Twitchy Throttle?

Hi all. I have just been riding my recently purchased vfr800 2001 model which has 60,000 kms on the clock. No matter how hard I try to be smooth coming on throttle from a fully closed throttle, which for me is usually mid corner, I can't seem to not jerk the bike as I open the throttle. This is naturally more pronounced in the lower gears.
Has other vfr riders noticed this on the fuel injected vfr's?
Is it something that can be improved? Mapping etc?
I still have a vfr750(which is much smoother in this regard) in the garage which I was planning on selling, but now am having second thoughts.

Try holding the bars a little looser.

fuldogg, Dec 18 2007, 12:01 AMTry holding the bars a little looser.

thanks for the tip. I have been to the aussie version of the californian superbike school which is a fantastic course, loose elbows was one of the tips I have incorporated into my riding.
Certainly a better rider may not have my gripes, however, there is such a stark difference between the carby version of the vfr and the fuel injected version that I'm questioning the bike.

lovevfr, Dec 18 2007, 12:29 AMNo matter how hard I try to be smooth coming on throttle from a fully closed throttle, which for me is usually mid corner, I can't seem to not jerk the bike as I open the throttle. This is naturally more pronounced in the lower gears. Has other vfr riders noticed this on the fuel injected vfr's?

The throttle on my '00 is a bit twitchy (compared to my carburated bike) as well but it is something you adjust to after a while. It's always on my mind in a low speed, low geared corner. After riding the bike a while you too will learn how to be relatively smooth with it. Now, having said that, it's hard to tell from your description whether what you're experiencing is just the normal touchy FI throttle that we all adjust to or whether there is a problem. Either way, I doubt there's a FI made that's as smooth in transition as a carburated engine. I prefer a carburated engine for it's buttery smooth throttle but don't miss the other problems and maintenance associated with them.

mick, Dec 18 2007, 04:50 AM

lovevfr, Dec 18 2007, 12:29 AMNo matter how hard I try to be smooth coming on throttle from a fully closed throttle, which for me is usually mid corner, I can't seem to not jerk the bike as I open the throttle. This is naturally more pronounced in the lower gears. Has other vfr riders noticed this on the fuel injected vfr's?

The throttle on my '00 is a bit twitchy (compared to my carburated bike) as well but it is something you adjust to after a while. It's always on my mind in a low speed, low geared corner. After riding the bike a while you too will learn how to be relatively smooth with it. Now, having said that, it's hard to tell from your description whether what you're experiencing is just the normal touchy FI throttle that we all adjust to or whether there is a problem. Either way, I doubt there's a FI made that's as smooth in transition as a carburated engine. I prefer a carburated engine for it's buttery smooth throttle but don't miss the other problems and maintenance associated with them.

It's probably the FI thing. I might test ride other vfr800 just as comparison.

Make sure your chain is not loose, that'll make things worse.

Also that there's not too much slack in the throttle cables. I prefer mine as tight as I can get them, without affecting the RPMS when moving the handlebars fully side-to-side.

I'd second the "adjustment phase" theory... try giving it some time. I'll bet if you get relatively adjusted to the FI going back to the carbed bike will seem sluggish. My guess is the FI responds quicker than the carbs, making it seem twitchier. Drive chain does make a noticeable difference. Good luck, Good purchase (IMG:style_emoticons/oldemoticons/smile.gif)

1. Check throttle cable to eliminate slack.
2. Check the chain to make sure it is not loose.
3. Practice, practice, practice. A smooth hand did not come naturally for me.
4. Play around with body position. Grip the tank with your knees; support your weight with your abdomen, not your hands.
5. If none of that works, try a Power Commander/O2 eliminator setup and remap. This did wonders to smooth out the low end RPM range of my '02.

Hope that helps.

You've correctly identified the only flaw with the FI bike. Some say a custom-mapped PCIII will fix "most" of it, but FI will always be an "on/off" switch for fuel. Later FI bikes from other manufacturers (mostly race bikes) have more sophisticated tech that makes them smoother, but the early-tech VFR is what it is.

I owned a '92 VFR while I also had the '98, and I really wrestled with the decision with which one to keep. For me, it came down to the fact I'd just gone through (lots of maintenance/minor upgrades) the '98 and would have to do it again for the '92. You might try dialing in a PCIII. If not, ride them both and decide whether the FI gives you enough extra (torque, handling, etc.)to overcome the twitchiness. It'll be close.

It's likely the EFI. In time you'll develop "the VFR EFI touch" and all will be good. Ommmmmm . . . .

I second all that has been said, and will add one item - to ensure the rotating throttle grip and cables and the mechanism they attach to at the throttle bodies are all properly lubed. A sticky throttle/cable/linkage will cause higher wrist effort, exacerbating the problem.

My 95 was SOOOOO smooth and perfectly carbed, the 2000 I have did not feel as nice in the on/off area. Do test ride another FI bike, to see if yours is on par with others. In fact, a bike with a lot more torque makes this problem even worse - the stock RC51 has a hella hit mid-corner. a PCII helps some, but developing extraordinary throttle control is the only way to deal.

thanks for all the advice.
I think it will be easier and cheaper to fix the rider side of the bike/rider interface. The 800 does have a heap more torque over the 750. It will be hard but I will let the 750 go to a new owner. It had easily been the best riding of my 9 years of riding.
Any novices out there thinking of buying a mid size bike should buy a vfr750.

After checking all the technical stuff, just work on a very smooth throttle hand and it will become a good natural habit pretty quickly. IMHO, riding well is very much a mental thing. Creating good habits is a key to survival and fun.

I've ridden my VFR then jumped on my snob bike on the same day and with 63 more HP, the throttle is twitchy for a few blocks then the smooth hand adjusts and off we go into enjoyment again... (IMG:style_emoticons/oldemoticons/wink.gif)

Main thing is just ride. (IMG:style_emoticons/oldemoticons/fing02.gif)

Is your chain tensions correct?

As mentioned adjust your throttle play, to much play in the cables is one of the biggest contributors to a snatch y throttle along with the fact that all FI bikes seem to have a more On/Off feel off idle.
Enjoy and welcome! (IMG:style_emoticons/oldemoticons/beer.gif)

I used to wonder the same thing, but I just learned to control my wrist a little better with time and practice. When I get careless, I tend to snap it open too abruptly......which sucks when you're leaned over mid corner! Just need to be mindful of your throttle action. I need to adjust my cable slack slightly too.

chain tension I believe is as per manual. Infact chain and sprocket is brand new which I'm proud to say I did myself.( First time and took about 5 hrs). Throttle play is not something I considered so I'll check that.

Sounds like folks have you covered. F.I. on bikes in general seems to be twitchy. Nature of the beast. A P.C. can help, but you'll be a better rider if you can adjust to it. .02 (IMG:style_emoticons/oldemoticons/wheel.gif) (IMG:style_emoticons/oldemoticons/wink.gif) (If I can do it,.....LOL).