Conrod queries!

[richardlw]

It may be possible to use a Raptor 660 con rod as well but I haven't looked into it closely . If it would work there is a bunch of heavy duty versions made to take a heck of a beating..

Based on my bits of research, the ProX XT600 Conrod P/N 03.2600 dimensions are:

Big End Diam = 43mm
Big end pin diameter = 35mm
Big End Conrod Thickness = 22mm
Gudgeon Pin End Diam = 22mm
Gudgeon Pin End Conrod Thickness = 22mm
Centre of Big End to Centre of Gudgeon length = 135.5

The Raptor 660 dimensions are (Pro X P/N 03.2660):

Big End Diam = 45mm
Big end pin diameter = 37mm
Big End Conrod Thickness = 22mm
Gudgeon Pin End Diam = 22mm
Gudgeon Pin End Conrod Thickness = 22mm
Centre of Big End to Centre of Gudgeon length = 136.5

http://www.pro-x.com/prox-connecting-ro ... sions-all/


So to sum it up, the Raptor 660 conrod center to center is 1mm longer, and the big end pin diameter is 2mm greater. So if you were to get a piston which has a 1mm lesser gudgeon pin to top of piston dimension, and could run a big end bearing with a 35mm internal diameter and a 45mm external diameter, it could work. But waaaaaaaaaaaaaaaaaaaaaaaay to much playing around for my liking!

On a side note, SKD and Koyo do roller pin bearings with an internal diameter of 35mm and external diameter of 45mm, but they come in 20mm and 30mm widths, not 22mm.


PS, as a side note, I take no responsibility if anyone makes decisions based on my research!

[xtrider]

Well I have a 600 currently that I put in a 11.5:1 piston plus used the small chamber head, plus shaved .015" off the head and cylinder surfaces combined so it's around 12 to 12.5:1 compression (208psi measured) , it's going on 6500-7000 miles with no issues other than it getting hot in the summer . So the conrod can take a bit of abuse thus far and mine had 12-15k miles on it already before doing the topend .

The bearings should really be the tighter tolerance versions , when you use the looser ones you run into the possibility of the balls skidding and more vibrations . I think many have used them but I try to use the better ones for the crank at least .


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