I have a 98 vfr 800 that i recently purchased and am expiriencing some issues with the bike running lean
( backfiring on deceleration)
The bike has an old powercommander 2 in it and I am afraid that the map is not set correctly for the two brothers full exhaust that is instaled on bike.
I cant get the dang power commander to connect to my computer!!!!??!!!!
it has a 9 pin serial port
i have a usb converter plug but the computer still wont pick it up.
I would hate to have to buy a new 300 dollar power commander.
Please Help!
Also I am about to install a Barnett clutch kit on bike due to slipping at full throttle what else should i replace while im in there?
viffergyrl had a PCII on her bike that she removed due to poor performance at high altitudes. I considered trying it on my bike so did some research, and decided it's not worth screwing with. Both our bikes run fine with K&Ns, and slip-ons from below sea level to 10K feet. They have been de-PAIRed though. That made the decel backfiring go away 99%.
Can't think of anything else you should need to service behind the clutch cover.
[image: View Post]MBrane, on 01 April 2012 - 11:26 PM, said:
viffergyrl had a PCII on her bike that she removed due to poor performance at high altitudes. I considered trying it on my bike so did some research, and decided it's not worth screwing with. Both our bikes run fine with K&Ns, and slip-ons from below sea level to 10K feet. They have been de-PAIRed though. That made the decel backfiring go away 99%.
Can't think of anything else you should need to service behind the clutch cover. What is de-PAIRed?
A pair valve is a pollution control device that injects fresh air into the exhaust system which helps to combust any leftover fuel vapor in the exhaust system. De-pair simply means to disable this functionality. The result is usually less popping and smoother deceleration.
The UK's Bikers Oracle VFR forum has an excellent guide to the PAIR system and its problems here.
I have my 2000 800FiY stripped at the moment for its 32K service and have cleaned the PAIR reed valves and gubbins, fitted DIY plates on top, and removed the plumbing. I can't discuss the effects yet since three valves need reshimming, and the fork oil and shock changing, and .....
If you suspect the PCII or the map it's running, just unplug it. Most of the time I've had my '01 VFR800 (over 7 years), I've run it with the O2 sensor eliminators and no PCII. Actually runs better'n all the maps I've tried. If nothing else, taking the PCII out eliminates one of the factors in the "not running right" equation.
[image: View Post]enzed_viffer, on 04 April 2012 - 03:26 AM, said:
If you suspect the PCII or the map it's running, just unplug it. Most of the time I've had my '01 VFR800 (over 7 years), I've run it with the O2 sensor eliminators and no PCII. Actually runs better'n all the maps I've tried. If nothing else, taking the PCII out eliminates one of the factors in the "not running right" equation.
Funny, I was about to basically make the same post as the OP. Would unplugging it also resolve fuel usage issues? I'm only getting 33mpg on average on a very new (to me) '99 and am wondering if the PCII is the culprit.
[image: View Post]Mazaev, on 05 April 2012 - 08:13 AM, said:
Funny, I was about to basically make the same post as the OP. Would unplugging it also resolve fuel usage issues? I'm only getting 33mpg on average on a very new (to me) '99 and am wondering if the PCII is the culprit.
Could well be. Running without the PCII, the bike may be running lean, if anything, as it tends to run a bit hot. And it's by no means sucking up the juice.
End of thread · 12 posts recoveredWayback Machine snapshot 28 Jun 2012