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Discussion Starter · #1 ·
I'm going to replace the fork seals on my '03 SV1000 and was wondering whether it would be advantageous to use a non-stock oil weight when I refill the forks. I only weigh about 150 pounds.

Thanks!
 

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I weigh #150 as well, and wouldn't go heavier than 5wt. The higher the VI the better. Check out Red Line suspension fluids. They're a bit pricey but worth it.

I would also strongly recommend a set of .85 springs.
 

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Discussion Starter · #5 ·
So the 0.85 springs would ostensibly give a softer-than-stock front-end? But the 5W oil would firm it up... Would the net result be a similar front end feel, just with more linear compression/rebound? Or am I thinking completely backwards? Sorry, I'm new to suspension setup. Thanks for the advice.
 

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Well, that's not quite how it works. Springs are specified for your weight, and valving has to work with the springs. Stock valving is a little on the light side to enable them to work with the progressive springs (remember? too light on top, too stiff on the bottom).

OK, now the next part is tough to explain. Not all oil of the same claimed weight is the same. That is to say that one manufacturers 5wt isn't the same as anothers. For example, PJ1 Fork Tuner 5wt is heavier than Bel Ray Fork Oil 7wt. The numbers to pay attention to are the cSt and VI. For the SV forks, cSt between 17 and 19 work about the best. And the higher the VI the better (the higher the VI the more heat resistant it is). Within the 17-19 cSt range the two highest VI are Bel Ray HVI 5wt (VI=345) and Red Line Light{yellow} (VI=407).

Too heavy an oil negates the comression/rebound adjustments.Too light an oil turns them into on/off valves.

The straight wound .85 springs will have a much more predictable linear feel. And with the correct oil level will provide a comfortable ride w/o excessive front end dive.

If you want a truly tuned suspension, buy a set of gold valves from Race Tech. You have a luxury that many 1K owners can't enjoy.......rebuildable cartridges. K3 was the only year that Suzuki made easily rebuildable carts on SVs. The kit from Race Tech comes with the gold valves (obviously), instructions, bags of shims, and a coded number that accesses their online DVC (Digital Valving Calculator). The DVC will give you the necessary info on building the proper shim stacks for compression and rebound according to the info that you provide. It will also specify bleeder hole size, oil level, approx. preload, and initial comp/rebnd settings.

Any of it is money/time well spent.
 

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Discussion Starter · #7 ·
Thank you for the explanation. I think I'll just do the oil and possibly the 0.85 springs as well this go-around. I'm assuming the correct oil level will be the stock level, or will that need to change with the new springs?
 

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Depends a bit on use, riding style, road surface, etc...

Generally, if you are a "sport rider", are aggressive, might/will do a trackday, then you will probably want to run 5-8mm higher level than stock (less air above the oil to compress=less dive). Much higer than that and you risk ''hydro-lock".

Be sure to re-do your setup from the beginning, meaning start with sag.

If you'd like, I can send you a copy of "Suspension 101" by Traxxion Dynamics' Max McAllister. Just PM me with an e-mail address to send it to. It will help you to sort it all out in understandable terms.
 
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