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Hello folks...took the advice of a few members here and decided to do a top end replacement just for the simple reason of the unknown.....oem pistons were known to break. After looking into it a little further i noticed some play in the actual rod. The cylinder has been plated, honed and polished with a brand new top end ready to go. Im looking at doing some bottom end service also at this point. Ive had people say "run it " but not with a new cylinder and play in the rod (very very slight up and down movement-barely detectable)...I was hoping that someone with kdx experience could tell me my best move from here....an entire crank assembly is pushing close to $500, while a rod assembly is approx $100 or so....the crank itself would have to be pressed and trued but still is considerably more friendly on the debit card. I do want quality parts..oem parts are generally more expensive but if they are better than aftermarket stuff I'd go with that. I was hoping someone could reccomend which type of assembly i should go with...Ive heard good things abt Hot Rods but would like some opinions...thanks for any input folks

Ship it to a place that rebuilds crankshafts, such as Ken O'Connor, (RB Designs maybe?), Cooksey, CrankWorks, Forward Motion, etc.

It is up to your budget / trust on whether to go with OEM Japan vs. Chinese / Taiwainese.

Unless your crank halves are damaged or unable to be used again, the crankshaft can be rebuilt. Yes, it is around $175 - $200 or so, depending on what parts and company you go with, but should last for a long time afterwards.

I had mine rebuilt 3 years ago still doing good. I used pro x, I would stick with that or oem for the rod. Ive heard alot of mixed reviews on rods other than ones made in Japan. And alot of mixed reviews on aftermarket assemblies. I would also use a good quality crank bearings and seals.you dont want to go inside that motor again for a while.

royadams wrote: I would also use a good quality crank bearings and seals.you dont want to go inside that motor again for a while.

That is good advice. Any parts that are inside the bottom end, I only use OEM.

Since you will have the cases split, it is a good time to replace the other bearings and seals that are in there. While it is more money now, you will kick yourself if you have to split the cases a year from now to replace a tranny bearing.

My old 89 motor has a Hot Rod kit. It has a lot of time on it, did it 4 years ago. I did use stock crank bearings. My 220 that had 7500 miles I just re-plated the cylinder.

The manual calls for a standard radial (up and down) clearance for the rod's big end bearing of 0.26 - 0.43mm (.0009-.0017"). The published service limit is 0.10mm (.004").

Just going by feel can be misleading. Before going to the trouble and expense of tearing the engine down and buying new parts, I would get a dial indicator and actually measure the up and down clearance. You might be pleased with what you find.

Dial indicator sets are quite inexpensive these days and are very useful if you do any kind of mechanical work.

If you can feel it it's probably more than .004....That's a human hair

Don't mean to be argumentative, but I like to make my decisions and recommendations based on actual measured amounts rather than subjective observations, which will vary with each individual. Once you have the numbers and can compare them to the published tolerances, you know exactly where you are.

Ultimately, it's the OP's time and $, to do with as he chooses.

I'd recommend measuring it too