Suitable front derailleur.

[jamesofyorkshire]

I have a road bike with Shimano Ultegra Hollowtech 34/50 crankset with Tiagra FD. I'd like to lower the 50 ring to a 44. Two questions:

Where would I get a suitable 44 ring?

Will my present FD shift OK when the tooth difference is reduced from 16 to 10 and if not, what FD would? It's clamped, not braze-on.

Any suggestions appreciated.

[cycleruk]

Which model of chainset do you have ?
The one with the "normal" chainring or the sculptured one, 4 arm or 5 arm ?

[jamesofyorkshire]

It's 5-arm....and I'll say sculptured crankset. I'll say the big ring is sculptured....it's not 'flat' like they used to be. It looks like part of the crankset.

It has 'SGX 50 F' on it as well as 'Shimano' and 'Ultegra'.

It's 10-speed too.....I forgot to mention that.

[fatboy]

Is it braze on or clamp on? If it's clamp on then you could move it down. If it's braze on then you may not be able to lower it. It is worth noting that doubles are a lot kore forgiving and it might just work without changing anything.

[jamesofyorkshire]

As stated initially, it's clamped on. So you think it's worth sticking with what's on there already? I think I read somewhere that a FD designed to work with a tooth differential of 16 doesn't work well with less.

[gaz]

Shimano front mechs for doubles often quote a chainring difference of "16 teeth or less". I've had Shimano front mechs set up shifitng 4 teeth difference without any issue, late 80's models rather than anything current.

If you have the model number for your Tiagra FD you may be able to find the specific tech doc to confirm. Unless you think it might actually be a front mech for a triple I doubt that there's any need to do so.

[jamesofyorkshire]

OK. Interesting.

I don't have too much faith in the tech docs.....they're usually very conservative.

I guess I should just go for a smaller big ring and see if the present FD works. Now, where do I find a 44-tooth chainring to fit this fancy crankset.........

[gaz]

The tech doc for that crankset indicates a 110BCD chainring.

Readily available, so long as you don't mind it not being "sculptured".

[jamesofyorkshire]

So any 110BCD ring will fit? Doesn't need to be owt specific? That's good. I guess my LBS - Spa, should have something then.

I ain't too bothered what the bike looks like as long as it works. Actually, for an old fart like me, the less bling, the better.

[cycleruk]

So any 110BCD ring will fit? Doesn't need to be owt specific? That's good. I guess my LBS - Spa, should have something then.

I ain't too bothered what the bike looks like as long as it works. Actually, for an old fart like me, the less bling, the better.

If Spa is your LBS then how about this:-
http://www.spacycles.co.uk/m2b0s185p0/P ... -Clearance
Yes it's a 42T, but at £6 worth a try or take your disassembled crank in and do a size/fit check.

Or these at £23.
http://www.spacycles.co.uk/m2b0s210p305 ... cral-Outer

Let us know how you get on and how they look.