88 and 89 CR 125 bottom end the same?

StevieD113 7/21/2014 4:54pm
7/21/2014 4:54pm
Mark

The '88 and '89 bottom ends are different. The gearbox on the '89 is stronger and the gears are wider. The cases are also wider to accommodate this.

If you are swapping the hole bottom end, it's not going to be a problem as the top ends are the same. But you can't swap gearbox parts between them.

I rebuilt an '88 125 earlier in the year, it looked like it had been dragged out of a river. I've never seen so much gunge and sludge inside a motor before. But a good scrub in the wash tank, then a good seeing to with a wire wheel and most of the internals (gears, selector forks etc) were re-usable. Obviously, a lot of parts (seal, bearings, clutch plates) did need replacing, but most of the "hard parts" were saved. Here's a before and after pic.

You'd be surprised what can be rescued and resurrected! But, it may be more economical to just swap it for the better condition bottom end.

The clutch case was far to gone to use so we fitted a later (pre 2000/2001 ish) clutch case. These are alloy and they don't corrode/rot like the mag ones, are available cheap on ebay and are a direct bolt on swap.


Stevie



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mark_swart 7/21/2014 5:14pm
7/21/2014 5:14pm
StevieD113 wrote:
Mark The '88 and '89 bottom ends are different. The gearbox on the '89 is stronger and the gears are wider. The cases are also wider...
Mark

The '88 and '89 bottom ends are different. The gearbox on the '89 is stronger and the gears are wider. The cases are also wider to accommodate this.

If you are swapping the hole bottom end, it's not going to be a problem as the top ends are the same. But you can't swap gearbox parts between them.

I rebuilt an '88 125 earlier in the year, it looked like it had been dragged out of a river. I've never seen so much gunge and sludge inside a motor before. But a good scrub in the wash tank, then a good seeing to with a wire wheel and most of the internals (gears, selector forks etc) were re-usable. Obviously, a lot of parts (seal, bearings, clutch plates) did need replacing, but most of the "hard parts" were saved. Here's a before and after pic.

You'd be surprised what can be rescued and resurrected! But, it may be more economical to just swap it for the better condition bottom end.

The clutch case was far to gone to use so we fitted a later (pre 2000/2001 ish) clutch case. These are alloy and they don't corrode/rot like the mag ones, are available cheap on ebay and are a direct bolt on swap.


Stevie



Thanks Stevie -- your "before" pics look almost like what I'm working with. In the end, the money is about the same, if not a little cheaper for the complete bottom end. And the crank in my 88 is so rusted/seized that I have serious doubts if it can even be salvaged, which means I might have to hunt another one on ebay as well.

Correct -- I intend to put the 89 bottom end as a complete unit into my 88, along with my 88 cylinder. Thanks for the info!

So it appears now that my only real challenge is hiding the credit card statement from my wife next month : ) !

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