Note: I'm aware of the idea, that the valve provides back pressure, however I feel its too flimsy and too far back in system for that. Please comment if you have info to verify other than anecdotal thanks.
Hi Graham, the idea makes sense, but then the VFR should run awful with aftermarket exhaust pipes and no reflashing, think about it, the injection would still think the backpressure is needed to empty the combustion chamber, and the timing and everything... And it is not the case. I never gave a deep though to it, but I tend to think it is more for a sound thing, low revs less noise, if you drive it in the city not on the red zone it´s more "friendly". I cannot think of other reason. Regarding the vtec as far as I´m concerned does not need any kind of back pressure - previous models of VFR did not have any kind of valve like this. And emissions are not related, any kind of catalyst you might place there does not need back pressure. So I really tend to think it´s for the sound. Back pressure could have an influence on 2 Stroke engines, but 4 Stroke with exhaust valves that influence would be very limited. If there was any benefit of it in performance, the exhausts for racing would have it, and they are not like that. Nevertheless, if someone has better knowledge he might share it as well :)
@@capitanscott Thank you for the great comment. Yes I'm convinced it has no reason other than noise regs. I only mentioned it as youtuber Mark Savage did a piece on it suggesting back pressure, but I wasn't convinced. However 4 stroke valves such as exup, do help back pressure but for mid range torque, obviously not really required in race engines due to their time at high revs.. Exhaust valves are often to overcome valve overlap at low revs, so as the vtecs have lower cam profiles for lower revs, i guess they don't need them Being a massive 2 stroke fan in 70s ,i witnessed the effect of poor exhaust flow, when we used to put beautiful sounding 3 into 1 pipes on our triples, totally killing top end power. Thanks again for interesting input.
Hi Graham funny enough i disconnected mine about ten days ago , sounds much better and car drivers actually hear you now , which is a bonus. The other thing is since i have been using it , the low speed throttle control has improved alot to the point its very smooth now, which was a suprise, wasn't expecting that 🤔
Oh, good coincidence. Yes I might try it when back on road proper, although probably re connect as I'm a standard fan. Be Really interesting to see if I notice any improvement. Thanks.
@@JIMWSMITH I replied on my previous vidro Jim, it was M&p accessories Swansea, they said only 2 left when I bought it, but that might have been a marketing ploy.
Hi Graham! I'm very happy with all your videos. Since I own a VFR1200F myself since a few months, I've been using your yt channel as an amazing guide to get to know my bike better. In particular this one about the exhaust valve. I've been looking how to keep it open and boom, you show up and I've done that. And now it sounds amazing!
@@Grahamvfrso I've been riding with the valve open and believe me. There's zero difference in power, so the valve is just there for sound regulation, I guess.
@@Mj.Hondaa absolutely yea, it's much too flimsy and far back in the system, to aid scanvanging/back pressure etc. So yes think you a right, just a noise reg thing. Thanks for input 👍👍
The idea is that with that valve closed you get more torque at low revs which makes this bike more useful in the city and you don't have to rev it like the young lads do. This is a gentleman sports cruiser and should be left as intended. There are some misunderstandings on the used market where they have aftermarket can and original is missing. Those bikes are harder to sell.
Well I only ran it as an experiment for 50 or 60 miles, but didn't notice any difference. It's only a noise thing, it has no effect on scavaging, back pressure etc. 😊
Hi graham i took the cable off mine at christmas sounds loads better again not had chance to try it due to weather as of back pressure wont make a difference the valve is fitted for noise regs was going to get a race can but will try this mod first . Will fit my philips h7 gt200 brighter headlamp bulbs in the morning on my days off now back in work wednesday will be in contact with you about how much brighter the bulbs are i know they are going to be a pain to fit.
Yea, as I said to one of the other lads, I may have a run with it disconnected, but knowing me, I'll probably just put it back on. I was doubtful of any back pressure benefits, think Mark Savage (youtuber) had mentioned it. Seen a couple of vids on the vfr bulb replacement, yea looks a cuss and a swear job. Roll on warmer days.
