Rear spring query.

A couple of weeks ago I posted a question about a rear shock and got a few helpful responses. Following that I sourced a shock from ZX14 but i'm holding off fitting it for now due to the spring weight......

I'm about 14.5 to 15 stone kitted up. I've followed Bibio's advice and used the racetech website to calculate ideal spring. Using an 04-05 GSX-R750 as a base, it states my ideal spring weight is 7.7 Kg - which is pretty much the stock spring on the 2nd Gen SV650. The ZX14R spring is 9.7 Kg......

Thing is, the stock spring feels rubbish - really wallowy and unsupportive...

I'm confused - is the sv650 under sprung for someone of my weight? If it is, is using the GSXR750 a suitable substitute for calculating the appropriate spring weight? Am I missing something? (quite probably)

[Biker Biggles]

If the shock fits----wear it
Id put the new one in and see how it feels.My bet is that it will feel a lot better.

Thanks bud - that's what I was considering. Guess I'm looking for someone to tell me not to and why not to.

Thanks buddy, appreciate your time.

[Biker Biggles]

I put a ZX6 B1 shock in my curvy which is sprung too hard on paper,but in the real world of my limited skills it feels just fine.It certainly knocks spots off the sh&gged out original cartspring.

[Bibio]

it's not the spring that makes the shock feel wollowy it's the dampening, the OEM shock is a budget emulsion tube type so the internals will be rubbish. the zx14 has much better valving to control the damper movement better and this is why people think its stiffer.

just wind the preload down till you get the correct bike sag then ride the bike.

the only problem you will find is that unless the frontis done as well you will end up with a seesaw effect as the week front springs and dampening cause the front to go noddy.

Roger!!! Gonna get it fitted asap. Front is already done with K tech springs for my weight and 15wt oil.

[johnnyrod]

I've got an Ohlins and I think it has as standard an either 8kg or 9kg spring (think it's 8.0) which I was told would be good for up to 15 stone of rider. It's stiffer than a gixxer's spring but then it has different leverage in the linkage as it is a different bike.