Mild suging under light throttle

Hey gang -

I cleaned my carbs out this winter, although it was more of an inspection because they were amazingly clean inside.

Now I have a slight problem - more of an annoyance, really.

When I am running the bike under 3,500 rpms, I have a mild surging. I can feel the bike lunging a little bit under me, but if I crack the throttle any more than 1/4 open, it seems normal and accelerates fine.

It's not like a bucking, just a mild surge. My wife noticed it on our last ride and blamed me for not being smooth with the throttle.

Is this just a mild case of bad carb synchronization?

 

did it ever do it before? i have noticed mine does a similar thing at about the same rpm. i usually kept it around 3500 when riding around. now that i have changed the gears it does it around 3,000 , so i just stay above it. so i really don't know if its a problem or a characteristic of the bike due to the area of the powerband.

 

I would sync the carbs .... Im thinking of buying one of those tools....unless someone close by has one ??

 

3000RPM seems a bit high for carb synch to make much difference. On bikes that synch is way off...I have noticed popping at idle and at decel...when the "butterflys" are closed on their stops. Try opening the choke lever slightly when the surging is happening and see if your RPM then picks up. If it does...you got a lean spot at those RPM. If it makes it worse...you're either rich or you've an electrical issue.

 

My bike does pop a bunch on decel, I just attributed that to a TBR (straight through) slip-on with no carb adjustments.

It might have done this before, but I was too unfamiliar with the bike to notice.

If this helps, it almost seems to me like on carb is giving more fuel to it's respective cylinder at small part-throttle applications. Just feel a little more bang at a constant interval. It does go away at higher RPM's.

Again, it's not so significant that I would specifically tear into the bike to fix it, just wanted some ideas of what to check next winter when she's off the road again.

Keep the ideas coming!!!