Originally Posted by
Roelof
The problem with cranktimings with your crank size (12mm?) is that about 0.1mm shaving of the edge of the crankshaft is equal to 1 degree. Ofcourse you can remove something visable but there is a chance it will be too much.
That is why those pictures with positions does not tell a thing.... (athough I suspect the timing is very mild and has some room to enlarge)
The most simple thing to do is use a dremel and a caliper.
Take a caliper and measure the diameter of the crankshaft on the opening of the crankshaft. That is probably arround 9 to 10mm
Use a dremel to touch one edge at the opening so the diameter will be 0.05mm smaller. Do the same on the other edge so the total will be 0.1mm smaller.
In that way you have changed the opening and closing with both 1 degree, it should be noticeable.
Here a pic how to meassure
http://www.euronet.nl/users/tooms/ftp/meten_krukas.JPG
Thanks, I'll take the appropriate measurements. It sounds like the diamond-coated hand files I own will come in handy for this project.
Would I want to change the leading edge of the intake port, though? I'm looking for more top-end, not more bottom-end. I thought top-end was adjusted by changing the trailing edge of the intake port?
Also, how do I determine how much adjustment is actually useful vs. how much will cause damage?