Steering / Head bearing - how do you keep it tight?

[bikerpet]

Next little problem.

The steering bearing on the '21 RR is a complete Houdini at getting loose.
I thought I had it licked by over-tightening the bearing a little, clamping down the top tree bolt hard, clamping the forks then backing off the bearing against the top tree.
But no. Loose again. Considerably.
It's a mystery to me how it can do that!

My next thought is to put a thin rubber washer (I've some 1mm insertion rubber) between the tree and the main nut, then repeat the above process. The hope being the rubber will act to take any movement between nut & tree and also stop the nut rotating.

Anyone else got any tricks?

Edited October 23, 2023 by bikerpet

[feetupfun]

You've got me thinking.

Doesn't the top triple clamp pull down against the adjusting nut?

[bikerpet]

15 minutes ago, feetupfun said:

You've got me thinking.

Doesn't the top triple clamp pull down against the adjusting nut?

Yes, that's why I can't work out why it's so darn hard to keep it tight!
I used to just tighten the main nut then the top bolt and finally the fork legs. But it always loosened.
So last time I greased it I decided to tighten the bearing right down until the steering got stiff to turn, then tighten the other parts and finally back the main nut off hard against the top tree. Today it was rattling around like ... a loose thing.

Beats me how it happens!

I've heard others say they have the same trouble.

I do note that on the latest model they've changed to a steel nut instead of the aluminium. Maybe that's the solution?

Edited October 23, 2023 by bikerpet

[faussy]

Does the trs top triple clamp have a centre pinch bolt on the top locking nut. This loosens on my gasgas quite a lot and then the nut backs off.

Next time i would mark your lower locking nut and see if its backing off over time or the bearings are just setting in after being greased

Edited October 23, 2023 by faussy

[bikerpet]

6 hours ago, faussy said:

Does the trs top triple clamp have a centre pinch bolt on the top locking nut. This loosens on my gasgas quite a lot and then the nut backs off.

Next time i would mark your lower locking nut and see if its backing off over time or the bearings are just setting in after being greased

No pinch bolt.

Good plan to mark the nut.

It's always loosened off, even before greasing.

[bikerpet]

I marked the nut as suggested.

It's definitely backing off, almost a whole turn in under 10 hours.

Beats me how it does it!
I tightened down the headset until it was starting to bind noticeably, clamped down the upper tree using a 19mm spanner on the top bolt, clamped the forks then backed off the headset nut firmly against the top tree until the headset moved freely again. So where does it get the slack to loosen further? Mystery.

I'll have a go at fitting a thin rubber washer between tree and nut.
Or maybe thread lock, although that seems a little risky on such a large diameter alloy nut - could make for a fair battle and faffing about with heat to get it undone later.

I'll try marking the top bolt this time - maybe if that loosens then the tree can start to lift. Although to do that it either needs to slide up the fork legs, or the legs have to slide up in the lower tree. Those bolts are all torqued to the upper suggested value and I always clean the legs and trees with brake cleaner before installing to be sure there's no oil in the clamp area.

[Tr1AL]

14 hours ago, bikerpet said:

I marked the nut as suggested.

It's definitely backing off, almost a whole turn in under 10 hours.

Beats me how it does it!
I tightened down the headset until it was starting to bind noticeably, clamped down the upper tree using a 19mm spanner on the top bolt, clamped the forks then backed off the headset nut firmly against the top tree until the headset moved freely again. So where does it get the slack to loosen further? Mystery.

I'll have a go at fitting a thin rubber washer between tree and nut.
Or maybe thread lock, although that seems a little risky on such a large diameter alloy nut - could make for a fair battle and faffing about with heat to get it undone later.

I'll try marking the top bolt this time - maybe if that loosens then the tree can start to lift. Although to do that it either needs to slide up the fork legs, or the legs have to slide up in the lower tree. Those bolts are all torqued to the upper suggested value and I always clean the legs and trees with brake cleaner before installing to be sure there's no oil in the clamp area.

Steering rod /pin/ axle pulling upward through its hole in the lower triple tree ?.

[bikerpet]

I believe (and it looks that way to me) that the pin is flanged at the bottom, so it can't pull through. So I very much doubt that's the problem.

I've fitted a 1.5mm rubber washer above the main nut. Only a couple of hours up but so far it hasn't moved.
Perhaps a wave or conical washer might be a more "engineered" solution.

I did notice that the top bolt taper does not mate perfectly with the countersink in the upper - there is only a very thin wear mark in the red anodising where they contact. That could be part of the problem - the taper should help lock it up, but if it's not accurately mating then it wont work like that. I'll keep an eye on that bolt to see if it loosens.