Fitting RSVR shock to SV650 K5

[DavieSV]

Just to push the boundries, I've decided to try to fit an Aprillia RSVR 05 rear shock to my SV650 K5.

Q. Why?
A. Every one's fitting GSXR/ZX10 rear shocks, but can anyting else be fitted? even if it costs a little more or requires a little more work.

Q. Will it fit?
A. NO. It's too short, it has a rose joint on the bottom instead of a clevis and the spring rate is too high (unless you weigh 26 stone).

I've looked on RSV forums, and as far as I can tell, nobody can tell the difference between an Ohlins or a Sachs on the road, so I thought I'd give it a try.

Bought off Ebay for £37, the Sachs rear shock comes with adjustable compression damping, adjustable rebound damping and adjustable ride hieght.



The gas resivoir seems to be a little bit lower then the GSXR or the ZX10 shocks, so with a bit of luck I will not have to modify the battery box.

As the shock has adjustable ride hight, I thought I could unscrew the lower rose joint and manufacture a clevis to fit that would increase the shock length to the same as the original, be a perfect fit for the lower fitment and retain the ride hight adjustability.

the first thing to do was to remove the spring.



I've looked for the spring rate on the internet with no results, but measuring the the spring, I estimate the spring rate to be 580lb/in

I think I need a spring rate of 470lb/in (8.4kg/mm) approx.
The spring appears to be the same dimensions as the Ohilns(57mm ID x 160mm long), so the search is on.

I then had to remove the lower rose joint.
The rose joint has a spring loaded pin protuding through the side of the thread, so once screwed in, it can not come out
There is no provision to depress the pin before unscrewing the rose joint, so I bit the bullet and got a bigger spanner.
The result was, the rod end came out but took all the threads with it



From a quick look at the threads, I think the original thread was M18 x 1.0, so now it's stripped, I will hopefully be able to re-tap it 3/4"unf and make a clevis to suit the bottom mounting and the linkage.

Originally Posted by DavieSV

Q. Will it fit?
A. NO. It's too short, it has a rose joint on the bottom instead of a clevis and the spring rate is too high (unless you weigh 26 stone).

Not quite me and the misses two up

where can i get one

[yorkie_chris]

Ok but how do you know valving will be right for lighter spring?

[DavieSV]

That I don't know, or didn't think about!

I thought the valves were a flow/time thing,

Is there much difference on a shock with a heavy spring?

[yorkie_chris]

It's not flow-time thing, valving gives a characteristic damping force dependant on velocity of movement

Shock will have too much rebound if you put lighter spring on it. BUT that is where most factory shocks are too weak, so maybe it will be fine.

[DavieSV]

So do you think with a softer spring, rebound will be out of the adjustement range?

Is that what a revalve will do, move the adjustment range softer/harder?

[yorkie_chris]

(pics credit madmille)

[IMG]file:///C:/DOCUME%7E1/chris/LOCALS%7E1/Temp/moz-screenshot.jpg[/IMG]

This is shock piston and seal head from mille (03).
Not too good detail but you can see either side of piston is shims, down the middle is low-speed bleed adjuster ("rebound")



This is arrangement of shims.

Revalving you simply exchange these shims for thinner/thicker change diameter etc. You can also put in rings around which are thicker than centre to preload the stack and make digressive valve.

The black art, and the reason suspension shops stay in business is they know what works!

I would fit it with new clevis and see how it handles, if you get to end of clicker range then think about tearing it down to revalve.

[yorkie_chris]

http://www.shock-shop.com/Penske/Adj...h%20Manual.pdf

Go forth and geekify

[DavieSV]

Fully geeked up

so all is not lost.

Spring rate can be changed at a cost, and the piston re-shimed
Then I could have a rear shock with the perfect setup

Ringing K-tech tomorrow.

It would cost a lot more than a straight swap for a GSXR/ZX10 but could be on par with an Ohlins for less money

Stripped the original shock out tonight and placed the new shock in position. The larger diameter spring still clears everything. The gas cannister clears the battery box by a country mile and just clears the tool box by about 1mm.

I cut the tool box out anyway because I'm a tart and you could not see the shock in all it's glory.

Tomorrow I'll make a bottom clevis and shims for the top rose joint, then hopefully fit it tomorrow night to see if it works.

[DavieSV]

Just phoned K-Tech.

His answer was "It'll be right, just fit it"

He said it is a 90-95 kN spring, The Ohlins for the sv comes with a 85 kN spring so it may be a bit choppy

As for revalving if I resprung it, the valving should be OK as it is,

So non-conclusive there either