How can I stiffen up my forks ???

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john21z
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How can I stiffen up my forks ???

Post by john21z » Sun Mar 04, 2012 7:50 pm

Hi can anyone offer any advice ?.My forks are very soft.They bottom out under heavy breaking and they have only
just been serviced .Apart from buying new springs is there any way to stiffen them up ? . For example bigger spaces
or would this have adversed effect? . :grin:

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jetblack
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Re: How can I stiffen up my forks ???

Post by jetblack » Sun Mar 04, 2012 7:57 pm

Stiffer springs.

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mo haggs
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Re: How can I stiffen up my forks ???

Post by mo haggs » Sun Mar 04, 2012 8:30 pm

or try a heavier fork oil
vic-vtrvfr wrote:they're like rocking horse poo with sprinkles of unicorn horn on top.

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Re: How can I stiffen up my forks ???

Post by banoffee » Sun Mar 04, 2012 9:59 pm

Rick Oliver fork kit
attention 2 detail - bike valeting and more

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Re: How can I stiffen up my forks ???

Post by magg » Mon Mar 05, 2012 3:10 am

What was doe during the service?

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lukemillar
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Re: How can I stiffen up my forks ???

Post by lukemillar » Mon Mar 05, 2012 4:56 am

john21z wrote:Hi can anyone offer any advice ?.My forks are very soft.They bottom out under heavy breaking and they have only
just been serviced .Apart from buying new springs is there any way to stiffen them up ? . For example bigger spaces
or would this have adversed effect? . :grin:
bigger spacers won't stiffen them up - you'll need a different spring rate for that.

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Re: How can I stiffen up my forks ???

Post by 999Gomerz » Mon Mar 05, 2012 8:31 am

lukemillar wrote:
john21z wrote:Hi can anyone offer any advice ?.My forks are very soft.They bottom out under heavy breaking and they have only
just been serviced .Apart from buying new springs is there any way to stiffen them up ? . For example bigger spaces
or would this have adversed effect? . :grin:
bigger spacers won't stiffen them up - you'll need a different spring rate for that.
Bigger spaces will stiffen them up, as this increases preload on the fork spring.

But, what springs are in it at the moment?

And does it bottom on the road or the track?

Is it fine everywhere else? If it is add some oil, start with 10mm.

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Re: How can I stiffen up my forks ???

Post by lukemillar » Mon Mar 05, 2012 8:40 am

999Gomerz wrote:Bigger spaces will stiffen them up, as this increases preload on the fork spring.
That doesn't stiffen them up. It just moves the amount of load require before the spring will start to compress. It will still compress at the same rate as before as preload doesn't affect spring rate!

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Re: How can I stiffen up my forks ???

Post by 999Gomerz » Mon Mar 05, 2012 8:55 am

lukemillar wrote:
999Gomerz wrote:Bigger spaces will stiffen them up, as this increases preload on the fork spring.
That doesn't stiffen them up. It just moves the amount of load require before the spring will start to compress. It will still compress at the same rate as before as preload doesn't affect spring rate!
Think about what increasing the required starting force does to the force required to compress the fork fully?
It will increase the force required to fully compress the fork thus making the bike ride higher in the stroke for a given force. ie get you off the bottom.

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Re: How can I stiffen up my forks ???

Post by magg » Mon Mar 05, 2012 9:05 am

Increased preload will increase static ride height and has no effect on spring rate. The fork will move the same distance for the same load.

Should we not start by measuring the unloaded and loaded sag to establish whether the current spring rate is correct. Then having selected the correct springs adjust the oil level to achieve the appropriate dive under breaking and finally adjust the compression and rebound damping to match the spring rate.

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