GEBE axle mount- modifications and additions

Discussion in 'Rack Mounted Engines' started by bamabikeguy, Aug 12, 2007.

  1. bamabikeguy

    bamabikeguy Active Member

    Sam and I have been discussing a thread dealing with any "drilling and/or cutting" the GEBE axle mount. Last week, when I was looking into the "flipping Starr's gas tank/getting him out of that tree", clicking through GEBEs testimonials, I saw 2 "conversions to frame mount" similar to Sam's, a few hitches like Loco's, an some "saddle bag extentions" like Hive's.

    I've heard, but haven't seen, folks drilling on both sides and adding turn signals/blinking lights/reflectors.

    As time allows, I'm going to go back through the testimonials, post the pix I can capture, and we can make this thread stictly "adaptations/modifications".

    I've never drilled a hole in one yet, but the trailer hitch and blinking lights seem like a worthy improvement.

    Please bear with me, this might take 10 "editings" to get the pix posted, but if you've ever drilled or cut the axle mount, jump in and post a pic/link/whatever to describe the "why's and how's".

    Give me a half hour, and I'll get the first few thumbnails under this intro, I'm starting at the top of the GEBE page, may get halfway through before sunrise.

  2. bamabikeguy

    bamabikeguy Active Member

    This will be where the thumbnails go

    Construction zone: compuIdiot at work - Pardon my dust...

    Update 1 : Heres the first six - more to follow- (triplets born yesterday, gotta walk the pasture...)

    Update 2: Beast's "disguising the engine as a milk crate" qualifies in this thread, a unique idea worthy of expansion when you get to looking at it...

    1. Bill in Calif - saddlebags

    2. Bill from South Carolina - saddlebags

    3. Edd from UK - saddlebags

    4. Ed in VA - saddlebags

    5. Mark from VA frame mounting

    6. Pat from Alberta - I dunno WHAT that is :rolleyes:

    Attached Files:

    Last edited: Aug 12, 2007
  3. bamabikeguy

    bamabikeguy Active Member

    9 more pix- more to come later

    1. Darryl in Colo- gas canister

    2. David in Colo - mounting block on bottom of axle mount

    3. Fred in Alberta - saddlebag

    4. Richard in Indiana - gas canister

    5. Jay in Ohio- rack behind seat with brace

    6. Joe in NY - double gas canisters

    7. Bill in Delray FL - convert to frame mount

    8. Jose in Mich- saddlebag & carrier support

    9. Tim in NC- something weird on a recumbent

    Attached Files:

  4. bamabikeguy

    bamabikeguy Active Member

    Attached Files:

  5. Starrman15

    Starrman15 Guest

    In Axle H*&^ again!

    Bama, I checked out Willies creation & I have one of those exact bottles
    SO IF I KEEP the Robin, this looks like the most practical way to go!
    Pretty simple, but smart alternative to the unfortunate placement of the Robins fuel tank.

    But I digress.....
    I have purchased a new bike & the axle I got from GEBE is crossthreaded (after many on & off's/reassemblys etc) & I guess, useless.

    So I went & purchased a new axle that is 7 & 1/4
    (the GEBE measured out to that but I might have been a little off going through the spokes etc.)
    & it is BARELY long enough to bolt everything up nice & snug right now.
    So if this NEW axle is even a hair shorter, it will not work.

    So I saw the "Bill in Delray FLA" convert to frame mount.
    This seems logical all the way around for fixing flats, changing tires etc.

    So I ask all of you HOW CRUCIAL are the measurements before you go & hack part of the mount off?

    & how would you go about doing so & feeling confident that the mount is in the exact position it would be (bolted to the frame) as it would be sitting on the axle?

    The GEBE mount looks like it was designed to sit on the axle & the belt tension align perfectly!
    I am interested in doing this mod but want any & all input before doing so!
    BTW, somebody MUST make an 8 inch axle.

    That should be & come standard along with the GEBE kit since so many people are having trouble in this area.

    Any & all input Greatly appreciated!!

  6. bamabikeguy

    bamabikeguy Active Member

    Sam has a detailed description of how he did it, but offhand in my opinion, you can have a quarter inch of "play", taken care of by the tension arm.

    With a bit of planning, you should be able to hit it exactly in the first shot.

    If I were doing it, I'd measure the existing gap from the top of the tire to the bottom of the engine mount/arc of the axle mount, it's about the width of a 2 X 4, but measure and find something to "hold that gap" steady while you measure and finagle.

