Can this be done: Changing from a compact 3-disc crankset to a 2-disc crankset?
After having broken in my new bike with nearly 1000 commuting miles on it, I've come to the conclusion that the stock 3-disc crankset (22/32/42) gearing is too short for my needs, and that the best setup would be a 2-disc set with 32/50 gearing or something close to that.
Can I somehow install a 2-disc cankset AND keep all the existing hardware such as the 3x8 Shimano shifters (see pic), stock front(Alfine)/rear(Deorde) derailleurs (again see pics) and Shimano UN26 (68x113) square taper bottom bracket and rear 11/32 cassette?
Also if the above is somehow possible, which crankset would you recommend?
-OR- would it be possible to change the chainrings on the existing FSA/RPM AL-8 crankset to a range more compatible to what I need? (mind you, that I have checked around for a 24/34/48 crankset and found some cheap units which my LBS didn't recommend.)
Oh yeah, your MTB FD almost certainly won't work with a 50t; might wanna check out this thread.
To answer your question, changing the cranks will require a BB and prolly FD. RD will be fine, although the cage will be longer than required; a road derailleur might be slightly better but is hardly necessary.
This thread is starting to sound expensive... what if I could find a Deore/XT 24-38-48 Crankset (relatively cheap on the net) and pair it with a Deore XT 8-speed IG 11-28 cassette, would that setup work with the currently installed derailleurs and shifters?
Found this: Alivio FC-M-411 48/38/28 and it says that I need a B/B with axle length 122mm instead of the 113mm that's already installed.
Rans Rockst (Retro rocket) Rans Enduro Sport (Retro racket) Hase Kettweisel Tandem (redundent recumbent), Merin Bear Valley (The gopher).
When I originally built my recumbent I put a 22/32/42 crankset on it because that's what I had in my spares box. Shortly thereafter I bought a 48 tooth big ring and installed it giving me a 22/32/48 crankset. All that I had to do was to raise the front derailleur a little and lenghten the chain a little. Shifting was fine, but I use friction barcons for the front chainrings.
Riding-wise it was great. The 48 tooth chainring gave me more top end speed than I normally use. I did almost all of my riding in the big ring and only shifted down into the middle ring steep hills. I thought of it as a 48/32 compact crankset with a granny bail out gear (which I never used).
Bill, you want to spin me into an early grave! lol (don't forget, I'm a big Clyde!)
So what you're saying Retro is basically changing the front Crankset (can't find just the chain ring, already looked!). I remember bringing this up again in the past, and will probably proceed in getting a 28/38/48 like the one in the link in my previous post.
That 16 tooth jump from a 34 to a 50 on a compact crank is a slow shift. I know it's made me appreciate being able to spin at high cadences in the low chainring just to avoid it if I won't be in it for awhile. Going clipless has cut back on the amount of front shifting I need to do.