My left nut....

[SteveD]

Helper held the relief tool (a piece of hardwood) in place, to prevent the assembly from abutting the fork stops.

36mm BMW tool placed over the nut, and I whacked it on the side of the tool, towards the box end. Second whack caused the nut to move, and the rest was a cinch. At that point I just used the ground socket to further undo the nut. It was then a simple single hand task. I was surprised at how easy it loosened off.

[dwire]

Hooray! (Take notice-shortest post on file...)

[Duane Ausherman]

It has been interesting to follow this thread.

I well know that it is so tempting to want to get something done.................... and try to cheat a bit in order to save some time. After all, it can't really be that hard to do as Duane makes it out to be.

What you read on my website is the result of hundreds of fork alignments. Does anybody really think that I want to be mean by making the whole process harder than it really is?

Many people have written in over the years about how they didn't have the right tool to measure it exactly, so they decided it just wasn't really that necessary.

They all found out that it is that critical. Do it right the first time and be way ahead of the curve.

I just love it when someone with a lot of dirt bike experience in the teen years knows that all one has to do it bang that twisted front end against a tree and then go back to riding.

[dwire]

I just love it when someone with a lot of dirt bike experience in the teen years knows that all one has to do it bang that twisted front end against a tree and then go back to riding.

Duane, I am guilty of so many mistakes in my lifetime - well one would need use scientific notation to express them. The only thing that EVER saved my butt was being a stickler for details - that always won the race whether guys in the pits would rummage around for a clipboard, put on some "crazy scientist" glasses and start talking torque angles and things they had no clue about. Fun for them perhaps at the time - and I'll admit it was frustrating for me as a young boy, oddly, they always ended up behind my winning or top podium finishing endeavors on the track...

As for running a dirt-bike into a tree and driving off; what, that is NOT the proper procedure for a dirt-bike? I know, I know you were making an analogy to our BMW's that simply cannot at all take that sort of abuse without alignment issues which then can lead to more catastrophic and dangerous failures...

While Duane and a number of other helpful folks with guiding insights have helped me through the years of my last restore and now this one just sits, what does anyone suppose aside from financial considerations makes it sit? I or someone else perhaps now already knows the right from wrong and I simply won't compromise for less. Life, limb and even overall enjoyment all hang in the balance - so it sits as a reminder of what need be done to it as well as what need be done within my life to accomplish the goal of its restoration and resurrection.

I owe Duane personally a lot of thanks for this, no matter what I or others say about him from time to time. There are (MANY) others out there that have opened their wealth of knowledge to me for the last project and while i may not recall all the names, I surely recall their selfless helpful contributions and for that I say thanks.

[ME 109]

I just love it when someone with a lot of dirt bike experience in the teen years knows that all one has to do it bang that twisted front end against a tree and then go back to riding.

Er well um, that's zackery what I did after hitting a kangaroo 700 klm's from home.
Well it wasn't exactly a normal tree, it was more of a precision tree ya know, a wooden power pole.

But we did use a normal everyday non precision tree to tie the back wheel to while three of us pulled on a strap attached to the most bent fork leg. Those fork legs are incredibly strong.

And then we got back to riding.

We talk about stiction. Man, my RS was suffering from 'stuction'

[Duane Ausherman]

ME, it is just because those forks are so strong that they need to be aligned perfectly. They are nothing like forks from the other bikes of that era.

The more rigid the fork parts, the more precisely that they must be aligned to work. Just one more reason for having the bike fastened down completely straight while hauling it in a van, trailer or truck. It is so tempting to put it in a space that is too short with the forks cramped to one side. Don't do it.

In your case, on the road with things bent, you must do something. The problem is that you can straighten the forks to look perfect and they won't budge a bit. They will still be stuck in one position.

I must say that a couple of times I have seen then visibly bent and they still compress and extend just fine through a certain portion of the travel, but not the full travel.

BMW specs say that the fork tubes must be within .004" (.1 mm) of perfect to work. We had a case of a very serious wobble and the forks were out only .006" (.15mm) and were brand new. The factory assembly was close, but still they didn't work properly. Basically, the factory didn't know what they were doing.

This is your life and isn't an area where it is OK to be "close enough" and get away with it. Our shop max error was .001" (.025mm) and that ain't much.

[dwire]

Funny, but not. I still insist the only reason I did not high side my bike one late night driving home down into the back country where a road cut through a forest was the piss poor light emanating from my headlight. I hit an animal the size of a large dog and ran right the you know what over it. While I ended up laying on the tank pretty much, if I had seen that large of thing galloping at me any sooner than my view right near the turn signal pod (too late) I'd have likely panicked and pulled my best Evil Kan-evil move and wrecked for sure; simply trying to avoid wrecking.

