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Originally posted by Harry
Fork Seal replacement 101

Tools you will need before you start.

12mm spanner

14mm spanner

6mm allen key

Rearstand and Frontstand preferable (of the headstem variety)

10w or 15w fork oil

Replacement fork seals

Rags rags rags

2 cans of degreaser

**** Thanks have to go to Stealthassasin for loaning me his bike for the project!!! **** he tells me his bike never felt better!!


Take One CBR250RR

Remove allen bolt on front, 3 allen bolts from each side of the nose cone and remove mirrors. Pull front fairings off half way and

then disconnect front indicators

Remove bolt which holds brake lines in place

Undo two 12mm bolts which hold instrument cluster to mainframe

To leave your cibby lookign something like this

Undo 12mm bolts which hold in left and right brake calipers and slide off disk being careful not to chip the paint on your wheel

(you can slide a piece of cloth between the caliper and wheel when sliding off)

Loosen 12mm pinch bolts on left of bike (when looking from the front to the back of the bike)

About now you want to place the bike up on stands. Rearstand is a must, and if you have a frontstand it makes life MUCH easier. I

used PeeDz' stands, so if you need to get in contact with him please click below link


If you dont have a frontstand click below to view Eclipze's "how to prop a bike up from the sump tutorial


Once it's up with no wieght on the front wheel undo main bolt which holds front axle in place

Loosen right hand pinch bolts

Remove front axle and remove wheel leaving the bike looking something like this...

Remove Mudguard (sorry no pic of that!!!)

Loosen Allen Bolts on upper triple clamp to releive pressure on the fork cap

If inserted, remove the two black covers from the tops of the two fork caps

leaving the caps looking as follows

Insert 17mm Allen key took and loosen fork cap

On left fork, undo 12mm bolt which holds in clipon


Undo 14mm bolt on lower triple clamp but hold onto the fork at the same time as it may slide out!!!

On left fork, undo 12mm bolt which holds in clipon

Undo 14mm bolt on lower triple clamp for right fork

In order to remove forks completely a circlip needs to be taken off the forks which can be undone by simply using your nails to

open and slide off fork leg as follows

One both of the circlips have been undone, simply rotate the fork in a clockwise/anticlockwise motion whilst giving it slow

downward pressure until for fork comes out, leaving you with two of the following

Use your 17mm allen key to remove the fork cap [red]*Note there may be a bit of force and the cap may spring up so hold it firmly.

The pressure is not one of those, dont hold the cap and it will hit the international space station type forces, more a oh crap

where'd that f**ker of a cap go.. i know it fell beside me somewhere....[/red]

Once undone you will reveal the spacer, a tube of approximately 15cm in length. pull this out and blow it will be a washer, and

then below that the spring.

Below is the top of the fork spacer tubing

Pour out the oil making sure you catch the spacer and spring.

Once out you will see the following

You can see here the spring, the spring spacer and the washer. Note the colour of the oil which even on this aussie delivered bike

is starting to turn black and sludgy. The oil used SHOULD be a honey colour and not have a horrible odour. For those with grey

imports you will find your oil will actually be black and somewhat mercury like in colour.

Next step is to remove the valving and fork seals. To do this there is an 6mm allen key which holds in the valving unit to the

bottom of the fork as seen in the following two pictures. *this is looking from the bottom of the fork to the top, the axle pinch

bolts will need to be removed here.

The method I have to undo this bolt is to have the fork leg sitting on the ground with one foot on the fork. ie on bended knee with

the fork leg under your front foot. Insert the allen key and use every single piece of energy you have to loosen the masses of

thread locker that has been used here from factory. Be careful of people standing behind you here as you may let out a little

muscle straining fart as you try to undo this bolt. I'm not kidding here when I say this is the hardest bolt you will possibly EVER

have to undo. Once you ear a mighty crack followed by the screaming as you realise you have just skinned your knuckles you can sit

up knowing you have undone the bolt... careful here not to thread the allen bolt.

