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scozim

I've always been intrigued with the published weights of bikes by the manufacturers and reality. I know there are a whole lot of variables involved but I decided to do an unscientific test with my bikes today and a bathroom scale.

The 1984 Sprint is advertised in the catalog at 23.8 lbs. Mine is a 52 cm with all original components except for the tires (700X25), Selle Italia SLR gel flow saddle and older Scott aero bars for the trainer. The approximate weight came in at approximately 23 lbs so take away the aero bars and it'll be down around 22lbs.

The Tour de France is all original with the exception of a Selle Italia Mundialita saddle, Suntour Blue Line derailleurs and a Regina Super Leggerra alloy 13-26 freewheel Advertised weight in the catalog for a 54 cm (what I have) was 22 lbs and mine came in right around 20 lbs - which surprised the heck out of me.

Yes, components make a big difference but I think the parts on mine aren't enough because the real weight savings could be in the wheels, fork and other parts vs. an aero bar or some derailleurs.

I had always suspected manufacturers overstated the weights a little and I don't know that this prooves it.

For what it's worth I'll definitely be riding the lightweight TdF a lot this summer when fighting the wind.

verktyg

Ideally bike manufacturers would have chosen a middle frame size bike like a 57cm or 58cm for their advertised specs. In reality, they frequently listed the weight for a 50cm or 54cm size bike.

The 1970 Gitane brochure listed weights as follows:

Interclub at 24 1/2 Lbs.

TdF at 21 1/2 Lbs.

Super Corsa at 22 Lbs.

The TdF components were lighter plus the SC had an Ideale Leather saddle.

It appears that they didn't list weights in their catalogs again until the 1980s. In the 1984 catalog Gitane lists weights for 57cm frames:

http://www.gitaneusa.com/images/catalog/1984/Page_02-b.jpg

During the Bike Boom era manufactures frequently ran shout of components and substituted what ever they could get. This also applied to frame parts too.

My first Super Corsa was a 60cm and weighed under 21 Lbs. with an Ideale 90 leather saddle, sewups and all Campy components except for Mafac Competition brakes. I switched the rims and tires to 27" clinchers and it still weighed about 23 Lbs.

I suspect that this bike had a frame made of extra light gage Reynolds 531 tubing. Either that or they used a seat tube for the down tube! Rolling Eyes

It was so latterly flexible across the bottom bracket that I could move it side to side about 2" in a hard sprint. It frequently "ghost shifted" by itself when climbing up a hill.

The frame was too big for me and I was able trade it (plus $100) for a 57cm frame. The smaller frame weighed over a pound more but it was much less "whippy".

Reynolds produced 531 butted main tubes with wall thicknesses from 0.7mm\0.5mm to 1.2mm\0.9mm. Many production bikes were usually built with heavier gage main tubes such 1.0mm\0.7mm wall thickness.

The heavier tubes could be brazed by less experienced workers.

Gitane performance frames from the 1980s used much thinner wall thickness tubing such as Super Vitus, 971 and 983, Columbus SL and Reynolds 531c and 531 Professional. These made for lighter weight bikes.

Advances in clincher rim and tire technology has resulted in wheels that ore close to sewups in weight.

So the bottom line is that you can't always judge a bikes ride or performance by the advertised or real weight.

Chas.