TallRider

I'm curious as to the typical weight of single-wall 27" (aluminum) rims that were very common on road bikes from the early-80's and prior. Commonly made by Araya, Weinmann. still available some places. Usually 36-hole, though sometimes manufactured with 40 or 48 holes.
The only weight I've been able to find is 628g for the Alex X404. I'm guessing weights don't vary a ton for these sorts of rims, because construction methods are usually the same. Here's the view of the Alex rim, others are similar but often without the curve in the spoke bed.


There are other 27" single-wall rims currently on the market (e.g., Harris sells the Weinmann RM19) but I've not been able to find weight info for them.
I'd appreciate any input, even if it's memory fragments some of you have sitting around in your brains. Thanks.

Seggybop

bumpage for infos

TallRider

I've found a few other weights.
First, the Velocity Twin Hollow rim is listed on Velocity's website at 540g.
More impressively, I've got a NOS Araya rim of this same construction/design, and took it to the post office today and weighed it a couple of times. Came out at 488g both times.
So, I'm definitely not going to buy the Alex rims at 628g, even though they are low-price.

DannoXYZ 

Wow, that's almost 3/4 of a lb from just the two rims alone! You should also be aware of strength differences though; I'm sure the Alex are stronger. Why single-section rims?

HillRider

I don't have any data to add to this thread but I recently bought the first single wall rim I've had in almost 20 years.

I bought a Nashbar "house-brand" rear wheel (the rim label says Cyclepro) with an Alex single wall 700c rim, 14 ga stainless spokes and a 32 hole Shimano 2200 8/9-speed hub laced 3x for the grand total of $35. I needed a replacement wheel for my '83 vintage Trek rain bike and money was definitely an object. It came quite true and the spoke tension was pretty much right on so the build quality was better than I expected.

This thing is certainly not light but for my purpose it is perfect since the conditions it is being used in will wear out the rim fairly quickly and stronger is better.

TallRider

That's interesting to put it in perspective of how much rotating weight is saved (actually 0.61 lb.)
The Alex may be stronger, but I'm guessing that not all of their extra weight goes toward more strength - I suspect they also are heavier so they can work with lower quality control and sell a low-cost rim for people who want such a thing. QPB has the Alex rim for $12.

Single-wall rims largely for cost, but also for similar E.R.D. so I can reuse the spokes. I'm rebuilding some wheels with new rims recently, and the spokes are in good shape (one rim is just slightly taco'd, while the other wheels have steel rims but nice hubs and butted spokes).
Also, I'm not too worried about a single-wall rim on a well-built wheel with 36 spokes, especially for front wheels and a rear wheel with 132.5mm spacing (to go on my mom's touring bike, and replace the 126mm-spaced freewheel-hubbed rear wheel that she has, also with single-wall rims).

To my knowledge, single-wall rims aren't necessarily weaker than double-wall rims without double eyelets; the double-wall rims can usually be a bit lighter is all.

That said, I've got a 36-hole 7-speed-cassette 105 hub hub, 126mm spacing, and I'm going to build it up with a 27" Sun CR18 rim (double wall, single eyelet, pretty nice and durable rim) for use on one of my huge old Schwinn frames designed for 27" wheels.

HillRider

Before you do the 27" rim build, see if the brake blocks will lower the 4 mm needed to align with 700c rims. I've done this successfully with an early '80's Trek frame and a mid-80's Bridgestone, both of which came with 27" wheels and now have 700c wheels. If the 700c rims will work, your rim choice goes way up and you can simplify your tire inventory.

TallRider

Good point HillRider. It doesn't look as if either of my Schwinns will take this, nor will my Miyata. So I'm finishing off the build with the 27" Araya rim and 7-speed, 126mm-spaced freehub.

Another weight update: I took a Sun Mistral rim (single-wall twin hollow, 36-hole, 27", hard-anodized, with eyelets - obviously single eyelets) to the post office today, and it weighed in at 1 lb. 2.2 oz. That's 516g.

froze

My old 27" Weinmans were tubular and they weighed about 400 grms whereas my old 27" Mavic clinchers weighed about 445 if my memory serves me correctly, these weights are just bare rims. These were all 36 hole rims. There isn't a whole lot of weight difference between 27 and 700's; my current 700 Torelli Master Series clinchers weigh 425 and you can get 700 tubulars that weigh 375; so it appears that your only saving an average of 30grms going to 700...BUT problem today is finding good lightweight 27" rims, thus you may not be able to find the lightweight racing 27" rims that were available back in the late 70s's and early 80's like I used; therefore a 27" rim will probably weigh far more then an average 700 rim today.

HillRider

Tim, You're at UNC in Chapel Hill right? Make friends with someone in any of the science or engineering departments. They will have access to a wide range of lab scales and should be able to weigh almost anything you want, up to and including a frame!

TallRider

Good thoughts. I've got friends in compsci and physics, which should suffice.
What I've usually done for weighing frames is weigh myself on a good scale, then weigh myself with the frame. Multiple trials each way, then calculate the difference. But a specialized scale would be nicer for this.

rmfnla

Back when we used 27" wheels we were so glad just to find aluminum rims instead of steel we didn't really question the weight. By the time we were counting grams we had moved on to 700c and never looked back.

Good luck with your Schwinn!