I am in the middle of building my '93 KX250. I replaced the main bearings, and I got a Pro series rod kit. I sent the rod kit, and the crank to a shop, to have them install the rod. This is one of those things I just cant do, because I dont have the press or the jigs to do it, although I HATE having any one else working on my stuff!
I got the new bearings in the cases, and then installed the newly rebuilt crank. Then, I figured Id spin the crank around to feel how nice the new bearings felt. BOTH ends of the crank have some SERIOUS wobble!!! Also, looking down onto the crank as it is in the case, there is a gap between each crank half, and the case half walls. These gaps also vary, as I spin the shaft. I am COMPLETELY pissed!
It assembled very nicely, I did the whole freezer/oven thing, and I had to use very little effort to assemble everything. Theres no way I did this to the crank upon installation. (the worst thing I did was use a rubber mallet to tap around the last case half as I lowered it on.) I put a call into the guy who did the crank, but as it is Sunday, no answer. Im gonna call him tommorrow and see what the hell his problem is. This kills me.
This guy was telling me when I took the crank in ( regarding balance), that it would be no problem, that he has some sort of jigs to assemble the halfs,so I wouldnt have to worry about him "knocking " on the crank with a hammer. Well,I can see jigs, or guides being able to make sure that the halfs spin on a common center, but besides that, the crank halves can also be either "pinched" or "spread", which is what I think is wrong with mine. My thinking is seriously outdated, but it used to be put a couple of run out gauges on the crank halves, and then hit them with a brass hammer to get them on a common center, and then put the gauges on the shaft ends, and adjust the thing until there was no runout. IF this guy just pressed the thing together in a jig, how is that enough?
any comments would be appreciated.
Neil
I got the new bearings in the cases, and then installed the newly rebuilt crank. Then, I figured Id spin the crank around to feel how nice the new bearings felt. BOTH ends of the crank have some SERIOUS wobble!!! Also, looking down onto the crank as it is in the case, there is a gap between each crank half, and the case half walls. These gaps also vary, as I spin the shaft. I am COMPLETELY pissed!
It assembled very nicely, I did the whole freezer/oven thing, and I had to use very little effort to assemble everything. Theres no way I did this to the crank upon installation. (the worst thing I did was use a rubber mallet to tap around the last case half as I lowered it on.) I put a call into the guy who did the crank, but as it is Sunday, no answer. Im gonna call him tommorrow and see what the hell his problem is. This kills me.
This guy was telling me when I took the crank in ( regarding balance), that it would be no problem, that he has some sort of jigs to assemble the halfs,so I wouldnt have to worry about him "knocking " on the crank with a hammer. Well,I can see jigs, or guides being able to make sure that the halfs spin on a common center, but besides that, the crank halves can also be either "pinched" or "spread", which is what I think is wrong with mine. My thinking is seriously outdated, but it used to be put a couple of run out gauges on the crank halves, and then hit them with a brass hammer to get them on a common center, and then put the gauges on the shaft ends, and adjust the thing until there was no runout. IF this guy just pressed the thing together in a jig, how is that enough?
any comments would be appreciated.
Neil
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