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The Plastic Fantastic / my busted plastic bitsa

Bike tags: Road bike | Commuter | bling | carbon | dura-ace | more tags >>

Specialized Tarmac Elite / 54cm / '08 / 7.17kg

Kuota carbon/kevlar 42cm / Ritchey Pro 120mm, 8�

LOOK HSC4 SL / ACS Maindrive integrated 9/8"

Shimano RS81 / Vittoria Open Corsa CX 23mm / PZ Racing skewer

Shimano RS80 / Michelin Pro3 Race 23mm / PZ Racing skewer

SRAM Rival 130mm, 172.5mm / no-name 'ceramic' ( BB)

Karbona / FSA carbon 27.2mm, 20mm setback

modified Shimano PD-A550 / Dura-Ace 7801

SRAM RED Black / original RED RD, RED Yaw FD

Shimano Dura-Ace 7700 DP front, Shimano Dura-Ace 7400 SP rear / SRAM RED

12-23 Dura-Ace 10s / SRAM Rival 53/39 / Aerozine chainring bolts / Alligator iLink cable housing / modified KCNC expander plug / PZ Racing carbon seat clamp / Selle Italia 5mm Smootape

Frameset came from a friend of a friend; he'd broken it in a crash but it was pretty minor. I scraped the paint off the damaged area for a look (it's just above the FD hanger), and there's a 1cm horizontal crack; NBD IMO. This is an American bike, built for fat, litigious Americans, and at 1.2kg is doubtless overbuilt for my purposes; I could just about cut the seat tube out entirely, looking at that downtube. Covered the spot with tape in lieu of paint, not just for cosmetics but to keep the UV and H2O out.

Already had the wheels with the red nipples, and the stem with white and red graphics, so the red bling treatment was a natural as soon as I got my tax return ; )

Of course, I know you're meant to run a spacer above the stem with a carbon steerer, but that's ugly, and since this frameset cost me $ 0 (and since all the red bling could be used on any number of fancy plastic framesets), I thought I'd perform the experiment. I figure doing up the lower pinch bolt a smidge tighter and the upper one a tad looser will offset the steerer's tendency to be compressed into a taper with one end inside the clamp.

Naturally, the amount of steerer inside the clamp should be maximised, so I gave it an internal chamfer and modified the expander plug to be countersunk. I felt the expander was overly hefty, so I went nuts with the files and dremel, reducing it to its bare essentials. The shape of the extrusion made for a pretty complex shape when I was done; it's a hidden gem.

No issues to report with the naughty steerer cut. But then I'm only 65kg.

People who friended this bike campystamp, dnm_25

Nice setup

Funny part about frame repair. I've got a friend who works with carbon fiber all the time; he advises "fill in that space with resin, or apply a CF patch w/resin" and it may well be fine.

Nice color mix, nice KCNC expander. Ride it like you stole it.


Like with the flush-cut steerer; it's a bet and experiment - my mechanical intuition versus the blanket rules of common sense.


Nice one, but was that crack really made for -as you put it- 'fat, litigious Americans' ? As you have seemingly fixed it with a bit of Scotch tape, whom do you consequently plan to sue ? Btw, a company around here claims that they actually repair carbon frames, and your frame seems to be worth it.

P.S.: Referring to your other post with its 'messed-up geometry': Once you level out your saddle(s) like you did on your '1995 Giant CFR1', the geometry will certainly improve.

Pff, sue

I live in a country with a civilised health system, meaning I don't have to find someone to sue should my bike asplode and put me in hospital.

Besides, it's simply not a consideration. How catastrophic do you think a failure at that point could be? If you had any engineering nous, you'd be criticising me for cutting my carbon steerer level instead, which is another, higher stakes bet I'm making on my own judgement.

I assert that what looks like two major no-nos are in fact totally NBD in this case, all factors considered. I back up that assertion by putting my neck on the line.

As for messed-up geometry, that's not about my seat angle; that refers to the unnecessary toe overlap, a too-short top tube, wrong head and seat angles and less than optimal weight distribution; IME that stuff is a lot better when the frame's a bit too big.

My seat angle is an improvement; that CFR1 was stolen last century. I've since experimented and found something closer to my personal optimum, thanks very much. Have another look at my Hillman page for a detailed answer to a question about it.

You should probably ensure somebody's a noob before presuming to dictate position to them.

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