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View Full Version : Fork oil topping


stef
21-03-2005, 01:15 PM
before i look into the book of lies, can anyone enlighten me on the procedure for checking/topping up the fork oil ? it looks really straight forward (remove big bolts, top up, refit big bolts..) is it that simple ?

A Yerbury
21-03-2005, 02:08 PM
I think you remove the big bolts, then remove something else, then make sure it does'nt explode...if it is that easy, let me know as mine are leakier than a tramps gusset.

The Kevlar Kid
21-03-2005, 05:38 PM
You'll need to drop the legs out, and pull the springs and spacers out from inside so you can measure the oil levels properly - not worth guessing (imho). It's a bit of a pain, but should only take 1-2 hours to do.

stef
21-03-2005, 05:46 PM
You'll need to drop the legs out, and pull the springs and spacers out from inside so you can measure the oil levels properly - not worth guessing (imho). It's a bit of a pain, but should only take 1-2 hours to do.
that sounds a right pain without a center tand..

A Yerbury
21-03-2005, 06:43 PM
so darling...but do you listen? I mean do any of you bloody listen?! with your "oh its Yerbury with his marginally offensive, never been out with the the nottingham massive, getting all laa de daa with that Richard girl....and occasionally being a bit technical" ways, damned bloody fools the lot of you, many of you as ugly as geese and as bloated as last weeks ham hocks, by god damn you all to high heaven.... Apart from you stef. Get a jack and take the bas tards off that way? its easy. Does it really need doing though cher steph? or are you being a bit of a worry merchant?
All the noise.
AY.
salut.

stef
21-03-2005, 07:09 PM
Too right, it DOES need doing, since i have bought a litre of fork oil !
why would have i bought the oil, if it didn't need topping up ? do you think i am a fool ? french maybe, but a fool ? am i wearing a joker's hat with little bells on the ends ??? i think not.
umm.. seriously, i get the idea.. messy.
The only reliable way to find out if it needs doing is by checking it.. I havent checked it since i bought the bike, and i feel a bit of a "glitch" on pressing the brakes hard when stationanry (the classic fork press test)..

PaulS
21-03-2005, 07:19 PM
If you're going to go to the trouble of taking the forks out and removing the springs, etc..., you may as well change the oil completely for the new stuff. According to the maintenance schedule for my bike it should be changed every two years anyway. Put in the amount it says in the manual and use a dipstick to check the levels.

A Yerbury
21-03-2005, 07:25 PM
"The only reliable way to find out if it needs doing is by checking it.. I havent checked it since i bought the bike, and i feel a bit of a "glitch" on pressing the brakes hard when stationanry (the classic fork press test).."


err see below..! they are a bit "glitchy" as standard or so I hear.

spacemonkey
21-03-2005, 07:45 PM
Now listen up: it is possible to change the fork oil and replace without removing the forks. I've seen/had it done. Firstly be very wary when you undo the top bolts of the fork caps, as when they go the bike drops suddenly on the forks and the bike will fall over due to the new unbalanced status of the bike to the right. Not good... Anyway, back to the plot. You remove the oil with a syringe and tubing. Easy. Then you phone someone like http://www.davewoodracing.com/ who has experience in such matters (in fact it was he who demonstrated this to me...) to find out how much oil to put in. If you can't get oil volume then he did once rebuild a fork with oil correctly, then he measured the oil level when the fork was compressed in the bike as I have described. He got a metal rod and put a zip tie on it tight and set it to the correct oil level height. He then used it as a dipstick to get the correct oil level, sucking excess out with the aforementioned syringe. Remember to compress and uncompress the forks a few times before measuring the level to allow the oil to circulate and not give a false reading. Worked for me!

A Yerbury
22-03-2005, 09:13 AM
More tube and syringe fun from space! top tip, so in theory a padddock stand and a jack/bit of wood combo would be just the ticket?

