• Welcome, Guest! We hope you enjoy the excellent technical knowledge, event information and discussions that the BMW MOA forum provides. Some forum content will be hidden from you if you remain logged out. If you want to view all content, please click the 'Log in' button above and enter your BMW MOA username and password.

    If you are not an MOA member, why not take the time to join the club, so you can enjoy posting on the forum, the BMW Owners News magazine, and all of the discounts and benefits the BMW MOA offers?

  • Beginning April 1st, and running through April 30th, there is a new 2024 BMW MOA Election discussion area within The Club section of the forum. Within this forum area is also a sticky post that provides the ground rules for participating in the Election forum area. Also, the candidates statements are provided. Please read before joining the conversation, because the rules are very specific to maintain civility.

    The Election forum is here: Election Forum

Earles Fork frustrations

D

Dewayne

Guest
Hello All,

I recently sold my beloved R69US and bought a 68 R60 with an Earles Fork. I'm not familiar with these frontends and need feedback as to what my problem is..
I had a bad case of 'tank slap' (Very scary) not long after I got the bike and replaced the steering head bearings with updated tapered roller bearings. But the bike felt like it was riding on marbles, so I loosened up on the bearings and now it has a different feel... It doesn't want to lean into a turn and it feels like the front wheel is 'tuked' under the bars a bit too far.
Is it possible to get the forks out of alignment on an Earles frontend? Visibly, I don't see how... but that is what it feels like.

Any suggestions?

Thanks, Dewayne
 
for info I would

check out duane aushermans website

join the yahoo /2 group

and post on the boxerworks.com /2 forum

hope that helps
 
Other than the forks being bent, it's difficult to get them out of align AFAIK. Give it a close visual and see if you seen anything.

You might need to first try greasing the bearings. My '69 has a grease fitting on the back portion of the horizontal member of the fork. It'll take a special rubber tipped fitting to seal...supposedly some chainsaws have such a grease gun adapter. I found a steel fitting, something like you might use to fill a basketball or football with air. It's conical shaped at the end. If I hold it tightly onto the small ball of the fitting, I can get grease pushed through.

The problem will be that the grease will run to one side but not get to the other. I believe Duane's site talks about using some rope or such to hold the grease in the bearings on the close side while the rest of the grease is pumped across to the otherside. That worked for me.

Beyond that, you might have to remove the bearings for servicing. I've heard they can be a bear to get out. Again, Duane discusses that.

As for the setup of the steering bearings, I too replaced the old ball bearings with tapered roller bearings. I tightened the bearings such that when I move the handlebars off center, the front forks kind of settle gently to the stop. They shouldn't bounce of the stop...too loose. And they're too tight if you move the bars off the stop and they stay where you move them.

Another possibility is that the forks are set up for sidecar use. Actually, this might be what your problem is. There are sets of holes on the forks that you must use for solo use. Sidecar use tends to reduce the rake (make it steeper) and it's a bear to ride solo in this setting. Take a look at Duane's site

http://w6rec.com/duane/bmw/index.htm

He's got a mid '60s owners manual on-line. On page 127 of that manual, it says "For sidecar operation, the front wheel swinging arm pivot bearing is transferred from the rear position to the front position in the fork, which results in a smaller trail angle and hence is easier steering."

Check that out for sure...
 
I'm moving this discussion to the vintage forum, where I think it will get more attention from the people who know these machines.
 
Per Kurt, above: first thing is to make sure the Earle's fork is set for solo: the cross brace goes into the aft-most position. The bearings in there should be well-greased, they are not under a lot of stress, so they last forever, but they may be stiff?

Does the front end compress easily? Mine has amazingly smooth ride, has a very light steering feel (you DO have the lovely chrome steering damper set at virtually no resistance, I hope...?). I am amazed at how "nimble" the front end feels when I want to do some swervies.....
 
Did you check swing arm berings?
What was your speed when having Tankslapper?
Are you using damper?

