Fork Installation sequence for 990

[Dagwood_55]

Rebuilt forks in the mail, be here any day.

I got the torque spec's out of the OM.

But is there a tightening sequence for the top and bottom tree and the axle clamp bolts.

Or, in what order do I tighten the bolts??

[Katoom119]

No set order but with any pinch bolt system you need to tighten the bolts equally.

Take the top tree, left side. Should have two pinch bolts. You don't crank down on one all the way. Tighten it a couple of turns, then go to the other bolt and tighten it a couple of turns. Work back and forth this way until both are at the correct torque spec.

When you're done, you should find that the space between the two sides of the tree is equal. That's when you know you did it right.

[Dagwood_55]

Thanks, Looking for my SPS forks and shock on monday or tuesday. Can't wait to get it going..

[Dustodust]

There is a sequence and it does make a difference. It allows proper alignment of the axle plane in relation to the rear .
Improper alignment could cause fatal high speed wobble. Fork alignment should also be redone after a crash or spill.
the steering head should also be adjusted properly in sequence . First the bearing load is adjusted (similar to a wheel bearing) then the pinch bolts for the steering head should be snug tite until after the fork tubes and wheel are assembled , then after alignment the pinch bolts are fully torqued.
the factory manual calls out .the tightening sequence.
the axle tightening is part of fork alignment and is critical
I can look it up for you but IIRC here is how I do it from memory (open to correction from experts)
adjust the steering head, pinch bolt snug tite( loose but fairly firm and seated)
install the fork tubes snug tite , with whatever geometry setting of level past top clamp you prefer(adjusting level past top can have very profound results)
install the front wheel,
install the axle , then tighten the pinch bolt on the axle side, install axle nut and nut side pinch clamp snug tite (loose but seated)
face the bike with front wheel between knees and lightly move the bars back and forth to align and seat faying surfaces.and eyeball the bars straight .
tighten the top clamp nut down to seat it properly then back off slightly, then tighten steering head pinch bolt , then tighten top clamp nut (tightening top clamp nut before pinch bolt will not allow proper pinch)
then torque fork leg clamps ( I recommend the skill method of torque over the torque wrench, others prefer torque wrench) overtightening the lower fork leg clamps could result in fork stiction
then tighten the axle nut fully , followed by the final pinch bolt (tightening pinch bolts first could allow the axle to be actually loose but seem tight causing speed wobble)

IMHO front fork alignment is an often overlooked or improperly performed critical safety item and factor of suspension handling characteristics, often contributing to wobbles if not performed correctly it could result in serious injury or death

my $.02

[Katoom119]

If all he's done is pull the fork legs to be rebuilt why would he have to full with the steering head and the top clamp nut? You just pull the wheel, loosen the pinch bolts to the triple clamps, and slide the fork legs out. Am I missing something?

Other than that, I agree with you. Those are much more in depth directions.

[FakeName]

what's the sequence when just the wheel has been off?

[Dustodust]

Originally Posted by Katoom119

If all he's done is pull the fork legs to be rebuilt why would he have to full with the steering head and the top clamp nut? You just pull the wheel, loosen the pinch bolts to the triple clamps, and slide the fork legs out. Am I missing something?

Other than that, I agree with you. Those are much more in depth directions.

correct
however, ' how do we know the triple clamps are in alignment with no twist or properly torqued
the bearing load may not need adjustment, although its a good time to check, but the steering Top Clamp pinch bolt bolt definitely

sure you can just bolt it up "if you feel lucky today" but OP asked about the sequence
you can just throw the front wheel on and crank it down too ,and everything may seem just fine there, not realizing it is a contributor to potential wobble problems along with , tire balance, tire size and rim width, relative shape of tire profiles, loose motor mounts, loose swingarm bearings, loose spokes, wheel bearings, wheel alignment and the biggie: Sag height relation between front and rear, for instance if you have a lot of weight loaded on the rear it may help to raise the fork legs in the clamps so the caps are over the top more, or the other way if you have a taller rear tire or saggy fork springs
it all adds up

[Dustodust]

Originally Posted by FakeName

what's the sequence when just the wheel has been off?

axle first then pinch . Just remember the concept is to allow the axle to tighten against the spacers before being clamped into position

[FakeName]

Originally Posted by Dustodust

axle first then pinch . Just remember the concept is to allow the axle to tighten against the spacers before being clamped into position

But..how does the axle nut torque if the pinch bolts are not tight?

thanks.

[Katoom119]

Ok, I'm with you. If it's a "check while you're in there" type deal then I agree with that.

[crofrog]

Originally Posted by FakeName

But..how does the axle nut torque if the pinch bolts are not tight?

thanks.

tighten the right side pinch bolts, torque axle, loosen right side pinch bolts, bounce forks through travel. torque pinch bolts.

[FakeName]

Got it thanks.

[MotoTex]

One thing I would add on fork install steps:

Align the forks in the tree so that the axle holes in the fork line up. I have found that on my bike if this isn't done, then removal of the front axle can become a pain if one fork leg is applying just a little spring pressure.

The way I do this is with the wheel in place and supported to line up the axle hole in the hub with the RH (Axle side) fork leg, which is clamped so it cannot move in the tree. I then adjust the LH leg up or down in the tree to get the alignment spot on, then clamp that fork leg as described above.

It can take a few minutes of fine tuning to dial this in, but this has been worthwhile in my case. It is usually just a millimeter or two difference in how high one of the fork tube comes out of the top tree. My guess is that this is due to slight variations between the springs length or other manufacturing tolerances in the forks.

If you have ever had problems removing the axle, try making this adjustment next time you have the opportunity. Once I made this change the axle was significantly easier to R&R.

I'll be doing this assembly again tomorrow evening after I pick up my reworked forks.

Thanks for the refresher on all the steps!

[crofrog]

If your fork tops are even but the axles dont line up your forks where improperly reassembled the fork cap needs to bottom out against the dampening rod.

[MotoTex]

Originally Posted by crofrog

If your fork tops are even but the axles dont line up your forks where improperly reassembled the fork cap needs to bottom out against the dampening rod.

Thanks for that bit of info!

Then, as SNL's Emily Latella would say, "Oh? Never mind"

That adjustment was done on the forks as they were from the PO. They weren't off by much.

I know he mentioned having heavier springs installed, and may have had other work performed that resulted in the imbalance.

Hopefully they'll be even at the axle this time, after being rebuilt and re-valved by a professional suspension shop.