Once you have applied liberal amount of antiseptic to your hands, you come to the easy part. Pull the fork tube apart and while you

are giving it a bit of outward pressure continue to undo the allen key. If you dont put pressure on the fork leg the allen key will

just turn on itself. You will eventually feel it let go alltogether and you can get the bolt out.

Once you have taken the bolt out you will need to remove the dust cap to reveal the circlip which holds the fork seal in place. If

you look down the staunchion you will see a circlip which holds the fork seal in place.

Use a flathead screwdriver to remove this circlip.

Once the circlip is out, hold the fork lower and staunchion firmly in either hand and pull them apart till it hits the stops. You

will need to use a bit of force here. See pictures below

You will have to do this a number of times and eventually the fork lower and stunchion will come apart leaving you with just the

staunchion looking something like this

Looking at this photo of the staunchion you see the following from left to right. Note the left is the top of the fork leg and the

right is the bottom. First you have the fork seal, then a washer followed by the guide. That's all there is to it.

Pull the old seal off remembering which side of the fork seal is facing up (this is useful when putting on the replacement) and the

washer and guide and this is the time where you degrease the crap out of everything clean it up and let it all dry.

As you can see in the following photo

The staunchion has some light surface rust on it. To get rid of this, use some fine emery paper (im talking 1500 or 2000 grit wet

and dry) and give it a light sanding till the surface rust is gone. If you have bent or chipped staunchions you can buy new ones

for approx $220 at any honda dealership.

Once everything is clean and dry it's time to reassemble. Get your fork lower and staunchion and slide the staunchion back into the

lower. If when you disassemble the forks you see a small thimble like piece of metal, this goes in the bottom of the staunchion

before you slide it into the lower. Once the stanchion is temporarily in place, slide the small spring down the fork tube, followed

by the valving with the pointy side down then screw into place. You may need to temporarily slide the spring and spacer down the

fork to put pressure on the valving as you tighten the allen key.

[red]*** Remember here to use thread locker on the allen key before you screw it in ***[/red]

Also note how tight the allen key was when you took it out. So it may require a bit of force to tighten it aswell!

Once the allen key is tight, you can remove the spacer and spring.

The next part is somewhat tricky. The way I do this probably isn't the correct way but it works for me.

Get some of the new fork oil and wipe it over the fork guide. Slide the fork guide over the staunchion and let it get down into the

lower fork. I now use a flathead screwdriver and hammer to gently tap the fork guide into place as follows.

This may take some time and it's pretty much a case of, a couple of light taps around in circles. The fork guide will slowly slide

into place. Once it is flush in it's spot put the spacer ontop.

Once this is done you have to slide the new fork seal onto the fork stanchion. You have to be VERY careful here not to cut the fork

seal or you have to replace it. The way I do it is as follows. Get some cling wrap and fold it over itself once and then sit it on

the top of the staunchion. Get some new fork oil and wipe some on the fork seal and on the top of the fork and slide it on and down

into place.

[red]*** Make sure you put the fork seal on the correct way here. ***[/red]

You may need to use the old hammer and screwdriver technique here again to get the seal to sit properly. Again light taps and don't

damage the seal. You need to get the seal down enough so that the circlip you took out can sit back in it's seat. Once the circlip

is in, put the dust cap back on, slide the spring in, followed by the washer and followed by the spacer. To end up looking like


Pour in 383ml of your chosen weight of oil. I found the 15w works a treat and is not too stiff.

If you want to do the 20c mod, this is where you would do it. Put 2x 20c pieces on the top of the spacer and put your fork cap on

and tighten.

Before placing the forks back into the bike, put down on the ground and compress a few times to get the oil circulating through the

valving... you will hear air moving through the valves which is normal. This will go away as the air settles and comes to the


Once this is done, slide the forks back into each respective leg and do the removal steps in reverse order to tighten everything

back up.

And there you have it. New fork seals!


Cerby: ive never been to a party where the guys were so comfortable with blow up dolls!
PeeDz: Why.. How many parties have you been to which have had blow up dolls?
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