I also notice that with a modern tyre you get a lot of movement because the sidewalls are weaker than the tyres from the 60s and 70s. I have simular wobble only at low speed (parking lot/driveway speeds) but did not have with old tyres (my /2 had a rear only fittment on the front, weather rotted but no wobble until newer front only tyre was installed) On mine you can shake handlebars sitting still and see movement in sidewall give. Handles great over 10 MPH up to top speed.
 
Well, I think I might need to loosen the steering head a bit more... I haven't greased the pivot bearings due to not knowing how... but will work on that. The front pivot is in the rear position, so that's not it.

I just pulled the rear wheel off to replace the tire and found that the splines on the final drive are in real bad shape. Is it easier to find a good used unit or have this one rebuilt?

Thanks for all your responses!

Dewayne
 
By the way, I'm not using the damper.. it's non functional.

And I had the tank slapper on the expressway going 65mph... not fun... it didn't stop until I managed to get the bike down to a crawl. Believe me, you don't ever wnat to go through that experience.. !

Dewayne
 
I just pulled the rear wheel off to replace the tire and found that the splines on the final drive are in real bad shape. Is it easier to find a good used unit or have this one rebuilt?

I've not really looked for final drives, but I believe they show up from time to time. If you were to look at getting it repaired, Hansen's in Oregon is the way to go, especially for the /5 on bikes. You could see what they could do for a /2:

http://www.hansensmc.com/

By the way, I'm not using the damper.. it's non functional.

The hydraulic damper is non-functional on my R69S but I don't have any real problems with looseness. I do have a Wixom handlebar fairing which might contributed to "weirdness" in handling if I'm in really buffeting crosswinds. You shouldn't need to rely on a damper to solve this problem. But if you want to replace your damper, Vech in Mississippi can help you out.

http://members.aol.com/vechbmw/index.html

If you continue to have problems you might want to give him a call...if you haven't contacted him yet. He's more than willing to talk you through things on the phone...and then some!! He definitely knows /2 machines...

BTW...what part of the country are you in? Maybe there's some shop that's near you that can provide some assistance.
 
Thanks for the responses... I've called Vech in the past, and you're right, he is always more than willing to help. I just hate to bug him too often. Besides, half the fun is tearing into your bike and finding out what kind of condition it is really in.. :D

I live in Tulsa OK and our dealership closed last year. We have a local BMW club and I know a couple of people in it... may have to call them tonight.

Anyway... Thanks again,

Dewayne
 
Well, I think I might need to loosen the steering head a bit more... I haven't greased the pivot bearings due to not knowing how... but will work on that. The front pivot is in the rear position, so that's not it.

Dewayne

I would be VERY careful about loosening the steering head... it may be TOO LOOSE. What you want is absolutely NO PLAY. I found that when I put a load on it, it was too loose, in spite of having felt perfect while it was on the stand. You may have to tighten it down enough to seat the bearings (light press fit) and then back off enough so you dont feel any notchiness.

Try this: put a couple of pieces of slippery-something (wax paper?) between two pieces of plywood. Then roll the front wheel onto the plywood, and try to turn it. First, turn with the bars, then go up front and move the wheel back and forth with your hands. You should feel no clicking, jerking, etc, from side to side. You said you had new head bearings, so there should not be any worn spots.... I am guessing that you have the bearings too loose.

Regarding grease on the fork tube: probably not critical to steering so much as bump-absorption..... when you roll forward and slam on the front brake, does the suspension operate, etc. I can hear my springs "groan" as the front end works it's "up" magic!
 
Thanks bpeckm for your response..

I suspect the bearings to be a little tight still because when I turn the bars slightly off center without weight on the front, they stay in place, not dropping off to the side at all.

As far as I can tell the front suspension is working fine.. up and down. I'm going to replace the front tire tomorrow ( it is like new but is around 8 yrs old ) and see if that helps too...

