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Old 01-18-2013, 07:46 AM   #16
craydds
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Quote:
Originally Posted by 240sx4u View Post
I understand they do improve rigidity but do they make the forks basically idiot proof to align?
My experience is that the forks are impossible to align WITHOUT a precisely machined triple. I installed the ToasterTan and it made the fork alignment procedures (Randy Glass) fast and easy. This was addressed in a rambling fashion in posts following #32, #51, and #100 - http://www.advrider.com/forums/showt...=741179&page=3 . In essence, the stock upper plate (or a poorly machine triple) does not match the lower triple and thereby CAUSES the forks to be misaligned; one must have matching upper and lower clamps to get the forks parallel. While Supershaft and myself may argue back and forth about the merits of the Randy Glass method, I think we are both trying to get the best possible fork alignment, even though we have different approaches.
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Old 01-18-2013, 07:51 AM   #17
craydds
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Originally Posted by Renner View Post
No. In fact they can introduce error.
I'm currently installing an SJ brace on a friend's /7. The center to center distance in the yoke bores for the tubes is slightly wider than that of the brace. Installing the brace causes the forks to splay outward. I'm placing .002 shims at the inboard radius where the brace captures the tubes in order to meet parallelism.

Best to true the yoke and tubes per Randy Glass' article then check again with the brace installed.

I like both TT and SJ braces and believe they're a well-worth the money but they're no cure-all.
This was precisely my experience with the SJ clamp, that it did not match the lower and CAUSED misalignment of the forks. I installed the TT and found that it facilitated aligning the forks in parallel.
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Old 01-18-2013, 10:58 AM   #18
chasbmw
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I like the Telefix fork brace, it works well on my R90/6, it does need to be installed carefully and checked as you go to ensure that you don't build in stiction, just make sure that the parts that clamp onto the forks are gently tightened.
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Old 01-18-2013, 11:32 AM   #19
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Setting up forks can be a matter of luck sometimes. Sometimes it all just falls into place. I just installed a SJ top tree on my own bike and was a bit concerned at first. The top tree pulled my tube toe in quite a bit. Like I always advise, I simply tightened and re-loosened the setup until I found a method that got it all tight and straight at the same time. My particular setup required tightening the top pinch bolt a bit, then the bottom pinch bolt a bit, then back up to the top and so on. With my magnetic V block on a tube I could watch that plane of movement the whole time as I tightened down one side with the other side already being fully torqued. I found a sequence that got it all together straight. The for and aft plane was hardly effected the whole time. How much and when you torque the pinch bolts and all the rest of the fasteners involved effects all setups and this is the method that the Glass article largely over looks IMO and then resorts to all sorts of stuff that is largely what I would call crash repair, not aligning forks.

I think the after market top trees set up right do help. Same story with the aftermarket fork braces. I prefer the tube type. I really prefer the stock ones on Monolevers but that is just one of the reasons I ride a Mono. Same story with Mono axles. I do think it helps modifying the earlier front axles to slide further into the sliders as well but it is tricky machining the axle right there. It's right were the bearing is!

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Old 01-18-2013, 11:58 AM   #20
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We have been making upper clamps for airhead BMWs since 1979, yea - a long time. They fit correct and all the stock parts work. (ins. mounts etc.) We send them all over the world and have NO problems with fit. They are a proven part that works very well.

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Old 01-18-2013, 12:17 PM   #21
craydds
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Originally Posted by supershaft View Post
How much and when you torque the pinch bolts and all the rest of the fasteners involved effects all setups and this is the method that the Glass article largely over looks...
Sounds like you had good results with your SJ triple. I will try my SJ brace on one of my other bikes and play with it until I get it right, if possible. For my R90S with the TT triple, it was a simple bolt on an go installation (yes, I did use the plate glass and a dial indicator); now, my fork tubes are parallel in both planes. I do like the Glass method of assembling the lower sliders/axle/fender brace, it really makes it all fit together very well. I like the tube fender brace as well. If a fender brace is tweaked in any fashion, then it will mess up all your fork alignment efforts. The Glass lower slider assembly process will reveal any fault with the fender brace and one can attempt to correct it. I have the SJ tube fender brace and it was straight and dimensionally correct, allowing very good alignment of the lowers. In summary, when the fork tubes are PARALLEL in both planes, and the lower sliders are assembled correctly, it all should work together very well.
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Old 01-18-2013, 01:30 PM   #22
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Does anyone actually check the lower t/c? I have found several over the years that wouldn't hold the legs parallel and had to be straightened before the top clamp could be fitted properly. No sign of crash damage.
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Old 01-18-2013, 02:25 PM   #23
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Originally Posted by robtg View Post
Does anyone actually check the lower t/c? I have found several over the years that wouldn't hold the legs parallel and had to be straightened before the top clamp could be fitted properly. No sign of crash damage.
I believe that is the purpose of the Randy Glass method. First, one checks the fork tubes for alignment, clamped only by the lower triple. If out of parallel (in two planes) one may attempt (and herein lies the rub) to tweak the lower triple and thereby align the fork tubes. Then proceed to install the upper clamp, maintaining the alignment, etc., and on to the lower sliders. Supershaft loves this method.
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Old 01-18-2013, 02:37 PM   #24
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Originally Posted by craydds View Post
I believe that is the purpose of the Randy Glass method. First, one checks the fork tubes for alignment, clamped only by the lower triple. If out of parallel (in two planes) one may attempt (and herein lies the rub) to tweak the lower triple and thereby align the fork tubes. Then proceed to install the upper clamp, maintaining the alignment, etc., and on to the lower sliders. Supershaft loves this method.

I heard of the Randy Glass method but didn't check it out. Just straightened them out made them work.
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Old 01-18-2013, 02:50 PM   #25
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Originally Posted by robtg View Post
I heard of the Randy Glass method but didn't check it out. Just straightened them out made them work.
Good job! Here is one link - http://w6rec.com/duane/bmw/fork/title.html ; if that doesn't take you to the article, I have another link.
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Old 01-18-2013, 04:16 PM   #26
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I check lower trees. Yes some of them are bowed just like the upper plates get. I am like robtg. I just straighten them (actually, I have just got new ones but they can be straightened in a press) and go from there. The Glass method has almost nothing to do with a 'real' top tree with pinch bolts IMO. How could it? ANY perfectly machined set of trees can pull the tubes this way or that as they are tightened down if you aren't lucky IMO. It's a fact that the trees move as the pinch pinches. How else do they get tight? That movement can move the tubes. There are some good points in the Glass article but overall I think it makes the whole process about ten more times complicated than it really is. But some people like that.
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Old 01-18-2013, 05:27 PM   #27
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Originally Posted by supershaft View Post
There are some good points in the Glass article but overall I think it makes the whole process about ten more times complicated than it really is.
My brother laughs at me because of the steps I go through to align my forks. He has late model sport bikes with precision/massive upper and lower trees; one simply tightens up the clamps (yes, there is a tightening sequence) and the forks are in perfect alignment. As with any technique (Glass) for any procedure (carb balancing), we take the good points, modify some steps, and make it work in our own hands. I do not follow Randy's procedures to the letter, either. But, it is a good educational article to help the uninitiated to start to think about correct fork alignment.
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