Old 01-21-10, 10:59 PM
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tippy
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Originally Posted by glittermoomin View Post
Hi there all!

I have a silly novice-type question regarding ten-speed bar-end shifters.

I just purchased a project bike to do up - a gorgeous red Schwinn World ten-speed road-style bicycle - which I'm hoping to convert to an upright commuter ride.

To do this, I'd like to switch out the drop bars for more back-friendly albatross bars, and at the same time, replace the dodgy old-school friction stem shifters with lovely, wonderful, smooth, no-hassle bar-end shifters. I have bar-end shifters on my Trek 520 touring bike, and love them.

My question is this....

I've done online searches for ten-speed bar-end shifters, and the best ones seem to be Shimano's Dura-Ace 10-speed bar end shifters SL-BS79 - http://www.bikesomewhere.com/bikesom...4049/30287?g=1

Okay, here's the silly part of my question..... are "ten speed shifters" designed for ten speed bicycles?

The only reason I ask this, is my Trek 520 has 21 gears, and yet it uses Shimano Dura-Ace, bar end NINE speed shifters. Surely, it would use 21-speed shifters, riiiight? The rear cog of my Trek has nine gears, but the whole bike has 21 gears.

So.... should I be looking for five-speed bar end shifters for my little Schwinn ten speed, because its rear cog has five speeds?

Or.... am I missing something? (Go on, humour me!) I'm just a little flummoxed. Any help anybody could offer would be very very greatly appreciated!

Thankyou so much.
In older times, the "speed" of bikes were based on the total number of gear selections; IE # of rear gears X # of front gears. Thus a 10 speed bike could be a 5 rear X 2 front or maybe a 10 rear X 1 front. I guess the "math" is still true today however most just go with the separate numbers rear and front, IE 9X3 instead of calling it a 27 speed.

Shifter "speeds" are based on the number of "gears" its intended to shift (not the total for the bike). IE: A 9 speed rear shifter is for a bike with 9 rear gears (9 speed bike, 18 speed bike, 27 speed bike). BTW, how do you get a 21 speed bike with 9 rear gears? 9 X ? = 21?
Was it originally a 7 speed on the rear IE: 7X3 = 21 but then was upgraded to a 9 speed rear?

For a 10 speed bike, the rear shifter will be a 5 speed shifter (5X2=10)
You would only use a 10 speed rear shifter if you actually had 10 rear gears.
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