TDC question

3 replies to this topic
  • yzrider

Posted January 27, 2001 - 02:26 PM


I read in MXA that it's a good idea to bring the piston to TDC after you shut it off, so it closes the valves. My question is how do you bring it to TDC ? Do you just need to kick the engine through to the hard spot and pull in the compression release lever and kick it through the additional 1/4 inch or ? Thanks for your help.

  • Boit

Posted January 27, 2001 - 03:02 PM


Once you get to that hard spot, you are at compression....all valves are closed, which is what you want. Stop there and you're good.

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  • Guest_Guest_*

Posted January 28, 2001 - 06:34 PM


A friend of mine made a good point on this subject. He said that our bikes generally stop at TDC when you kill them so making a point of doing this is not that big of an issue. Generally I think he is right.

  • Boit

Posted January 28, 2001 - 10:40 PM


Paul: Generally...that is what I have found. But, since I am a FANATIC about putting my engine at TDC EVERYTIME I kill the engine, I've discovered that it doesn't always end up at TDC. Apparently, sometimes, the piston hits the compression and then bounces back a few degrees of crank rotation so that you end up at somewhere between exhaust and compression. At 12.5:1 compression, there is quite a resistance if the inertia doesn't carry the piston thru compression. The compression really acts as a spring. I agree that MOST of the time, the piston ends up at TDC.

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