choppy low rpm's

hello gentleman.im a new owner of a 2003 vfr800 with 24k miles on it.its all bone stock with kn air filter.and my problem is bike is running like crap under 3500 rpm.especially when warmed up.
i eliminated the o2 sensor with 330 ohm resistors.at first i thought it made some improvement but now still very choppy and hesitating.i did the flapper mod and disconnected the pair valve.i read here that syncing the starter valves cures most of this problem.bike idles keeps moving between 1200-1400 rpms.where should i start from?any help would be appreciated.(i used to have a 2001 vfr for 1 year and 14000 miles.what a great bike that was.but i crashed it and so far its disappointing with the 6th gen)

 

I had the same problem with my 2003, I bought a used PC III (Power Commander) which improved the under 3500 drastically.

 

its such a shame on honda that a stock bike needs a 300 dollars pc just to run properly.

 

Not only fixes low range, but gives you complete control over mapping to match exhaust and other tuning changes. I traded in my 03 for a slightly used 14 Deluxe and love it. no problems with mapping.

 

Switch to carbs !! :behindsofa:

 

i had 99 r1,03-05 bandit 1200's,05 fz1 and i had really bad luck with carbs in general.on the other hand my friends zrx1200 is smoother than any injected bike i have ever ridden.

 

So I had an off-idle stumble show up after I did the flapper mod. I reverted back to standard configuration and stumble was gone. Engine seems to run lean near idle and is very sensitive to air flow. Mine is a 2006.
The KN filter could also make it worse IMO.

The variation in idle RPMs is odd too. Mine is totally steady. Sounds like a vacuum lead. I can't imagine that the O2 eliminators would do that.

Good Luck!

 

Check out VFRD thread on Starter Valve Synchronization. Might be worth taking it to someone to do.

 

A PC5 and dyno tune has been life-changing on my 04 VFR 800