Give your front end a fresh feel.

[fuzz]

Noticing that there is nothing specific in the Workshop guides on forks, I thought I would share my experience of a basic overhaul. My fork oil has never been changed, and the bike is now 5 years old, so the job was well overdue.

I'll be basing everything on the SV650S, but the procedure should be pretty much the same for any bike with RWU forks. You should remove the front fairings first, but I have enough access to not have to bother. First things first, wheel removal.

Using an Abbastand and jack (homemade, see pic!) raise the front wheel off the floor. Remove the caliper bolts and slide the calipers off the disc. Tie them up out of the way and so they are not held by the hoses. Slacken the axle clamp bolts, then undo the axle bolt and carefully remove it. I had to use a drift from the other side. Make sure you keep the spacer(s) aside and the speedo drive if you have one there. Lean the wheel against a wall/fence keeping any weight off the brake discs. Then remove the mudguard.

On the SV, there is a clip held on the underside of the mudguard which holds the speedo cable. Remove this (if there is one) and then remove the bolts holding the mudguard in. Remove the mudguard. Then remove the bolts holding the brake cables to the forks and the speedo cable if there is one. The front end should now look like this.

https://img130.imageshack.us/img130/4112/start5hg.jpg

Now remove the forks, one at a time. If you have clip ons, slacken the clamp bolts. Slacken the fork top bolt, as this will be easier to do now than when the fork is removed. Slacken the clamp bolt on the top yoke. Then slacken the clamp bolts on the lower yoke, and pull the fork out.

https://img78.imageshack.us/img78/519/fork4ud.jpg

The spacer and spring need to be removed next, before draining out the old oil. Undo the top bolt carefully as it is under pressure from the spring. It shouldn't fly off, but be ready to catch it when the thread no longer holds it. Compress the fork and remove the spacer. You can now either use a metal hook to pull the shim/spring out, or you can tilt the fork over a drain pain and catch them as they come out. Pump the fork to force out the old oil.

https://img111.imageshack.us/img111/4789/oldoil1cu.jpg

Leave the fork upsidedown to get as much old oil out as possible. Clean the spring, spacer and shim while you wait. Once all the oil is out of the fork, you need to fill up with the required oil. I'm going for the standard stuff, 10W. Pour the oil in with the fork fully compressed, until you have the right air gap. This is measured from the top of the fork to the top of the oil. The SV is 104mm. Pump the fork a few times to get it into all the right places until no more air comes up through the oil. Measure the air gap again and add/remove oil until it's correct.

https://img124.imageshack.us/img124/6597/internals3vy.jpg

Extend the fork fully and insert the spring, followed by the shim. If you are replacing the spring with an aftermarket one, you might need to use a different spacer, before placing it in the fork. Use a new O-ring on the top bolt (I didn't, it was in perfect condition) and smear it with new fork oil. Use some force to screw the bolt in as you need to compress the spring. Tighten it loosely. Do the same with the other fork.

I used this opportunity to give the forks a quick clean up. In true Haynes style, installation is the same as removal. I decided to drop the yokes through the forks a little to quicken up the steering, or at least to experiment. 2mm shouldn't change much, but I'll test it out and see what it's like. Make sure both forks protrude the exact same amount as each other. They should be measured from the fork itself, and not the top bolt, in the same way as the air gap.

And there you have it. It only took about an hour and a half (rain kept stopping play) and was very straight forward to do. Go on, freshen up your front end.
____________________
https://www.bikepics.com/members/fuzzbcf/
Bikes: '99 NSR125R, '00 SV650S, K1 GSX-R600, '97 CB500, K3 SV1000S, '16 VFR800

[Visitor Q]

[fuzz]

I thought it was penifresh
____________________
https://www.bikepics.com/members/fuzzbcf/
Bikes: '99 NSR125R, '00 SV650S, K1 GSX-R600, '97 CB500, K3 SV1000S, '16 VFR800

[Whosthedaddy]

After reading your post on changing fork seals, I thought jobs a good I'll have a go myself, then I read this and thought fook that. When I was removing the end cap (dont ask me why) before the forks were removed, and nearly getting an eye full of coil, I am having a real job getting the spring compressed and end cap done up again. I dont have access to a vice, and leaning on it and trying to turn the cap is quite a tricky manoeuver

I know that the FZR forks need 43.5ml of fork oil, will I still have to measure the distance from top to coil, if I can place the exact amount of oil in? I am worried that buy compressing the coil to reinsert the end cap will disturb any space previously measured
____________________
Current : MSX 125 Past : CBR 900RR Monkeybike : c50 LAC : ZXR750 H2 : FZR600 : ZX7R P3 : YW100 : TRX850: Trophy 900 T309 : GSXR 600 L0: Monkeybike : XJ6S Whosthedaddy

[Kickstart]

Hi

Fork oil levels are generally measured with the forks fully compressed and no springs in them. The actual level with the springs in place and the forks extended will be very different.

All the best

Keith
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Traxpics, track day and racing photographs - Bimota Forum - Bike performance / thrust graphs for choosing gearing

[Whosthedaddy]

So, as long as the coil is out, the old oil out and the fork compressed as far as it will go, by putting the correct amount of oil in (in both forks) should be ok
____________________
Current : MSX 125 Past : CBR 900RR Monkeybike : c50 LAC : ZXR750 H2 : FZR600 : ZX7R P3 : YW100 : TRX850: Trophy 900 T309 : GSXR 600 L0: Monkeybike : XJ6S Whosthedaddy

[Kickstart]

Hi

Yes, if you have got all traces of the old oil out. Fork oil level in the Haynes is given as 101mm for the FZR600 (ie, fork compressed, also spring, distance from top of fork to oil level).

