Date: 28-03-24  Time: 23:24 pm

Author Topic: Forks Leaking  (Read 1255 times)

old son

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Forks Leaking
« on: 06 May 2020, 05:26:39 pm »

I noticed today that one of the forks on my 05 Gen1 is leaking from the seal at the top of the leg. The bike has covered £32k miles. It would make sense to me to change the seals on both legs. Obviously change the oil. Is there anything else I need to change/check at the same time?


Where is the best place to buy the new parts?
What is the best grade oil to buy and how much do I need?


Thanks

Trebus

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Re: Forks Leaking
« Reply #1 on: 06 May 2020, 05:48:29 pm »
I’m doing the same thing at the moment. The bushes wear and will likely need replacing too. Oil seals, genuine NOK are recommended but if the dust seals need replacing then cheap ones should do. Bushes, Yamaha or could try aftermarket. Got mine from K Tech. Also have K Tech linear springs to go in. Mine are fully stripped down and need to find a few hours to get them back together.

Oil- K Tech recommended a 10w Motul Factory. Of course people change to their preference so not sure if a best oil can be determined. 1 litre is enough for both legs. Something like 0.44Ml per leg but needs to be measured via air gap rather than actual amount.
« Last Edit: 06 May 2020, 05:50:11 pm by Trebus »

PieEater

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Re: Forks Leaking
« Reply #2 on: 06 May 2020, 06:08:44 pm »
Definately change the bushes at the same time, what about springs if they have not been done?
I got my parts from K-Tech.
I beleive the stock oil weight is 10w, but I know folks on here have used 7.5w and potentialy lower and been happy with the results. I think this would come down to rider weight and riding style i.e. a lighter weight oil would suit a lighter rider and / or a more plush, relaxed riding style.

Edit:\ Beaten to it  :)
« Last Edit: 06 May 2020, 06:09:48 pm by PieEater »

Trebus

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Re: Forks Leaking
« Reply #3 on: 06 May 2020, 07:23:37 pm »
https://store.ktechsuspension.com/

Put in the bike details and you can see they have all the seals / bushes. Plenty of other places to get stuff but they are local ish to me and I picked up the bits before lockdown.

Pyramid do bushes a bit cheaper but there was a case recently where a forum member had some issues with fitment. Not fitted mine yet but they look to be the same size!

unfazed

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Re: Forks Leaking
« Reply #4 on: 06 May 2020, 09:08:15 pm »
Stock oil on 1000 is about 5W and 7.5w is a better all round option 10W can make the front too stiff, but might be to some peoples liking.
If doing the forks yourself, before reassembly set the rebound adjusters to about 21 clicks out from full in this is around  the centre of the adjustments available on the adjusters when dismantled which is from memory around 42. This ensures you have the full range of adjustment when they are fully assembled which I think from memory is 21 clicks total.
The nut inside in the forks to hold the damper rod when opening the bottom bolt is 26mm.I used a a 3/8drive 26mm socket duct taped to the end of an vacuum cleaner tube to hold it while undoing the bolt

PieEater

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Re: Forks Leaking
« Reply #5 on: 07 May 2020, 12:25:53 am »
Sorry yes, stock fork oil is 5w not 10w as I thought  :)

old son

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Re: Forks Leaking
« Reply #6 on: 07 May 2020, 09:38:41 am »
The nut inside in the forks to hold the damper rod when opening the bottom bolt is 26mm.I used a a 3/8drive 26mm socket duct taped to the end of an vacuum cleaner tube to hold it while undoing the bolt



I watched a couple of videos on how to do this job and don't quite understand your statement above. There is a bolt head up through the bottom of the suspension leg. Are you saying there is a nut on the other side of this? The main video I watched was from Dels Garage and his leg had a cartridge in it, maybe that was the difference? There was certainly no nut on the inside of that leg that needed to be retrieved.

unfazed

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Re: Forks Leaking
« Reply #7 on: 07 May 2020, 09:52:07 am »
Are we talking about the FZS1000 carburetor model with conventional forks as it says on you profile?
The FZ1 fuel injected model has upside down forks and is a totally different system.

PieEater

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Re: Forks Leaking
« Reply #8 on: 07 May 2020, 10:39:01 am »
The external damper rod bolt passes through the bottom of the leg and screws directly into the damper rod, there is no nut inside the fork that it screws into. I think what Unfazed is referring to is a method to stop the damper rod assembly turning whilst undoing the bottom bolt, but he will need to clarify that.

Trebus

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Re: Forks Leaking
« Reply #9 on: 07 May 2020, 12:00:28 pm »
Check out my picture. The damper assembly is resting on the glove and bolts into the fork lower. The tool is used to stop this spinning to get the bottom bolt out from underneath the fork leg lower.

I made one using a socket welded onto some tube in second picture.

old son

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Re: Forks Leaking
« Reply #10 on: 07 May 2020, 08:23:16 pm »
Many thanks, I understand now.