Tech question, advise needed on gearing set up

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Permalink Reply by vxla on September 27, 2008 at 1:16pm

Certainly to use any gearing you'll need a 3/32" chain; the SRAM chains are nice (as they offer a master link which makes removal easier for cleaning). Your BB spindle length shouldn't matter as much so long as it threads on w/o problem.

All of your shifters will be contingent on what gearing you decide to run, etc. How invested have you gotten, thus far? What do you need exactly?

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Permalink Reply by Kevin Mulcky on September 27, 2008 at 2:58pm

I need a downtube or barcon shifter, rear derailleur, rear wheel and cassette/freewheel and cables, and maybe a Nitto noodle or a Midge handlebar. I've got everything else. I'd like to get a derailleur that can handle a wide range. The dropouts look to be out of alignment too, i'm going to take it boulevard tomorrow. I'm getting excited. I just need to sell some stuff to fund my new project.

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Permalink Reply by Tommie on September 27, 2008 at 3:14pm

Just to make things easy search for 9 or 10 speed stuff. If things break you won't have to go searching for old used crap.

Also there's something out there that makes sure you don't throw the chain when you run multiple gears in back and don't have a derailleur in the front. I've forgotten the name of it.... go buy it.

I disliked Sram chains but this was when Sram first bought out Sachs--things may have CHAINED (HA! that might have been clever!) now that Lance is dropping a few mil into their r+d. I digress . . . I like KMC chains. I'm currently running the 9sp SL chain and its buttery and light. But as Levar Burton would say, "...you don't have to take my word for it."

Since you aren't planning on using a FD your chain line isn't super important. There is probably an optimal chain line though. 103mm seems a bit short and might not give you an optimal chain line when shifting into a low gear.

Check out Performance. They usually have rad deals on front and rear wheels. Do yourself a favor though and rock out to something slightly more expensive. The performance brand wheels (Forte i believe) have a history of falling apart.

Blargh!

T

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Permalink Reply by Chucko on September 27, 2008 at 3:37pm

You might want a longer BB. If you have a 9spd setup with a 103mm BB, you're going to have some major crossover going when you're in the lowest gears. Ideally you'd want a BB that gives you a straight line from the chainring to the middle of the cassette. That way you won't have a lot of crossover at the top or bottom end of the cassette.

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Permalink Reply by Kevin Mulcky on September 27, 2008 at 4:17pm

Chucko said:

You might want a longer BB. If you have a 9spd setup with a 103mm BB, you're going to have some major crossover going when you're in the lowest gears. Ideally you'd want a BB that gives you a straight line from the chainring to the middle of the cassette. That way you won't have a lot of crossover at the top or bottom end of the cassette.

Thats what i was fearing, would a long cage derailleur help?

And I'm definitely buying or bartering for used stuff. I got to keep this cheap. The Economy!!!!!!!!!!!!!

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Permalink Reply by Tommie on September 28, 2008 at 7:49am

A LC der. won't help. Think of it this way: In school the janitor always had a lot of keys and those keys were always on a chain. If the janitor didn't find a good way to manage that chain the keys would be gettin in his way, gettin' caught on cleaning solution, gettin' stuck in the broom or worse the mop squeezer-outer, etc. The janitor has a few options BUT usually he/she opts for the automatic retracting keychain---you pull it out, do what you need to do and then it magically reels itself in.

LC rear derailleurs do the same thing. You see, when you have a big gear in front and a big gear in back you need to have a lot of chain links so that you can shift into every gear and stuff. BUT having that many links means that they can get caught up in different places and get in the way when you're not in an optimal gear ration (34/12 etc). A LCRD takes up this slack as best as it can to help keep you from looking stupid when you're in a not-so-bright gear combo.

A LCRD won't help your chain line. It will help your chain slack. I suspect, though, that you won't be needing a LCRD or even a medium cage.

NOW, your chain line is affected by 4 things. What cog you are in the back, what ring you are in front, your BB length and your crank. You will only have 1 ring in front AND you'll be shifting sooo we're down to 2 options for an optimal chain line. BB and Crank. You already have your crank SOOOOO we MUST adjust your BB. I suspect you'll need something around between 109.5 and 112mm. Why? Because that's what Shimano offered for their double and triple cranks back when they had octalink BBs.

The word of Tommie . . . .. Thanks be to Tommie

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