Two Wheel Blogs

but trying.

I don't know who said that but I live by those words. If I don't know something won't work I'll just go ahead and try. Worst case, I fail. Well, worst case I get myself killed, but I don't usually try stuff like that. I'm not only 2 old 2 go slow but I'm 2 old 2 be that stupid.

Anyway, when I try something and fail it's an opportunity to learn something. It's an opportunity to learn:

1. it can't be done
2. I can't do it, or
3. I can't do it that way, so maybe I should try some other way

One thing I've been wanting to do lately is to install one of my SRMs on my Surly Karate Monkey. I really wanted - still want - to know how much power I'm putting out and how much TSS I'm accumulating out there in the woods. Estimating it is OK, and it appears I'm fairly accurate with my estimates judging by performances predicted by my Performance Manager chart; but still it's just an estimate. Why estimate power when you might be able to get real data?

I wondered aloud to the Unit whether any bottom brackets out there might work. He did a little research and found a knowledgeable wrench who said a Shimano XTR bottom bracket should do the trick.

So we ordered one up. I also picked up the necessary bottom bracket tools, a Park Tool BB2 bottom bracket tool and a Park crank extractor, to do the job. With all parts and tools at the ready we started wrenching.

Well you already know this is a story about failure. Net-net, it didn't work. The Shimano XTR Bottom Bracket just isn't quite long enough to provide adequate crank and chain ring clearance when mounted in a Size Medium Surly Karate Monkey. We either saw left-side crank to chain stay interference, or chain ring / chain stay interference, depending on which side we mounted the bottom bracket spacers.

Now that's a real shame. It means I will have to continue to estimate TSS for my trail riding. It means I won't have the benefit of power meter feedback for the Ouachita Challenge. And it certainly means that my next mountain bike most likely won't be based on a Karate Monkey frame. In fact, I'll even go custom if that's the only way to get a bottom bracket in a single speed 29er mountain bike frame that's SRM compatible.

Now I know what your thinking: There's just something not right with mounting a $3000 bicycle power meter in a $400 frame. It's so not right it shouldn't work.

Ah, but that's just another reason to try in my book.