Re: Fw: [CR]Bike technology peaked in the 1984? Now Rims

(Example: Component Manufacturers:Avocet)

Date: Sat, 21 Apr 2001 15:36:12 -0700
To: Jerry & Liz Moos <moos@penn.com>, Rick Chasteen <rchasteen@kc.rr.com>
From: "Joseph Bender-Zanoni" <jfbender@umich.edu>
Subject: Re: Fw: [CR]Bike technology peaked in the 1984? Now Rims
Cc: classicrendezvous@bikelist.org
In-Reply-To: <3AE1D101.46CA6B2D@penn.com>
References: <001301c0c9c0$adf82b00$e1bc5e18@kc.rr.com> <3AE197BC.6BF4645F@penn.com> <005d01c0ca8a$6a00aa60$e1bc5e18@kc.rr.com>


There are three factors that probably lead to low rim weight claims: 1) Wear of the extrusion die, with the weights taken from a fresh die, 2) A tradition of discounting the weight of the eyelets, since way back you had to add washers that weren't part of the rim, and 3) Competitive pressure to fib a bit.

I always viewed the Rigida 1320 as a weak rim. The alloy is softer than the period Mavics and the section is very narrow.

Jerry mentioned the Ambrosio Gentleman which has recently been discontinued. I have been very impressed with these rims. They are very round and build easily. The dull silver anodize is not too obtrusive and the labels peel right off. In other words, a great candidate for a classic looking clincher wheelset.

Joe

At 02:27 PM 4/21/01 -0400, Jerry & Liz Moos wrote:
>I think everyone lies a little on rim weight, so it doesn't surprise me that all
>the rims, including the Arc-en-Ciel, which was advertised at 330gm but weighs
>out at 340, are higer than advertised. Of course, a kitchen food scale is not
>exactly a precision scientific instrument, so the absolute weights could be a
>little inaccurate, but the relative weights of rims weighed on the same scale
>should be pretty close. There were some old rims above 500gm, in fact I just
>weighed a Weinmann concave at 550gm, but I don't think the concave was ever
>intended for racing. I'm frankly surprised that the Rigida didn't have a bigger
>weight advantage over the Open Pro. I would have guessed the Rigida was a
>shade under 400gm, but that's why, as someone said earlier in the thread, facts
>are better than opinion. I don't have a non-ceramic Open Pro, but I weighed the
>Open Pro's predecessor, the Open 4 CD, which comes in at 460gm, 10 gm less than
>the Open Pro Ceramic.
>
>I will give the newer rims one thing - they build a very strong front wheel,
>where you don't have the dish of a 10 speed cluster. A year or two ago, I rode
>a metric century on an unfamiliar course. I came around a downhill blind corner
>and hit a big pothole dead center. The impact jarred the handlebars loose in
>the stem, and they rotated downward about 45 deg. After managing to stop the
>bike with suddenly repositioned brake levers, I found that the Open 4 CD front
>wheel was not even knocked out of true. I took out the Allen wrench,
>retightened the bars, and rode on. Don't try that with a Fiamme Ergal.
>
>BTW, if anyone is wondering how to weigh a rim on a kitchen food scale, set the
>scale at the corner of a rectangular kitchen table, diagonal to the angle of the
>corner. You can hang the rim over the scale without it touching the table.
>
>Regards,
>
>Jerry Moos
>
>Rick Chasteen wrote:
>
>> Those weights are a surprise to me! I thought the older rims all weighed in
>> at 500 grams or so since my MA40/MA3/E2's hit that number. That's less than
>> 1 ounce from what you got Jerry, which is scale error or production
>> variance. I'm not surprised about the weight of the Rigida, however, since
>> I had some durability problems with them.
>>
>> For what its worth, the non ceramic Open Pro is supposed to weigh 425 grams.
>> When I get back in town Wednesday, I'll weigh one of mine and post the
>> results to the List.
>>
>> By the way, Listmember Jeremy works at a shop which has a large number of
>> Rigida 1320's in 27" size for a very attractive price.
>>
>> Rick Chasteen, Kansas City
>>
>> ----- Original Message -----
>> From: Jerry & Liz Moos <moos@penn.com>
>> To: Rick Chasteen <rchasteen@kc.rr.com>
>> Cc: <classicrendezvous@bikelist.org>
>> Sent: Saturday, April 21, 2001 9:22 AM
>> Subject: Re: Fw: [CR]Bike technology peaked in the 1984?
>>
>> > Rick Chasteen wrote:
>> >
>> > > Mike, et al:
>> > >
>> > > >>>>>>>If you compare a Super Champion, Rigida, or MA-40 clincher from
>> the
>> > > '70's/'80's, you will find current clinchers are much lighter and
>> > > stronger.>>>>
>> >
>> > I didn't think this was the case, so I pulled some rims out of the attic
>> and
>> > weighed on a kitchen food scale. A modern Mavic Open Pro Ceramic weighs
>> 470gm.
>> > A Mavic MA2 is just slightly heavier at 485 gm. The recently discontinued
>> > Ambrosio Gentlemen, which I think is essentailly the old Super Champion
>> > Gentleman, is 482gm. A Rigida 1320, however, is noticeably lighter at
>> 440gm.
>> > Conclusion, modern clinchers, at least the widely used Open Pro, are about
>> the
>> > same weight as the average old clinchers and heavier than the Rigida,
>> which is
>> > the clincher rim I most commonly see on 70's era bikes set up for racing.
>> Note
>> > that the Rigida I weighed was a 27", so I'd think a 700C Rigida 1320 would
>> be a
>> > little lighter, at least 10gm probably, so for the same size the Rigida
>> would be
>> > about 40gm lighter than the Open Pro. Not a huge difference, but
>> noticeable.
>> > What is a huge difference is that between any modern rim and even a medium
>> weigh
>> > old tubular rim. A Super Champion Arc-en-Ciel, which was not considered a
>> very
>> > light rim in the 70's, weighs 340gm on the same scale, 130gm less than the
>> Open
>> > Pro.
>> >
>> > Regards,
>> >
>> > Jerry Moos