Acceleration Stutter

Hey all,

I imagine that there are posts about this already but without finding them quickly I figured i would post and get some opinions on this. My '83 XJ650 is my first bike and i love it 95% of the time. It runs great and has more then enough power for my first season or two. I noticed though that right when i hop on the throttle from a dead stop that the engine bogs down for half a second or a second before the bike takes off. It isnt a big deal except that when trying to go up a hill from a stop i will commonly stall it because of this and that, as most of us know when riding with other people is just embarrassing. Any opinions on what this may be? I have been getting varying opinions from other people; everything from a minor adjustment of the throttle cable to needing to tear the carbs off and rebuild them... please help!

 

Follow this thread - I'm having a similar issue.

http://xjbikes.com/Forums/viewtopic/t=3400.html

 

Could be caused by a few things, on that link he supplied. Look for the links under one of my inputs, that is 3 pictures of "print" actually, that explains tuning CV carbs.

If your floats are too low, your not siphoning the boost fuel quickly enough for accelerating. Your needle clip position can cause the same problem, as well as pin holes in your sliders rubber diaphram's. Check them with a back light. A thin film of silicon rubbed with your fingertip will fix them.
(I want to try a new spray rubber paint I recently found. I coated the bottom crossmember of 1 of my classic cars I'm working on, before setting the radiator down on it. It felt awesome, nearly turned the feel of the steel into a nice rubber seal.) Of thinking of this spray, I bet masking off the barrel to the slider and just spraying the diaphram it would make a perfect rubbery thin coat, instead of doing patch area's with silicon.

Print them, and read those tuning proceedures carefully, and the best thing I can ever tell anyone is really go out and pick some testing points like the write up talks about to REALLY find exactly where your problem is. So you can diagnose as closely as you can.

Do testing with partial throttle, from 2000 rpm cruise (like 3rd gear), then try full crank on.
Then go up to 4000 rpm and do it again.
Try to get going from a stop with little to half throttle, then half, then wack it.
Does it only stall on the Wack ? And will it do it just running the engine while sitting still. With no load on the engine will it still bog?

 

My issue turned out to be float levels. All good now!