Any of you guys done the full alignment on airhead forks?

Discussion in 'Airheads' started by 240sx4u, Mar 27, 2011.

  1. 240sx4u

    240sx4u Been here awhile

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    I know I haven't posted a thing since last year. I got the bike mostly done and lost motivation since it was getting cold and I didn't want to register it right before winter. The final step that was needed was for me to do a proper fork alignment. I am finally getting around to this now.

    Have any of you guys used this; http://w6rec.com/duane/bmw/fork/chapter6.html

    I have 1/16" glass and the tapping thing works, but I am finding that depending on how I hold the glass I can manipulate which corners "click". It is also possible my forks are darn near straight and all my worry is for no reason.

    Thoughts? This is ultra tedious and don't want to do it twice. I am really hoping to be riding this bike this summer.

    Thanks guys, happy to be back in action!

    Evan:clap
    #1
  2. jtwind

    jtwind Wisconsin Airhead

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    Evan, Use plate glass it's flat! 1/16" thick stuff isn't and it will give alittle on top of it. I use 1/4" or 3/8" plate.
    #2
  3. 240sx4u

    240sx4u Been here awhile

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    Crap, I wish I had known there was a difference when I got this glass. I have two pieces of 1/16" glass for no reason now! lol


    Hope all is well Jeff!

    Evan
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  4. supershaft

    supershaft because I can

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    I am guessing you mean a full alignment per that article? If that's what you mean, no. I have aligned a lot of forks and have never found the need to do half of what that article suggests but I don't straighten bent front end components, I replace them with new. It's hard enough to get them set up when everything is straight!
    #4
  5. 240sx4u

    240sx4u Been here awhile

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    Mine are straight as far as I can tell at least. I will be doing it per the article, I don't have the experience to know if it's good enough without going into a tank slapper at 60mph! lol

    It is good to know that if I don't get it flawless per the article, odds are it will work fine.

    Evan
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  6. jtwind

    jtwind Wisconsin Airhead

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    In a pinch I've used the bottom of one of my woodworking jack planes. I have some that I've lapped the bottom and they are very flat. They are also long and 3-4 inches wide so work perfectly.

    I'm doing good Evan. PM me your phone number some time. I'm building a dirt bike out of a /5 and wanted to pick your brain on welding up exhausts. I remember that stainless one on your Nissan.

    Most of the fork alignment stuff is commom sense, with the springs out and no tire on just see if the move easily up and down. You want very little resistance, smooth, no sticky spots etc. If they dont' move easily it's time to figure out if something is bent, or they are out of plane, or angle in or out from each other etc. It's almost always worth checking them and getting them aligned.
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  7. 240sx4u

    240sx4u Been here awhile

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    The exhaust on my /5 is semi-custom. I used triumph mufflers but had to extend everything to fit and weld mounting tabs to them. PM on the way. I generally use mild steel, but can do stainless if I get the appropriate wire.

    Thanks for the reminder to call the glass shop! lol

    Evan
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  8. jtwind

    jtwind Wisconsin Airhead

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    Check habitat for humanities store on Cottage Grove rd. They had really inexpensive hunks of quarter inch glass last time I was in there. They'd need to be cut but were $2!!
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  9. ozmoses

    ozmoses Ride On

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    240sx4u-

    From what I've seen on the 'net, supershaft takes exception to Ausherman methodology.

    In his "defense", that methodology does hail from the /2 and particularly the /5 era...apparently there were some manufacturing/engineering issues w/ early telescopic forks.

    The truth probably lies in the middle.

    Start w/ the "stiction" test; how do they slide?

    Get yourself a smallish mirror to check fork plane, it's inexpensive & readily available.

    I don't know the history of your bike, but unless you have known issues, a severe impact for example, the full Procedure may not be necessary at all.

    Good luck.

    Edit, I see as I was typing, JTWind made a similar suggestion; IMO his info is good!
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  10. 240sx4u

    240sx4u Been here awhile

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    Great tip Jeff. Ill shoot over there on lunch today. Only problem is that I can't get out of there without going through the whole store!
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  11. 240sx4u

    240sx4u Been here awhile

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    Oz, I had the entire front end of the bike apart for bearings and a fork rebuild. Interestingly enough, in hindsight there was definitely stiction. I thought the shocks were bad because I am used to dealing with gas shocks/struts.

