Head bearings - Procrastinating

[dogshome]

I've been putting this off. My heart says take them out and change them as the old girl is not stable on the motorway at high speed. She was.

My head says that I can't feel any play left right, up down or notching with the front wheel off the ground. The steering falls to the left or right when nudged off centre as expected.

I'm thinking any notchiness would only show itself under load. I know i'm going to have to take it apart, but just to satisfy my head - is there a test I can do. I don't notice any notching when riding, but there are no other suspects.

[Barry]

Are the head bearings tight enough to create some damping without being so tight they induce a slow speed weave ?  The BMW method is to measure the rotational torque required to move the forks from 20 degrees off centre, back to the straight ahead position.   My BMW workshop manual rather unhelpfully describes this method with a note to refer to the torque value in the specifications but the figure isn't there. Someone must know it though.

You may have already done these things but I'd also check tyre pressures, fork damping, wheel bearings, rear suspension and swinging arm bearings.

[skippyc]

I had to change mine as the grease had hardened and the rollers were locked in place and just skidding in the shell.
No matter what tension I used it just didn't work.

[georgesgiralt]

Hello,
I second that. Mine where "new" (as per mileage, but very old from age). The grease was seizing hard the whole bearing.
I cleaned them (with Diesel fuel) and lubed the roller back and the problemS disappeared.
But, given the cost of new bearings and the work involved in getting to them to clean/grease them is the same to the work involved to replace them, I wold buy a new set and replace.
Just my 2¢

[Matt Chapter]

I agree with Georges, if you're going in that far, and considering we're about 40 years into the age of the bike, if you've got it apart, just replace them.  It's a project (I'll have someone else do) on mine coming up in the next couple years, if I don't sell it.

[dogshome]

....

[georgesgiralt]

Good !
Now; put the bike on the centre stand and proceed ! 

[Tony Smith]

Check your front wheel bearings.

If they are OK work your way South - swingarm bearings, rear wheel bearings.

Outside possibility - how old is the front tyre?

[dogshome]

Good !
Now; put the bike on the centre stand and proceed ! 

 

[dogshome]

Check your front wheel bearings.

If they are OK work your way South - swingarm bearings, rear wheel bearings.

Outside possibility - how old is the front tyre?

Did wheel bearings last year and could not feel anything whilst checking head bearings, but will give her a spin.

Also greased and adjusted rear swing arm 2 years ago, but will have a pull on that. Rear wheel bearings were checked and regreased and will spin that too now. Both tyres new and properly inflated.

2 days of rain and missus at work this weekend, so will bite the bullet unless another bearing reveals itself.

[dogshome]

  uh? What? it's nearly spring??!!!! 

Dissassembly has started. Forks out, gauge cluster tied back, brakes tied back, top nut undone with my biggest impact gun. So, just trying to weedle the centre RT fairing bit out and then can hang the bars up to the roof. The plan being to do this without dicaonnecting brakes, clutch, throttle or much else 

I've not touched the top nut before and it is a bit mangled. Hence going straight to impact gun. A very close stainless replacement appears to be M22x1.5 pipe fitting plug. It is slightly taller in the head (that has zero effect), but the same in no# of threads. Also new and shiney 

[dogshome]

Jiggered :-)

[dogshome]

It's worse than that, it's dead Jim, dead Jim, dead Jim.....   

[dogshome]

Without wanting to start an oil thread, I have a selection of greases to put in:

1. My go-to Silkolene Pro RG2 synthetic red grease. Fairly stiff, very slippery, mostly water proof. Never had to change a bearing after using this stuff.
2. Moly CV grease. I have this after some difficulties with a horrible plastic boot that the PO fitted to my car. Good for low movement, high pressure, but technically a bit runnier.
3. Molycote BR2. This is also fairly stiff and intended for high pressure.
4. ROCOL Dry moly paste. Great for splines, probably not the right trousers here though.

It's a toss up between 1 and 3. The bike is faired, so water isn't an issue. It would be on an unfaired bike as there are no seals. On the R65, water can also run down the centre nut, down the tube and through the steering lock cutout into the lower bearing! I have a new stainless hydraulic plug that doesn't have the hex hole all the way through to be sure.

[Bob_Roller]

I did a bit of possible 'improvement ' on greasing steering head bearings .
There are, or should be two plastic plugs on the front side of the steering stem .
They are for attaching a fairing .
I put two grease fittings in those threaded holes, I think they are 6 mm .
I got a length of threaded rod put it through the hex hole on the steering nut .
I put a large rubber washer on then a large area washer and a nut .
Did the same thing on the bottom where it comes out of the steering head .
I filled the entire cavity with grease until it came out from around the bearing areas .
Once year I pump a little grease in until I see it come out .
I removed the grease fittings and reinstalled the plastic plugs .
It was a messy event on the first filling of grease .