Classic & Vintage - Mavic Iso-C Rims ?

Back during the late 80's, I lusted for Mavic's ISO-C rims. I remember that they had a equalaterial triangle cross section and were clinchers. I have not seen a set of these rims on any old bikes in this area. Were these rims popular? anyone had them? Why don't they pop up on more late 80's bikes? where are all those late 80's bikes? :P

Iso-C's were a made by Matrix, a Trek house brand. I just sold a set last summer. They were from my '87 Trek 1500.

Back during the late 80's, I lusted for Mavic's ISO-C rims. I remember that they had a equalaterial triangle cross section and were clinchers. I have not seen a set of these rims on any old bikes in this area. Were these rims popular? anyone had them? Why don't they pop up on more late 80's bikes? where are all those late 80's bikes? :P

I have a set of these in 700C clinchers. Mine are the ISO-C, not the the ISO-C II's which may have been an improvement. These rims had their strengths (literally) and weaknesses.

Strengths: The aero profile was very strong. The grey anodizing is pretty hard and lasted a long time before it wore away on the sidewalls. They run true.

Weaknesses: Bad seams caused pulsing braking. These were from before the days of machined sidewalls. The rims must have been pinned together and soldered, but that transition was pretty nasty. Maybe I just didn't put in the miles to break them in but I always had rims I liked better than these. The second weakness is just more of an observation, maybe more superstition or bad technique - more flats than normal. A lot of these were from slow leaks and snakebite punctures. My friend and I both suffered with this. I went through many many tubes and patches in the front on my Specialized hub/Matrix ISO C wheelset. I would check rimtape, tire for debris, tubes, check for metal burrs, monitor tire pressure before each ride. I used to lose like 40 pounds of pressure in one day on that front wheel, its odd, I still to this day don't know the solution but I believe that rim had something to do with it.

If you're going to do a vintage wheel build, I would advise skipping over the Matrix rims, maybe use some modern rims and remove the decals to tone it down a little. My new bike's wheels have DT Swiss RR 1.1's - I like them a lot. Machined sidewalls are much nicer and give much smoother braking.

I have a set of Matrix Iso II tubular rims bought new in the mid to late 80's. They are the same basic design as the clincher rims and yes they don't offer as good a surface for braking and flat sided rims do.
Otherwise they are very strong. I have them on a set of straight skewered NR hubs for my fixie conversion and they just look wrong. Might look better on mid-80's equipped parts and frame. Gerry

Thanks, so they were matrix not mavic, 1987 was a long time ago :) now off to ebay

I bought a replacement NOS ISO II for about $15, not too bad.