Mikuni Carburetor Problem

[jesse]

I recently started an xs650 chopper project. The parts bike that I am using is a 78 or 79 I believe (the serial number is 2F0-207XXX).

The problem that I am having is that when I allow gas to go to the carburetor it appears that gas is flowing out of the main and pilot jet holes. When I look into the holes it does not appear that there is anything down there. Should I be able to see a flat head slot?

Also I took apart the carburetor and one of the diaphragms seems to have a hole in it. I can only assume this a pretty big problem.

Does anyone else know of any other common problems with these carburetors that warrants checking?

Thanks

 

[650Skull]

An intro and description of your bike goes a long way in others helping you diagnosing your problems

Welcome.

Go to the Tech menu, (top of each page) and read up on Carb's. The more you learn the easier it will be to understand what members are trying to explain to you.

Yes the hole in the diaphragm is a major concern and needs to be replaced. There is a guy, ( JBM Industries ), that makes replacement carb diaphragms and they are ethanol proof and a reasonable price

Skull

 

[BigJimmyW13]

An intro and description of your bike goes a long way in others helping you diagnosing your problems

Welcome.

Go to the Tech menu, (top of each page) and read up on Carb's. The more you learn the easier it will be to understand what members are trying to explain to you.

Yes the hole in the diaphragm is a major concern and needs to be replaced. There is a guy, ( JBM Industries ), that makes replacement carb diaphragms and they are ethanol proof and a reasonable price

Skull

+1

 

[bluebikerblan]

Here's a shot of your BS 38 bowl with labels as provided by TRG The - Retired Gentleman, a site stalwart with oak leaf clusters, that can help answer your questions about the jets in the "holes"

The rest is up to you re the carbs and how much you're willing to study and confirm with practice. Here's a vital carb guide, the authors grizld1 and 5twins, frequent the site also.

http://www.amckayltd.com/carbguide.pdf

BOL, Blue