Thursday, July 18, 2013


Unfortunately I don't really have any pictures to show this process.  I first took apart the carbs and cleaned the jets with carb cleaner.  Then I sync-ed them manually.  I took off the air filters(or box) and then having my brother slowly open the throttle, I held my fingers on the slides as they raised up.  Do this as they open and then as they close.  My one carb needed a small adjustment by turning the nut on the top of the carb where the gas comes in.  It takes a while to dial it in, but getting the settings on the air mix and fuel screws are very important.  Lots of trial and error. My advice is to start from the factory settings and then slowly adjust either way until it's a strong idle.  I ended up at (roughly)1 1/2 air screw and 3 1/4 on the fuel screw. 
The bike was dying randomly for me and sometimes it would dump gas out of one of the bowl overflow hoses.  This was from 2 things.
1. I determined that the float had a tiny hole in it allowing it to fill with gas and never float up enough to shut off the gas coming into the bowl.  I tried many remedies, jb weld, soldering, silicon, etc.  Nothing worked long term.  I broke down and bought a new one on ebay from Thailand.  Works great now.
2. The previous owner had put aftermarket cone air filters instead of the stock airbox.  Surprisingly they were choking the carbs and it wasn't getting enough air. I determined this by inspecting the spark plugs and trying the bike with the air filters off.  I put on some uni foam filters and they work perfect.

Then of course, I had to reset the air and fuel screws again.
I also experimented with different needle settings. Moving the needle up would nearly kill the bike at first, but then have strong acceleration. Lowering the needle seemed to be bad all around. So, the middle setting ended up being the best for my bike.  The carbs take some patience, but it was very rewarding to work it all out on my own. Just don't go to far before you have them dialed in.  I've pushed the bike back to the garage many times.

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