Flat spot in acceleration on '80 GS750

[KnuckleBuster]

I just got done cleaning and rebuilding the carbs. Put 'em on the bike and Synched the carbs. Timing is perfect.

You can accelerate pretty well up into 5th, but if you're in 4th or 5th and slow down (for a curve let's say) and try to accelerate quickly, the power flattens out for a few seconds, then kicks back in - almost like turbo lag.

My guess is that it's running lean, but how do you fix that in the higher RPM range?

Bike is 100% stock with airbox, filter, pipes.

Thanks,
Jay

[fastpakr]

What engine speeds are you talking about?

[KnuckleBuster]

Well, that's where we have an issue - the tach isn't working. Figure around 3000 RPM. If you're doing 55-60 and slow for a curve to say 45-50 and try to accelerate through it, it bogs down.

It almost seems like the needle needs to be moved up a little, but that can't be done, right?

[KnuckleBuster]

Well, I fixed a couple of problems.

I took the tach apart and smoothed out a lump of lubricant that had oozed to the bottom of the wheel, thus halting its operation - now that works.

After a quick test drive the other night, I found that the bike would die at WOT and just go slower and slower, once in a while lurching forward a little, like it was starving for fuel, not running lean.

I took a look at the fuel line (someone had installed a GM fuel filter inline) and noticed a very small kink. I shortened the line and all problems are gone. It runs GREAT!

[KEITH KRAUSE]

Glad it was a simple fix. Thanks for sharing.