    Main thing is to get the axle mount angled correctly.

    Then you can take the engine mount off, and move the axle mount to where you are going to drill the holes, clamping it all together, with that "gapper" insuring proper placement, then taking the rear wheel off while you work.

    The important side is the spokering side, and whatever you do to that side can be duplicated on the sprocket side.
  7. Starrman15

    Starrman15 Guest

    Went with the "Stock Wheel" & a few GEBE "rants"

    Well Bama, the Stock wheel turned out to be 14 gauge spokes.
    So I went ahead with it & saved alot of time in (not having to) switch the cassette.
    (The new bike had an extra gear on the cassette than the former bike)

    The conversion with the 7 1/4 axle went very well.
    My Dad again did an excellent job re-packing the bearings & this bicycle pedals better than it did off the showroom!

    Plenty of extra room for the mount also.
    More than the axle I got from GEBE even, so all is well in that area.

    90% of people purchasing a GEBE kit have to go & switch out the axle!!
    What is the PROBLEM here?

    This is an aspect to their company that really irritates me.
    They seem "obtuse" to some of the most obvious things they could do to "improve" their company & their customers sanity!
    To my way of thinking, this is just selfish, being tight, or plain stupid IMO.

    90% of bicycles have the "flip mechanism"
    Even in the Popular mechanics article they had to go to a bike shop & switch to a straight axle.

    As much as their kit costs, why not include an axle?
    Good Lord, How hard is that??

    But they WILL include a silly "KIll Switch"
    What in the world would anyone need That Thing for???
    On a Bicycle??
    I'd rather have had an axle included.
    (BTW, I have NEVER USED THE KILL SWITCH & ANYONE IS WELCOME TO IT....but you pay shipping)

    BTW, I purchased an axle yesterday at a very "high dollar" bike shop for around $10 dollars.
    (I purchased a few other things so I am not exact on the amount of the axle....but I KNOW it did not exceed 10 dollars)

    Now I will digress a bit farther & ask anyone who is "in the know"

    You CANNOT GET THEM OFF WITHOUT re-moving the brake pads to allow the wheel & tire to be freed.
    At least not on tires as big as I have.
    Now....those little "skinny tires" maybe....but not on a mountain or hybrid.
    This WILL NOT happen without completely deflating the tires.

    So...what is the point???
    Why would a company put these "flippy things" on a mountain bike wheel??
    Any answers would be greatly appreciated!
    What a stupid & irritating engineering mistake!

    Back to my bike.
    For the belt to clear the brake I am going to have to tilt the engine way back again like the Rossy.

    It IS a smaller Bicycle though.
    I really wanted to be able to mount the engine perfectly "straight up"
    Not only for "re-fueling" but for checking the oil.

    But that is not to be had.
    All in all, a good day though as problems were worked through thanks to a very bad experience last year & the help of this fine SITE!
    & the extra spokering came in handy!
    Will mount the Robin tomorrow or so depending on my schedule.

    Thanks again Bama', Ol' Pete, & everyone for your insight & help!

    Starrman 15
  8. bamabikeguy

    bamabikeguy Active Member

    I'm hoping this thread sticks with axle mounts and modifications, add-ons like saddlebags and auxillery gas tanks, blinkers, framemounting tips and such, so will make a comment on bikes/wheels over in the GEBE dooz and don't dooz.
  9. Starrman15

    Starrman15 Guest

    GEBE dooz and don't dooz

    Again Bama' this is a great thread also.

    Sorry for the "minor" rant.
    I realized I should have went back to my own initial thread for it after hitting "submit"
    I vented the rest in a pm to sam.

    BTW, Your air compressor idea is exactly what my Dad started using last year!
    & for the exact same reason!
    Being a mechainic, he had one around.

    I know your just a nice/helpful guy but GEBE ought to be cutting you a check every month!

  10. bamabikeguy

    bamabikeguy Active Member

    Thinking about framemounting more and more.....

    I have an Avalon sitting around, and there are 4 holes sitting there idle above the axle slot.... (pic 1) . And the only sized machine bolts on hand are the right size, wrong thread pattern. (pic 2)

    And since I have the camera/bolt, might as well check a Sun (pic 3) Schwinn (pic 4) and Huffy (pic 5).

    VERDICT? No one size fits all in this modification.

