Putting a GSXR 1000 shock on an SV 650

/ davemosstuning Steve Driscoll poses the question on a surrogate shock transfer from a GSXR 1000 to an SV 650. If the surrogate shock is 5mm shorter, what should be done to correct the chassis?

[@catalystreactionsbw]

@Medic1911 it is 5mm shorter if I remember correctly. If you lower the front 5mm, job done. It would be an issue if sag is not correctly set and the shock hydraulics set too as the balance of the bike would be on the rear wheel so there would be a lot of weight transfer forwards when you brake hard even on the street. Dave Moss Host

[@IvoBELGIUM]

Hi Dave, Gsxr K3 shock(9mm too short) on a K4 here, i got the option to rebuild the shock to the correct size or i could drop my forks 7mm , is the result the same and what is the best option?

Actually the suspension link ratio is 1.98 in older model and 1.87 in the newer model. Therefore 5mm difference in shock length equals 10 or 9mm in rear wheel position.

[@Medic1911]

If you dont plan on racing with the bike is this an issue? I got a GSXR1000 shock that was said to be longer, but turned out to be shorter as you mentioned. I put sonic springs in the front suspension and over all it's much stiffer and nicer to ride. Are the negatives of the shorter rear shock a safety issue?

[@buzzman3200]

Couldn't you install longer suspension dog bone links to return the ride height to normal?

[@catalystreactionsbw]

There are lots of ways to get the same result and yes, that is one approach.

[@skycaptain224]

What Shock would be a better choice?

[@catalystreactionsbw]

There are so many surrogate shocks that fit an SV, you have to make sure that they are the same length minimum of 6-10mm longer for better swing arm angle and edge grip. SV650.com and other forums have excellent technical sections with lists of shock for you to consider: www.svrider.com/threads/sv-rear-shock-compatibility-chart.149360/

[@skycaptain224]

@@catalystreactionsbw Thank you Dave!

[@ThatBikerDad]

why would you have to lower the front surely just changing the dog bones would be easier especially as you'll have the shock out and linkage is at hand at the same.

[@catalystreactionsbw]

If you change the rear of the bike, you should make sure that the front is correctly set so that you have a flat/unbiased motorcycle to start with. From there, you define your own geometry.

[@ThatBikerDad]

i agree but is it not better to try and keep ground clearance to stock as much as possible?

[@catalystreactionsbw]

Ground clearance will be changed by raising (easier to flick side to side) or lowering the position of the engine (more stable in fast tracks). That is why Aprilia offers that adjustment. All track and race bikes should have engine height set by testing to determine where the rider wants it.

[@pwillikers]

Because of the mechanical advantage of the rear suspension linkage, if the shock is made 5mm shorter, the rear of the bike will be lowered appx. (3.5 times the change in the shock length) 18mm.

[@josephgbocchino]

5mm is .19 inches, that's point 19, is that going to make that much impact? just sayin...

[@catalystreactionsbw]

With the mathematics required in the swing arm as well as overall chassis geometry, 3mm will make a difference with the shock. 3mm with the forks also makes a profound difference.