General Cycling Discussion - Crankset Question

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Mr. New Dilemma
08-12-10, 07:42 PM
I'm sorry if you guys get asked the same questions over and over again.

I recently purchased a used 98 Cannondale Caad 3 R1000 frame. I was riding a 2007 KHS Flite 250. I switched all the components from the KHS to the Caad 3 except for the BB and the front derailleur (toasted). I finished the bike and just returned from the second ride on it, and I have a problem I did not have on the KHS.

The gearing feels to easy. Does that make sense? I went to climb a few hills and never even had to drop to my small chainring. But on the flats, I could only generate about 28mph in the gearing. So i did some research.

The KHS came with a 50/34 crankset. Now I am not sure what the Caad3 came with, but looking at some new cranksets, I see the numbers 53/39 come up quite a bit. Does this seem like a more appropriate crankset size now that I am dealing with a more efficient frame and a new smooth BB?

I read Sheldon Brown, but honestly, he confuses me. Any help would be greatly appreciated.

http://i399.photobucket.com/albums/pp77/xjdefx22/102_0051.jpg

fietsbob
08-12-10, 07:51 PM
A 12 tooth cog on the cassette? get one with an 11t cog.
Mr. New Dilemma
08-12-10, 07:55 PM
SRAM PG-850 11-28, 8 Speed

That's the cassette.

rogerstg
08-13-10, 05:59 AM
If you are using the same wheels, cassette and crank on each bike, and your bike is mechanically correct, the differences are probably in your head.
knobster
08-13-10, 10:40 AM
+1, a new frame and bottom bracket aren't going to make that much of a difference, unless the bottom bracket was frozen up... :) I say if it's too easy to pedal, you need to find some hills...
fietsbob
08-13-10, 11:48 AM
If its so easy join USCF and get a racing license. and see if you will stay up front..
Mr. New Dilemma
08-13-10, 03:45 PM
If its so easy join USCF and get a racing license. and see if you will stay up front..

My favorite response so far!

What can I say? Maybe the old BB was so destroyed that it was adding extra resistance. (It felt like a pepper mill when I turned it by hand once the cranks were off.) Living in N. Georgia, hills are pretty much the norm, so it is not lack of hills. Anyway, does anybody think that changing the chainring sizes will make it better?
knobster
08-13-10, 03:57 PM
Not sure if better is the correct term. It'll give you higher gears sure. A rear cassette is cheaper than a new crank. I think I'd look into something like a 11/21 or something before I changed out the crank. Not sure what cassette you have now, but it's probably much lower than you need. 11/21 would be pretty sweet if I didn't have monster hills to climb.
Mr. New Dilemma
08-13-10, 04:09 PM
Hey thanks knobster! I will have to look into that. I just have to do more reading and really wrap my head around how the gearing works. (ratios)

I went up a hill today, dropped to my small chainring and actually had to look down to make sure my chain had not fallen off. Mind you, it wasn't the Col de Tourmalet, but it was a decent hill. Popped back up to my large chainring and was most comfortable 2 cogs down from the biggest on the cassette.