The New And Improved Unofficial R65 Forum V2

Technical Discussion => BMW Technical Q&A, Primarily R65 => Topic started by: Barry on September 23, 2009, 03:17:44 PM

Title: When to replace fork seals
Post by: Barry on September 23, 2009, 03:17:44 PM
Do you think fork seals should be replaced at the first  sign of a slight tide mark of oil on one stanchion ?

I'm thinking it could be quite a while before they leak badly and I'm reluctant to rush into it because last time I had the forks apart I manged by shear skill or maybe it was luck (well it certainly wasn't the glass plate method) to achieve a really good alignment and I don't want to spoil it.
Title: Re: When to replace fork seals
Post by: beemer on September 23, 2009, 03:46:51 PM
I would leave it till it get's worse,it won't fail the MOT unless they are really weeping,mine didn't anyway,but i have since replaced it.
Title: Re: When to replace fork seals
Post by: montmil on September 23, 2009, 05:48:36 PM
You may have to keep a closer weather eye on the fork oil levels; keeping them equal volume.

Monte
Title: Re: When to replace fork seals
Post by: Bob_Roller on September 23, 2009, 07:17:28 PM
Put a set of gaiters on , and no one will know the difference .
Title: Re: When to replace fork seals
Post by: Rob Valdez 79 R65 on September 23, 2009, 08:40:16 PM
Well, the gaiters will let the new pair of seals last longer, if you dropped the fork legs and replaced the seals.

One of the nice things about the twin-shock R65's is that they have full triple clamps both top and bottom on the fork assembly, rather than the flat steel plate that the type-247's have.  (Including the mono-shock R65s!).  This eliminates a lot of the fork alignment issues.
Title: Re: When to replace fork seals
Post by: steve_wicks on September 24, 2009, 02:06:34 AM
I replaced my seals as the forks had gone soft even though the oil marks on the stanchions didn't look too bad.
 
But the seals didn't last as the stanchions were pitted so now everthing is apart and I'm waiting for them to comeback from being rechromed.
 
I bought a pair of bright red gaiters to go with my bright red '81 R65 I call 'mutti'
Title: Re: When to replace fork seals
Post by: montmil on September 24, 2009, 05:40:12 AM
And a quick BTW regarding fork seal replacement and the concern on alignment...

It's not necessary to remove the forks legs from the "tree" during seal replacement. With the large aluminum fork legs fittings and the lowers off, there's not an issue with alignment.   Monte
Title: Re: When to replace fork seals
Post by: Barry on September 24, 2009, 06:50:00 AM
Thanks guys

I think I'll leave the seals alone until they get worse and then maybe fit some gaiters.

I've had a few goes at fork alignment including trying to measure everything to the nearest thou and the way that worked best for me was to assemble the forks without springs then assemble and torque up everything in stages with the forks compressed to the top of their travel checking at each stage the forks were still free to slide. The very last thing to do was replace the springs.  This gave me a very significant improvement in fork compliance so much so I had to put in thicker oil. Previously my damping was a combination of 5W oil and some stiction. Now with the stiction gone I was getting some floating of the front end until I put in 7.5W  The bike now handles better that it’s ever done which is why I’m reluctant to disturb anything.

    
Title: Re: When to replace fork seals
Post by: Rob Valdez 79 R65 on September 24, 2009, 05:23:46 PM
7.5W oil is standard.
Title: Re: When to replace fork seals
Post by: steve_wicks on September 25, 2009, 01:08:18 PM
I got 'mutti' back today ...... what a difference. Feels soooo much better but front brakes are only a slight improvement.

I have done everything I can to the brakes so now its time to to either shoot 'mutti' and put her out of her misery or try find an alternative front end which will annoy me after spending all the money on calliper rebuild, new hose, pads, re-chroming stanchions, new front tyre

But I really have no confidence in the brakes as they are downright dangerous.  Riding it is not fun as I'm forever trying to ride slower than I need to. >:(
Title: Re: When to replace fork seals
Post by: Rob Valdez 79 R65 on September 25, 2009, 01:46:49 PM
Quote
I got 'mutti' back today ...... what a difference. Feels soooo much better but front brakes are only a slight improvement.

