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XR4 BSR42 no start

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I have a ground up completely rebuilt XR4 sitting in the garage modded with a bsr42. I finished the rebuild last fall. I started it twice and it ran before winter storage. Went to start it last Fri. and it will not fire. I have good spark and air but, I think I'm not getting enough fuel now. I have already torn the carb down and cleaned it. Do any of the members here know how to troubleshoot a no start with the Mikuni ?

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When you stored it for the winter, did you drain the float bowl?

When you cleaned the carb, did that include removing the fuel screw and related parts and spraying out that passage? Most of the time when the bike was put up running and won't run later, that's the problem. Just a drop of fuel (ethanol) left in that passage while stored will turn to varnish and gum up that tiny passage.

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Yes, I drained the bowl at storage and recently took apart the carb and inspected / blew out all of the jets trying to troubleshoot the no start. I didn't see any varnish and rechecked the float height at 13 - 14mm. Maybe I have an idle setting problem ? How far in should I set the idle screw ? I also noticed some fuel overflow and have read that it is a common issue with these carbs. Should I adjust the float height lower ?

 

Thanks guys

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What has your starting procedure been?

The first time I went to start my 400 with the BSR42, I think I had to kick it 100 times.  Choke on, choke off, no throttle, tiny throttle, WOT throttle, nothing would work.

For me, it wound up that we had the idle screw adjusted too far open.  Don't know why exactly that caused complete no-start, but it absolutely would not crank.  Once we got that about right, it fired right up.  Now that it's all dialed in, it has started on the 1st or 2nd kick, hot or cold, every time I've cranked it.

Don't know that this is your problem, but might be something to check.

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Thanks, that gives me an idea of where to set it. I don't remember where it was last fall when it fired up. I should of looked before tearing everything apart.

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On 4/26/2017 at 2:37 PM, sneaky98gt said:

What has your starting procedure been?

The first time I went to start my 400 with the BSR42, I think I had to kick it 100 times.  Choke on, choke off, no throttle, tiny throttle, WOT throttle, nothing would work.

For me, it wound up that we had the idle screw adjusted too far open.  Don't know why exactly that caused complete no-start, but it absolutely would not crank.  Once we got that about right, it fired right up.  Now that it's all dialed in, it has started on the 1st or 2nd kick, hot or cold, every time I've cranked it.

Don't know that this is your problem, but might be something to check.

Sent a PM.

Edited by nomad221

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