Spring Rate and Oil Weight?

In the process of converting the front end of my K8 650s with a gsxr 1000 K1/2, i've managed to use the sv wheel and keep the speedo drive without modifying any of the sv parts which i'm well chuffed about, brakes are on their way as we speak, as is a well needed clip on, so will be on the road within a couple of weeks, what i will need to do after the shake down is change the spring rate (i'm assuming the gixer will run a harder spring), and also the oil weight, somone suggested 5weight oil?

who do i ask about spring rates?
are these "prgressive" springs actually any better or is it all in the head?
oil weight?

I'm about 13.5 stone and 5'10" tall, the bike is being set up for mainly road use.

any help please??

Ask K-tech, they are the suspension people, it might take some explaining to them what you've done... Hope that helps. Sorry I cant be more help.

[yorkie_chris]

Stock pointy .712kg/mm
Stock GSXR1000K2 .876 kg/mm

For 85kg rider use about 0.8kg/mm, maybe a little more for shorter forks, so I'd say the stock GSXR ones won't be too far off especially if you fit a slightly taller shock.

I wouldn't want progressive springs in GSXR fork. Cartridge internals much more advanced, so what do you valve for? You will end up with overdamped first part of travel and underdamped last part...

Springs will be fine, use stock oil. It's probably 5wt ish. The thinner the better really as the thinner oils have higher VI. (more consistent with temperature). But there you're into realms of revalving etc. Better left to specialists so just use stock oil weight.

Oh yea, im with Chris on the no progressive spring thing!!! It would undermine the front conversion. If you know the spring you need then a single spring rate spring(s) is better!

Ok thanks for your help guys, seen as the stock gsxr spring might not be that far out i think i will just give it a go as is, i will need to change the fork seals anyway as one is weaping a little, will give them an oil change then.

Cant wait to get back out on it again, i took the bike off the road in stock form, it will be going back on with the gixer front, nitron rear and a new pair of Avon Viper sports, cant wait, should be like a new bike.