Suspension rebuild time

[Speeddog]

If I had looked at this thread before I left the shop... I'd have some useful measurements.
Tomorrow...

I imagine the SS is not going to have too much variation in the linkage ratio.

I don't know what the variation is on a hoop-style rear, but I've taken good measurements on the late-model ST-style stuff.

ST-style varies from about 3:1 to 2:1.
Progression is pretty quick near full extension, it's down to 2.3 or so at half-travel.

I can see how a MotoGP bike may require something quite different.
Not sure how the bumps are on their tracks either.
Any track that hosts F1 or other high-downforce or heavy cars is going to get peculiar bumps, much like natural-terrain motocross gets.

[Low594]

The comparison research that i've done was just a mental collection of rider weight and spring on the same series SS, cause anything else couldn't be reliably counted on as a comparison.

Finding someone to do a rebuild on it really isnt the issue at this point.  I actually had it all lined up.  The issue is the funds to do it.  I was laid off a few months ago and housing/gas prices here are very high.  That and having my truck broken into (stereo destroyed, CB Radio stolen and window broken) has made funds even tighter!  If i had my way it would be dialed in exactly for me, but at this time seals will have to do.  But if i can find the proper or even just better rate springs, that will have to do.

Currently the left fork seal weeps and the rear shock has only lost the droop, compression is still intact.  I'm going to contact DUCVET and see what he can do tho, thanks everyone!

[Low594]

Does anyone know if the rear springs were the same for '90s SuperSport and '90s Monsters?

[Ddan]

Different

[ducpainter]

I _think_ they still refer to "linkage ratios" even when the shock is directly connected to the swingarm and frame like an SS - it's the ratio of distance moved vertically by the axle compared to distance the spring compresses, and it's rarely 1:1 except maybe for old school twin shock machines with vertically mounted shocks - even angling the shock forward changes that ratio.

It gets more complicated pretty quickly too - the old monsters with the 851 derived suspension have a "rising rate linkage", which means the linkage ratio changes throughout the suspensions travel, getting "harder" as the suspension compresses, so your "optimal" spring rate depends on your static loaded sag... I'm not sure how close to linear rates the new non-hoop suspenson Monsters are, but by eye I'd guess _reasonably_ close, as for the SS suspension, I've got no idea...

(Interesting note, although rising rate linkages were cutting edge world superbike winning technology back in the 851/888 heyday, these days MotoGP bikes use falling rate linkages - the theory being you need much more "suppleness" in the suspension when leaned over at 55 degrees or more and the vertical movement of the rear wheel becomes a much larger movement in the suspension travel direction.)

big

I _think_....

I even understood what you said.