accel pump timing

Can someone explain this to me? Do I need to have the bike running? I have removed the subframe, and am looking in the carb, but I do not see the spray.

Originally posted by astoch:

I have removed the subframe, and am looking in the carb, but I do not see the spray.

Twist the throttle and hold it open while looking into the carb through the air inlet. The accelerator pump jet sits just behind the slide at the bottom of the carb throat. It should squirt an easily visible stream of fuel away from you, into the motor, when you open the slide.

If not, something is wrong.

this may sound stupid...but make sure the gas is on whenever your trying to see if it squirts! LOL



I get my kicks on a 426!

Motoman393's MX Site

I had some problems with the accel pump, and it didn't work anymore. There was dirt in the accel pump, and it just stopped working. Cleaned it and made the BK mod. Works fine now. Maybe you have the same problem. Maybe it's worth checking.


I have been trying to find the BK mod in past posts without any luck, especially now. Could somebody please repost this information. I think a lot of people who have just found this site, including me, would benefit. Thanks Darrin

Ok, I see the stream now. Apparently the accel. pump will lose it's prime after a few strokes. Worked fine after I ran the bike for a bit. I've got the timing so the stream just misses the slide, but I did notice a light misting on the slide. Is this correct?

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