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Honda used similar going way back but no one has done it as well as KTM

In the areas requested… yep. Our sx main event 250 made around 52 - 9 peak to peak gain.

@HPRaceDevelopment We didn't see that in this video. Gotta use similarly performing gas when comparing numbers as well. Counting oxygenated fuel as part of the build is misleading as well. Especially when the stocker is being compared WITHOUT the funny fuel. We saw 6hp here & probably 3 of that was the oxygenated fuel & the other 3 was the head. 😉 Just say'n.

@@barnescycle no different rod, crank, and head

@@yodavizion Why do you think a change to fuel and ignition can remove vacuum? Lots of myths out there…

yep. But the head wont work

As always the answer depends Mods starting at 500 and up

@@dlr3722 we used to sell it, we no longer do, for management related issues at stic

If you want to use it offroad - adding damping is a must. Most the street focussed bikes like that are designed for smooth road feel

@@paulygood6665 In this video? I dont think we are. In other videos Im waffling about it. Maybe maybe not!

@@paulmarshall8774 its a different yosh than what yosh sells - not sure whats different. The mapping changes obviously are worse on the dyno but people seem go think better on track. This is common in mapping where a little leaner and more ignition than what makes most hp is what riders often say feels best. This is a prime example of where often times a test rider is “wrong” in what they should do but its the engineers job to listen to the rider sometimes even if its wrong

@ thanks for the swift reply and answer 👍I was considering a WE but now thinking about a std 250 but with a big bore as I’m coming down from a Ktm 350

@@SLAYJUCE might have to buy some new wrists on this setting after that haha

✊😂

@@moto3463 you think they dont?

@@RedLightning correct I mis spoke. Ktm however has called them exact explor for a while now

Its exactly something ok!

@@westonwylie816 sometimes worse without insert

What race fuel.

@@HPRaceDevelopment You said vp t4 and the other brand is race fuel??

@@Qwerty-r2v1l You can with work

@ Can I run a spacer under the cylinder for the longer rod or would I have to machine the head

@@ehess8845 oems maximize what is possible on pump gas. They own dynos too…and find the limit to what lives on pump gas .15 would be a huge amount of material as well, i think u meant .015 which is still a lot and not suggested for pump fuel

@@HPRaceDevelopment Fat fingers...yes, meant .015. Quick question if you don't mind regarding break-in of a fresh top end...3-4 heat cycles with no load, or heat cycles with load and progressively higher rpm? Or just ride it?

I thought of doing stuffers into those transferports and kind of copying Yamahas 5mw cylinder, it isnt best either but could be better. Correct me if I'm wrong

@@miroslav5647 put a lot of time and effort into dyno testing…thats how anything gets better!

we do

Can you share it? I'm looking at putting a pipe on a 25 yz85 and my young fella wants fmf cos that's what haiden deegan uses lol

@@nathanbenard2643 If we publish it we piss off fmf

@@RETROVERLAND Nice product - I wonder why ktm wont sell the stock settings as dave sells - they certainly know what he is doing and can test i better than anyone can

@@HPRaceDevelopment Would that product work with your Husky 300 Stage 2 works package or would we need to go to your GET?

@@frankokrisztian1400 i think they are good as well but most people dont

pretty similae

@ ok, what about one with a big bore kit? Yz144 specifically

@@JimG1964 the high speed adjuster does nothing on those shocks - so the only way is a revalve. If your issue is as you describe then more valving stiffness will help that area

@@HPRaceDevelopment Thanks for your reply.

If you like to rev the difference is small If you like to ride the torque curve the difference is bigger. Our website currently has the 290 on sale if thats something you are interested in.

@@rjbcscs69 Depends on carb mods, fuel, temps, and rider.

@@NightwishArena ktm has always been around 190 on ex and 126-128 on modern engines doesnt matter the year or bike cc

@@HPRaceDevelopment thanks. You have a lot of great stuff here. Just watched those ignition timing videos 👍

@@sebastianclauss4537 welcome to what it costs us the shop to do r&d

Heads are not ported on two strokes, but some OEM heads can be cut. We cut and machine oem heads for many of our race combnos and also have our own special head inserts and shells we sell for others. VHM is just one of many brands who sell race parts

@@HPRaceDevelopment do your cut heads perform better than vhm or other aftermarket brands?

@@nikolaskordzik-ky2ls Everything we offer is the best.

​@HPRaceDevelopment could you make a video comparing your best cylinder head and insert with vhm or some other aftermarket companies

@@nikolaskordzik-ky2ls if you dont find value to what we publish, or our multiple national championships - buy someone elses product. If you think you want to buy one of the best with actual real testing and championship proven results - buy ours

On the underside? Woudn't be a good place for the oil....the skirt outside and ring areas would be more ideal

@@benjaminemerald8027 Not sure on the noises. The old 100 bolts on but ex wont fit without changes

@@HPRaceDevelopment I have the Exhaust that goes w the 98 kx80/100 jug & I read on a kx85 forum alot of them make that noise I mentioned even brand new ones directly off the showroom floor, was just curious if there was a fix for it etc !.thank you for the info, when I advance the timing should I go a full line over or small increments at a time?

