Building a light single speed

[stephenmarklay]

I am looking for ideas on building up a light single speed.

The general criteria is something like

1.Sub 20 pounds
2.Can accept at least a 32mm tire
3.Disc or long reach road brakes
4.Belt driven gets bonus points
5.Something will slight more aggressive geo for around town but also ready for that 50 mile day.
6. Most important - a really fun bike rather than a utilitarian bike.

I also would prefer a true single speed frame with 120mm spacing but I am open to bikes that can be geared too. I am also not sure what type of bars I will use so that is open. I guess ideally it would be more of a flat bar for urban use but comfortable enough for a Sunday longer ride.

Any ideas are appreciated. I find that many of you know a lot more brands and options that I do.

Thanks so much

[john903]

Hey there
It sounds like you are enjoying single speeds now that is great. I have a Curtlo
that Doug made for me in 2009 (wow.) It is my single speed all rounder made like you are describing but not aggressive geometry and has a steel fork and totally built up it was probably 22lbs. Maybe not super light taking it off the rack but once i am riding it I don;t notice the weight. Doug did a great job on it for a very reasonable price $1400 frame and for back in 09. On the other side I have an older Hampsten that just for kicks some times I strip it down to fix gear mode. It comes in at 17lbs and more aggressive geometry and I have ridden up to a 155 mi day on it in comfort (tired but comfortable.)
I guess what I am suggesting is scourer the classifieds for a cool old frame and convert it over or build up something you have now. My suggestion would be go custom and get exactly what you want.
Anyway have fun

[edward12]

The Gunnar Street Dog might be an option. It's a stock frame with road geometry. But you can order one with custom brake/tire clearances. As far as weight, you may be able to keep it at 20 lbs. with a carbon fork (e..g., Whisky No.7 RD+ QR fork).

The rear is spaced at 120mm. I have one with a steel fork. I use it as a SS and fixed gear (with a flip/flop hub). Great bike.

http://gunnarbikes.com/site/bikes/street-dog/

[Steve in SLO]

Random thought: CF cyclocross frame with an ENO hub.

[yinzerniner]

Random thought: CF cyclocross frame with an ENO hub.

Even crazier ....

https://sagetitanium.com/2020/05/12/custom-belt-drive-pdxcx/

Wiling to bet that’s below 20lbs. I had a sage Barlow frame briefly and it was roughly 1600g. If I built it up with big tires and mid spec aluminum kit it would’ve gotten to about 19lbs. With single speed could easily drop two lbs.

[stephenmarklay]

Even crazier ....

https://sagetitanium.com/2020/05/12/custom-belt-drive-pdxcx/

Wiling to bet that’s below 20lbs. I had a sage Barlow frame briefly and it was roughly 1600g. If I built it up with big tires and mid spec aluminum kit it would’ve gotten to about 19lbs. With single speed could easily drop two lbs.

Ok that is bad a**

[stephenmarklay]

Random thought: CF cyclocross frame with an ENO hub.

No that is not too crazy. Probably a really good idea.

[uber]

50 miles on a flat bar might be tough for me. I love my steel single speed cyclocross bike for tooling around, and for training. I didn't want track geometry, and I did want front and rear brakes. I agree a carbon fiber SSCX with disc would be the bomb. My steel bike has Paul Canti brakes that work just fine on carbon rims. I think a Ti SSCX would be just as cool.

[robt57]

I did ENOs for years. Nice quality solution that has low pork too.

After a tib/fib/plateau break, fixed gears and that knee is out, and also starting out over and over with 80+ GI SS is out.

Enter the SRAM Automatix auto shifting 2x wheel I built. 1:1 ration until [modded] 90+ RPM Over Drives to 1:37. Save knees on hills and starts @ 55 GI and then OD once rolling faster to 78 GI.

Did a 30 miler on my Molteni Mercks on Eddie B-day. Knee had no complaints. ;)

Also, disagree totally with the 120 spacing. A 130 with a perfectly symmetrical non dished rear wheel is as bomb proof as it gets. Why avoid taking advantage of that, no sense to me.

My Automatix is 36 Sapim Lasers, A23 and 28mm tires. Front a 28h w/Lasers A23. Rolls sweet and reasonable low rotational mass in the wheel/tire [latex tubes]. So between the 55 GI start up and wheel/tire that spin up pretty quick, it is a tin on fun to spend a day on.

Down side is the hub weighs a ton and 1/2. But not rotational. Steel bike, steel fork, steel rear 2x hub, bike is 20lb with pedals. And a 60-61 bike at that.

A nice carbon disc CX bike with ENO I could totally get with, my knee maybe not so much..

[smead]

Light weight and wanting discs and fat tires seems a bit at odds, but I'm sure you could build up something like that in the 18-20 range pretty easily. 120 spacing with horz drops for sure. Plenty of 120 spaced single speed hub options. If this is going to be a road bike, consider rim brakes (you really don't need discs on a fixie), you could build something in the 15 lb range, and trust me, riding a 15 lb fixed gear is great fun in the hills.

[R3awak3n]

Id get a salsa stormchaser and call it a day

[stephenmarklay]

The Gunnar Street Dog might be an option. It's a stock frame with road geometry. But you can order one with custom brake/tire clearances. As far as weight, you may be able to keep it at 20 lbs. with a carbon fork (e..g., Whisky No.7 RD+ QR fork).

The rear is spaced at 120mm. I have one with a steel fork. I use it as a SS and fixed gear (with a flip/flop hub). Great bike.

http://gunnarbikes.com/site/bikes/street-dog/

I have always liked gunnar bikes. Thanks for reminding me.

[stephenmarklay]

Light weight and wanting discs and fat tires seems a bit at odds, but I'm sure you could build up something like that in the 18-20 range pretty easily. 120 spacing with horz drops for sure. Plenty of 120 spaced single speed hub options. If this is going to be a road bike, consider rim brakes (you really don't need discs on a fixie), you could build something in the 15 lb range, and trust me, riding a 15 lb fixed gear is great fun in the hills.

I am fine with rim brakes. I am fine either way really. Thanks for the heads up on the 120/130mm spacing.

[stephenmarklay]

Id get a salsa stormchaser and call it a day


Thanks. I just saw that one last week. I do like that bike. I don’t love the color. I would like to see that in a different color.

[kppolich]

I'd get an older crockett in case you want to run geared or use it for CX in the future.

[R3awak3n]

Thanks. I just saw that one last week. I do like that bike. I don’t love the color. I would like to see that in a different color.

:) funny, I love the color