The Kevlar Kid
22-03-2005, 11:38 AM
[QUOTE=spacemonkey]Now listen up: it is possible to change the fork oil and replace without removing the forks.QUOTE]

Spacemonkey does not lie - indeed it is possible and this is the way race bikes are usually set up when they are playing around with oil levels etc to change the damping properties (somebody please correct me if I am wrong).

From a novice point of view (and I've only done four or five changes / strip and rebuilds myself so I'm no expert) if you do it this way, make sure you get the oil level measurement from someone reliable - as you wont find this in a Ducati or Haynes manual. When getting this level, ensure to check where it should be measured (e.g. front / back / centre of forks) as they will not be vertical whilst they are still mounted in the yokes, so the height of the oil will vary in these positions. Realise in advance that to get the tops back on afterwards you will need to lift the front of the bike up the sliders with one hand, whilst trying to screw the top back on with the other (without cross threading it) - might be best to get some help with that bit. Finally remember to syringe out all the old oil, including compressing the damper rod a few times to expell it from there - probably also best to tie a bit of cable round the top of this so you can get it back when its slid down into the tube.

As an aside from the above - I use an engineers sliding set sqare to measure the level (available B&Q etc). Most books show a standard steel rule, but I don't trust the opportunity for paralax error, with the set sqaure you can set the height precisely, it provides a perfectly flat surface to rest on the fork tops, and you just add oil until you see it meet the bottom of the rule - any over filling will measure as with a dipstick.
If your feeling flush, you can buy syringe type levelers that have a straight metal tube with a platform that can have its height set as required, you then simply overfill, insert your tool (oo-er misses) and suck out the unwanted fluid.

I've always found it easier to just remove the legs. Providing you have a centre stand or a jack it only takes a few minutes - but does mean you have to take the front wheel off etc - I use this as an opportunity to give the front end a good check (brakes bearings etc) especially as this would be done as part of a service.

I'm waffling now.......

If anyone disagrees - please tell me and hit me over the head with something blunt.......

The Kevlar Kid
22-03-2005, 12:36 PM
I think you remove the big bolts, then remove something else, then make sure it does'nt explode...if it is that easy, let me know as mine are leakier than a tramps gusset.

Alex - go on get them off (the fork legs that is.....) If your seals are leaking they are easy to do..... (use the old seal as a seal driver if you dont have one.)

The Kevlar Kid
22-03-2005, 12:42 PM
I havent checked it since i bought the bike

If its not been leaking then I would presume the level is ok.

If the oil hasn't been changed for the last couple of years it probably needs changing anyway. If you have the tools, space and time its not as difficult as it may sound. Just give yourself plenty of time to do it.

A Yerbury
22-03-2005, 12:51 PM
Alex - go on get them off (the fork legs that is.....) If your seals are leaking they are easy to do..... (use the old seal as a seal driver if you dont have one.)

Well they were done in January, I had to sign a disclaimer as the tubes themselves are pittied (although you need ninja mechanics fingers to feel it as it seems as smooth as a babies bottom to me?!) 6 weeks later they were both dripping again.

PaulS
22-03-2005, 01:00 PM
Well they were done in January, I had to sign a disclaimer as the tubes themselves are pittied (although you need ninja mechanics fingers to feel it as it seems as smooth as a babies bottom to me?!) 6 weeks later they were both dripping again.

If your forks are slightly pitted but you don't want to pay for re-chroming, an old trick is to fill the pits with araldite and smooth off with very fine abrasive paper (obviously taking care not to sand off the chrome). You will probably need to renew the seals again afterwards.

stef
22-03-2005, 01:33 PM
dammit.. it wasnt that complicated on my jap bike ! i could even use a bycicle pump to play about with them..
looks like a job for next winter then.

A Yerbury
22-03-2005, 01:54 PM
If your forks are slightly pitted but you don't want to pay for re-chroming, an old trick is to fill the pits with araldite and smooth off with very fine abrasive paper (obviously taking care not to sand off the chrome). You will probably need to renew the seals again afterwards.

to do a proper job I would need to take the tubes out, re seal as you say and do the araldite trick the trouble is they feel smooth all over to me? I would end up aralditing the lot then spending two days with a wet dry as soft as velvet...we will see, cheers all the same though.
Alex.

