Front derailleur mounting

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sotal

Regular
I'm replacing my whole drivetrain with tiagra 4700.

My current FD is an FD-2203 tiagra triple with a clamp on mount. However the clamp and the FD are separate.

I got a FD as part of a set with a crankset and RD. The clamp is too small though. (I knew this when buying) I hoped that I would be able to use it somehow but the clamp on the FD 4700 is integral.

I expected my seat post to be a 34.9mm clamp. I just measured it with the Vernier caliper and it came out at just over 35mm on the post. Now I'm wondering if it is some kind of custom clamp mount to allow a braze on FD to bolt on? Or if a 34.9mm will be choose enough to fit?

Basically do I buy a braze on FD and bolt it to the current clamp? Or do I buy a 34.9 clamp on FD?

Thanks!
 

Sharky

Guru
Location
Kent
Is this the sort of clamp you need?
https://www.tredz.co.uk/.RSP-Braze-...zjmLmbkwh1NnQh1cm7GmkhKcbSSjgKxoC3jQQAvD_BwE#

At £8.95, I would take a gamble on the 34.9 clamp.
 
OP
OP
S

sotal

Regular
Is this the sort of clamp you need?
https://www.tredz.co.uk/.RSP-Braze-...zjmLmbkwh1NnQh1cm7GmkhKcbSSjgKxoC3jQQAvD_BwE#

At £8.95, I would take a gamble on the 34.9 clamp.

Not really, I think that is what I have got already. The original stock FD seems to be a clamp like that and what I guess is a braze on FD attached to it.

I ended up with a FD with a built in clamp of 31ish mm, so I can't use that. So I either need to buy a new FD with a 34.9mm clamp built in, or I need to buy a braze on FD and hope it bolts to the current clamp
 
OP
OP
S

sotal

Regular
535394

535395

535396
This is what I currently have would a braze on FD just bolt on to this? Would that be the safest option?
 

Ajax Bay

Guru
Location
East Devon
My current FD is an FD-2203 tiagra triple with a clamp on mount. However the clamp and the FD are separate.
No - you have a braze-on FD (in image) and a braze-on band adapter. Just get a braze on FD - 4700, say.
FD-2203 is not a Tiagra FD btw it's Claris, I think. Yet has resale value.
 
OP
OP
S

sotal

Regular
No - you have a braze-on FD (in image) and a braze-on band adapter. Just get a braze on FD - 4700, say.
FD-2203 is not a Tiagra FD btw it's Claris, I think. Yet has resale value.

That's perfect thanks - that is what I thought I had, I just didn't describe it properly!

You're right with it not being Tiagra, that was the rear mech that was tiagra.

Thanks again!
 
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