@@Grahamvfr well graham headlight bulbs done not 2 bad to do took me a hour to replace both of them and thats unlocking my gates and the garage door and moving the bike around. Those philips gt 200 race vison 200% bulbs are loads brighter and are the same 55 wattage as the standard bulb and are still legal would definitely recommend replacing the standard ones for the philips ones. Leave the the flapper cable off and enjoy the v4 honda howl !! yes i have watched mark savage review on the exhaust thats where i got the idea from.
@@Grahamvfr HI Graham its not weather for vfr very windy here and rain will do my weekly start up in the morning run the all 3 vfrs till fan kicks in roll on better weather .
Yea once you've removed rear panel see this link if you've not done that th-cam.com/video/hNxP4K2wzsE/w-d-xo.html Then simply rotate the servo wheel, it will have some resistance, to gain slack on the cable, then with a fiddle unhook cable from wheel. Hope that helps.
Note: I'm aware of the idea, that the valve provides back pressure, however I feel its too flimsy and too far back in system for that. Please comment if you have info to verify other than anecdotal thanks.
Hi Graham, the idea makes sense, but then the VFR should run awful with aftermarket exhaust pipes and no reflashing, think about it, the injection would still think the backpressure is needed to empty the combustion chamber, and the timing and everything... And it is not the case.
I never gave a deep though to it, but I tend to think it is more for a sound thing, low revs less noise, if you drive it in the city not on the red zone it´s more "friendly". I cannot think of other reason.
Regarding the vtec as far as I´m concerned does not need any kind of back pressure - previous models of VFR did not have any kind of valve like this.
And emissions are not related, any kind of catalyst you might place there does not need back pressure.
So I really tend to think it´s for the sound.
Back pressure could have an influence on 2 Stroke engines, but 4 Stroke with exhaust valves that influence would be very limited. If there was any benefit of it in performance, the exhausts for racing would have it, and they are not like that.
Nevertheless, if someone has better knowledge he might share it as well :)
@@capitanscott Thank you for the great comment. Yes I'm convinced it has no reason other than noise regs.
I only mentioned it as youtuber Mark Savage did a piece on it suggesting back pressure, but I wasn't convinced.
However 4 stroke valves such as exup, do help back pressure but for mid range torque, obviously not really required in race engines due to their time at high revs..
Exhaust valves are often to overcome valve overlap at low revs, so as the vtecs have lower cam profiles for lower revs, i guess they don't need them
Being a massive 2 stroke fan in 70s ,i witnessed the effect of poor exhaust flow, when we used to put beautiful sounding 3 into 1 pipes on our triples, totally killing top end power.
Thanks again for interesting input.
I've disconnected mine today and it feels lot smoother at low rpms city driving. Love the sound 😊
Nice one 👍
Hi Graham funny enough i disconnected mine about ten days ago , sounds much better and car drivers actually hear you now , which is a bonus. The other thing is since i have been using it , the low speed throttle control has improved alot to the point its very smooth now, which was a suprise, wasn't expecting that 🤔
Oh, good coincidence. Yes I might try it when back on road proper, although probably re connect as I'm a standard fan. Be Really interesting to see if I notice any improvement. Thanks.
@@Grahamvfr were did you get your screen from , been trying to find one online ..
@@JIMWSMITH I replied on my previous vidro Jim, it was M&p accessories Swansea, they said only 2 left when I bought it, but that might have been a marketing ploy.
@@Grahamvfr thanks graham , fingers crossed !
@@Grahamvfr Bough my VFR 1200 from there 3 years ago :)
Hi Graham! I'm very happy with all your videos. Since I own a VFR1200F myself since a few months, I've been using your yt channel as an amazing guide to get to know my bike better.
In particular this one about the exhaust valve. I've been looking how to keep it open and boom, you show up and I've done that. And now it sounds amazing!
Well that's really encouraging to hear thank you.
