Speed

[rlhodges]

I need speed. I have a 13-30 in back and a 24-45-50 in front. Can I replace the 50 with a 52? (Trek 1420)

[painkiller]

I would recommend replacing your rear cluster to 11t or 12t -28
24-45-50 seems a bit odd to me. the tooth spread on the front is getting extreme, if you are correct.
5t from middle to big ring and 21t from small to middle? is that how the bike came? to be safe and in range you should bump up the small ring along with the big ring if that is the way you want to go.
and change the rear cluster and new chain would give you the most effect.

[nfmisso]

First questions;
* is your 13-30 a cassette or a freewheel?
* how many speeds in back?
* what is the BCD of your crankset? http://www.sheldonbrown.com/gloss_bo-z.html

If it is a freewheel, 13 is your limit. If a cassette, 12 or 11 is your limit, depending on your hub.

This is the only info I found on the Trek 1420:
http://www.bikepedia.com/QuickBike/BikeSpecs.aspx?Year=1993&Brand=Trek&Model=1420&Type=bike
It says in '93, it had 32/42/52 and 12-28 7speed cassette.

Bottom line, you can do what you want, or even go larger than 52T. I have a 52T steel ring, 130mm BCD and a 53T FSA alloy ring, also 130mm BCD) that I would be happy to sell to you, PM me if you are interested. Otherwise, you can get rings of eBay, Amazon and many other sources.

You may have to extend your chain, or be very very careful about not using the big ring in front and big ring in back at the same time.

[Joe_W]

Also: You should watch your cadence: I ride around 100 rpm (usually). It is much better for your knees.