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Discussion Starter #1
I just rebuilt a top end on my buddy's 1972 CB350, new rings, valves lapped and cylinders honed... Got everything back together and timed perfect. The engine fired right up and idles just fine, blip the throttle and the motor sounds great. But when you hold the throttle at 3500rpm it starts to bog down. After trouble shooting the carbs, coil wires & plug caps we replaced the caps and cleaned the carbs thoroughly. That fixed maybe 75% of the problem but it still bogs down in the midrange. I'm stumped and can't seem to figure out why it idles great, blips to 3/4 throttle are clean & crisp, but when you hold the throttle it bogs down.... Any help is greatly appreciated..

Thanks,

Chad
 

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Checked the advance with the strobe light and it advances fine with in the two hash marks. It's running pod filters and pretty much open exhausts. The carbs have 105's in the main's and 68's for the idle jets, I think it's not getting enough fuel in mid & high range rpm's.... Any help or suggestions????
 

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Oldyota said:
But when you hold the throttle at 3500rpm it starts to bog down.
Chad
When it starts to do that, fiddle with the choke lever a bit - if it helps to have a little choke, you're lean in that "range". If not it's likely rich in that band.
Really important to "read" the spark plugs now.
Pod filters usually require jet/needle tweaking on a 350...with the Uni's, not so much so.
 

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Just wanted to give the update....

Pulled the carbs again and completely them tore down.. And there was corrosion in the primary tube stopping the airflow to the main jet.... She runs like a top now...... Thanks for your help...
 

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Hey, that's good news. Thanks, especially, for the update re: the carbs.

It's always hard while Internet troubleshooting when someone says "we did X, that's not it". One always wonders, did they really do X, or did they do X correctly? Or is this something else, and I really can learn something here, too...

I'm not bustin' on you, and I don't mean to sound like it. I'm just using you as a current example.

Thanks for the update.
 
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