View Full Version : How does my chain length look?


racerjake
04-11-2007, 12:25 PM
Hey folks,84209

84210

84211

I just rebuilt my bike with Rival. It was truly a pleasure to hang these nice parts.

I was pretty conservative when I installed the chain. The "Big-Big + 2 links" formula from the SRAM site seems a tad short.

Take a look at the two pics and let me know if you think I'm ok. One is with the bike in the 53x23 (i'm running and Ultegra 12x25), the other is in the 39x12. It seems ok but I haven't put the bike through any races or on any bumpy roads.

The last pic is in case you're curious about the whole build. I decided to get my old crusty ICE repainted, slap on the Rival parts, new bars & stem, and try to get a couple of more seasons out of the thing.

-Jake

www.mranchorman.com (http://www.mranchorman.com)

Mark McM
04-12-2007, 07:43 AM
That second photo looks like you are in the 13 sprocket, not the 12.

In general, it looks okay. In the first photo it looks like you could get it up into the 53/25 if you had to (not that you'd do it intentionally, but it is good to have the extra capacity if you ever shifted it up there accidentally). It looks it might be a bit more marginal at the other end; if you shifted into the 39/12, the bottom run of the chain might drag on the derailleur cage. This is a bit more benign (it usually just results in some noisiness), but it would still be best to avoid this.

If you can drop it into the 12 without the chain dragging, you're good to go. If you the chain does drag in the 39/12, you might want to investigate if it is possible to take out a pair of links, and still get it up into the 53/25 without the chain being so tight that it threatens to rip the derailleur off. If you can't take out the extra links, then you'll just have to live with the noisy reminder when you (accidently) drop it into the 39/12.

masshysteria
04-13-2007, 06:11 AM
Looks okay. Does it run okay? That's the real test.

I've been running big + big + 2 on my cross bike for awhile and haven't had any problems and can use the full range of cogs from either chain ring in a pinch.

Fivethumbs
04-14-2007, 05:03 PM
I tried the SRAM chain length method also and I felt like the chain was too short. It worked okay, but it seemed like there was a lot of pressure on the derailleur in the small front/big rear combo, where I do most of my climbing.

I then used Leonard Zinn's method from his book (Zinn and the Art of Road Bike Maintenance) and I think the chain length works better. Zinn says to put the chain in the big front/small rear combo and the derailleur pulleys should be vertical.

racerjake
04-16-2007, 08:03 PM
I put in a good ride the other day (before the floods!) with a couple of hills and two sprints. The bike shifts great. I feel like I got these parts for a steal. I'd recommend the extra chain length. You can always take out a link--can't usually add one with these mushroomed chain pins.