Triple to a Compact

scottyboy05

I want to change my Shimano FC-R453 triple chainset to a compact as I never use the small ring, is there much of a weight saving and what else would I have to change.

Spec; Shifters:Shimano Sora STI, flight deck
Bottom Bracket:Shimano BB-ES25, Octalink spline, cartridge bearing, 68mm x 118mm
Front Derailleur:Shimano Sora
Rear Derailleur:Shimano Tiagra

Cheers

sungod

aside fron the crankset itself, i would also change the front mech, you don't *have* to do this though, just re-align it with the new crankset

you'll save a fair bit of weight, esecially if you use a better crankset, also you'll have a slightly better chainline

the front shifter will work ok (i used to have a bike with a triple and sora shifters, changed it to a 105 double with no problems)

note that you can put a 10-speed crankset on, it'll be fine, there's a chance you'll get very slight chain rub when in the smaller ring (using a 10-speed chain will cure it)

i'd consider looking for a bargain pre-2011 105 crankset, they are *much* nicer than the sora ones, you'll probably need to change the bb

ribble has 105 5600 series compacts for 76 quid at the moment, you'll also need a hollowtech ii bb

http://www.ribblecycles.co.uk/sp/road-t ... HIMCHAR235


weight...

this says sora triple 1149g...

http://webcache.googleusercontent.com/s ... ogle.co.uk

this says 105 5600 770g...

http://www.competitivecyclist.com/produ ... 2.6.1.html

...the sora is quite a chunk of metal compared to the 105

btw you'll find all shimano's installation and adjustment instructions here...

http://techdocs.shimano.com/techdocs/index.jsp

the park tool site is also useful source of 'how to' info with pics...

http://www.parktool.com/blog/repair-help

markos1963

Why do you want a compact? If you aren't using the granny ring then the middle ring of 39t is the same as a standard chainset. You're probably too strong a rider then to need a compact.
Plenty of good quality standard chainsets out there at good prices. An Ultegra 6600 could be picked up for a song representing a good upgrade and weight saving. Match that up with a 6600 front mech and you're on the road to a decent build.

mrbrightside

leaving the standard sora shifters is there not the potential to drop the chain if you select the lower 'extra' gear by mistake?

My bikes not even got the the Sora spec triple, RPM CRD is in place so this is something i'm interested in doing.

Many thanks for the above advice...

markos1963

MrBrightside wrote:

leaving the standard sora shifters is there not the potential to drop the chain if you select the lower 'extra' gear by mistake?

My bikes not even got the the Sora spec triple, RPM CRD is in place so this is something i'm interested in doing.

Many thanks for the above advice...

If you use a 'double' front mech the limit stops will prevent the chain dropping off the bottom.

brin

I changed my front mech for that reason when i changed from triple to compact - only about £30,but can save a lot more if,as mentioned above happens, your choice

Mister W

If your triple is working okay then changing to a compact is a pointless exercise. If you don't use the small ring much then just don't shift to it. I've changed a bike from triple to compact and wouldn't bother again unless the triple was causing problems.