Bikes, Hints'n'Tips > FZS600 Fazer


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Soz , its a bit late but ive been doing a lot of head scratching  :z .
Ive just spent 3 days putting a new cam chain in,, around 75000 on old one so new one needed. No adjustment left on tensioner.  :'(
All seemed ok. Running in shed ,, didnt rev to much in shed as i wanted all engine parts to settle and oil to flow round.
Then off for wee run.
Out of drive and i noticed shutting off throttle and the revs were'nt dropping too quick. Not sticking open , just coming down slowly. :rolleyes
Just a short run and still the same at the end.
But i never touched the carbs,,, just took them off,,, and put them back on. Yep cables were off but when i put them on i checked the throttle and it was'nt sticking just usual nice spring back when you let go.  And again after run ,, throttle just snaps back but revs come down slow.
any ideas, cause i confuzzed :o

The likely cause is an air leak, from the carb rubbers.  They may not be seated properly around the carbs.  Check the 2 inner ones these can deform while refitting the carbs and you only need a slight leak.  Also check the balancing port caps are fully seated and not split.   

Yep Gnasher the two inner rubbers are a pain to get on.
YEP ..definitely air getting in. Had a small amount of brake cleaner in an aerosol and sprayed it around carbs and revs went up.
Now the weird bit  :\ . Put wee red extension pipe on spray so i could spray a bit more closer to each rubber,,, no real increase there. This was both rubbers on each carb. Then for no reason i sprayed over the top of each,,,,,  on the left carbs 1 & 2 no change.  On carb 4 small change.,,, Now carb 3 revs shot up  :eek .  So im still confuzzed but closer to problem but cant see what or why .

So why would i get air coming in from the top when again carbs were not touched. 
Well im part way there but will have to wait till weekend now.  Work always gets in the way.
Any ideas of why im getting result spraying more over the card extremely welcome.

Well im no further forward with problem :rolleyes .  Circlip on carb 3 wasnt too tight, gave it about a quarter turn. Apart from that couldnt find any air leak . So decided to put carb tune on and see what that showed.  To be honest they werent too bad. Carb 1 was about the most out but not by much.
So tried another wee run and just the same, shut throttle and it runs on.
Now ive been doing a but of thinking and yep i may have small air leak somewhere, but is this possible,,,
when lining up timing marks when putting head together which were right just before final tightening and torque ,,, have i just knocked it off slightly.
The reason im now thinking this is im sure i read someone putting head back on and when tightening down cams the two small end dot you line up moved off slightly,,, but i cant find the post to see his problem.
Im sure i didnt move the alternator off its mark,, but now begining to question it. 
If ive knocked timing off would it cause bike to not throttle down properly.   Any ideas.
Oh on short run i did open throttle a bit, and just as i thought it didnt want to pull , i wasnt expecting it too but just opened to see what would happen.

Incorrect valve timing will not give you the symptoms your saying the bike has.  Providing everything is working as it should, ie its starting, idling, pulling etc, slow at losing revs, it's an fuel/air problem. 

Take the carbs back off and check them over.  It's possible you've disturbed, damaged something.  Also recheck the pull/push throttle adjustment, incorrectly set can give you the very same symptoms.   



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