    Likewise, two R/S 35ers have done it in different ways, I have to choose between Sam's "3 Peice" and Lars "Get 'er Dun/drill a hole" designs....

    Sam's design

    Lar's design

    Looking at the YellowSun and Rocinante (pics 6 7 8 ) it is obvious the two holes won't fit on the axle mount width....

    Measuring the gap from the tire to the bottom of the engine mount might be deceiving, but on both Yellow and Rocin. the back is 1 inch, front is 1 1/4"... (pix 9 & 10) We'll check back on those measurements on the Avalon.

    Now, I'm not in any hurry to convert the Sun's, and Sam's design requires one very critical measurement when putting the thing together, but I'm leaning to that "3 Peice" method, which could be "mass produced" if I continue concentrating on Sun Retro 7's.....

    Just posting this to stress that YOUR bike will be different, Lars easier method might work for you, but I like the "detachability" of Sam's method.

    Attached Files:

  11. smapadatha

    smapadatha Guest

    Frame Mounting a GEBE/Kit (One Approach)

    (A leetle more detail than the post on my thread. I'm... pretty sure this is how I did it.)

    Step 1)

    First I mounted the GEBE main bracket in its “normal” position, attached to the rear axle.

    I measured the distance between the top of the tire and the “inside” of the bracket. On my bike this was 20 millimeters, but your measurement could vary.

    Step 2)

    I took a scrap of 3/16” steel and made a simple bracket. The bracket attaches to the existing 5mm holes in the rear fork. These holes are where you would normally attach a bike rack or fenders.

    Using guesstimation, I drew a reference line across my bracket. After I cut down the GEBE main bracket, this was where the new end of the GEBE main bracket was going to rest.

    Exactly where you draw the reference line isn’t that important. I drew it where I thought there would be good support for the brackets after I drilled all the holes, and after I had it all attached to the bike. What’s important is that, after you draw this line - DON’T MOVE IT.

    Step 3)

    I c-clamped the unmodified GEBE bracket to my bracket so that the end of the GEBE bracket touched my reference line.

    Then I bolted my bracket to the bike. The GEBE bracket was now in a “raised” position.

    After taking another measurement, I could see that when the GEBE bracket was attached to my bracket, it was 70 mm above the tire. That meant my bracket raised the GEBE bracket by 50mm.

    I unclamped the two brackets and cut the last 50mm from the end of the GEBE bracket on both sides.

    Step 4)

    I c-clamped the cut down GEBE bracket to my bracket, and put the new end of the GEBE bracket against my reference line.

    That’s why the reference line is so important. After you cut the GEBE bracket down, the new end of the GEBE bracket has to rest in exactly the same spot as it did before.

    With the two brackets clamped together, I put everything into a vise and drilled a 3/8” hole through both brackets. I repeated this on the other side of the bracket.

    I chose a 3/8” hole because both brackets are big enough to take a hole this size and still have a good amount of metal left. Also, 3/8” is very close to 9mm, which is a common axle thickness. I figured if a 9mm axle was strong enough for the normal GEBE bracket, a 3/8” carriage bolt should be strong enough for my modified version.

    Step 5)

    Next I put it all together:

    1. My bracket attaches to the frame
    2. The GEBE bracket attaches to my bracket.

    Because the end of the GEBE bracket touches the same reference line before and after it is cut, the GEBE bracket ends up 20mm above the tire, just like before.

    My modified bracket is less than 1/2 of a millimeter from its original position, so the GEBE belt fits perfectly.

    Another good thing about this design is that, although my bracket has 2 bolts and therefore cannot pivot, the GEBE bracket is attached to my bracket with 1 bolt. That means that even though the GEBE is mounted to my frame, I can still pivot the motor back and forth a bit, and decide how close or far away I want it to be from the saddle.

    Attached Files:

    Last edited by a moderator: Aug 27, 2007
  12. bamabikeguy

    bamabikeguy Active Member

    Thanks Sam....:grin:

    I was thinking about that initial measuring and marking, in the thread about "spreading a frame" theres a picture of my wingednut "axle substitute", to hold the rear forks together, which possibly could be used in this application.

    Two other possible ways to hold that mount steady would be
    a). using the two carriage bolts (3/8" or 9mm) that are going to eventually connect the pieces, (I might buy different lengths for my testing)
    b). even tie-ing a foot-long dowel in the axle slot, to slip the GEBE mount off and on really simply.....

