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Fork springs, compression ratio some advice pls.

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Old 10-07-2009, 10:02 AM
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Fork springs, compression ratio some advice pls.

Howdy.

So i'm about to order some forks springs. I will run stock 5wt oil. as a base.

Option 1: Racetech
Based on the rider without gear, for my bike, RaceTech calculated:

FRONT FORK SPRINGS
Recommended Fork Spring Rate for Street: 0.895 kg/mm (use closest available)
Stock Fork Spring Rate: .585 kg/mm (stock)

the next best rate i will select would be a .90


Option 2: Sonic Springs
Based on the rider with gear (210 lb or so), specified bike weight 475lbs wet, Sonic calculated:

Calculated Spring Rate: 1kg/mm
For Rider Weight = 210 lbs.
Bike Weight = 475 lbs.
Bike Type = Sport Bike
Riding Style = Aggressive Street
Tank Bag = No


thnx in advance.
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Old 10-07-2009, 11:28 AM
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Originally Posted by Karbon
Howdy.

So i'm about to order some forks springs. I will run stock 5wt oil. as a base.

Option 1: Racetech
Based on the rider without gear, for my bike, RaceTech calculated:

FRONT FORK SPRINGS
Recommended Fork Spring Rate for Street: 0.895 kg/mm (use closest available)
Stock Fork Spring Rate: .585 kg/mm (stock)

the next best rate i will select would be a .90


Option 2: Sonic Springs
Based on the rider with gear (210 lb or so), specified bike weight 475lbs wet, Sonic calculated:

Calculated Spring Rate: 1kg/mm
For Rider Weight = 210 lbs.
Bike Weight = 475 lbs.
Bike Type = Sport Bike
Riding Style = Aggressive Street
Tank Bag = No


thnx in advance.

and your question is???? You should also check into revalving the forks also.
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Old 10-07-2009, 11:54 AM
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Not sure how fast your ride nor the kind of roads, but for street use I have a preference for progressive springs. I bought the hyperpro kit, comes with oil and recommended settings and I have been very happy about it.
Now my track bike is a different story, 0.9 springs, revalve job, Maxima oil etc.
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Old 10-07-2009, 02:13 PM
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yeah valving is the next step. One thing at a time i suppose. I generally ride spirited twisty roads.

I was just wondering whos numbers i should go by. Racetech or Sonic.
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Old 10-07-2009, 02:26 PM
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i went by the sonic #'s. .90's - i'm around 180lbs.

when i had the stock valves i used 7w oil & 145mm air gap. no needle grind & no hole drilled.

it'll do you fine until you get it valved

tim
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Old 10-07-2009, 04:00 PM
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cool.

i read on another forum racetechs numbers are somewhat off. I referenced the chart on traxxion's website and found the sonics were closer as well.
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Old 10-07-2009, 04:10 PM
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Originally Posted by Karbon
cool.

i read on another forum racetechs numbers are somewhat off. I referenced the chart on traxxion's website and found the sonics were closer as well.
That would probably be a very subjective call... Off, based on what?

Closer in this case being your weight vs the labeled spring weight, yes...

But the labeled spring weight vs the effect on the suspension might not be the best at the labeled weight...

If you click "race" on Racetech you get .982 Kg/mm which is about what Sonic suggested... And that's probably a better equivalens to "aggressive street" than their "street" which is more comfort oriented...
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Old 10-07-2009, 04:29 PM
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When Greg sets up front ends he wants to know about the prevailing road conditions, your weight w/FULL GEAR, how aggressive you are in style and how good you are as a rider.

Yeah, heh, I know but it really helps him dial it in. Then he helped me set it up. If I read the temperatures right and adjust my tires accordingly, even with a run-out set of Powers the kid is hangin' off and I'm close behind.

He did do the valves too while he was in there but it included polishing, etc, etc. You'll have to pm him about that. Some kinda suspension guru stuff.

Certainly works .
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Old 10-07-2009, 07:04 PM
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cool. thnx for the info dudes.
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