The Kevlar Kid
22-03-2005, 02:14 PM
Well they were done in January, I had to sign a disclaimer as the tubes themselves are pittied (although you need ninja mechanics fingers to feel it as it seems as smooth as a babies bottom to me?!) 6 weeks later they were both dripping again.

Are you sure the seals haven't been put in the wrong way up?

When I bought my bike it was obvious that one seal had been done as the top nut was marked on the corners. However after a couple of weeks this started to weep. I decided to replace the seal myself - being careful to replace the seal the same way up as the one that came out (with the metal spring facing down / away from the oil) I also checked this with a book somewhere and it seemed correct.

After a couple of weeks it started to leak again, so I decided to do it again. By this time I had my Ducati manual. This states that the lettered face of the seal should point down - thus my seal was upside down. I put the new seal in the right way up and its now as good as a nun after morning prayer.

The Kevlar Kid
22-03-2005, 02:23 PM
dammit.. it wasnt that complicated on my jap bike ! i could even use a bycicle pump to play about with them..
looks like a job for next winter then.

?? I'd have thought it was the same on all bikes. Perhaps I'm overcomplicating this.

I think on my ZZR I could get the springs out in situ as they were longer and I definately remember doing a spring kit on it with them still on the bike. I believe I took the oil measurement in the middle trusting this to be the most accurate point for measurement whilst on a slant. Most of the below still applies though.

Unless someone more qualified suggests something else. Wheres Spacemonkey or CK&AK when you need them.....

A Yerbury
22-03-2005, 02:37 PM
well I will be back in the uk with a paddock stand and a jack etc in a few weeks so I will have a look then. But the last fella that did the seals pretty much said " I can fix the seals but that feels a bit worn to me they may go" ....sure enough this way I hope to get an ebay steal and can then yank the forks back with the clip ons under the yokes. This will officially be the coolest thing in the world, and you may all swoon to death but it must be done oh yes.

crust
22-03-2005, 06:18 PM
This will give you a rough idea of whats involved even if your forks arent identical.

Instead of the factory seal driver I have used a piece of plastic pipe from B&Q.

http://www.mcmototech.com/virtual/SHOWA.HTM

:) Crust

stef
22-03-2005, 07:04 PM
umm.. ok.. thank you very much for all this..that link is going to be really usefull.
it is definitely not the 10mins job i was thinking off. at first, looking at it, i though.. "bummer, i'll have to take the handle bars off to get to those nuts.. thats at least 5mins wasted."
how far off the mark can you get. thanks for the reality check.

The Kevlar Kid
22-03-2005, 07:34 PM
This will give you a rough idea of whats involved even if your forks aren't identical.

http://www.mcmototech.com/virtual/SHOWA.HTM

:) Crust

I think these instructions were written by someone with a fetish for making things out of wood.....

Stef, I managed to change my seal with a socket set, two allen key sockets, a couple of screwdrivers, a set square, a 17mm spanner and a torque wrench. Oh, and something to cut the old seal in half so I could use it as a driver. (crusts tip on the plastic pipe seal driver is one I've heard before and it's a good'un)

As your only checking / replacing the oil you won't even need all that.

If your fairly handy with a spanner (e.g. you can do your own servicing) then you can probably do this. If the thought of changing oil, filter and plugs fills you with dread - pay someone else to do it.

spacemonkey
22-03-2005, 07:58 PM
Stef, if you want to do The Spacemonkey Method, then give Dave Woods a bell first and he should come up with the oil levels that you require. It is quite simple done this way, and i had no trouble doing the top cap up again after, I just lifted the front end via the bars and finger tightened the cap. You shouldn't need to remove anything inside the fork leg from what I remember, excpet the oil of course...

stef
22-03-2005, 08:12 PM
i am pretty sure i'll manage, it's just the logisitics of it all that bother's me. i'll have to more time that i thought i would need... it will have to wait..