Fork spring length?

[nokturnal]

I bought some new fork springs for some 91 1100 forks, but have decided to use the 90 750 forks. 

 

Does anyone know if these springs are the same length?

 

TIA

[dupersunc]

Not sure, but there is a spacer tube under the spring, so you can adjust the length of the tube to suit.  Keep the free length of the spring and tube together, the same as stock.

[jonny1bump]

I would imagine spring rate is different been a heavier bike.

[nokturnal]

Its going to be an 1100 engine in there so not worried about the weight much. 

 

Thanks for the replies gents.

[Oilyspanner]

According to the Race Tech site the spring length and diameter are the same. 1100 engines always need slightly firmer springs, the engine doesn't weigh too much more, but combined with greater weight transfer on the over-run and acceleration, weight transfer is greater - but everyone rides differently and has different expectations.

[dupersunc]

Careful of using the Racetech site, they use American market as a reference, and 1100 used rwu forks in the US when Europe models were on usd.

 

[Oilyspanner]

Good point, the US and A 1990 750/1100 models kept to rwu  forks, unlike  every other market - cost advantage ?  I have spotted a few spring rates that were a bit off, but most are right I think, it's useful though.

[nokturnal]

My 90 forks are canadian, so USD, the 1100 forks are from a US bike, also USD. 

I have looked at the fiche and the 750 forks (US 91) are markedly different internally from the 91 1100 forks. I know it's just a drawing, but they look a lot different than the 750, and keep looking the same, old school damper rod style (almost) further into the 90s. 

[nokturnal]

According to race tech, it is the same spring for the 91-92 750 and the 91-93 1100.

 

Interesting given the forks look way different internally, and are even a different brand (Showa 750, KYB 1100)

[Oilyspanner]

Both those bikes mentioned have cartridge forks - Suzuki were the first to fit cartridge forks on a mainstream bike with the 1988 GSXR750J and the first with usd forks in 1990 (750/1100L) - Suzuki were advanced thinking ! The Slabbies had damper rod forks . The Showa 750 usd forks were a nicer fork than the1100's  Kayaba, but the 1100 forks were impressively strong and can take loads of abuse.

[banoffee]

Forks can be odd things. For example, my GK76a forks use the same seals and bushes as USD GSXR1100.

[Jaydee]

1 hour ago, banoffee said:

Forks can be odd things. For example, my GK76a forks use the same seals and bushes as USD GSXR1100.

The part numbers might be varied,  but if a Suzuki has 43mm stantions, it's the same type fork seal and dust seal across the board no matter what year or model. I've used gsxr K series, busa, TL seals in my gsxr 1100 oil cooled and water cooled 43mm forks. Even used a set of gsxr 1100K seals (were on the shelf) in K3/4 radial forks I was rebuilding. It's easier to find GENUINE Suzuki seals for newer models than older.

Same story with 41mm size stantions, one size fits all. 

Only problem is when buying full rebuild kits as bushings can be specific to whatever model it's for.

 

[nokturnal]

good info

[Gammaboy]

On 10/31/2018 at 9:26 PM, Jaydee said:

The part numbers might be varied,  but if a Suzuki has 43mm stantions, it's the same type fork seal and dust seal across the board no matter what year or model. I've used gsxr K series, busa, TL seals in my gsxr 1100 oil cooled and water cooled 43mm forks. Even used a set of gsxr 1100K seals (were on the shelf) in K3/4 radial forks I was rebuilding. It's easier to find GENUINE Suzuki seals for newer models than older.

Only place you run into issues is with fucking Marzocchi forks, they use a completely different style of dust wiper to the Jap forks, and a slightly different diameter on the OD of the oil seal...

46mm Paiolis RWU and USD run the same seal pack as 46mm ZX9/SV1000 and all the 46mm dirt bike forks (except, of course, Marzocchi).