Homemade Sport Utility Bike (SUB)

Step 4 Frame Support

We need to prevent the swing arm from flopping over and make the bike ridable. I bought a 3 foot section of steel tubing and made a support bar that links between the swing arm (where the spring/damper normally would connect) and the kick stand mount.

I drilled the holes.... With a Dremel. Even that angled hole. Terrible, I know, but I made due with what I had.

This support bar is held at the kickstand mount with a half inch grade 8 smooth shank bolt. I had a grade 5 full threaded bolt at one time - it failed (bent). It was my fault, I didn't take the time to do the engineering (which I was capable of) and I would have easily seen that it was not sufficient.

Comments

[Hycro]

I wonder if there were a way to attach to the seat post bolt...I can think of a way, but it requires a piece of flat bar (Or is it called flat stock??) welded into the end of the tube that will attach to the seat post bolt, that is also cut in such a way that the bar rests against the seat tube, and the bolt just keeps it from moving around, but most of the pressure is on the frame...I don't know if what I suggested would even work, if there were welds, let alone if you just used all bolts...but if it did work, it could have the potential to be stronger than attaching to the kickstand mounting bracket...since on some cheaper model bikes, the kickstand mounting bracket welds are VERY cheap...

[adamlorenz]

any way to see more detail pictures of the tubing and how you connected them to the two sections... i'm at the point of doing this and i'm in need of some visuals before i start at it... thanks!

[trebuchet03]

Right now... the bike is 3000 miles away from me :p But.... If you look at a rear suspension mountain bike of this design..... The support tube goes where the shock- clevis joint is fastened with a threaded rod. The bottom portion is attached with a grade 8 bolt through the kickstand mount (there's also a nut down there). The tube had a hole cut on a bias to fit that bolt ;) Mind you, I only have rather simple hand tools -- that was cut with a hacksaw and cheapo power drril :p

[camp6ell]

i too would like to see a pic of where the support rod bolts to the main frame, when you do get back to your bike. thanks.

[trebuchet03]

Errr... not power drill.... Dremel --with the milling bit :p

[ctsp415]

Nice idea, have you figured out a rack system similar to the xtracycle for carrying loads. Otherwise it's just a very cool extra long bike.

[joshfromga]

i just finished a longbike of my own. my rack is an old wire-frame dvd rack. pics are here.