Convert triple chainset to Double

07Lapierre

Quick question...

Shimano Ultegra triple chainset. If I change it to a compact (or standard 53x39) chainset, will i also have to change the front derailer shifter lever?

Anyone do this before?

cheers

Lumen

A triple shifter works fine with a double.

The limit screw will stop it overshifting.

07Lapierre

Lumen wrote: »

A triple shifter works fine with a double.

The limit screw will stop it overshifting.

Thanks Lumen.

WithCheesePlease

Along similar lines and out of curiosity...

I have a Specialized Secteur Elite Triple with a Shimano FCR-553 crankset with 50 x 39 x 30T.

If I wanted to change that to a compact set-up could I just simply buy a compact chainring (from say here or here) and replace the 39 and 30 chainrings with a 34 say, and adjust the limit screw??

If so, which chainring should I go for to fit the existing 105 set-up? I have a Shimano 105, 10-speed, 12-27t cassette...

Lumen

The FCR-553 has a 130 mm BCD; compact chainrings are 110 mm BCD.

So no, it won't work. There might be other reasons too, I can't remember exactly how the chainrings attach on a triple.

WithCheesePlease

Balls. Ok, thanks.

cdaly_

Lumen wrote: »

The FCR-553 has a 130 mm BCD; compact chainrings are 110 mm BCD.

So no, it won't work. There might be other reasons too, I can't remember exactly how the chainrings attach on a triple.

The 52t and 39t rings bolt to each other with the spider sandwiched between. The 30t ring bolts directly to the inner face of the spider on about a 90mm BCD.

Single Malt

A triple front mech will not shift double properly because the cage is designed for the capacity to shift three. A triple chainset, used as double, will not have the two biggest advantages of double. The better chainline, and weight saving.

BostonB

Whats the point of switching from a triple to a compact? What will you do better having swapped?

WithCheesePlease

BostonB wrote: »

Whats the point of switching from a triple to a compact? What will you do better having swapped?

I'm not sure of the OP's reasons, but for me I usually avoid going into the 30t and only use the 39t on hills which leads to crossing if I'm in a 39 front - 27 rear, which I probably shouldn't be in. I'm already treating the bike as a double and I shouldn't so was wondering about swapping it over.

It's not to reduce weight or anything else, I just want to stop using the granny gear as everyone seems to call it.

funkyjebus

BostonB wrote: »

Whats the point of switching from a triple to a compact? What will you do better having swapped?

quicker shifting, a weight saving znd we'll all respect him a little more!

WithCheesePlease

funkyjebus wrote: »

we'll all respect him a little more!

The part I didn't want to admit to!

07Lapierre

BostonB wrote: »

Whats the point of switching from a triple to a compact? What will you do better having swapped?

I'm thinking of changing from a triple to a double as I'm fitter now than i was 3 years ago when i bought the bike. The triple has out lived its usefulness at this stage. I don't use the 30T any more so I thought I would change it to a compact or standard 53x39 (haven't decided yet).

If i had to change the chainset, front/rear deraillers and the shifters, I probably wouldn't bother, but i have a spare rear derailler (short cage) and a spare chain. so that just leaves the chainset and shifters. As the shifters are the most expensive parts, and are compatible with a double, its a straight forward conversion, which makes if a viable option to convert from triple to a double.

TBH i was hoping someone would come on here and tell me it couldn't be done, then I'd have a great excuse to buy a new bike!

07Lapierre

funkyjebus wrote: »

quicker shifting, a weight saving znd we'll all respect him a little more!

Thanks :rolleyes: