Carburetor Gurus. Won't rev.
I’ve got a problem on my ‘90 ZX7 project bike. I’m about sure it is a carburetion problem. The bike has been sitting for several years. I pulled the carbs apart and cleaned them very carefully according to a “How to” I found on a forum. Everything was checked. I was very thorough. I measured float levels, set the mixture screws and took apart and cleaned everything I could. Put them back on the bike, got them to prime and was finally able to fire the bike on it’s own gas. The bike cranks great and once warm enough to get off of the choke it idles good and smooth at about 13-1500. The problem is that it won’t take any gas.
From idle I can smoothly rev it up and it acts like it runs out of gas by about 4000 or I can blip the throttle and hold it and it may or may not make it to about 4500. Either way if I try to hold the higher rpm the bike dies. It cranks right back up though. The first time I blip the throttle and release it the revs go to about 4000 and fall quickly back down to idle. If I blip it again right after idle settles then it will only go to about 3000. Blip it again only to about 2200. The next blip kills the engine again. .If I let it idle a minute between blips it is okay and seems normal.
If it was an electrical problem I think it would happen at a certain rpm and not all over the place so it has got to be a fuel problem, right? The carbs seem to work okay on the pilot jets but it's my guess the main jets are not taking over. What could cause this? If the carbs just needed synching then I could see it rev roughly but stay running. This acts just like running out of gas, immediately after you touch the throttle. The bike does not smoke and does not smell rich.