Mk2 Forks Sticking..?

[Spacemonkey]

My front end has always had a weave above 50mph and never felt stable at all off road which does no good at all for a novice's confidence... I merely put this down to knobblies.

Anyway, out for a pootle along the lanes today so went to fill up with petrol. Whilst waiting for the car in front I did a few compressions on the front end with the brake on and it felt quite sticky, and often it would stick while compressed!!!


Any ideas what could be up? I have neoprene fork socks on which I have never removed (ace idea after destroying my Ducati forks with grit a few years back) but I wouldn't have thought it would be this..

Lack of use? Wrong oil? Is there a way to adjust/measure the air pressure in there..?

[Gwyn]

My front end has always had a weave above 50mph and never felt stable at all off road which does no good at all for a novice's confidence... I merely put this down to knobblies.

Anyway, out for a pootle along the lanes today so went to fill up with petrol. Whilst waiting for the car in front I did a few compressions on the front end with the brake on and it felt quite sticky, and often it would stick while compressed!!!


Any ideas what could be up? I have neoprene fork socks on which I have never removed (ace idea after destroying my Ducati forks with grit a few years back) but I wouldn't have thought it would be this..

Lack of use? Wrong oil? Is there a way to adjust/measure the air pressure in there..?

There should be no air pressure in the forks. Get your bike up on a stand, with the front wheel off the floor, and the forks fully extended (un-compressed). Slacken off the bolts that hold the top of the fork tubes, in the top yoke. ( dont slacken off the bolts on the bottom yoke, or your forks might drop out). Now unscrew and remove the large fork cap's at the top of the forks to release any pressure or vacuum which might be causing sticktion. Put it all back together in reverse Before you try it out, to align the forks, spindle and yokes, slacken the wheel spindle, and the bottom yoke bolts. Now sit on the bike, pull in the front brake, and bounce up and down like fek about 12 times. Gently put the bike on the side stand and tighten the spindle first, and then the bottom yoke bolts. Everything should now be in alignment. Now go and try it out. Good luck

[Spacemonkey]

Thanks, Gwyn. I don't know if there is air pressure in there, I just suggested it as my fork tops have valves on them or so it seems.. H reg Mk2.

[Gwyn]

Thanks, Gwyn. I don't know if there is air pressure in there, I just suggested it as my fork tops have valves on them or so it seems.. H reg Mk2.

The valves are to let the air out, so do that with the the front wheel off the ground, and you wont have to take the fork caps out

[Spacemonkey]

Ah, that sounds better.. so without sounding like an idiot missing it's village, how does the air that requires releasing get in there then?
I shall try the loosening everything tomorrow too.

ps has your bike had it's arse end raised a foot or two? I have long legs so can put both flat on the floor, even after raising the back to what seemed good, but it's not as high as yours!

[Gwyn]

The air get's in past the seals during use, and after while the pressure needs releasing.

No, the rear end of my bike has not been raised. Have you set the "sag" for the rear shock correctly
On my bike, i have set the sag. And the compression adjustment screw on the resovoire(sp) is set to 1 1/2 turns out from fully in.
I am 5'8", about 11 1/2 stone, and cant quite get my feet flat on the floor. I like that set up, but it is still quite soft, and only bottoms out if i land a jump quite hard But that is how i like it. And the front the same, As soft as possible without bottoming out

[Gwyn]

To set the "sag" on the rear shock, check this out..............

http://www.mb1suspension.com/id8.html

[Spacemonkey]

Thanks mate, I'll check that out after fiddling with the front end.

[Spacemonkey]

Mine does look like yours- my mistake..

Loosened axle clamp bolts, fork 'popped' over about a mm or so.. Problem almost resolved.. Released a fraction of air from the tubes too. I'll do an oil change next..

What's the optimum setup for a 12 stone 6'2" novice rider ?

[Gwyn]

Thanks mate, I'll check that out after fiddling with the front end.

On the rear i have got 32mm of free (static) sag, and the compression adjuster 1 1/2 turns out from fully seated (in).

On the front, iam using 5w fork oil (standard), the fork tubes protrude 3-4mm out of the top of the top yokes (the depth of the outer edge of the fork cap), and the compression setting at the bottom of the fork legs are 1 turn out from fully seated (in). Like i said, iam 5'8" and 11 1/2 stone, I find these settings spot on for my riding style, but it's a case of suck it and see Also, i would have thought at 6' 2", you would be more comfortable riding with slightly higher handlebars My Renthals are a standered raise which suit me as i'm a shortass, and 6" shorter than you

[Spacemonkey]

I don't find the standard bars to bad but one day will change them. I ride with bent legs when stood up anyway so it's not too bad. My fork caps are almost flush with the top yoke so that's interesting. Which is the standard fork height?

[Gwyn]

I don't find the standard bars to bad but one day will change them. I ride with bent legs when stood up anyway so it's not too bad. My fork caps are almost flush with the top yoke so that's interesting. Which is the standard fork height?

I would have thought fork caps flush with the top of the yoke, but not 100% sure.

[knackeredMk1]

Come somewhat late to this coould be:

1) Your forks are bent.To check take them off and roll them on a flat surface with only the chromed bits in contact with the surface. You should see if they are bent straight away.

2) Your forks are twisted. (You may have at least partially relieved this already.) Loosen fork clamp bolts and the head bearing nut and twist the wheel/handlebars a little until everything is in line and the forks compress and rebound easily. Then tighten everything up.

3) Yours seals/bushes are really shagged/lack of oil in forks. Try to drain forks and look at the oil.

[Jonorow]

i think knackered has something on the last point, if the teflon coating has worn away then there will be some stiction on the sliders.
another point to think of is, how tight are the bottom yolk bolts? if they are too tight then this will also cause stiction as the clamp the inner leg to the outer leg (been there done it) Jon

[ally]

So after reading some of the fork issues I decided to top up my mk2 forks with some oil, put bike on pit stand lossened top yoke undone cap on top of fork, well that little bugger just didn't wanna pop off. It feels like it's attached to the spring or something! Am I being a dumb arse?
I persume they are showa, usd, gold on the top part of leg.
any advice please Ally