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Progressive fork sprinks

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Hi all

Are the progressive fork springs for the Commando a useful upgrade or stick to new standard springs. 

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I have just bought a set for my 99 with the Covenant kit and some extended bushes, Not dear. Will post my findings once I "sprink" into action.

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Not all progressive wound springs act progressively in the allowable movement of the forks, unless the gaps at one end are very close they will not touch hence no increase in spring rate.

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I fitted a pair a couple of years ago because the front end was harsh over uneven surfaces, now more comfortable on the rough old roads around here. Not sure what the racers think, but I'd recommend for everyday riding.

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I bought about four sets of Progressive fork springs from Canada when Walridge Motors had their end of the year sale and I have fitted them in to some of my Roadholder forks. They work very well, but the original company that made them or make them are in the USA.

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Progressive is the name of the company:

https://www.progressivesuspension.com

They are also progressively wound (closer windings at one end which is supposed to be better that absorbing the smaller bumps in the road)

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Not matter what springs you fit, the oil level must cover the damper tube cap. Strangely, from the proddy racer specs the oil volume to use was 170cc per leg, but it was never this quantity used in the manuals. 150cc is the same as the short Roadholder, but the damper tube is nearly 2'' shorter. It does not seem much, but makes a big difference in Commando fork operation. Try 170cc in your Commando forks.

However, if you still have the early damper tubes fitted from '68, with holes drilled below the conical section at the bottom, fit later damper tubes. Look at how the fork functions and you will see why you need to get rid of them. 

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A resounding yes, especially with the covenant kit and more oil , as above. You will be gliding along, only problem is, you then feel how bad the back end is.!!

There are previous threads on this subject.

 


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