Trek precaliber 20 gravity bike

[Phranq]

My youngest kid outgrew her bike, but that doesn’t mean I did! Don’t worry, I hooked her up with a new bike before I mangled her old one lol. Lately I’ve been wanting to get back into gravity sports. I used to be REALLY good at downhill longboarding, and occasionally someone would bring out a gravity bike. Well I finally have the opportunity and motivation to do it, so here it is!

 

[Captain Awesome]

My youngest kid outgrew her bike, but that doesn’t mean I did! Don’t worry, I hooked her up with a new bike before I mangled her old one lol. Lately I’ve been wanting to get back into gravity sports. I used to be REALLY good at downhill longboarding, and occasionally someone would bring out a gravity bike. Well I finally have the opportunity and motivation to do it, so here it is!View attachment 163578View attachment 163579View attachment 163581

 

[Phranq]

The handlebar position was a bit slow and short for me, so I rigged this up. I need to shim the handlebars, but this bike is gonna be FAST.

 

[Phranq]

And also, I’m naming her “kerT”.

 

[Captain Awesome]

You going to counterweight it?

 

[Phranq]

You going to counterweight it?

I wanna fill the forks with concrete, or possibly fishing weights and epoxy. I have a layback seat post that I’m going to rig a section of handle bars to support my knees. I may connect car trunk struts from the knee rests to the bar ends for stability, and I’ll see how much it weighs after that. I may fix weights to the knee rests after that.

 

[Captain Awesome]

I wanna fill the forks with concrete, or possibly fishing weights and epoxy. I have a layback seat post that I’m going to rig a section of handle bars to support my knees. I may connect car trunk struts from the knee rests to the bar ends for stability, and I’ll see how much it weighs after that. I may fix weights to the knee rests after that.

I was going to suggest making use of that seat post hole in a similar fashion

 

[Phranq]

Quick mock up. This is how I plan on having it. The seat is just taped on for now. The riding position is extremely aggressive

 

[Phranq]

Some adjustments required, but I’m gonna call it a day and refresh my brain a bit.

 

[MattiThundrrr]

This is really fun looking, never seen a gravity build unfold before. Is there plans for a chest pad? That steerer tube...

 

[Phranq]

This is really fun looking, never seen a gravity build unfold before. Is there plans for a chest pad? That steerer tube...

I’m gonna run to the hardware store today. I’m probably going to wrap the top tube in a pool noodle or plumbing insulation or something. The steer tube I’m unsure of at the moment, it’s definitely sketchy, but I’m probably going to use some foam for that too. Part of me wants to make it really nice, but the other part of me says “you’re gonna crash sometimes, just tape it up and send it” lol

 

[MattiThundrrr]

Save a bit on the build, spend well on knee and elbow pads

 

[Phranq]

Save a bit on the build, spend well on knee and elbow pads

I have most of the parts just laying around from other builds, this one is on a really tight budget, but my wife is pretty happy I’m using stuff out of the parts pile I’ve accumulated. I ordered a full face motorcycle helmet the other day, and I may still have my leathers somewhere from when I used to race downhill longboards

 

[ifitsfreeitsforme]

wow. crazy.

 

[Phranq]

I wrapped the frame in an old bike inner tube, electrical taped it, took a part of a yoga mat, taped that, took an old seat, and hose clamped it as tight as I can get it. It’s super solid, fits my body shape, and makes this bike much safer. Past gravity bikes I’ve used, all your weight is in your hands and legs, this one you can use your whole body for the maximum amount of control if you need it.

 

[Karate Chicken Industries]

Post some Video when you get it rolling.

 

[MattiThundrrr]

This is far too cool Now you have me thinking about flipping my Donkey..

 

[Captain Awesome]

Now you have me thinking about flipping my Donkey..

Quoted for posterity

 

[Phranq]

 

[Tallbikeman]

The ultimate validation is the video you will take of yourself at 80mph coming down some hill. The photo of you on the bike hurt certain parts of my body. Beyond that I hope the frame geometry is right and you survive in good health to raise that daughter.