Radian Cycles disc all-road

[Pi Guy]

Hey folks,
I'd been riding this frameset around sans paint for a while. It's the first disc brake frameset that I've made. I designed and cut out the dropouts/disc tabs from 4130 sheet by hand, so I wanted to test it thoroughly before throwing down for paint. Thanks much to Colorworks for the sweet paint job! Comments and critiques are always welcomed. Thanks for looking!

[AngryScientist]

very cool Pi Guy.

with regard to the dropouts and disc tabs:

what's the process? when you say cut by hand, you mean cut with what tool?

what's the rest of the operation? milling machine to take down the surface area that is not raised?

very PRO looking work, for sure.

[stephenmarklay]

Looks GREAT!

[FixedGear]

Beautiful craftsmanship. You will always have to ride this bike on the 14th of March each year, right?

8^)

[mhespenheide]

That looks awesome. Great blend of traditional lugs and lines with modern discs.

Why pi and radian(s)?

[Mzilliox]

I really like the look of this bicycle. color is real nice too.

wheels 650b?

what fenders are those? Berthoud?

[phoenix]

Perfect, I really like this bicycle! Well done!

[v531xc]

really nice! those disc tabs look like a nice design. Which fork blade and chainstay did you use for the braking side?

[Pi Guy]

Originally Posted by AngryScientist

very cool Pi Guy.

with regard to the dropouts and disc tabs:

what's the process? when you say cut by hand, you mean cut with what tool?

what's the rest of the operation? milling machine to take down the surface area that is not raised?

very PRO looking work, for sure.

Hi Angry,
That for the question. No mill here, at least not yet. The biggest piece of machinery I have is a drill press. I actually started this thing, and did the rear dropouts, a few years ago but then had a hiatus from any framebuilding until last summer. Anyway, here is what I did:

-Drew up my design in TurboCAD and printed it out on label paper.
-Stuck the design on the 4130 sheet and went to town with the drill press, jewelers saw, hacksaw, and files.
-The dropout faces, disc mount contact points and derailleur hanger threads are actually all braze in stainless. So no milling there.

Below are some pics of the process. The front dropouts and disc tab were done is a similar manner though weren't drawn up in TurboCAD. If you really want to kill some time there is a whole album of process pics on my Flickr. The dropouts and disc tabs were a lot of fun but took a TON of time. Don't think I am going to do that again anytime soon.















These guys in particular were a very big pain, with all the compound curves going on. LOTS of back and forth between checking fit and grinding/shaping.

[Pi Guy]

Originally Posted by FixedGear

Beautiful craftsmanship. You will always have to ride this bike on the 14th of March each year, right?

8^)

Thanks! And, yep...I don't think I have a choice!

[Pi Guy]

Originally Posted by mhespenheide

That looks awesome. Great blend of traditional lugs and lines with modern discs.

Why pi and radian(s)?

Thanks much. I really get a kick out of blending modern and classic elements. I try hard to get what I feel is the best of both those worlds.

I majored in math and so first had the idea to use the pi symbol as a headbadge. I felt pi tied well with cycling as cycling has lots of circles and rotational motion going on. I also felt that pi invoked a certain mathematical precision, precision which I really strive for in my builds. Plus I thought the pi symbol would just make a simple and elegant headbadge.

Originally I went with Pi Cycles, instead of Radian. I could call them "picycles" and it would be cheesy and wonderful. I went with Pi Cycles for my first handful of frames but then discovered these guys. So, I changed over to Radian as I could still use the pi symbol headbadge and maintain the math-cycling tie that I liked so much. I also thought Radian Cycles sounded pretty good. Honestly though if I liked the sound of my name more I would have just stuck that on the downtube!

[Pi Guy]

Originally Posted by Mzilliox

I really like the look of this bicycle. color is real nice too.

wheels 650b?

what fenders are those? Berthoud?

Thanks much and yes to both questions. 650b made working in "lug jail" easier and kept the rotational weight down a bit given the bigger tires.

Originally Posted by phoenix

Perfect, I really like this bicycle! Well done!

Thanks!

Originally Posted by v531xc

really nice! those disc tabs look like a nice design. Which fork blade and chainstay did you use for the braking side?

Thanks, the fork is Richard Sachs UOS fork kit. The blades are larger than traditional steel fork blades. I bought two kits a while ago and the blades in one were noticeably thicker walled than the other so I used the thicker blades too. I'd be hesitant to use the thinner blades, just a gut feeling.

The chainstay is a standard Columbus Zona. The chainstay end of the disc tab is still in a beefy section of the tube and is also pretty tangent to the cross section of the tube. This should result in more torsion than bending on the CS and tubes are great at resisting torsion. Some of the load gets spread to the seatstay too, so I didn't feel the need to go with an extra beefy chainstay.

With all that said though this was an experimental frameset that I built for myself.

[Seramount]

I used to work at Radian Corp...

always thought it was a cool name.

your bike is sweet.

[ColonelJLloyd]

I've enjoyed seeing this over the last several weeks. Great work. Looks even better with paint.

Props on the Columbine! I had one put on my custom too.

[Tickdoc]

Bloody hell thats nice...congrats!