Maintenance & Technical > KX500 Original

Best timing for '90 k5?

<< < (3/3)

martinfan30:

--- Quote from: Motorrad on October 11, 2010, 04:29:24 AM ---
--- Quote from: martinfan30 on October 11, 2010, 02:01:04 AM ---I just buttoned up my 500's engine yesterday. I am going with a gnarly desert pipe, which from what I read is great bottom to mid, and smooths out the top hit.

So my logic was run it closer to the right hand mark (slightly advanced) to help keep the top end .

Am I pissing in the wind here with this thought?

--- End quote ---

Gnarly desert is mid to top.   (same as a fatty).   

Your thinking of gnarly woods pipe



--- End quote ---

Oh ok... So if I'm advanced on my timing, then this pipe should work well everywhere...

kwakman:
Right.If you are using the desert pipe, you would be best advised to move it to the right hand mark,( anti clockwise).Your train of thought is correct, but what retarding(R hand mark) does is moves the combustion process back, which enables more heat to pass into the pipe, raising the temp.The increase in temp means the waves in the pipe can move faster and gives a more pronounced effect in the top end of the 'band.
OR, by advancing the ignition, (L hand mark), you give the cylinder more time to have the mixture burn enabling a greater pressure rise in the cylinder, but having increased the spark lead time, you get increased pumping losses at high rpm.
If you move yours left, you will not have pipe and ignition in sync, and will lose some of the benefit of having the desert pipe. As long as you stay within the marks, have a play and then ride it and see what suits you best. Ultimately though, if you want fat bottom end, I would change the pipe to a Gnarley woods pipe. part no 020055.HTH.K.

martinfan30:

--- Quote from: kwakman on October 14, 2010, 10:18:49 PM ---Right.If you are using the desert pipe, you would be best advised to move it to the right hand mark,( anti clockwise).Your train of thought is correct, but what retarding(R hand mark) does is moves the combustion process back, which enables more heat to pass into the pipe, raising the temp.The increase in temp means the waves in the pipe can move faster and gives a more pronounced effect in the top end of the 'band.
OR, by advancing the ignition, (L hand mark), you give the cylinder more time to have the mixture burn enabling a greater pressure rise in the cylinder, but having increased the spark lead time, you get increased pumping losses at high rpm.
If you move yours left, you will not have pipe and ignition in sync, and will lose some of the benefit of having the desert pipe. As long as you stay within the marks, have a play and then ride it and see what suits you best. Ultimately though, if you want fat bottom end, I would change the pipe to a Gnarley woods pipe. part no 020055.HTH.K.

--- End quote ---

Thank you for the great explanation! I want the mid to top the dez pipe allows. I just want to help where the pipe doesn't by changing the ignition timing.

THanks!!!

Navigation

[0] Message Index

[*] Previous page