7.68kg Custom Steel "Petit Souris" Work-in-progress

[whilgenberg]

This is the starting point for a lightweight build for my fiance. Built the frame to fit her and it ended up being roughly a 51 cm frame. Built up with the best components I could afford at the moment, it still weighs a not too bad 7.68 kg (16.94 lbs) which considering it's a steel custom frame. There's still plenty of room for improvement which will happen a little while down the road when I build the carbon version of this frame for her and start my new job at Praxis (convenient source of parts. . .).

Frame: Custom built 51cm "Petit Souris" steel frame
Fork: ENVE 2.0
Stem: Bontrager Race Lite
Top Cap: FSA
Headset Expander: FSA Compressor Pro
Spacers: None
Headset: Cane Creek 40
Handlebar: Easton EA 70
Shifters: SRAM Red 10 speed
Brakes: SRAM Red
Saddle: S-Works Carbon Toupe
Seatpost: Thompson Elite
Seapost Clamp: Custom Bored Salsa QR
F Derailleur: SRAM Red Yaw
R Derailleur: SRAM REd 10-speed
Cassette: SRAM PG 1070
Crankset: FSA SL-K
Chainrings: Stock FSA
BB: Stock FSA
Pedals: Shimano 105
Chain: SRAM PC1091R
Wheelset: Bontrager Race X-Lite
Tires: Michelin Pro3
Bottle Cage:
Bar Tape: Generic SRAM

[Wingnut]

I like it...look forward to seeing it painted and finished!

[wpccrunner]

This thing is a beauty. I love the cable routing through the split top-tube. Very nice work

[mrfish]

Very nice.

Tell us about the recumbent in the background.

[LouisN]

Very nice work .

Curious about the weight of the frame...

How would that design be possible with CF ?
Shaping tubes separately, and glueing them after ?

Louis

[whilgenberg]

I am also curious about the weight of the frame. I forgot to weigh it before I built up the bike. I'll be stripping everything off before it goes to paint so I will update with a frame weight then.

As far as how I would make a composite version of this bike, I have two options on how to do that. The first is to do it the way English does and use the steel as lugs and replace tubes with carbon. It's the easier way to do it and will most likely be an intermediate step. The more difficult way of doing it would be to machine some bladder compression molded parts for the frame and then bond them together as is the industry standard. I would have to make some interesting parts in order to keep the twin top tube but I think it would definitely still be possible.

As far as the recumbent in the background goes, that's a weight weenie of a different sort. I'm the team lead of the Human Powered Vehicle team this year at Cal Poly SLO and we built that bike fully out of composites in order to drop the weight from the usual 60-70 pounds that these bikes weigh down to 48 lbs. Not light by diamond frame standards but we still built ourselves a pretty sweet carbon frame for that one. Bladder compression molded joints and the like. The weight of that frame was 2.4 kg which we are planning on dropping lower for next year as we had a fillet brazed steel lug in there instead of all composite which just about doubled the weight of the frame.

If y'all are interested I can post more details in a separate thread. I just figured recumbents wouldn't be of interest to people here.

[wpccrunner]

I wish my schools HPV team was that impressive. I think ours died off and I never had a chance to join the club. How'd you guys do in the competition?

[whilgenberg]

We did moderately well. 3rd in design 7th and 9th in the sprint and 17th in the endurance after we broke our frame. We were still good for a 6th overall though.

[Rush]

I love hi-tech recumbents.

[jooo]

More of the HPV is cool, especially more detail Re: construction. There's still lots of DIY interest here.

Also, it's still a race bike - not made for a sandal wearing weirdo

[Rush]

Also, it's still a race bike - not made for a sandal wearing weirdo

Too true!

[oldmuthariley]

interesting - looks like a Haro bmx freestyler.
you could do a frame stand on it

[austke]

Agreed. That Trike is wicked!!!