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Discussion Starter · #1 ·
Ok so I bent the intake valve on my 110cc took it apart fixed it. But I forgot to mark what postion everything was at. So now I'm at a draw... I have the pistion at tdc, cam sproket at tdc 9 o clock but in what position should the camshaft be>? Right now when its at tdc its chillin on the top of the lobes, like about to open intake, if I spin it a lil past tdc the intake opens
 

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That chain times the crank to the camshaft. Both valves should be closed at TDC compression stroke. The intake should open around BDC at the end of the exhaust stroke somewhere, and the exhaust around BDC after the power stroke. Remember the engine turns over 2 times and the cam once every cycle. If you let the chain drop off the gear on the crank you have to go thru everything now. Start with the crank on TDC, put both lobes pointing up on the cam when the chain goes back on the gear. Think the cam gear only goes on one way, but there are marks, and timing marks under the oval plate w/ 2 screws on the left engine case.
 

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Discussion Starter · #3 ·
yea i get what your saying. so i got everything at tdc, the lobes should be pointing up? like its literally about to open intake if i crank it anymore. is this right?
 

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Sorry, I goofed up, been working on 2 strokes too long,lol. The lobes should be pointed Down at the head and both rockers should be hitting on the back side, or bottom of the cam lobes somewhere at TDC compression. I believe the coils on my 750 Honda fired at TDC on the exhaust stroke too. After the bottom of the compression stroke the exhaust valve should start to open next.
 

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Discussion Starter · #6 ·
Sorry, I goofed up, been working on 2 strokes too long,lol. The lobes should be pointed Down at the head and both rockers should be hitting on the back side, or bottom of the cam lobes somewhere at TDC compression. I believe the coils on my 750 Honda fired at TDC on the exhaust stroke too. After the bottom of the compression stroke the exhaust valve should start to open next.
yea i got it working. i found out i wasn't getting enough compression so the valve was still bent. i fixed it and the timing. so all is good now. bikes running stronger than ever
 

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Git R Dun PBracer
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Great job. :)
 
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