Originally Posted by
ericthered
Boy, how do you respond to some with over 12,000 post.
I was referring to my 32mm tire (which is my primary rear tire size but once again NOTHING UNDER 28mm) when I said that they were at 85 psi which seems in line with what Sheldon would recommend (he actually says 75).
http://sheldonbrown.com/tires.html
Tire width in mm
Wheel load 50 mm 37 mm 32 mm 28 mm 25 mm 23 mm 20 mm
100 lbs/50 kg 45 60 75 100 110 120 130
70 lbs/35 kg 35 50 65 80 90 100 110
What you missed in Sheldon's discussion is this
The table below is based on my experience and a certain amount of guesswork, and should only be used as a very rough guide to a starting point. Interpolate/extrapolate for your own weight/tire sizes.
For example: Even as a heavyweight rider, I'd wouldn't run a tire at 130psi like Sheldon suggests for 20mm wide tires. I'd actually tighten up the pressure range on all the tires. For example, I'd run a 37mm tire at around 80 psi and a 20mm tire around 115 to 120 psi. A 37mm tire is a 1.5" tire which, in the grand scheme of things isn't all that wide. On a mountain bike, I run 2.2" (55mm) tires at 45 psi in off-road situations but that's because there's a balance between rim protection and pinch flats. I also ride much, much lighter off-road...even with full suspension.
Originally Posted by
ericthered
The two comments that you glossed over were why I liked A719. 1) eyelets 2) wider.
There is also differences in rim materials that will make them more or less resistant to denting when subject to abuse. You can see this in discussion on mnt bike forum. Honestly, I cannot always dodge that pothole, railroad track, etc and un-weight as well as I would like in TRAFFIC. My current mavic a719 and previous alex dv15 did not dent in the same way as I experienced with the "bombproof" deep V.
Eyelets make very little difference. They are nice but not totally necessary. I've built dozens of wheels with and without them. I've never noticed a differences in longevity.
Width also means little. I ride mountain bike wheels with the above 2.2" tires on 17mm wide rims. A wider rim is just heavier. It's not necessarily stronger.
The only rim material that would be more resistant to denting is a steel rim. Aluminum is basically aluminum. All the different alloys have about the same properties and about the same strengths...within a rather narrow range. But I wouldn't use a steel rim for several reasons including weight and poor wet weather braking.
I think you missed my point on road hazards. You don't have to dodge all of them...although you should dodge what you can. If you can't dodge them,
can unweight even in traffic. All that takes is you standing up on the pedals. You can even hop the bike over stuff or, at the very least, lift the rear wheel so it doesn't slam into the obstacle as hard. Unweighting the bike and letting your body absorb the shocks even improves your control.
Originally Posted by
ericthered
I hold by my statement that I think the mavic a719 are a stronger rim and prefer them over the deep V. The $25 difference is cheap on the front end and I have plenty of places to lighten the bike above the saddle. I guess the real difference can be seen on Peter White's site. The Deep V is under "Racing" while the A719 is under "Touring". If you are looking for the strongest "narrow racing" rim, deep V, "My strongest narrow rim for racing. 30mm tall." My guess is that any of the rims in Touring are "stronger" than the deep V. The a719 might also be easier to build with the access to the nipples and eyelets over the deep V for a novice (considering OP).
Cheers
Eric
As I've said in numerous locations on this forum, strength of the wheel doesn't lie in the rim. The rim is a convenient place to attach a tire. The strength of the wheel is in the spokes. Your problem and comment, i.e. that you "dented" a rim, has little to do with wheel strength anyway. Strength is a longevity issue. Denting a rim is an operational issue. You build a strong wheel by choosing, in order, good spokes, a good hub and (a distant 3rd) rims. You maintain a good wheel by choosing proper tires and inflating them so as to keep the rims from being dented.