Slow acceleration

The bike had not run in sometime. Rusty tank, leaks, and neglect. I've spent a few months bring it back. Cleaned tank and repaired leaks, rebuilt petcock, replaced one points and set timing, carbs cleaned and new gaskets installed, filter cleaned and new oil added. Synced throttle cables, set idle and air fuel mixture, etc..

The engine idles smoothly at 1100. However, when I accelerate each cylinder individual the left engine responds slower than the right. I get a quick and immediate on the right side but a hesitation and then slower response on the left. Using the hand grip throttle to bring up both engines at the same time the response seems normal. All this is being done with the bike on the center stand. No load.

Any ideas?

Nick, I have to assume you're talking about the CB350 you mentioned in your introduction because you did not say above. You've also basically outlined what you've done to the bike above too, but only in the simplest of terms so we do not know any details about the extent of carb cleaning required to get the bike running. This makes it less likely that anyone here will know the answer to your question since we haven't been able to follow along on anything you've done so far. And since we haven't seen pictures of the bike either, we don't know how you have it set up. Stock air filters? Stock exhaust? When you cleaned the carbs did you replace the diaphragms? If you dunked the carbs in any type of chem dip, did you also replace and oil the throttle shafts seals afterward? Did you use carb kits and replace all the brass parts with the new ones from the kits? What is the float level set at? What condition are the rubber intake boots?

nick said:

Any ideas?

Click to expand...

Have you adjusted the valves and checked compression yet?

Have you set the timing with a strobe timing light? Checked the advance operation? Are both carbs the exact same model? Are both exhaust systems clear and from the same model bike?

I’d first suspect either a hole in the diaphragm or a partially clogged idle/slow speed circuit in the carb, but it could be a lot of other things, too.