Rock Hound

I ride a Tricruiser (recumbent tadpole) with 21 speeds. The crankset is a 48/38/28 (Shimano) and the cassette is 14-28 (Sram?). Anybody else have a better combination? I am thinking of going to a 11 or12-32 rear or maybe a 24/38/52 crankset. Or both. I want lower lows to save the knees and higher highs for the down slopes. But, I am wondering what the problems might be and if I just need to change out the whole system.

Any thoughts? Thanks.

Don aka rock hound

sukispop

Hi Rock Hound,

I'd probably leave your crankset triple as it is(it's got a pretty nice range, and shifting from one chainring to another should be very smooth), and look into changing out the cassette to an 11-32 or 11-34. That might require changing your rear derailleur, too, though. As far as the crankset goes, you might be able to just change out the inner and outer chainrings, which may be less expensive than upgrading to a whole new crankset. The mechanic at your local bike shop could tell you which modification(s) would be less expensive to perform, and which might make the most sense for your particular application.

Good luck!

bnet1

Sukispop has some good advice. However there is one Catrike owner in our local cycling club that converted his Catrike Road to quad (yes, that's four) chainrings. It seems to shift OK but what he got was a real wide range of gears. It modification was performed at a local bike shop but I don't know what was done to deal with the chain management and derailleur capacity issues.

jeff-o

On the catrike I'm renting for the week, I only needed the top two front cogs, I never even touched the smallest gear. What do you need 4 chainrings for???

Rock Hound

The ability to go to lower gears is important for some of us with bad knees. The lower gear takes the force out of a stroke, thus reducing pressure on the knee. There are other reasons why lower gfearing is an advantage: degree of hill slope; duration of slope; condition of rider; the list goes on.

Thanks to the rest of you guys for the info. I'll hit the local bike guy today and see which way is less expensive.

Don

jeff-o

Heh, will you hit him until it's less expensive?

areles

Rock Hound,

I'm using 52/42/30 chainrings, a 11/12/14/16/18/21/24/28/34 cog set and a 3-speed internal rear hub. That's 81 gears, all of them slow! There are a lot of overlapping or nearly identical ratios. Some days my bad knees like a 56.33 ratio but not a 58.50. I like a lot of choices - one of them has to be just right!

With 20" diameter tires, my gear range is from 12.95 to 128.77 inches. With 19.5" tires, it's 12.63 to 125.55. Neither low is low enough to climb a tree, but the highs are fast enough for me over level ground. It may take me a while to get up a steep hill, but I haven't walked yet. I've been up around 40 mph downhill, but wimped out 'cause I didn't know the road.

Ron

meb

Is that a cassette or freewheel?

At any rate, consider 11-30 or 11-34 as a low cost upgrade.