Stan's ZTR Alpha 340 rims question

Triathlon Forum
1

I’m a 135 lbs road rider (125 lbs during the summer). Mostly recreational riding…with 2-5 races a year (road or crit). I have a set of Circus Monkey hubs(20h/24h). I’m thinking of using them to build up a set of ZTR Alpha 340’s. I’ll be using them as standard clinchers, not tubeless.

A couple questions…

  1. What’s the narrowest and widest tire I can safely use on this rim?

  2. Will this rim built up 20/24 with Sapim CX-Ray spokes be sturdy enough for my weight and intended use?

  3. I’ve read a couple threads about an unusually high amount of spoke detensioning after you mount and inflate tires. Is this a real issue? How can it be avoided?

Thanks!!!

2
  1. As narrow or as wide as you’d like (within reason). I’ve put 22c tires on mine and 35c tires on my cross bike.
  2. Absolutely. I race at 165-170lbs and used 24/24 for cyclocross
  3. Hire a good wheel builder and it won’t be an issue.
3

One thing to think of is that Stan’s rims are not eyeletted. I’m not a wheelbuilder but a 20 spoke wheel on a non-eyeletted rim might be a problem. I use Stan’s rims on both my mountain bikes and have never had a problem but all the wheels are 32 spoke.

4
  1. As narrow or as wide as you’d like (within reason). I’ve put 22c tires on mine and 35c tires on my cross bike.
  2. Absolutely. I race at 165-170lbs and used 24/24 for cyclocross
  3. Hire a good wheel builder and it won’t be an issue.

and i have a friend who’s 160# and broke spokes on his 28/32 build…

To the op, it’s more about the power you generate

350g alloy clincher is just “too light” in my books.

As for the 3rd concern, don’t worry about it. The tension specs is before inflating a tire. That said, retentioning and some truing will be necessary once you get 500-600 miles on your wheels. The wheel will still be mostly true, but the tension, even with stress-relieving, will be off quite a bit.

5

  1. You can use anything between 18 and 60mm. The fastest tire is probably the 20mm Conti Supersonic… makes a good aero shape with the rim.

  2. I’ve been riding a similar set that is 18f and 24r… and I weigh 175 lbs. Must be ~8k miles now and no truing needed. Power output doesn’t matter… what matters is weight and riding style. Unless you tend to break things you should be fine.

  3. Don’t worry about it… just do your final truing with the tries on and inflated. Go for 100-110 kg on the DS rear.

Are you building these yourself? Do you know what you are doing?