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Old 06-15-2015, 06:46 PM
Slogger Slogger is offline
Motorized Bicycle Elite Member
Join Date: Sep 2014
Location: nohio
Posts: 499
Default Re: what did you do to your motorized bicycle today?

My bike uses the longer, offset manifold and is stock.
I'm doing battle with the screwy spraybar on a Dellorto SHA clone. It has this huge hole that is uncovered as you go past 3/4 throttle. Coincidentally the engine hits a rich blubbering trough right at 3/4 throttle. The lower hole is much larger than the carb jet and there is also an idle jet hole in the body.
The engine is geared so tall it will hit 30 @5700 rpm. No matter how much gas and air it gets this stock engine will never see 6500 rpm. I don't think the top hole is helping things.
I've been running a very small jet to keep it lean enough to wind out a little.

Today I went up a size on the jet and tried to solder the top hole shut. I did, but the solder was fouling the slide so it was picked off. Several attempts were made to flow it into the pipe, but it wouldn't do it right.
I mixed up a bit of JB weld and put a bit in the top hole. It's blocked. Forever. !

Now all the gas will have to draw through the slightly smaller mid range hole. I went up a jet size for insurance for the first test run tomorrow. (The JBW needs a little time.)

To fix a no-air-with-the-choke-on problem (it will hardly run with it on), I drilled out the choke plate air hole to 9/32". Can't hurt.

I'll find out tomorrow if the carb is now a paperweight, or not.

Havin some fun!
Buzz zzzzz zzz
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