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Got the popping figured out but now when I try and get on the throttle the bike wants to die and has no power. It idles fine. If I don't give it anymore than 1/3 throttle it is fine. Did have some fuel on the diaphragms when I took the carbs a part last time. Any insight would be appreciated.

Thanks
I had my dirt bike (TTR 250) doing exactly the same thing - turned out the holes in the emulsion tube (that the needle sits in) were blocked - several of the lower ones. It would idle fine, and run OK at a low throttle setting - but give it a bit more, and it would splutter and cough - but would pick up with full throttle. Cleaned out the holes (they're real small), and it was back to good again.

Not saying that that IS your problem - but at least it gives you somewhere to start looking.
 

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Discussion Starter #122
Thanks for the input Steve. I replaced the emulsion tubes when I did the carb rebuild so if they are already going bad I am going to be pi$$ed. I think I found the problem though.

I knew from my experience working with older cars and from what I have found in the forums that I more then likely have a vacuum leak or fuel starvation. In the midst of my preparations for hari kiri I decided to take the carbs off again and see if something had worked its way into the fuel line. When I went to pull them off the intake tubes I noticed a gap between the diaphragm covers and the little o-ring that sits back there.


For starters I did notice the o-rings that I put in there are too small and the covers are a little warped. Since both carbs are acting the same way and both have this gap I am pretty sure this is the problem.
 

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That could be it. Particularly if they don't start to leak/fail until some decent vacuum builds up (ie as the revs increase).
 

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Discussion Starter #124
That was it. Put some thicker o-rings in there and the problem is gone. It sill spits a little bit around the 3k RPM range though. I think 3k RPM is right around where the timing advance starts to kick in. Fine tuning the crabs (fuel/air, synching...) and the timing should take care of this. I need to get to know the Ignitech unit I put in. It is still running the default config.
 
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