Friday, August 20, 2010

Wheel Building Dilemma

On Monday night, class at Broadway Bicycle School focused on wheel truing.

I brought the Shogun into Cambridge for class, because it has the oldest set of wheels in my fleet -- an old but otherwise nice set of mid-'80's Shimano 600 hubs (a 6-speed freewheel hub in back) and charcoal anodized Mavic MA-40 rims. I had meetings on Monday afternoon, so my once-delayed plan to go into town on the T didn't pan out, again. I did drive in early enough to ride around a bit, but then a thunderstorm hit, so I retreated to my car.

The truing exercise was surprisingly easy, particularly since we were able to use nice Park wheel truing stands. The wheels were both out of true -- a couple of millimeters warped across a half or third of their circumference, rather than having a particular trouble spot. Once they were straight, I could feel that the spokes were pretty unevenly tensioned, so the rims themselves may no longer be straight. And their sidewalls are pretty worn, so they could stand replacement at some point.

To that end, the wheel truing class was really the reason I took this course -- so that I could sign up for the wheelbuilding course, which I did yesterday! In just a few weeks, I'll start the process of building a set of wheels. The question, now, is what to build?

When I last posted about this, my plan was to build up a new set of wheels for my Columbia straight-bar cruiser, put a front brake on it, maybe get some cantilever brake posts brazed to the rear triangle, and make that into an errand/around town sort of bike. I even picked up a set of SR hubs, a single speed freewheel and a set of 26" rims. From a cash outlay perspective, I'd need only go buy spokes to lace up a set of single speed, fat-rimmed MTB wheels in class.

A lot has changed since then, though, and that project doesn't make sense to me anymore. The Columbia is going on eBay shortly (no calls from Craig's List), so I'm not really interested in building up wheels for it. I also think I'm going to offload those wheel components I'd picked up, because I don't see a project that'll require a set of 26" single speed nutted-axle wheels in my future anymore. So no -- not those wheels.

Other candidates? Well, I recently bought a set of inexpensive but decent 650B wheels to use on Juliana's Schwinn, and confirmed that 650B rims will work well with that frame, both in terms of bottom bracket height and brake reach. There is one significant problem with that wheelset, though -- rear hub spacing. The rear hub is a mountain bike hub, spaced at 135mm, and this is an older road frame spaced for 120 or 126mm hubs. I've tugged at and spread the rear triangle enough to get the wheel into place, but the dropouts are noticeably no longer parallel in that position. That may compromise how well the quick release bites the rear dropouts, which may be a safety issue. I also suspect the rear derailleur alignment will be problematic with that setup.

So a second wheel-building option is to build up a set of 6/7 speed 126mm wheels for her, using a set of freewheel hubs I have. These are nice 36-hole Specialized cartridge bearing hubs that came with the Motobecane -- the core of the wheelset I destroyed in my Schwinn's crash in May. That would be a nice wheelset for Juli, and it would work much better with her frame. If I take this path, I'd have to shell out for a new set of rims, and then I'd have that other 650B wheelset kicking around. Waiting for a build for Ava, I suppose.

Still another path might be to build up an alternate 27" wheelset for the Schwinn, or another 700c wheelset for the Motobecane. I could build lighter wheels for the Schwinn, or sturdier wheels for the Motobecane, for example -- the opposite of what's on each bike today. But the wheelsets on both of those bikes is well-matched to the way I ride them, and both have low miles on them, so an alternate wheelset really isn't necessary. I'd be answering a question I'm not asking myself, there.

I guess I could also rebuild the Shogun's wheels, since the rims probably ought to be replaced. But I'm probably going to sell that bike as a single-speed in the spring, after taking the derailleurs off for Ava's Fuji build, swapping the chainrings and chain, and screwing on a single-speed freewheel and some shifter boss caps. I may try my hand at re-dishing the rear wheel to make it stronger, but putting new rims on that bike would be little different than throwing money away on the Columbia. Worse, it'd cost more than that option, because I have no 700c rims lying around.

Given the choices, I think building up a set of 650B wheels for Juli's bike makes the most sense. It's not the cheapest path, and it will leave me with an idle 650B wheelset for a while. But it's the safest path for Juli, and of all the choices, it's the one that will provide the most utility. So I will need to find a set of 650B rims. Maybe a set of high-polish V-O Diagonale rims? Velocity Synergy symmetrics? Whatever I settle on, it seems I'll be doing my part to help the 650B movement along.

I'll try again for the bike exploration in Cambridge next Monday, with the Schwinn, this time. It has lights and a lock, and I'd be comfortable locking it up outside on a rack while I check stuff out. The last class is a front derailleur class, and it's as good a bike as any for that. None of my front derailleurs really needs adjusting, but I always have to fuss with them after a build, so I'm hoping I'll learn some alignment tricks. Picking up little tricks from experienced hands has really made the class worth my while, and I'd recommend it even to folks who've spent time wrenching their own bikes. Particularly, if like me, that's been a process of learning through doing, rather than learning through instruction.

All for now,



Richie said...

I'm a new reader to your blog, but have loved the few articles that I've read here today. Good stuff!

John said...

Thanks Richie -- glad you like it!