carbon road frame with cirular and symetrical seat tube

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fredN4
Posts: 103
Joined: 14 Oct 2012, 8:21pm
Location: 30200 France

carbon road frame with cirular and symetrical seat tube

Post by fredN4 »

Hi folks
anyone know of a carbon road frame with a circular seat tube I could use to employ a clamp-on FD, so as to mount my 46/30 chainset. Please dont warn me about using a clamp-on with a carbon frame!! many thanks.
rfryer
Posts: 809
Joined: 7 Feb 2013, 3:58pm

Re: carbon road frame with cirular and symetrical seat tube

Post by rfryer »

My 2012 Rose CRX has a clamp on.
mattsccm
Posts: 5114
Joined: 28 Nov 2009, 9:44pm

Re: carbon road frame with cirular and symetrical seat tube

Post by mattsccm »

My On One CX bike which is quite roady fits the bill. Disc or rim brakes?
gxaustin
Posts: 890
Joined: 23 Sep 2015, 12:07pm

Re: carbon road frame with cirular and symetrical seat tube

Post by gxaustin »

I use 46t chainrings on all my bikes and get away with using the braze on with my CF frame. The mech has a 8mm gap to the ring but it changes OK, if not quite as snappily as my bespoke steel frame which was designed for a 46mm ring. In fact the mech would hit the chainstay on the CF frame if I could set it much lower. To avoid that on another bike I use a CX (band on) front mech.
Jamesh
Posts: 2963
Joined: 2 Jan 2017, 5:56pm

Re: carbon road frame with cirular and symetrical seat tube

Post by Jamesh »

Some of the early carbon bikes would...

Planet X pro
Ribble evo
Boardman team carbon

Cheers James
NickJP
Posts: 804
Joined: 24 Sep 2018, 7:11pm
Location: Canberra, OZ

Re: carbon road frame with cirular and symetrical seat tube

Post by NickJP »

My wife has a carbon fibre DeRosa Avant with a round seat tube that takes an FD with a 34.9mm diameter clamp. But that's no longer a current model - she's had it about eight years.

Sugino and Wickwerks both make adapters to allow a braze-on FD to be lowered further than the braze-on tab allows. Here's the Sugino adapter on another of my wife's bikes that allows the braze-on tab and FD to be used with a 39t big chainring:

Image
fredN4
Posts: 103
Joined: 14 Oct 2012, 8:21pm
Location: 30200 France

Re: carbon road frame with cirular and symetrical seat tube

Post by fredN4 »

many thanks folks. I shied away from trying the FD with an 8 mm gap - maybe should have tried. Bought the Wickwerks adaptor. It brings the FD too low. Sawed off a bit of the FD mount to make it work. But I'm not convinced the adaptor will stay firmly in place. It shifted a bit once and my SRAM red Fd wasnt happy! Have now used a serrated washer to firm it up. Fingers crossed.
NickJP
Posts: 804
Joined: 24 Sep 2018, 7:11pm
Location: Canberra, OZ

Re: carbon road frame with cirular and symetrical seat tube

Post by NickJP »

fredN4 wrote:Bought the Wickwerks adaptor. It brings the FD too low. Sawed off a bit of the FD mount to make it work. But I'm not convinced the adaptor will stay firmly in place. It shifted a bit once and my SRAM red Fd wasnt happy! Have now used a serrated washer to firm it up. Fingers crossed.

I've never used the Wickwerks adapter, but I have the Sugino adapters on two bikes, and no problems on either of them with the FD not staying at the correct angle and location.
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