Advice on front fork springs

[pedro3178]

So after lots of reading it seems this is one of the top things to do to the SV . I wondered if these are any good or simply cheap/nasty and if so what would be recommended please

https://www.ebay.co.uk/itm/Hyperpro-...YAAOSw6rRc59Y3

[Bibio]

dont get progressive springs get linear.


you also need springs for your weight so the preload is correct.

[pedro3178]

Originally Posted by Bibio

dont get progressive springs get linear.


you also need springs for your weight so the preload is correct.

Thanks.

Came across this .... https://www.ebay.co.uk/itm/Suzuki-SV...QAAOSw24RbINP1

It doesn’t state 650S but if I am correct , the 1999-2002 S and non S used the same front springs ?

[Biker Biggles]

Yes, the S and N forks are the same. What you need to work out is the spring rate that you want for your weight and style. I think the standard springs are set up for a ten stone ish rider. Some of us are a bit(lot) heavier than that.

[pedro3178]

Originally Posted by Biker Biggles

Yes, the S and N forks are the same. What you need to work out is the spring rate that you want for your weight and style. I think the standard springs are set up for a ten stone ish rider. Some of us are a bit(lot) heavier than that.

Thanks. I’m a slim guy but would still be 2 stone heavier then if they are set at around 10. It’s the forks pushing into the ground I notice on Hardish breaking. I’ve heard this will solve that but also offer better handling .

[Bibio]

so your 12st?

spring rate depends a bit on your riding style as well as your weight then add a splash of fork oil weight and things can get a bit complicated.

the curvy have a heavy spring rate on the rear shock so you can get away with going a bit heavier on the front. this is the main reason for the pogo effect when riding as the front is constantly nodding.

this all depends on static/rider ride height. best setting that up first.

my advice for what its worth:
take forks apart and weld the rebound holes up on the damper rods and dress the welds.
get yourself some .85 springs. from the link you posted.

get yourself some Silkolene RSF 10w or 7.5w. idealy you need to mix the oil weight to achieve the correct rebound.

set oil height to 100mm.

under no circumstances set your bike up for "race" that most websites advise. your not riding on a race track your riding on a road.. its a completely different ball game when it comes to suspension.

[Dave20046]

As a brand Hyperpro are fine. Or look at racetech. Use the racetech calculator for the spring rate.

https://www.racetech.com/ProductSear...650S/1999-2002

(click spring rate calculation).
+1 to what bibio says

Progressive springs are a different product from linear, linear are probably the one you want.

Edit: if you're not big on welding you can get emulator kits (£). Bibio - am I right in saying they're the equivalent to what you're suggesting?

I'd also strongly consider replacing the seals while you're in there.

[pedro3178]

Was enjoying reading until you said weld! never done any welding unfortunately, is that part a must? Maybe have to find someone if that’s the case

[glang]

I've always wondered if the rebound holes couldn't be tapped so a plug can be screwed in and securely peined in place rather than welding....

[Adam Ef]

Originally Posted by pedro3178

Was enjoying reading until you said weld! never done any welding unfortunately, is that part a must? Maybe have to find someone if that’s the case

There will be someone near you who can do a couple of small spot welds easily and then you can sand them back and clean them up.


Emulators will have no effect if the oil is bypassing them via unwelded holes.


K-tech fork springs are good. Listen to Bibio and search the threads on here for info. I did this a year or so ago and ended up getting my SV very well set up... and then sold it