All the best

Keith
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Traxpics, track day and racing photographs - Bimota Forum - Bike performance / thrust graphs for choosing gearing

[Whosthedaddy]

Theory sounds ok, now lets try the practical
____________________
Current : MSX 125 Past : CBR 900RR Monkeybike : c50 LAC : ZXR750 H2 : FZR600 : ZX7R P3 : YW100 : TRX850: Trophy 900 T309 : GSXR 600 L0: Monkeybike : XJ6S Whosthedaddy

[Jack_Cheese]

I'd just like to add - check your yoke bolts after 20 or so miles of riding, and check the forks are at the same level. Check it a few more times untill you're satisfied they ain't budging Mine slackened, causing my right fork to slip about 10mm through the yokes.

I think i'll be using loctite next time

How many miles have you put on it to turn the fork oil black!?

Jack
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www.bikepics.com/members/jackcheese <--- NOW FOR SALE! 51 Plate Cagiva Planet 125
Quacker_boy: "Jack, you really are a dick!"

[Whosthedaddy]

Mine was black and smelly but then again my bikes 17 years old
____________________
Current : MSX 125 Past : CBR 900RR Monkeybike : c50 LAC : ZXR750 H2 : FZR600 : ZX7R P3 : YW100 : TRX850: Trophy 900 T309 : GSXR 600 L0: Monkeybike : XJ6S Whosthedaddy

[fuzz]

Well my bike was only 5 years old and that was plenty long enough to turn the oil black. Fork oil is generally smelly anyway, even fresh stuff (dont take a whiff when you open the bottle )

When you put the fresh oil in, make sure all the air comes out first, then remeasure the air gap, before replacing the springs. Just pump the forks 10 or so times, and it chould send the oil to all the areas.
____________________
https://www.bikepics.com/members/fuzzbcf/
Bikes: '99 NSR125R, '00 SV650S, K1 GSX-R600, '97 CB500, K3 SV1000S, '16 VFR800

[Whosthedaddy]

Had a go at replacing the oil in the forks today, not as scary as I thought, in fact apart from one little incident, it only takes 30 mins per fork and that includes the dismantling and reattaching to the bike

The fork broken down on the left and a newly refilled one on the right

https://www.bikechatforums.com/files/fzr600_060.jpg

The diffrence between new 10/30w oil and the old smelly stuf, I'll let you guess which one is which

https://www.bikechatforums.com/files/fzr600_059.jpg

After measuring 435ml of fluid, be patient when pouring it in the fork as it takes time for it to sink to the bottom, nearly had it all coming over the top . When the oil is in, gently lower the coil in (with the tighter coils at the bottom) and gently masturbate the outer tubing of the fork up and down. You can actually feel the oil moving .

With the shaft in and the cap on, the difference was untrue. The compression in the new one felt, well new, and the old flacid one was as soggy as a fat chicks muff in a heat wave.

I was intending to change the fork seals, but chickened out for now, the dust seals are ok, so the proof will be in the riding

Cheers fuzz for an easy to follow guide
____________________
Current : MSX 125 Past : CBR 900RR Monkeybike : c50 LAC : ZXR750 H2 : FZR600 : ZX7R P3 : YW100 : TRX850: Trophy 900 T309 : GSXR 600 L0: Monkeybike : XJ6S Whosthedaddy

[craigs23]

Is it wise to leave the callipers dangling like that?

[Dom_]

Probably not, but i've always done it, and i can't see it doing any real harm unless you start tugging on them.

[fuzz]

[stevo as b4]

Nice pics and a good write up there! I was thinking about doing a front fork overhaul myself on my KMX200, as i thought it would be interesting to learn how to do it, and save me £100 or so. Iv'e decided against it now though, as i can't be sure that the fork tubes are straight, and i will need new fork seals, springs, and possibly some re-valving work, to firm the action up a bit, seeing as my bike will be a supermotard sort of thing when it's done. Anyway paying someone else to sort out the suspension seems a good idea now, as im very lazy, and i think just stripping and re-building the bike with new parts, and tackling a full engine re-build will be more than enough work, and give me more chance of actually finishing the bike sometime this year!

[st3v3]

ok, read all that and was educated!, but is it a similar procedure for the fork seals, or am i being incompetent?


is this where i find haynes manual out/look up service manuals etc..
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Roger wrote: Women don't get damp for clingy puppies. Get some better happy pills, hit the gym & buy a medallion the size of a dinner plate. Job done

[Gazdaman]

Fork oil in my TZR smelt like puke, it was nasty.

Anyway, you don't always have to take the forks out, some have a drain bolt in the bottom of the leg.

Gaz

[KTM Gordo]

Something else that can make a difference, especially on higher mileage 'bikes, is replacement fork springs. I replaced the standard Fazer springs with Hagon progressive ones - and it was like someone had ironed the roads - much smoother, less bouncy and much much more comfortable.

It's not an expensive part either - about £60 if I remember right.

HTH
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Change is inevitable - except from a vending machine.

KTM 990 Adventure | KTM EXC 250 Racing | Land Rover Freelander SE Td4

[sqarider]

any chance we can get the pics back ?
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FSZ600/2000 ; XV750/1991