Topic: weird idle/takeoff issues

[MetalHead550]

My bike was in a collection and had only 10k when I bought it.  It had 1000 miles put on it from 83 to 2003 at which point I began riding the hell out of it, putting nearly 7k on it.  I dont beleive the bike has had a tune up or any carb adjustments since new so is it safe to say I pretty much broke it in?  Heres the problem.  I began to notice valve chatter recently and naturally adjusted my valves and cam chain following my Clymer to a T.  However I made the mistake of using a socket instead of an open ended wrench when I loosened the cam tensioner lock nut so I never saw if it adjusted itself as the directions indicate.  The bike runs very smooth with plenty of power at speed however at warm up the carbs can be heard to pop or quickly suck.  Once it warms up and can idle it seems ok but for a slight surge every now and then.  When the bike has been ridden for a while and is hot this becomes worse.  while idling it will rev somewhat as though I were giving it a bit of throttle.  Of course I'm assuming my timiing is off.  Can adjusting the valves and not properly adjusting cam tention throw off the timing?  Also take offs are a bit rougher and require more throttle than before and sometimes has a small backfire.

[Ibsen]

From the way you describe it, it seems to be running lean.
The first thing I would look for is if there is any air leaks.

[Quail "Owner of the comfortable k8"]

Yes adjusting the valves with a slack chain can affect valve adjustment.  If the chain is slack and the cam lob has not moved to its complete no lift postion you can adjust your valves open to far.  It would take a lot of slack though.  I just put a small shaft into the hole of the tensioner and then I can feel the tensioner shaft move if there is any slack.  I learned on this site to recheck it after you start it and was suprised to feel  it adjust even more.  Resist the temptation to press in on the tensioner rod and over tighten the chain.  A tight chain is an unhappy chain. On another note the noise you describe as valve clatter.  if it is mechanical noise it may be the chain or the excessive valve lash if it is a "ping" like the sound cheap or old gas gives it is not.  The popping back sounds like igntion timing or a failing coil, but valves to tight will pop into the intake also but not off and on.  Thats my .02.  be sure to post the answer.   

[MetalHead550]

Well Im gonna dig into it tomarrow and recheck my valve clearances.  Should I adjust the cam chain tension before I do the valves this time.  It makes sense to do it before doing the valves but I did it afterward last time for lack of knowing any better.  And that was the first time it had been done in about 7k miles so the slack may have been significant enough to throw it off.  Ill go ahead and check/set the timing if need be.  All the carb boots are good and tight but Ill check the manifold for leaks.  I do need to go through the carbs eventually as I have a float that will stick once in a while and the fact that the carbs havnt been adjusted, probably since new, may contribute to less than perfect running conditions.  This bike had it easy and sat for a long time and went strait to me riding it damn near everyday and sometimes pretty hard so I expect it to need some tuning.  One more thing: when I hold my hand behind each exhaust pipe they all have the same pressure except the #4 which seems week.  Low compression? Carb out of wack?  Plugs look good.

[MetalHead550]

Update.  This time I adjusted the cam chain before looking at the valve adjustments.  Didnt move much, but upon checking my valve clearances I found a couple to be set too tight.  Readjusted the valves but made an incredibly stupid mistake.  I used a long socket wrench to remove the tappet covers and while putting them back on I snugged one down not thinking about how much leverage I had and, POP, I cracked the damn threads away from the cover.  Thats why they have torque specs huh?  Not a big deal but now I have to wait 3-5 days for a new one and we have perfect riding weather right now.  Oh well.  Did a temp. fix on the tappet cover with JB weld to see how it ran.   Smooth as silk. Cool.  Except for the oil spewing out of the tappet cover! HA!