pinion shaft runout.

[guest]

Mike, have you noticed many problems concerning pinion shaft runout when installing gear drive cams? On some of the boards I read that people have terrible problems with it but when I ask my dealers tech he says it is very rare and he has not seen any out far enough to cause problems with gear drives. Your shop is a lot bigger so you would probably see more gear drive installs. thanks again for your help.

[Mike]

Pinions typ have .0015-.0025 runout (see as high as .006), so you have the pinion gear moving in and out releative to the rear cam primary gear by that amount. You have to fit the gears so that they are not too tight in one spot and nor too loose opposit so you have to compromise. This does not result in machanical failures but does make it (in some cases) impossible to properly fit the gears, to help reduce gear and valve train noise (the very reasons [among others] H -D does not use gear drives). Also why some gear drive motors are less noisy than others. It's just part of the conversation we have with our customers, who want gear drives, so that they are aware and making informed decisions.
Mike

[guest]

Thanks Mike, so if one was to have .0015 would there be much to worry about as far as using andrews 26G cams. I have heard that if runout is low then should not have to worry about fitment. thanks.

[Mike]

We do not worry until it gets past .003. The problem then becomes, how do you correct it? We cannot expect customers to buy new flywheels and pay the price to install. So we have to set an upper limit and that is .008.
Mike