Wrist Pin Clearance

[gregoryp]

I have an 81' that I have apart right now. Have some new pistons and wrist pins. The manual says the pins should be a snug fit in the small end of the rod. My pins, new and old measure 0.787" and the bore on the small end of the rod measures 0.790, so I have about 0.003" difference. Do I need to replace the rods?
Thanks,
Greg

 

[xjwmx]

If I remember, the factory manual says there shouldn't be any detectable wiggle and and if you feel wiggle then replace the rod, pin, or piston as required to eliminate it. I think it also says the parts should have oil on them when you test them.

 

[gregoryp]

Without oil I can definately wiggle it some. I really didn't want to tear into the bottom end. If I do that, then do I rephase??? I'll check it with some oil and see how it feels.
Thanks,
Greg

 

[xjwmx]

Just to make sure I told you right, go to biker.net and download a manual for yourself if you don't have one.

 

[gregoryp]

I have a manual and I looked at the one that is available on here and they both say the same thing, to just feel if it wiggles with oil. It does, so It looks like I'm going to be replacing rods. When you look in the bores of the rods the top and bottom where the load is is silver and the front and back are brown, so it definately looks like there is some wear. I also checked my clearance on the thrust bearings between the side of the rod and crank and I'm at 0.021" on one side and 0.023" on the other. the book says the range is 0.006" to 0.016".

 

[xjwmx]

I've read on here of people spending a surprising amount of money to fix the engine internals. The cheapest route might be to look on ebay for parts from a seller who'll let you return them if they're out of spec. Maybe look for a crank with rods and pistons. That's how I'd start, anyway.

 

[XSLeo]

I rebuilt a crank with all new bearings and rods and spent around $500 for the parts.

 

[jamesgs4]

That 500 cost is what keeps me from doing it, maybe someday ill take the plunge.