Keihin Woes

[sealdoggy04]

Ever get on your Keihin carbureted bike twist the throttle and the bike seem anemic like something sucked the life out of your engine.

This has happened to me a couple of times, so I thought that it pertinent to share my findings.

If this happens to you, the bike fires up fine you get her out of the driveway and crack the throttle and you get a third of the power you normaly get, then you just might have a torn vaccuum diaphram.

Lift the tank up, take off the top of the carburetor and pull out the diaphram assembly , check around the lip of the diaphram, there you will probably find a small tear or hole.

Modern gasoline aditives play havoc on the rubber diaphram, she will go south sooner or later so be aware of the symtoms descibed above.

The part is aprox $50 out the door and can be changed out in less than 30 minutes.

Be super careful when you put it back in that it's not pinched when you put the top back on.

Steve

[Dave63]

Originally Posted by sealdoggy04

Ever get on your Keihin carbureted bike twist the throttle and the bike seem anemic like something sucked the life out of you engine.

This has happened to me a couple of times, so I thought that it pertinent to share my findings.

If this happens to you, the bike fires up fine you get her out of the driveway and crack the throttle and you get a third of the power you normaly get, then you just might have a torn vaccuum diaphram.

Lift the tank up, take off the top of the carburetor and pull out the diaphram assembly , check around the lip of the diaphram, there you will probably find a small tear or hole.

Modern gasoline aditives play havoc on the rubber diaphram, she will go south sooner or later so be aware of the symtoms descibed above.

The part is aprox $50 out the door and can be changed out in less than 30 minutes.

Be super careful when you put it back in that it's not pinched when you put the top back on.

Steve

Ethanol especially contributes to this. Older rubber will deteriorate with ethanol exposure.