Question about 2000 Yamaha DT 125 R

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No power at low revs but works a treat at higher revs.

Hi there. Hope you can help me, bit of a novice when it comes to understanding the workings of an engine but i have aquired an 87 tzr 125. Had to replace the head and bottom end bearings but otherwise a nice bike. Starts first kick with choke out, then idles very smoothly with choke off. Problem is there is no power at all at low revs, blip the clutch a little and the power valve kicks in and the front wheel lifts off the ground all the way to 3rd gear. On flat ground i can set off ok but drop into 2nd and it wants to die until the revs build (only when clutch blipped). Please help, its hard work riding it right now... Many thanks. Greg

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  • jordonetienn Feb 12, 2009

    im not sure if my power valve is working? how will i know?


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Hi mate it seems your powervalve is turned up fully, It can give u power on top end ,middle,and bottom end of revs.With it being a 87 a manual valve you will have to take off your exghust off.Now take a look into your engine through your exghust manifold and turn the power valve round ,you will see the hole in which the burnt gases escapre gets bigger or smaller by adjusting this gap you will find the perfect riding style for you (agressave or plesant ) remember to tighten all nuts up ,as you dont want your valve spinning round cus it will shread your piston and rings to death. hope this works

Posted on Jan 23, 2009

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Maybe its your carburetor it might need adjusting.

Posted on Jan 14, 2009

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