Author Topic: Sticking throttle valve (CB175)  (Read 1573 times)

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Offline yourfirekiller

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Sticking throttle valve (CB175)
« on: May 12, 2013, 05:14:50 PM »
Hi all,

I picked up a non-running CB175 and I've gotten it to fire up, and run, but it revs super high because the left carb is acting up.

When I close the throttle, the left side throttle valve sticks open about halfway. When I pull the top of the carb off, I can push the valve closed with a screwdriver, but it won't fully close on its own, it feels like it's sticking.

I've pulled the carbs off and cleaned them, and even did some light polishing with a dremel to remove any gunk that may be obstructing the throttle valve chamber, but maybe I didn't do a good enough job?

Any help would be appreciated!

Offline grcamna2

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Re: Sticking throttle valve (CB175)
« Reply #1 on: May 20, 2013, 03:39:34 PM »
I think you should look at your twist grip,throttle cables(especially the junction where they go from 2 into 1..),etc.
75' CB400F/'bunch o' parts' & 81' CB125S modded to a 'CB200S'
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Offline Old Scrambler

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Re: Sticking throttle valve (CB175)
« Reply #2 on: May 24, 2013, 06:42:59 AM »
Its somewhat common for the slide to stick after a bike has been sitting.  Yes, check the cable. Also, the carb-body may be warped.......usually the result of over-tightening the manifold flanges.........or just old fuel deposits.  Look for marks on the slide and try to match the location with the inside of the body.......then emmory-cloth both for a smooth finish. On re-assembly, apply some misting-oil or graphite-spray.
Dennis in Wisconsin
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