@@benjaminemerald8027 Every engine is different - advancing the timing on stock style porting engines and various head combos might make it slower... Typically EG combos have a low ex port and dont respond well to more timing

@@HPRaceDevelopment it is ported & head modified by Eric Gorr, not stock, & it should be alot faster than it is imo my stock 2018 Kx85 is faster

@@benjaminemerald8027 That's because it's done by EG. Sorry but he isn't the best with performance work....from years of experience of testing all that's out there and seeing what I've seen. "porting" is not all the same at every shop...heads are not al the same at every shop. And most places that overbore cylinders dont do good port work to actually make them run right - at the price EG sold those for - he could barely cover the cost of boring it, plating it, and cutting the head and PV along with a piston kit.

We have "fine tuned" our dyno process to shorten the track testing aspect. Most shops really struggle with this concept and optimize an engine to a dyno run (load time of their dyno and process they use). We have tried to optimize our dyno procedure to match what we have learned works on track. Lot's of variables go into this - how much fan on the pipe - and load time - how many runs you do back to back to back to back in what coast down town etc. It's a whole video topic in itself. But once we have a good ignition and jetting combo - we might vary it 1-1.5 degrees in a few spots to suit rider request. We usually sell our CDI's with 2 maps - one we like and 1 we think people might also like thats a little different. For the most part - what riders generally like is a little less hp in trade for a little more RPM.

@@HPRaceDevelopment thanks for the reply, I just sent you an email regarding a consult

Oh, no cylindr base gasket is a risk. I am using a 3M product called "Nitrilie gasket adhesive, brown, number 847", and so far so good after 5 gallons. That stuff blows Yamabond 4 away IMO. if I can stick to 100 octane gas, I will machine the base for the stock gasket again. Good simple mods, that moved the power down lower very well. Still smooth with the FMF pipe too. Jetting is a pain IMO to get very good, and i think I will get a bit more power,---with the 2nd more lean needle. I have changed every jet on this bike, and it is still pretty rich above the pilot.

@@EarthSurferUSA removing reed spacer is less power everywhere. Have published this over 10 years ago. lowering cylinder will sometimes help front side in trade for less power. If you race mx its generally worse. Cutting the head, increasing comp and tightening squish also hurts power, no measurable power improvement. alters power character feels more torquey in trade for rpm loss have owned 5 ys250s, raced them in pro, and built and tested more items on these bikes on the track and dyno than probably anyone still doing work to them.

@@HPRaceDevelopment I can tell you are very knowledgeable and I respect nothing more. The EXP I had on one bike of the past (I can't remember which one), I made and added a reed block spacer, and that mellowed the power hit for me (seat of the pants evaluation). This bike is set up IMO with higher rpm power, huge brakes, in a feeble effort to race MX against 15 more hp of a 450. That just is not gonna happen IMO, so the bike is not really set up well for anything (I am 60 now and woods riding in Michigan). The mods I did worked very well for more low end grunt and runs pretty smooth into the mid range. I am not sure how my top rpm I lost, (messed up and did not put a tach on it when stock), but it feels like a loss of about 500 rpm maybe. I don't notice it really. But here is something you have not seen before. I port little 30cc Zenoah, (used to be a division of Kamatsu. Now Husky owns the production in Japan still) engines for a living, used in 1/5th scale rc cars/boats and Go-Peds before the 1/5th scale cars came out. They have a 70's single exhaust port with 4 transfers. The interesting part is the front transfers (exhaust side) has a negative roof angle by about 5 degrees, and is bouncing the charge off the piston crown. I know Tom Turner (TSR software I have, and never totally figured out, lol) has never seen that before as I talked with him before he retired. The engines are high revving, up to 21,000 rpm, and can make up to 7hp (I calibrated my water brake dyno by using a new, stock engine, set it up like the manufacture did, no exhaust, no air filter), jetted it the best I could after total ring seal, and adjust my software until I matched the manufactures claim for the stock engine at 2.8hp. It seems to me from my research, there is really no calibration for dyno's, and that is the best way I could come up with. I do have a question about the KTM vs YZ exhaust port for you though. Why would the wider sub-exhaust ports on the Yamaha not make up the difference of the width (time area) of the main exhaust port? Good story too. I think it was 1993 when Kawasaki first went to a semi truck for the factory team. I did a bit of my own porting back then (just getting started) and somehow, a buddy of mine and I got permission to go into the trailer after the fans cleared out for the post race autograph session in the pits. So we come back later, he lets us in, and left us alone. There it was! A cylinder for Mike LaRacco engraved with his name on the bench, so I picked it up to take a lookie. That is when Big daddy Mike LaRacco entered the trailer, saw me with the cylinder in my hands, and kicked us out. :) Good channel sir, I enjoy it. But I could not hear the name of the pro you mentioned, Jeremy something. Buy the way. Since the porting I do is more of a production thing, (like 36 top end kits in a case that takes me a week to do), and I have a ton of machining exp, I may be the first person in the world to port 2-stoke cylinders with a CNC mill, starting in 2007. Doug in Michigan

Buy the way. Since the porting I do is more of a production thing, (like 36 top end kits in a case that takes me a week to do), and I have a ton of machining exp, I may be the first person in the world to port 2-stoke cylinders with a CNC mill, starting in 2007. Doug in Michigan I see the lack of the spacer for stuffing the crank case volume a bit more, and maybe the results depend on what engine is used. Not sure.