
Yes