Dewayne
 
If you strike out finding any problems with the front of the bike, take a very close look at the rear - swing arm bearings, wheel bearings, spokes, tire.

Recalling old flat tracking days -- if the front was misbehaving, the problem was generally in the rear. Fine tuning of the rear would have a huge impact on the behavior of the front of the bike.

Motard
 
Ok.. Thanks Motard... I'm getting a new rear tire tomorrow also and I'm replacing the bearings tonite... they weren't that bad...

How do I check the rear swing arm??

Dewayne
 
Getting a good feel on movement of the rear swing arm is hampered because of the rear shock attachment. You can disconnect the lower ends freeing up the swing arm but the shocks will still block full up and down movement of the arm. This quick check might turn up reason for further disassembly.
One point which you can verify once the shocks are loose -- make sure the damping action on both shocks is close to equal. A non-functioning shock can put an asymmetrical load on the swing arm. A bump or ripple in the road surface will induce a twisting moment on the swing arm - not good.
Bye the way, also disconnect the front shocks and check for this fault.
Good luck

Motard

PS - forgot to say that shocks must be taken apart, relieving spring tension, to check them -- you can do this, might have to get a book for guidance. I've done it many times without the prescribed special tooling, does take four hands though.
 
Last edited:
Ok.. thanks guys. You've given me a place or two to start...

Much appreciated,
Dewayne
 
By the way, not to make a pest of myself, but since I don't have a manual, which way do you set the rear shocks for solo vs double?

Thanks, Dewayne
 
Another "check" point: make sure that the axle nuts on the right side are to spec. They are THE key to keeping the bearing stacks at the correct pre-load (side pressure).

The wheel bearings are an idiosyncrasy of the BMW's, pre '81. Basically, the axle is pulled through the hub of the wheel, (which contains the bearings) towards the right by that big nut: the shoulder on the axle (or the long reducing bushing on the front) goes against the left outside of the bearing stack and is pulled against the right fork by that big nut. Torque is NOT very high, 20-something pounds if I remember, but if it is too loose, or if the bearings are incorrectly installed, there could be some slop in the bearings.

To check for play: loosen the big right nut, loosen the pinch bolt. At this point you should be able to take your axle removal pin, stick it into the left hole in the axle, and turn the axle and pull it out towards the left. As long as you can twist and pull it reasonably easily, that is OK, you are just checking to make sure that it is not being held somewhere before you "preload" the bearing stack. Then tighten the big right nut to the 20-something torque figure. If you have the toolkit wrench for that size nut, you can tighten it hard with that, on the theory that you can produce 20-something torque and not much more with that short little wrench and your tender hands..... Then, with the weight off the front (weigh down the back or have someone hold the back down), see if there is any lateral play. There should be none. Zero. If there is any slack, clicking, etc, you best look into those bearings. Then snug the pinchbolt just to make sure that nothing can come adrift. But the entire wheel bearing assembly is dependent on that big right nut. See Duane Ausherman for more than you would ever want to know:

http://w6rec.com/duane/bmw/wheel_bearing/index.htm

Also, don't discount the new tire: old tires can be a bear! I had an older Conti with traditional straight ribbing, which would give me the willies on grooved concrete or steel-grate bridges. I put on a modern-looking treaded Dunlop, and presto, entirely new feel.

So, do the tires, check the wheel bearings for play.

Rear swingarm could be slack, as mentioned above. That is easy to check, as well. Just grab the swingarm on either side and push/pull laterally while the bike is on centerstand. There should be no play there, either. A friend has a /5, and we were checking over the bikes, and I checked the swingarm and found 1/4" play: he said it rode fine! Needless to say, we snugged it up.....
 
By the way, not to make a pest of myself, but since I don't have a manual, which way do you set the rear shocks for solo vs double?

Thanks, Dewayne

Tighter is for two-up... but you can do it whatever way you feel the most comfortable. I am light, so I use the soft setting.
 
Back
Top