Miles By Motorcycle
established 11 years ago
R1100S SitrepSubscribe to this blog RSS Feed
    You must be logged in and belong to this group to post to this forum.
    1 of 22
    Yermo
    11 years ago
    So I took the front end of the R1100S apart and installed the replacement forks I got. I have to admit I'm very impressed with the seller:



    The forks were professionally packaged up and are very clean.

    I went through the mounting/aligning procedure carefully but I'm sad to report it looks like No Joy.

    I've looked at it from every angle and I simply don't understand what's bent. I've looked at the trailing arm which we initially thought might be bent. I've look at the triple clamps. I've looked at the top frame.

    Disgusted I've left it partially assembled. I'll look at it again with fresh eyes tomorrow. Worst case I'll bolt it back together and take it up to Bob's on Saturday. Maybe they can tell me what's bent.
    2 of 22
    Ian
    11 years ago
    Now that you've got the original forks off, do they appear as straight as the replacements?

    In what way (or where) is it not right?

    Bummer!
    3 of 22
    Yermo
    11 years ago
    The handle bars are skewed to the right. i.e. when the wheel points straight the handle bars are turned to the right.

    If I loosen everything up and "force" the bars straight using the old school grab the wheel with your legs and twist the bars, then the front wheel doesn't spin freely.

    Both the upper and lower triple clamps are free floating. So the only thing that should dictate whether or not they are aligned is the tube that goes through them.

    I thought the old forks were straight but figuring they were the only thing that could explain the skew, I got a pair of known straight ones. These are in a really good shape.

    So I'm really not sure what's causing the skew.
    4 of 22
    John St John
    11 years ago
    The one sure way to find out what's going on with your bike: take it to a G.M.D. Computrack center. I took my white K100 to a place in the Boston Area and found the service to be very valuable. I learned a lot that day.
    Link #4844
    John St John
    11 years ago

    G.M.D. Computrack NorthEast

    Read by more often by those pesky Cycle News editors than all the baseball sites on the net

    http://www.computrackboston.com/
    5 of 22
    Yermo
    11 years ago
    oh cool. Thanks for the pointer!
    6 of 22
    jpcfjr
    11 years ago
    Have you checked the wheel bearings to see if they are squarely seated in the hub and/or otherwise damaged?
    7 of 22
    Yermo
    11 years ago
    It's obviously crooked with the axle in but the wheel off. It's something between the lower and upper triple clamp, I"m guessing, but I'm not sure.
    8 of 22
    John St John
    11 years ago
    There's some rather nice riding, just north of Boston. Just saying........
    9 of 22
    Yermo
    11 years ago
    10 of 22
    John St John
    11 years ago
    I noticed that Peter's (Computrack) web site could use some help. The Forum and race results pages are DNF. Perhaps a barter would be mutually beneficial?

    BTW: Peter is a great guy, with loads of riding and racing experience. He would be a valuable addition to any riders circle of acquaintances. (Think Jason Statham in a motorcycle movie. Now, you've got the picture
    11 of 22
    Yun Lung Yang
    11 years ago
    So he needs to juice up constantly to stay alive right? Hahaha
    12 of 22
    Yermo
    11 years ago
    I bought a couple of flat rulers and placed them on the lower triple clamp in an attempt to see if it's straight.

    I /think/ it shows the lower trip clamp is twisted but I'm going to look at it again. I really need two steel straight edges to be sure.
    13 of 22
    buffalo
    11 years ago
    Does Bob's have a frame measuring jig?
    14 of 22
    Yermo
    11 years ago
    I don't think so.

    I've looked at the lower triple clamp again with Yun. At this point I'm pretty sure the clamp is slightly bent backwards on the right side (as sitting on the bike) which corresponds with the bars being angled to the right.

    I've been feeling pretty poorly (super low energy) for quite some weeks now so progress has been very slow. I hope to take the triple clamp off tomorrow sometime and take a closer look at with on a flat surface before ordering a replacement.

    At this point I think it's the only thing that could be bent that would explain what I'm seeing. As Josh pointed out on the phone, given the distance between the lower triple clamp and the upper one, a very small bend in the lower clamp would have an over sized effect on the upper end.
    15 of 22
    jpcfjr
    11 years ago
    http://www.ebay.com/itm/BMW-R1100S-R-1100-S-1999-Lower-...

    ...and it's even from a '99.

    Edit: This got me thinking, could one build an entire r1100s cost effectively from ebay parts? Well, here's a nice engine for $850. I think it could be done for a reasonable price as long as you don't count your time.
    16 of 22
    Yermo
    11 years ago
    So I'm finally feeling just a little bit better and managed to muster up enough energy to pull the forks off. Just as I was getting around to pulling off the lower triple clamp Josh arrived for s surprise visit.

    This was a good thing since removing the triple clamp is much easier with two people.

    Even with the thing off the bike it was really hard to tell whether or not it was really bent. From some angles it looked bent but from others it seemed straight.

    We went into the living room and put the thing on the coffee table, a flat glass surface which I assume is reasonably straight. Pressing one side down such that it's flush with the table around the circumference of the mount point you can see the other side is tilted upwards.

    It's bent.

    17 of 22
    Yermo
    11 years ago
    Replacement lower triple clamp purchased for $159. It should be here on the 21st.
    18 of 22
    Ian
    11 years ago
    So did the triple clamp get bent without bending the forks? Or do you think the original forks actually WERE bent? After getting the replacements you seemed to think that they were not bent.
    19 of 22
    Yermo
    11 years ago
    It's really difficult for me to tell whether the forks are bent.

    The upper tubes do have a bend in them of a few millimeters which I was able to confirm but determining how straight the lower parts are since they are irregularly shaped is proving difficult.

    Also, I was concerned about the internals of the forks. Even if they were not bent beyond serviceable limits I think it was probably prudent to replace them. The new forks I got are MUCH cleaner.

    Things "seemed" significantly less crooked after I bolted on the new forks so I do suspect the old fork were contributing to the skewed handle bar angle.
    20 of 22
    Yun Lung Yang
    11 years ago
    Congrats on identifying the dmg
    21 of 22
    Yermo
    11 years ago
    I should have known better than to leave it on the jack like that.

    The jack gave way, the center stand folded under and the bike, which had the front wheel, forks, triple clamp and rear wheel fell over hard.

    I found it the next morning, gasoline all over the floor.

    Very sad.

    Once I can get it up on the center stand and start bolting things back on i'll have a better idea about damage.

    It has just not been my day. Stupid error and completely my own fault.
    22 of 22
    Yun Lung Yang
    11 years ago