Foxonabike

I was given a 24" wheel MTB in decent condition and wanted to try and make a SUB (stand up bike) Removed the top tube and most of the seat tube. Dropped the top of the rear triangle and braced to the main tube. Made a stem from 30mm stainless tubing and a hinge to fold the bars, fits easily in the back of my car. All gear mech removed and chain tensioner made. Cranks cut down to 90mm, gives a much better pedalling action. Technique is a bit different than riding a normal bike, like climbing stairs but you're getting somewhere, I tend to pedal and coast, head wind is a killer. I use it on the local bike trails which are quite flat (old train tracks) so single speed works. Turned out better than I thought it would.

Original frame


Frame cut down


Painted black


Folding bars


Hinge


On the trail

FiftySix

Real nice work there, Foxonabike.

90mm cranks sure seem short and low on leverage to me. Is that a common crank length for stand up bikes?

Foxonabike

I don't think so, but the action is really good. And they are a thing.

https://www.ebay.ca/itm/SUNLITE-FORG...0AAOSws8Zad4sc

FiftySix

True, they are a thing. I thought that size of crank was originally designed for kid's bicycles.

The real question is how it works with your sprocket gearing and if the short cranks make stand up pedaling more stable for the rider? And what speed range is that bike able to cruise at?

I have no idea personally, but I am curious how well it works for you?

Foxonabike

I must have short legs or something but it feels good, it did raise the gearing a lot so I increased the rear sprocket by 2 teeth. Definitely makes it more stable for me. I'm not sure on the speed, maybe 15k ? not high speed but a real hard workout on the legs.

FiftySix

A really nice build. More than I can do, that's for sure. Looks like great fun.

OldCruiser

Just one question. Why ? Because you can , I guess .

Foxonabike

Exactly, messing with stuff is my thing

Philphine

i've noticed trials bikes made like that. is that what you do?

Foxonabike

No, never tried trials, but the bikes do look neat. Going to try a bigger rear sprocket (+ 3 teeth) just to see what it feels like, got to add a link to the chain though for that
And I do have another 24" wheel MTB, it has an alloy frame so is pretty light, I would have used it for the stand up but wouldn't be confident doing any welding on it, might be time to try a trials

Destruktoren

Looks like a cool project, good work!

wltr w8 

That's cool. Does it rock side to side much when pedaling?

Foxonabike

Yes, a bit like this I can keep my upper body completely still but it is much harder on the legs and core, certainly a good workout, got some riser bars to try as well to see if higher bars feels better.

Fastfingaz

,,,,,,,,,, your work looks really good , final product great, what's the longest ride youve done on it ? That's really all leg work do you miss the seat any ?

Foxonabike

10K is a good workout, don't miss the seat on this, it's just a different way of riding (is it riding without a saddle ?)

Geepig

Nice one, it is way better than mine...

y0x8

Fun! As a fan of Fixed Gear, I would recommend trying Fixed Gear. Without a run - out, it would be even more fun!

Shwuno

Looks real cool

justrhines

Very cool. thanks for sharing

Alex57915

Your efforts results are very fruitful.