Throttle stuck on 1985 Yamaha QT50

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Throttle stuck on 1985 Yamaha QT50

Postby Talburt » Sun Jul 08, 2012 9:04 pm

Finally got my '85 QT50 moved to the Cities after I bought it about 15 years ago. It has been sitting for about 3 years, but after a little work its up and running again. The only problem is that the throttle is getting stuck all the way open. I've taken a look at the whole throttle system and everything seems to be working (throttle cable, junction box, carb section, etc) but it doesn't want to return after throttled back. I'm just OK, not amazing, when it comes to mechanics, so I'm not sure where to go from here. What are some common problems or hints that may help.

PS what is actually suppose to return the throttle after being pulled back?
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re: Throttle stuck on 1985 Yamaha QT50

Postby greenhead » Mon Jul 09, 2012 9:52 pm

Generally there is a spring in the top of the carb that returns the throttle, as well as the slide/needle in the carb. If the cable glides smooth in the housing, maybe it's just catching, try a little oil. It's almost thirty I'd replace the cables and maybe the controls, if you do replace the cable you'll probably want to grab a few knarps.
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re: Throttle stuck on 1985 Yamaha QT50

Postby xrongor » Tue Jul 17, 2012 11:48 pm

i have found that sometimes people screw the idle screw into the side of the slide on these things and it mucks it up and makes it sticky. try removing the slide and look for some damage caused by this screw, and take some fine sandpaper to it until the slide moves freely.
"In this world there's two kinds of people... Those with loaded guns, and those who dig." -- Blondie to Tuco
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re: Throttle stuck on 1985 Yamaha QT50

Postby roornwomps25 » Tue Sep 18, 2012 12:41 am

spring returns it but this happens a lot. i just use some bearing grease and get it all loose. new throttle.....? domino or maguras rock!
~RVA Rebel Rouser~
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