Yes the valve open certainly let's the v4 roar 👍.
@@Grahamvfrso I've been riding with the valve open and believe me. There's zero difference in power, so the valve is just there for sound regulation, I guess.
@@Mj.Hondaa absolutely yea, it's much too flimsy and far back in the system, to aid scanvanging/back pressure etc. So yes think you a right, just a noise reg thing. Thanks for input 👍👍
Sounds good Graham but i will keep it as is, as i like to hear the change in the exhaust note when the revs build up. Keep up the good work
Thanks, yes I love the switch in sound.
Thank you for the video! It was useful
Appreciate your comment, pleased it helped 👍
Thanks for all the videos you are doing to this model
Glad they help.. Gracias
Thank you Graham for the great videos you provide to us, your attention to detail is appreciated (-: Subscribed
That's really great to hear, thank you for watching. 👍
The idea is that with that valve closed you get more torque at low revs which makes this bike more useful in the city and you don't have to rev it like the young lads do. This is a gentleman sports cruiser and should be left as intended. There are some misunderstandings on the used market where they have aftermarket can and original is missing. Those bikes are harder to sell.
Yes gentlemens express I tend to call it.
As a restorer rather than modifier I usually leave things as close to standard as possible. 👍
Sounds much better,, thx
No problem 👍
There is 3 year i am a VFR owner. Today i realise that my exaust is « Free » since 3 years LOL
Well done haha... Thank you, for watching.
So the valve itself is actually in the chrome end muffler ? If I would buy a slip on exhaust, that would bypass the valve ?
Yes no problem there, and providing you don't remove the servo, just release the cable , it'll be fine. 👍
Do you notice a change better or worse in performance or gas milage with this change?
Well I only ran it as an experiment for 50 or 60 miles, but didn't notice any difference. It's only a noise thing, it has no effect on scavaging, back pressure etc. 😊
Hi graham i took the cable off mine at christmas sounds loads better again not had chance to try it due to weather as of back pressure wont make a difference the valve is fitted for noise regs was going to get a race can but will try this mod first . Will fit my philips h7 gt200 brighter headlamp bulbs in the morning on my days off now back in work wednesday will be in contact with you about how much brighter the bulbs are i know they are going to be a pain to fit.
Yea, as I said to one of the other lads, I may have a run with it disconnected, but knowing me, I'll probably just put it back on. I was doubtful of any back pressure benefits, think Mark Savage (youtuber) had mentioned it.
Seen a couple of vids on the vfr bulb replacement, yea looks a cuss and a swear job. Roll on warmer days.
@@Grahamvfr well graham headlight bulbs done not 2 bad to do took me a hour to replace both of them and thats unlocking my gates and the garage door and moving the bike around. Those philips gt 200 race vison 200% bulbs are loads brighter and are the same 55 wattage as the standard bulb and are still legal would definitely recommend replacing the standard ones for the philips ones. Leave the the flapper cable off and enjoy the v4 honda howl !! yes i have watched mark savage review on the exhaust thats where i got the idea from.
@@andyrawlings5369 Thank you for the update Andy, glad you got them sorted OK 👍
@@Grahamvfr HI Graham its not weather for vfr very windy here and rain will do my weekly start up in the morning run the all 3 vfrs till fan kicks in roll on better weather .
@@andyrawlings5369 Yep roll on sunnier drier climes.
Hi Graham, how do I disconnect the cable from the servo unit?
Yea once you've removed rear panel see this link if you've not done that th-cam.com/video/hNxP4K2wzsE/w-d-xo.html
Then simply rotate the servo wheel, it will have some resistance, to gain slack on the cable, then with a fiddle unhook cable from wheel. Hope that helps.
@@Grahamvfr yes just done it mate, sounds better (in my humble opinion)! 👍🏻
@@clintneville9767 Nice one, yea it does, but I'd miss the change of note as it opens... Little things and all that haha.
@@Grahamvfr good point, will see how I get on might put it back, we’ll see!