Changing a fork seal

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masterofinsanity
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Changing a fork seal

Post by masterofinsanity »

Let me tell you now this aint no 5 minute job.And you don't need any special tools for this job but i'm sure it'd make it a damn sight easier! bear in mind this was done with no special tools, please read the manual and also Diesels fork rebuild in the workshop on the main site.

first things first lets get the basics out of the way ie: you are going to remove the forks and replace the seal, therefore you are going to need to lift the front of the bike up in the air.How you do this is your choice but i have used a under the yokes paddock stand which must be used in conjuction with a rear stand for security.Now... if you've not used one of these before then you wont know you have to remove the fairings otherwise you WILL crack the nosecone! So bike on rear stand, take the fairings off and lift the front up.Bear in mind you will no doubt come across rusty seized bolts which are usually cap heads (allen key type) and will round off when you try and undo them.

So fairings off and bike on the paddock stand.

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next job is to remove the front wheel.So first unbolt the calipers (otherwise the wheel won't come off), if you are only changing one seal then remove the caliper on the side that needs changing.Undo the 2 pinch bolts on the bottom of the right hand side fork leg, then undo the front wheel spindle bush from the RHS and remove, then undo the 2 pinch bolts on the LHS which will enable you to push/pull the front wheel spindle out and remove the front wheel.

front wheel spindle.
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front wheel removed
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if you haven't already done so remove the front mudguard.
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tip: its a good time now to slacken off the top of the fork leg whilst its still in the yokes (pair of plumbers wrenches does the trick)

you will then need to undo the pinch bolts that hold the fork leg in, 1 on the top yoke, 1 on the clipon, and 2 on the bottom yoke, then slide the fork leg out.
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now its time to disassemble the fork leg, unscrew the top of the fork keeping it upright otherwise the oil will flow.make sure you have a suitable container ready to catch the oil.empty the oil out of the fork then turn upside down and remove the bolt (watch out for the gasket washer) from the bottom of the fork leg.you will then be able to remove the internals from the fork leg.

Image

next you will need to prise the dust seal from the fork leg, use a suitable tool, flat blade screwdriver etc and remove the dust seal, then the retaining clip, then holding the bottom of the fork leg and the outer sleeve give a hard pull to split the two.

Image

you will then need to remove the outer bush, inner bush, washer and oil seal.it is good practise to place a thin plastic bag over the end of the fork leg before refitting new seals and bushes.

refiiting is obviously a reversal of removal, bear in mind......take care when refitting the outer bush, slide the outer bush onto the leg, with the outer sleeve upright in a vice, drop the fork bottom with all components attached into the sleeve, and now is when you need 3 pairs of hands, get someone to hold the fork bottom half in while you GENTLY tap the outer bush into the sleeve using the washer to ensure it goes in level, i used an old phillips screwdriver which i ground to a flat to tap the washer so as not to damage the washer or fork stancion....this takes a lot of practise and patience (and swearing) you could of course opt for the special kawasaki tool. once the outer bush is seated properly, fit the oil seal, make note when removing which way the seal fits in.then the retaining clip followed by the dust seal.

Turn the fork upright again and reinstall the internals, screwing the top of the fork leg back into the sleeve.NOW is the tricky bit you have to compress the spring completely to reinstall the bolt (including gasket washer) that you removed from the bottom of the fork leg that means you get your fattest friend to lean on the fork whilst you screw the bolt back in...how did i do it? i had the fork upright with the mudguard brackets resting on a pile of bricks then whilst using a fence post as a lever to compress the fork i screwed the bolt back in from underneath, tricky, dangerous and mental! Obviously if you have the special fork spring compression tool its no problem.

then all you need to do is unscrew the top of the fork and fill with the appropriate amount of new fork oil.Then reassemble the bike
JOB DONE!
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Re: Changing a fork seal

Post by zimm »

sounds fun.. got mine to do this week.. might wimp out and pay someone.

