86 RM250 shock into 84 RM500 ?

[Dono113]

Gotta rebuild my old shock and it's in pretty bad shape, found a good condition RM250 86 model shock that looks the part, good clicker etc. would just have to change out res. line as it's a shorter lenght, anyone tried this or done this??

[D project]

Don't see why not,as long as they are the same length

[BAHNZY]

The challenges;
1st is getting the shock in with the correct eye to eye length.
2nd is making sure that you have enough piston travel to match the suspension stroke.
3rd is getting the valving correct
And 4th is getting the correct spring.

Why?
Because the 86 model (if I'm correct) is a rising rate linkage system whereas the 84/85 is is not. I fitted a KTM Ohlins shock into my 84 125 and whilst it was 1/2 reasonable on the small hits, the big hits the suspension was way to harsh and kicked like a mule. Valving and a linear rate spring rather than a rising rate spring got it right, but not after a lot of work.

[Dono113]

Knew there where reason why I hadn't read about it, thanks brother I would spend the right money money fixing my shock than wasting money on pipe dreams so to speak.

[JohnnyO]

Bahnzy is right, the 2 rear suspension systems are chalk and cheese. They will be different in spring rate, valving and shaft travel. Not worth the headache...

[Dono113]

Would any one have a good spare shock laying around???