    I know the last owner, but beyond that who knows.

    Evan
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  12. ozmoses

    ozmoses Ride On

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    It's funny, when I purchased my first airhead the front end was sacked. Having zero knowledge or experience and armed only w/ Clymer's, I dismantled the front end, looked at the schematic vs the parts in front of me, picked up the phone & placed an order. Three days later I reversed the procedure and went for a ride-no problems.

    Afterward I found Duane's site.

    With the purchase of the next airhead, I would say my attitude toward fork alignment bordered on Obsessive-Compulsive!

    Now, if yours is apart that's a good opportunity to checks the tubes themselves for straight. Perhaps that's the cause of your stiction?
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  13. 240sx4u

    240sx4u Been here awhile

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    You make a strong argument. I am going to pull them and check for straightness. Sounds dumb, but it never occurred to me that I was dealing with stiction before I actually posted that last reply.
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  14. supershaft

    supershaft because I can

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    Actually, that article isn't by Duane, it's by Randy.

    There are parts of the article that make perfect sense and other parts that don't make much at all.

    The "Alignment tool"? A magnetic V block is made for such things and works better plus you can use both hands while using it.

    With straight components you can do everything they are doing without the block and tackle by turning and/or re-tightening components sometimes over and over. Time consuming yes but it is still a lot easier than the block and tackle. IMO, the block and tackle is almost laughable.

    You have to get the set up just so so for it to work right but there are other, easier ways of going about it than that article suggests.
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  15. 240sx4u

    240sx4u Been here awhile

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    I actually somewhat agree with Supershaft. I was able to make adjustments fast and easily by tweaking with a 2x4. I would have left them for a day to make sure they didn't creep back but I definitely didn't require block and tackle to twist everything back.

    I have a magnetic Vblock and that was what I was going to use until I dropped my dial indicator on the floor last night. Thank god it was a cheapie!

    Supershaft; you should consider putting up a diy for your method. Randy's article was so complex and detailed it actually made me put it off until now.

    Thanks for your input guys. Ill check them for straightness first.

    Evan
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  16. supershaft

    supershaft because I can

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    I think you are understanding what I am getting at.

    My DIY article would be pretty simple. Start with straight tubes and straight trees. Then turn, tighten and re-tighten somemore until it is all straight. Even slightly different torques pull things this way and that. A 2X4 might be faster but I do without that or the block and tackle. It's simple and at the same time complicted in a way if you get it down to minute details. You just have to F with it. Sometimes over and over and suddenly it wil be right.
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  17. 240sx4u

    240sx4u Been here awhile

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    I suppose I didn't need the 2x4 but it was right there and my back was sore! :rofl

    I understand what you are getting at.

    Evan
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  18. Wirespokes

    Wirespokes Beemerholics Anonymous

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    If you're into the expense of new triple trees, then go for it! Me, I'll straightne mine if they're slightly out. I believe it's possible lower triple trees have gotten tweaked due to incorrect steering head bearing adjustments, rather than accidents. After a year being tweaked, and baking in the sun on a hot afternoon, it's taken a new set.

    But if the tubes are bent, for sure take care of that first!

    Excuvator (doing this alignment) found that his new aftermarket aluminum top clamp wasn't machined properly and sent it back.

    But the idea is simple - just do what measurements are required to find out if the fork tubes are parallel and both in the same plane.

    That's all! Not a big deal really.

    But where both Excuvator and I had problems was getting the tubes parallel by blocking (or whatever means) with the idea of the lower tree relaxing into the new 'set'.

    Didn't work.

    What did, was heating the triple tree with a propane torch (while under tension to be parallel) - and that relaxed it and allowed it to take the proper set.
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  19. 240sx4u

    240sx4u Been here awhile

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    'spokes;

    That makes sense to me. When I read complicated DIY's on the internet I generally get overwhelmed in a situation where I could have figured it out myself faster.

    Heating was the most logical idea to me! I am going to pull the fork legs sometime tonight hopefully to check for straightness. Aluminum does have cold flow properties but where I am skeptical is "how long does it take to cold flow" as opposed to just bending it. 6months in a twisted configuration isn't in the cards.

    Evan
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  20. supershaft

    supershaft because I can

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    WS, how far off are you talking about?
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