Date: 19-04-24  Time: 01:10 am

Author Topic: Fitting new fork springs  (Read 939 times)

vinnyb

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Fitting new fork springs
« on: 22 July 2017, 02:07:33 pm »
 My new fork springs arrived today. The forks had new oil a few weeks ago so I don't need to change that. I was wondering if it's possible to lower the bike onto the fully compressed forks to measure the air gap while on the centre stand or will it just tip forward too far and roll off the stand? It would be nice if I can avoid having to remove the forks if possible. I have a trolley jack so I can lower it gradually and cable ties for the brake lever if needed.

vinnyb

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Re: Fitting new fork springs
« Reply #1 on: 22 July 2017, 04:56:07 pm »
Just done it no probs :)

tommyardin

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Re: Fitting new fork springs
« Reply #2 on: 22 July 2017, 05:56:32 pm »
Well done, not sure how you did it but it would seem risky allowing the weight of the bike to push the fork legs into their uppermost
(Compressed, stanchion top plug/bolts out) position while on centre stand.
I think I would prop the bike up at the front by chocking under the down pipes with blocks of timber, removing the front wheel and then sorting each leg individually by pushing up the leg and then chocking it in that position while checking the oil level. Ideally the legs should really be upright when checking the oil level not at the rake angle of the forks, but may just be splitting hairs.


Its been a while since I did my forks, well not that long, but seeing I am getting on a bit my old memory does not serve me so well, If I recall the oil level/air gap is measured before the springs go into the stanchions.
I had to reduce my oil level because I fitted cartridge emulators when I converted my forks and fitted linear springs, the YSS emus displaced about 20ml of fork oil, but the Linear Ohlin springs were very slightly less tightly wound (Constant pitch as opposed to dual pitch) than the original Yamaha springs so my guess was that one cancelled the other out, so I put the 20ml back in each leg while doing the fine tuning to level and viscosity.


Let us know how you find the ride when you have finished final adjustments and tuning.
Oh! What springs did you decide on? Some swear by Linear springs that suit your rider weight others say Progressives are best, but I'm sure what-ever route you go it will be  vast improvement on the wrist breakers that Yamaha fit as standard.


I personally think that there is one spring weight suits all.
I feel that a lady rider weighing about 8.5 stones needs a much lighter spring that a beefy male rider weighing in at 18 stones, but again it is an opinion and lots will disagree, after all if you fit a customised rear shock the custom builder wants to know your rider weight fully togged up ready to ride so he can fit the right spring, Nitron certainly do.         
« Last Edit: 22 July 2017, 06:11:20 pm by tommyardin »

vinnyb

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Re: Fitting new fork springs
« Reply #3 on: 22 July 2017, 06:24:58 pm »
Hi Tommy, I was a bit nervous when I did it, I must admit. I jacked the downpipes 'til the rear wheel was touching the floor and slipped 3 12mm thick plywood boards under the front wheel to stop it tipping to far forward, took the caps off and gradually lowered the jack and it dropped forward with no dramas at all. I ended up buying Hagon springs which to came with 10w oil, I was expecting 15w but that's obviously what they recommend. I was torn between linear and progressives but went with the Hagons in the end. Waiting for the new shock now.