hesitation on 6th gen at level throttle

thanks all for tips and suggestions!
I didnt think the exhaust mod would have had effect. Thanks for corroboration...
PO had went one down on countershaft sprocket and one up on rear 15/44
im keeping it at around 5k cruising and she is still jumpy, hiccupy at no load. It seems a little better since ive been oiling the chain every night... maybe its my imagination tho
anyhow i ordered new chain and sprockets, since they are consumables anyhow and that will at least rule it out one way or another.

 

a gear change like that will make it eat more gas, just got +2 in back, your at like +3.5-a bit too much

 

Aimbot, I haven't heard of cleaning the "starter valves". What is the gauge about? I'm gonna look at my service manual when i get home.

 

Balancing the Starter Valves will help make the VFR feel crisper from just off idle for example accelerating gently from a red light.

Your issue sounds like its caused when cruising due to going into Closed loop. My Gen 6 when I had it would be worst when gently cruising roll off the throttle then rolling back on, a power commander and O2 sensor eliminaters was the standard cure.

 

synched starter valves which helped a bit. Blocked PAIR valves with marble and ordered plates so i can eliminate the reeds and do it right.
Finally, got 330 ohm resistors and bypassed the o2 sensors - problem solved, except for slight loss in mpg. Is this is really a good long term solution or do i now need a PCV?
I still think something is wrong tho- still hiccups at small throttle openings, but only in 3rd gear now...?????
thanks again for help!

 

What is the spec you used? Did you synch the starter valve circuit to the same value or offset? Note, the more I read about the starter valves the more contention I find so YMMV. It seems that 6th gen Honda documentation says to synchronize the four valves to identical vacuum. However, this does not necessarily make sense and some think that one should maintain the 5th generation settings. The on/off behavior from 0% throttle to 4% is smoothed out by staggering the vacuum, thus getting the cylinders to begin firing in sequence rather than all at once. I yield to others but I think the 5th gen spec states to synch all to the same vacuum, then set then 1 at +20, 2 and 3 at -20. I would also suggest setting everything to stock before doing this. Make the OEM change first otherwise non-recommended changes may mask an existing problem.

 

Nothing good ever happens below 5K . . .



Seriously, though, the VFR has some fueling issues from the factory - snatchy throttle response at small openings and flat spots. I am with NorcalBoy. A Power Commander and Dynotune made all the difference in my VFR.



.

 

hey Knight,
I read a lot on the UK vfr site about that, but people here seem to still set them flat to #4, so thats what i did. Plus, I used a homemade manometer wi 1/4" tubes and ATF fluid so I couldnt easily set them all different. I guess I could figure out a conversion factor tho using the single vacuum gage i have. I will try it next time i have the tank up.

have you done it using 5th gen specs and found a difference?
it makes logical sense that it might, but im no engineer!

 

"im no engineer! " I studied electrical engineering. Oh wait I work in computers today, so I am no engineer also.

This has not been checked on my 1999. I got it last year and did do a major refresh but my mechanic has done few VFRs thus the starter valves were not on his mind. As fall comes I am investigating a valve check and perhaps the starter valve synch.

Also, as I am a novice (these past couple months are 99% of the riding I have done), I would probably need you to ride my bike and tell me how the response is. I feel that it is very smooth off idle, that is my perception. But alas I do not have a good reference point.

 

mine was jumping around like a dog shitting peach pits...
no subtle thing! Not fun at all

 

Well while the previous owner let a lot of things go to pot, perhaps he actually adjusted this. It was hard to determine how severe the problem is until you quoted peach pits. Now I understand.

 

My 07 RWB has been cantankerous recently especially when hot. Crappy off idle throttle response and it would sometime simply stall when I pulled in the clutch as I approach a stop light. Last night I finally had the time to pull the tank and have a gander under the air box. I found "start valves" were sticking open and the ports were all gummed up. So I pulled the throttle bodies off to give the works a good cleaning, then a blow with some compressed air and finally I lubed the sticky valves and cycled them till they operated freely.

It's a new bike today with no idle issues and it has a crisp feel off idle. I didn't sync them as I ran out of time. I needed my beauty sleep! However, I will hook up the gauges tonight and fine tune them. I run a power commander V but even on the stock map my bike doesn't surge or have any issues between 3 and 4k like my older 2002's did.

I'm not completely certain whey we refer to these as "start valves". I think they should be called Idle Air Bypass Valves as that is what they do. I suppose that since the wax unit pulls them further open for cold starts is why the name came around. For me the term "start valve" makes me think that they are some kind of fuel injector. Just an opinion....carry on....

 

My '02 smoothed out significantly with the flapper mod, removing the airbox snorkel, and removing the PAIR valves and blocking them.

 

Interesting! My PAIRs are removed and blocked but I still have the flapper and snorkel installed. I may try pulling them tonight just for shitz and giggles.

 

I am all onboard with more appropriate naming schemes. Names are important!

The name did exist before the wax unit, while the control was a manual lever as on my fifth gen.

I just had a discussion here with someone who read that their owner's manual calls the fast idle lever a "choke." But it does not choke the system!

Honda, you got the name of the bike correct (Named after 1960's police interceptors) but YOU GOT ALL THE PARTS NAMES WRONG.

Okay just something I have been wondering and this is a good place to throw it in: Does the ECU know that the starter valves are open? The manual warnings seem to indicate that the mixture is richer. Maybe it knows that the rpm is high but the throttle is at 0%.

 

You don't have to pull the flapper ... just make sure it's stuck in the open position and plug the vacuum hose.

The snorkel, just pull it out and keep it safe in a box somewhere.

 

I am all onboard with more appropriate naming schemes. Names are important!

The name did exist before the wax unit, while the control was a manual lever as on my fifth gen.

I just had a discussion here with someone who read that their owner's manual calls the fast idle lever a "choke." But it does not choke the system!

Honda, you got the name of the bike correct (named after 1960's police interceptors) but you got the names of all the parts wrong.

Okay just something I have been wondering and this is a good place to throw it in: Does the ECU know that the starter valves are open? The manual warnings seem to indicate that the mixture is richer. Maybe it knows that the rpm is high but the throttle is at 0%.