HOOFING Posted May 9, 2016 #1 Posted May 9, 2016 i recently bought this bike it had been sitting for a year, and took it on its first run about 200 miles.it did very well.every now and then during tripit would act like it was loading up and popping slightly,went on another shorter ride and it did a little worse then this week went on a short run and it did horrible.exhaust popping lack power on high end. changed plugs and cleaned carbs does this sound like a timing issue and if it is where do i start? any imput is appreciated
bongobobny Posted May 9, 2016 #2 Posted May 9, 2016 Well, electrical timing is not adjustable, it is an internal part of the TCI. When cold, start the bike and CAREFULLY feel all 4 exhaust pipes for heating up, this will help determine if it is firing on all 4 or not, and WHICH cylinder to troubleshoot...
bongobobny Posted May 9, 2016 #4 Posted May 9, 2016 OK how did you clean carbs?? They are a pretty complex part with different "circuits" depending on conditions. You may have a defective Throttle Position Sensor (TPS). I'm not real familiar with the early Stars but I think they used as TPS on the pre "Venture" Stars... You troubleshoot the TPS with an ohmeter across the connector pins without the bike running. As you twist the throttle, the resistance should change linerally and smoothly, not erratically.
bongobobny Posted May 9, 2016 #5 Posted May 9, 2016 Another possibility is you have a vacuum leak somewhere... Also, when is the last time the carburetors were "sync'ed?"
HOOFING Posted May 9, 2016 Author #6 Posted May 9, 2016 we took them apart and cleaned with carb cleaner, and plolished slides and needle jets...dont know when they were synced last. and checked for vacuum leaks.wahat i dont understand is the progression of the problem if it is carb related
bongobobny Posted May 9, 2016 #7 Posted May 9, 2016 Well, it is a possibility that with the carb cleaner it loosened a piece or two of crud and now it is partially or completely clogging a jet or passageway or something. Because you stated it runs great at idle I'm kind of doubting it's an electrical issue unless the TPS, if indeed the '96 has one, has gone south, which WILL effect the ignition advance. If you take off the air box, can you see how the plungers "Dance?" They should all open and close pretty much in unison... This may be a little "out there" but how about your air cleaners?? If they get plugged up it could be starving the carbs for air. Also, along those lines, these bikes DO NOT run right with the air cleaners removed, i.e. the air boxes open... With the slides, also check the rubber diaphragms for pinholes, even the slightest hole can play havoc! Check out how the carbs react physically to throttle twisting and get back to us! Hopefully someone with more experience with the '96 - '01 will chime in. I do know the carbs are the smaller 28mm and bolt different than the RSV carbs.
HOOFING Posted May 9, 2016 Author #8 Posted May 9, 2016 yes it does have a tps. we had the air box off and and watched the plungers dance.i guess the tps is the next logical place to check
HOOFING Posted May 28, 2016 Author #9 Posted May 28, 2016 ok so took the bike out ran 80 miles did good occasional pop here and there but overall strong,coming back had rain and it did terrible popping and backfiring if these carbs mount upside down how would this effect this cosidering the gas tank covers the air box
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now