    :arrow:In fact, just thinking out loud here, IF you put longer carriage bolts on that connection, the "dead end" threads sticking "out", could be used in a secondary way, hold something else, like one end of a bar or bracket, when capped with a wingnut. hmmmmmmmm.:?::?::?:
    Last edited: Aug 27, 2007
  13. bamabikeguy

    bamabikeguy Active Member

    One final thought about the beauty of "framemounting" the GEBE.

    By freeing up some space on the axle, a heavy-duty "training wheel" could be added to one side, to give stability to an uncertain senior citizen who keeps thinking about tri-cycles......

    Sam's tips don't mention the threading of the belt around the mount, just a heads up on getting that part correct.

    Afterwards, if the wheel is detached, the belt just dangles out of the way, no need to rethread it....
  14. larymor

    larymor Guest

    Nice job !!

    Great job Sam !! Excellent description and pics too. I just whacked mine off after the measurements , and drilled a new hole right through the frame and mount....I was in a hurry to get ridin'...your mount doesn't require drilling the frame which is probably better. Some of us dont have access to a lot of tools and such. I had to take mine to the gas station and have the guys there whack it off for it was a simple fix...after the whack..just drill a couple holes and drive off into the sunset. Here is the link to my frame mount.
    Last edited by a moderator: Aug 28, 2007
  15. smapadatha

    smapadatha Guest

    You're right, Bam. It's hard to see from the pictures, but right now the GEBE bracket is connected to my bracket with a 3/8" x 1" carriage bolt. That is actually plenty of room for a couple of other support brackets and a 3/8" nylox.

    In fact, the next experiment will be to mount an auxiliary tank in exactly that way (once I figure out how to connect the aux tank to the stock tank. Details to come...)

  16. bamabikeguy

    bamabikeguy Active Member

    So, Lars, because you didn't remove TOO MUCH of the axlemount, you could adapt your set up to one like Sam's, when he (or any other experimenter) figures out how to carry a 32 oz bottle/tank using those extra millimeters of thread.

    It looks very do-able.

    The mount itself is able to hold a bottle carrier anyway, it's just getting the tubing in there securely.
  17. bamabikeguy

    bamabikeguy Active Member

    EUREKA- why not a metal Army surplus canteen?

    It has the heavy duty snap on carrier pouch, which when utilized, would also hold the canister better on the bumpy parts.

    Unsnap, gas up, resnap and insert the tube/filter.
  18. Jim H

    Jim H Guest

    That's a nice setup smap... would you mind if I borrowed your idea for my own bike? It would make changing a tire a lot friendlier and save some serious aggravation. Really well thought out.
  19. Starrman15

    Starrman15 Guest

    I just bolted the mount on....

    Very impressive Sam!!
    That looks like the way to go, but for now I needed to get rolling!!
    Riding time in Ohio is slipping away!!

    SO....what I did on the left side of the axle that I thought was "crossthreaded"....was simply bolt the mount on.
    Plenty of room on the axle using this method.
    & I really TORQUED it down tight!!

    In the past (& on the right side of my bike it worked this time...but not enough room on the left for whatever reason.....) I always "sandwiched" the mount between the "nut" which tightens the axle to the frame & put another nut to hold the mount on the axle.

    Basically, the mount "SITS" on the axle but between two nuts.

    Well, like I said earlier, I just put the mount on the left side on the axle (that I was having problems with because there was not enough "axle" thread to tighten properly) & just used the "one" nut to tighten both axle & engine mount together.

    I have had not one problem & the bike runs smooth etc.
    IS this a NO NO???
    I have no idea why I "sandwiched" the mount in the first place.

    Any input would be greatly appreciated!

  20. larymor

    larymor Guest

    Canteen as fuel tank read my mind. In my "desperatley seeking a fuel container" quest many evil thoughts have entered my mind....First off...I aint gonna pay 5 bucks for a bottle holder for the fuel I salvaged one off an old junk bike...secondly off....I aint gonna pay 12bucks for a msr bottle... cause its just a bottle. which got me thinkin' , hey....when you stick a bottle in that salvaged holder it aint gonna stay put long...all the holes, in the roads in Fargo Dakotey. Whence my eyeballs fell upon a canteen in I read Bama's post...a myself. :cool: Yes...I could do a mount like Sam's. I will journey now in search of a canteen with holder and keep you guys posted.