H forks the same Baz ?
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masterofinsanity
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Re: Changing a fork seal

Post by masterofinsanity »

just had a quick look in the manuals the internals are different and different methods of disassembling but its all in the manual.
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Re: Changing a fork seal

Post by MillaMeter »

That's exactly how I did mine back in Feb, was so much fun :smt003
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Re: Changing a fork seal

Post by Jeppo »

Just had a fork seal blow, is it worth changing them both incase the other one may well be on its way out or not worth it?
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Re: Changing a fork seal

Post by MillaMeter »

Jeppo wrote:Just had a fork seal blow, is it worth changing them both incase the other one may well be on its way out or not worth it?
Hi,

While you got 1 out, you might aswell change the other as you'll only find it'll blow quite soon after you replaced 1 side then you'll have to do a whole front end strip down again :(

Only 1 of my seals blew last year (right side) as I had the right fork in bits I thought while I'm at it I might aswell change the other.

There's nothing more frustrating then having to take the bike apart again after fixing 1 side to fix the other!

Regards

Rich
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Re: Changing a fork seal

Post by wonderpupp »

My local mechanic has kindly allowed me the use of his special for tools to do mine,when I get round to it.

But he wants nothing to do with doing it, cos he hates doing fork legs and would rather lose out on the labour cost for the joy of laughing at me trying to do it on a saturday morning wth a hangover.

I like my mechanic. He teaches me everything I need to know so costs me nothing, and said he appreciates having an attractive young lady in his workshop all covered in grease and oil an saturdays. :smt005
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Re: Changing a fork seal

Post by Lozinsx »

Not zxr forks, but the principles the same and this link may help and has a couple of good tips in it..
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Re: Changing a fork seal

Post by UK II Kazawacky »

That's exactly what I'm trying to do atm, but mine doesn't come apart with a "hard pull", I reckon the copper ring you see on picture 7 has annealed itself to the chrome and it won't bloody come out!
This thread is awesome though Baz! Step-by-step guides with pictures rule :smt003

Cheers, Nick


EDIT: STICKY THREAD!!!
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Re: Changing a fork seal

Post by mikey_m »

When i finished mine last week, i never had to compress the spring to get the bolt back in the bottom. Maybe i have different forks? Its a zxr H2.

:smt017
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Re: Changing a fork seal

Post by reds »

yeah i have the h model and it is very easy to put the leg back together - dont need to compress it with a home made jig or anything (although I had already made one to do it with !)
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Re: Changing a fork seal

Post by Neosophist »

I have seen people compressing the later forks with ractchet straps and all kinds of home-made kawasaki tool to put them back together.

When I did mine I found an easier way to do it.

This might help somebody.

When you are putting the fork legs back togther, lay them horizontal (flat) and extend the damper rod fully tha the spring goes over and slide the two units together, the damper rod should be fully extended now as it drops in on itself when vertical which is why you need to compress them so much.

Either find a wall or have a friend put the bolt in and ready to turn it.

You dont need to compress the fork half as much now as the damper rod will be near the bolt anyway, so push the fork against the wall and to compress it while keeping it flat (still need to compress it a bit obv.) and have a friend tighten up the bolt, it should catch.

have them tighten it as much as possible while your compressing the fork to make sure you dont strip any thread etc.

The rest should be straight forward. I wanted to make a video but will have to wait until i change the seals again.

Oh I recommend Kawasaki genuine seals too, they last longer than the pattern parts.. and always change them in pairs :)
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Re: Changing a fork seal

Post by masterofinsanity »

This is how i compressed the fork on my TL, it might give you an idea what to use.
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Re: Changing a fork seal

Post by ajblamey »

A brilliant thread, and praise be to masterofinsanity for the help and tips. Here's one I'd like to share - I got sick of tapping the ring and washer into the alloy fork outer, and was worried about damaging my stanchion in the process, so I had a think. I cut a section of 1.5" plastic waste pipe as square as possible, split it along its length, softened it in a mug of hot water, and popped it around the stanchion. With the axle clamp hung from my shed ceiling on a bungee, and the alloy outer resting on the work bench, I lowered the stanchion, gripped by the plastic pipe, and everything popped straight in! Preparation time = 5 minutes; Seal fitting = 5 seconds.

Image,Image.

However, I am now baffled by the fork oil - where & when does it go in? The manual refers to the level when there is no spring fitted, measured from the top of the inner tube, but if you are chucking it in an empty stanchion, won't you end up standing in it?
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Re: Changing a fork seal

Post by ZYCHU »

Hello,
I'm not sure if all yours solutions to the problem are ok, because you should remove air from your new oil by moving up and down the rod.
In the picture you can see how i squeezed my spring (with new air free oil).
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