Wednesday, June 24, 2009

Clydesdale among the Thoroughbreds

Dang it! On Monday I got home and noticed my rear wheel was out-of-true. (As had also been the case that morning, when I did a quick-adjust.) I pretty much knew what that meant, and a closer inspection confirmed my fears. I'd busted another rim. (Less than 1700 miles. Dang! The tire outlasted the rim... what's wrong with this picture?)

The harsh reality is... bicycle stuff - at least "road bike stuff" - is engineered for people who weigh less than 200 pounds. And I haven't been on the downside of 200 pounds since I was 15 or so.

Another harsh reality is... I'm, um... "thrifty." I refuse the $100 solution, if I can make do with $25. That's one of the most powerful incentives to have a bicycle as an alternative to a second car.

The broken rim (as in recent past) is a Mavic MA3. It's at the low end of the Mavic line; I think I paid $25-30 for 'em. I'm sure it's a fine rim, and would probably last for years and years if the bike pilot was 150 pounds instead of 250.

I build my own wheels... actually I'm getting quite good at it. It takes about an hour to build, and another hour to fine tune the spoke tension and get it nice and true. (It's science and art, and I take considerable satisfaction in ending up with a sweet-riding wheel when I'm done. And building my own meshes nicely with my "thrifty" approach to life.)

My wheel-building would be suspect if: 1) the wheel were in constant need of adjustment, or 2) it was the spokes that were failing. Both of those symptoms were fairly common with my first couple build-jobs.

But nowadays I ride away on the new wheel, and maybe fine-tune the truing a couple days later... then check it every 500 miles or so... and then the rim fails. (The softer alloy metal around the spoke eyelet gets fatigued and breaks. It's almost certainly caused by a 250-pound rider pounding down on it, and a succession of bumps, ruts, etc., pounding up. I try to pick the smoothest spots, and "stand up" over the bumps, but out there in Public Roadway Land, you take what you can get.)

On Monday night, I swapped my last new MA3 rim onto my riding wheel. (I have a spare built rear wheel hanging in the garage, but I hate to use the spare. The spare is currently MA3, too.) I've got a heavier-duty Mavic touring/tandem rim; it will be the next one. And hopefully this Clydesdale will get a few more miles of service. (A year would be nice...)

The late, legendary Sheldon Brown imparts wheel-building wisdom HERE.


Spirit of the Season said...

I've been riding Mavic 317/36 hole rims that I had built up and after about 1K miles I have not yet had to even true them and I am over 300 lbs.

Just a suggestion.

Bikeboy said...

Thanks, Spirit! (It's always comforting to know of other "Clydesdales" out there!)

Actually my on-hand rim is a Mavic A719, but I've been eying the A319 (ALWAYS 36-hole!) because it's substantially less expensive. (It looks to be identical to the A317 except it's for traditional rim-grabber brakes, and the 317 is for disc brakes.)

Michael Carpenter said...

I'm a little over 200#, so I guess I'm technically a clydesdale... I've broken 3 spokes (but no rims) in the past 6 months.

Any idea on why I'm breaking spokes? Too much riding on the Greenbelt?

Clancy said...

Michael, Spoke breakage is usually do to improper spoke tension. Are you replacing them or is a shop? A shop should be checking the tension across all the spokes.

I build wheels but so far only for cruisers and simple builds. No dishing, so spoke tension is easy to figure out with a tensionmeter. I bring Sheldon's page up each time I build a wheel. It is the only time I am allowed to bring the bike tools into the house.

Michael Carpenter said...

Clancy, I'm having a shop replace the spokes. I've never been any good at getting the wheel trued.

Bikeboy said...

Spoke breakage? I'm guessing it's where the "bend" is, at the hub, right?

The way it's been explained to me... usually spokes break because they're are too loose, oddly. (You'd think it would be the other way.) If a spoke or two are looser than the rest, they flex more, and that flex causes a "sawing action" that eventually results in their failure.

I'd probably try a different shop, if you keep having the same problem. A good mechanic at a good shop would probably re-true a wheel for $15, maybe. (But maybe not; it's been awhile since I took a wheel into the shop.)

Michael Carpenter said...

Thanks Bikeboy. Yes, they are breaking at the hub. The shop does it for $15 plus the cost of the spoke. Anyone else have suggestions for a shop?

(Maybe I'm barking up the wrong tree, since you and Clancy seem to have the mad skillz to build your own.)

Bikeboy said...

The best wheel man I know of is supposedly Jason at George's... the one down on Front Street. If he still builds wheels; there was an article in the news a few months back that George's had branched out to doing very precise measurements on riders, and custom-building bikes for them. And Jason might have moved on to that enterprise.

Wheelbuilding is definitely a worthwhile thing to learn about... it's kinda like "The Force" for bikes! If you're committed to cycling for the long haul, and enjoy hands-on, I'd recommend giving it a "go." (Worst-case scenario, you just have to buy a new wheel.)

Clancy said...

I concur about Georges on Front. They have good mechanics and most parts needed.

Ian Laws said...

I'm 52 years, 6' 6" and weigh 210 lbs. I ride a Kona Major Jake for triathlon, century rides and back road cruising. Wheels are Mavic Open Sport/Ultegra Hubs. Should I use 700x23 or 700x25 tires because of my weight? I ride smooth highways and pebbly asphalt country roads. I don't want to change tires for each type of ride. If it matters, I prefer Continental GP 3000/4000 tires.

Thank you
Ian Laws