Strange how those things work...

[ME 109]

Those bent fork legs were discarded after making it back home.
The worst bent fork was 19mm out of alignment from where the triple tree mounts, to the end of the leg (slider not included)
The other leg was out 6mm.

I used the bent legs to straighten the triple tree, and checked for straightness with the new straight legs, repeatedly alternating between the two until the plate of glass was happy. The triple tree is also incredibly strong.

My replacement fork legs were near perfect as I was unable to fit a .05mm feeler gauge anywhere when rolling the fork legs together.

After the initial encounter with skippy, the forks were stuck. They were that way for more than 100 kilometres until we got to Mal's at Dubbo.
An application of a 3' jimmy bar to the fork brace restored travel.......

The three of us rode home through the mountains instead of taking the safe, straight, slab.
My handle bars were out of alignment to the left due to the twisted forks/triple tree.
I could not tell, other than the handle bars were off centre, that there was a problem with the front end.
I ride my bike, and feel qualified to make such a claim. I was impressed.

[dwire]

I had read all of Duane's materials years ago, before getting into doing any of the other bike. Oddly, this bike had come from a self professed expert on the /5 series of BMW's. While Duane in his writings, makes it abundantly clear this (fork geometry and stiction issues) are important - It likely helped that I too was a bit too familiar from being a manufacturing engineer working in quality, it was indeed possible "lttle-bitty" things like this could truly matter no matter how many operators or supervisors told one they were nuts (benn doing that for years!) but I had no clue how much. After doing up the other bike and getting it all down on the money (which truly is not as hard as it seems, but the biggest challenge for me then and always likely will be is torquing those "left and right nuts" on the top fork brace once you have everything situated.

I was blown away. I figured a mid 30+ year old tired bike likely would have lousy slow fork travel; stop in different places, etc. Well yeah they do when they are messed up! I found out after following procedure, when they are "right on" My God - they are every bit as good as any other precision front end you'd see today. While I am sure that statement is likely untrue to some extent, the difference IMHO simply cannot be described!

I am glad Duane has been kind enough not only to post his experience and findings online for people to evaluate - and I can only speak for myself, he has been one of the most helpful, inspiring, intellectuals around and is always willing to give a concise accurate and helpful opinion on matters that 99% of the time comes from real experience with these bikes. - I know I would have failed in so many ways on the first bike I rebuilt had it not been for his selfless attitude about helping to steer me in the right direction, so thanks Duane I owe you a lot and that was the bike I went and had to get licensed on and nearly was killed twice in a 20 mile journey; if any of the metrics people think sometimes are far too obsessed over had not been set up and carried out in the manner they were, I might not be here to annoy the cr@p out of everyone today.

[dwire]

I don't mention that stuff so Duane gets a big head (as if he would) nor that anyone pay any attention to what he has to say. What I CAN TELL you is while I am a drum brake expert, as far as specific BMW motorcycle unique work, I had 0.0% first hand knowledge. Rebuilt those dirt bikes Duane mentioned as a kid growing up; that was it. But, when you are put into a situation on super-slab where everyone is traveling at 75MPH and a giant pile up occurs in front of you while you're still accelerating to get onto the highway and see in front of you the rear brakes of a semi trailer locked up and now every escape route is piled up with wrecked cars, you'd best bet your machine is going to work as intended.

I can say that after locking the rear wheel and laying down on the tank to the point that the brim of my helmet was touching the front fender in order to not hit this pile up - with traffic behind me all locked up trying to keep from squashing me between this semi and everyone else that was taken by surprise by the ordeal, I was most pleased everything was up to snuff. When I slid back up onto the seat, leaned up and put my feet down after the bike was at rest only about one foot from this semi, I turned around to watch the chaos behind me - this was when I realized that might be my last ride. The lady behind me stopped with six inches of clearance between her front bumper and my rear fender.

That day I was happy to have forks that did not bottom out, jack me around or stick. Brakes that worked and a bike not under threshold braking, but a downright panic stop all do their job to the maximum of their ability. We cannot turn back the hands of time to know what might have happened, but considering the 18" that separated life and death there, I think the possibilities become pretty clear as to what "could have happened."

I don't wish to accumulate many more of those type stories on my bike when I can ever get it back together again - and to that point I have people ask me why I don't just do XY and Z and start riding it - the above tail is EXACTLY WHY...