Need4Speed Posted September 6, 2004 Share Posted September 6, 2004 The bike has not been running right for some time now, I paid to have the carbs tanked and adjusted and it ran better but not right. I have also messed with them and still no better. They don't seem to respond to adjustments like they did a few years ago. Symptoms: Won't idle below 2K RPM Starts ok, might even idle for the first few minutes Won't idle after warming up Runs ok above 2K, snaps clean anywhere above 2K (not smoth like it used to) Carbs are clean (jets very clean) Used to run real strong, clean A number of years ago I balanced the carbs and idle, easy job Now doesn't run good enough, vacuum jumps all over the place Slight poping sound appears through the carbs Is this a symptom of the bike needing a valve adjust? Link to comment Share on other sites More sharing options...
Moderator YamaHead Posted September 6, 2004 Moderator Share Posted September 6, 2004 :hi aboard Need4speed If your carbs are clean & balanced, then the valve adjust culprit you suggest would be obvious, as you'd be hearing quite a bit of noise from the cylinder head whilst riding it :wink: TBH....from those symptoms you described.....you might want to have a look @ your ignition timing next :wink: Hope this helps.....& keep us posted Link to comment Share on other sites More sharing options...
jimjam Posted September 8, 2004 Share Posted September 8, 2004 Sounds like a sticky choke The engine won't run on idle when hot. Classic choke problem. Link to comment Share on other sites More sharing options...
Bazz Posted September 9, 2004 Share Posted September 9, 2004 Hmmm, could be both! If your valve clearances aren't right or worse still a bent or sticking stem you will get similar running problems. I'd get the valves checked for sure, if only for piece of mind. Also check that the choke is releasing fully, and not sticking when closed. Link to comment Share on other sites More sharing options...
Need4Speed Posted September 11, 2004 Author Share Posted September 11, 2004 I don't think that it is the choke, it seems to run slightly better with the choke partly closed. Something just isn't right, and I no longer think its the carbs. What are the symptoms of needing a valve adjust? Link to comment Share on other sites More sharing options...
Bazz Posted September 11, 2004 Share Posted September 11, 2004 Pretty much the symptoms you started with mate, also any excessive top end rattle/ticking. Get it checked out before it does any real damage - if you drop a valve you're looking at a complete top-end rebuild. Better to spend a few quid now rather than loads more later! Link to comment Share on other sites More sharing options...
Need4Speed Posted September 12, 2004 Author Share Posted September 12, 2004 I just took off the radiater and cam cover, the left end intake valve was just about in the fully closed position and I can't get a 0.006 feeler gauge into it. I stuff I have seen indicates to measure the gap and then select another shim as needed. I have heard that the valve seat is what wears and in exreme cases the gap goes to zero (i.e. the valve doesn't qiute seat), and that when warn they can be even farther from seating. If this is the case how do I determine what shim size to use? The bike only has 8000 miles on it. Do I just select another shim 0.008 smaller and measure a second time? I don't want to have to buy shims twice..... Link to comment Share on other sites More sharing options...
Need4Speed Posted November 20, 2004 Author Share Posted November 20, 2004 Anyone have any valve shims for a 5 valve genesis engine or know where I can pick up a starter kit? Link to comment Share on other sites More sharing options...
tdr man Posted May 1, 2006 Share Posted May 1, 2006 Anyone have any valve shims for a 5 valve genesis engine or know where I can pick up a starter kit? make sure your inlet manifold gasket isnt broken as it would suck in air resulting in your symptoms.is it the same in the wet. Link to comment Share on other sites More sharing options...
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