Misfire when cold

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tagordon
Posts: 32
Joined: Sat Oct 16, 2010 9:44 pm
Location: Salt Lake City, Utah

Re: Misfire when cold

Post by tagordon »

Otto, I don't think it's a prob w ignition. As MS mentioned ingnitions probs usually get worse as the engine warms. But removing the plugs is a good idea, you can check the color of the insulator. Make note of which plug comes out of which side. And see if they are both the same color. Have you checked the carb float level?
Motorcycles Cost Less Than Psychiatrists
Jean
Posts: 1100
Joined: Wed Aug 18, 2010 7:43 am

Re: Misfire when cold

Post by Jean »

Did it just start doing this? I noticed you have individual air filters on your carbs. This usually also needs a richer mixture for your carbs. Maybe the intermediate carb port is clogged, or if it just started when you changed the air filters, the jetting isn't right.
One other thing. How long have the diaphragms been in service? 8-10 years? Change them.
Clemson, SC
R100s, R75/5
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tagordon
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Joined: Sat Oct 16, 2010 9:44 pm
Location: Salt Lake City, Utah

Re: Misfire when cold

Post by tagordon »

Jean, the carbeurator image was of my bike not Roadrocket's.
I wonder if he has done any further diagnostics. He seemed inclined to replace some parts.
Motorcycles Cost Less Than Psychiatrists
Jean
Posts: 1100
Joined: Wed Aug 18, 2010 7:43 am

Re: Misfire when cold

Post by Jean »

oh.

replacing parts helter-skelter usually doesn't work out well. Only the parts vendors come out on top.
It's been a while...wonder what is happening?
Clemson, SC
R100s, R75/5
Dan in IL
Posts: 25
Joined: Thu Aug 25, 2011 8:16 am

Re: Misfire when cold

Post by Dan in IL »

Thank you Tagordon! That was a great tip about the vent hole. My R100RT has never run right when cold. I poked a wire in those vent holes and found some resistance on the right side that I managed to poke through. That seemed to make the difference!!

I’ve had those fuel enrichners apart twice trying to find the problem but somehow never noticed those holes.
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tagordon
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Joined: Sat Oct 16, 2010 9:44 pm
Location: Salt Lake City, Utah

Re: Misfire when cold

Post by tagordon »

Your welcome, Dan.
Glad it helped.
Motorcycles Cost Less Than Psychiatrists
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