I have done everything I can to the brakes so now its time to to either shoot 'mutti' and put her out of her misery or try find an alternative front end which will annoy me after spending all the money on calliper rebuild, new hose, pads, re-chroming stanchions, new front tyre

But I really have no confidence in the brakes as they are downright dangerous.  Riding it is not fun as I'm forever trying to ride slower than I need to. >:(


What kind of a motorcycle were you riding before?  These brakes are no comparison to "modern" brakes, but I've never found my single disk lacking for getting me stopped.
Title: Re: When to replace fork seals
Post by: Bob_Roller on September 25, 2009, 02:12:28 PM
Quote
I got 'mutti' back today ...... what a difference. Feels soooo much better but front brakes are only a slight improvement.

I have done everything I can to the brakes so now its time to to either shoot 'mutti' and put her out of her misery or try find an alternative front end which will annoy me after spending all the money on calliper rebuild, new hose, pads, re-chroming stanchions, new front tyre

But I really have no confidence in the brakes as they are downright dangerous.  Riding it is not fun as I'm forever trying to ride slower than I need to. >:(

Has any maintenance been done to the master cylinder ?
Title: Re: When to replace fork seals
Post by: steve_wicks on September 26, 2009, 02:02:05 AM
Master cylinder hasn't been touched as the lever holds it's position and isn't squishy. It just feels like there's no power in the brakes. Two finges on the lever hardly make a dent in speed. It needs a big muscular squeeze.

Latest person to look at it said all old BMWs are like that.

I've been riding a Kawasaki ER6F and Honda XR 200 and that has made me realise how bad BMW brakes really are.

The brakes are really so bad that I was going to use it today but decided not to because If I need to stop quickly I've got myself a biiiig problem.

I like the R65 and bought it as a workhorse but I've spent so much money on it and its still not right, so do I cut my losses and sell it or carry on pouring money into a bottomless pit called BMW.

Paid R12 000 spent R18 000 (about $2 500) ..... could have bought a clean late '90s F650 for that kind of money.

Title: Re: When to replace fork seals
Post by: Bob_Roller on September 26, 2009, 08:12:28 AM
Do you have a single, or dual front disc brake system ?
Title: Re: When to replace fork seals
Post by: steve_wicks on September 26, 2009, 02:54:37 PM
It's a single disc. Std disc, nor is it worn enough to warrant replacement.

I've been searching for info on BM R65, but still haven't found out why the brakes are so bad.

Surely there must be another wheel, forks, rotor & caliper set-up that will bolt straight on.
Title: Re: When to replace fork seals
Post by: Bob_Roller on September 26, 2009, 03:26:38 PM
I was just wondering, if someone had done a dual disc modification, and was still using the 12 mm master cylinder .
Title: Re: When to replace fork seals
Post by: Rob Valdez 79 R65 on September 26, 2009, 03:52:03 PM
Quote
I've been riding a Kawasaki ER6F and Honda XR 200 and that has made me realise how bad BMW brakes really are.


That would explain a lot.  They both have excellent brakes, I am sure, and the XR200 is so light, it wouldn't take much to stop it, anyway.

I am afraid you are dealing with a situation that cannot be resolved easily or cheaply.  I'm thinking aftermarket, multi-piston calipers, here.

And rebuild that master cylinder!  The job isn't done if it's only half-done!
Title: Re: When to replace fork seals
Post by: drewboid on September 29, 2009, 10:13:23 AM
Repeating what I have said in other posts concerning the front brakes:
My fiance had problems stopping her R65 due to small hands and a lack of hand strength. Adding the second front disk was the answer - now the bike stops great! SS brake lines and originally we used the 12mm MC. I could get the lever back to the grip but she could not.

Since then we have changed to the 14mm MC and now I can't pull the lever all the way back - she did not notice any great difference in braking.  For me the second disk is the way to go and I have been buying the parts to add the second disk to my R75/6.  YMMV
Title: Re: When to replace fork seals
Post by: steve_wicks on September 29, 2009, 11:04:19 AM
Oh ....... about this thread.

My bike feels like a modern sports bike now that the forks have been done. It is also stable under braking and doesn't start wobbling when going through a nice sweeping corner not far from home.

If the seals are worn & leaky, your handling will be nowhere near what it should be and it really makes a huge difference.

Now, all I need to do is get it to stop ................ :'(