Bicycle Mechanics - request suggestions for a chainring and cassette size

I am in the process of re-building a 1985 Raleigh road bike into a bad weather/touring bike (not heavy loaded touring but day tours).

It originally had a double 52-42T chainring with a 6 speed freewheel (probably 13T-25T or similar).

I have had my LBS widen the rear triangle to fit an 8 speed freehub.

I want to be able to have enough gearing for steep hills, but yet have enough gearing for a bit of speed, this would obviously suggest that I need a triple crank.

HOWEVER, in order to reduce cost of rebuilding this bike I want to use the original BB and double crank set to acheive the same result (speed and hill climbing). Actually the BB has been changed 4 times since 1985 but it IS the BB and crank that came with the bike when i acquired it.

I have come to the conclusion that I have to sacrifice one or the other and can't have both. I would definately want the ability to climb hills easy rather than the speed.

Sooooo, I have settled on a 46-36T double crank with an 11T-30T 8 speed cassette.

In yer guys opinion, to you think this would offer enough gearing for easy hill climbing (while seated) for your average 33 year old, roadie? Keep in mind I would rather have hill climbing ability than speed (but I want speed too!).

Or there other things to consider with this set up?

Go here and you will see a picture in a previous thread I posted
http://www.bikeforums.net/showthread.php?s=&postid=219973#post219973

Thanks

Digger

Are you able to change the rings from the 52-42 or are you changing the entire crankset? If so, you should be able to install a triple, especially if your shifters are downtube or bar-end shifters (i.e. friction on the left side).

In terms of high gear, with 46-36 and 11-30, your new high will be slightly higher than it used to be. And unless you live in a flat area or are a strong guy (but watch those knees!), your low won't be very low. I would suggest either a road triple with 52-42-30 and a close high-range cassette like Sheldon's Cyclotouriste 14 (14-34), or a double like you have planned, with with more space between rings. Something like 46-30 or 46-32 would be great unless you have killer hills.

Regards,

Sunrace offers an 8speed 12-34 cassette. If your crankset is 130 bolt circle you could run 52t or 53t big ring and a 38t small ring. You will need to run a MTB rear der to handle the tooth difference. This will give you 117-119 inches on the big and 30inches on the low gear.

Unless you go offroad or on loaded tours, you probably do not need a low gear much below 40 inches. Unless you are in the Tour de France or like to mash high gears, you do not need a high above 100 gear inches. Because front derailleurs are more primitive than rears, you can generally obtain better shifting by using a wider range in back and a tighter drop in front.

On my road bikes, I use 52-44/14-28 (14 speeds), 45-42/13-26 (12 speeds), 48-45-34/13-23 (18 speeds), and 50-42/13-26 (14 speeds), respectively.

I have a stronglight 80 chainset which I setup with a 36/48 for general urban commuting, using a 12-28 cassette. I found it gave low enough gears for hauling shopping and accelerating at the lights.
When I moved to a place with really steep hills, I kept the gearing and coped OK. Later I changed it to a 28/38/48, adding a third chainring to the same set of bolt holes, and that eased the climbing a lot.
Most standard road chainsets can only take a 39 t. If you want smaller, you need to hunt around for a chainset with a smaller diameter bolt circle.

Don't forget that you must have the correct rear derailleur with a long cage to handle all that extra chain slack when you use such a large rear cassette. Going from the small chainring/small rear cog to the large chainring/large rear cog requires a long cage to take up the slack. Have fun!