eastbay71

I've spent a good bit of my free time over the last few days searching the internet trying to understand exactly how the Reynolds 653 tube set was made.
I've found this Reynolds Constructor's Guide which lists the dimensions
https://postimg.cc/image/4m8eh9gmt/
And on BF there is this quote from @Scooper;

Reynolds 653 is an odd duck. The stays are 753, but the main frame tubes and fork blades are 531. So, the seat tube is 531 (which is not heat treated), but the seat stays at the seat cluster are 753 which is heat treated.

Copied from another forum FWIW:

Reynolds 653 History

Thanks Jim. Reynolds have sent me a helpful reply so don't spend any more time on this one on my account. I'll tell you what they said as it's interesting and other folk might appreciate it too. In essence, 653 was invented following feedback from Eddy Merckx that a pure 753 frame was too harsh for certain stages. So Reynolds produced a 653 tubeset which combined 753 stays with 531 main tubes and forks. Not any old 531 though, but an even thinner gauge than usual - just for use in the 653 set. Eddy and other riders were very pleased with the result, which combined a light, ultra-stiff and efficient transmission with a more forgiving and comfy ride. Nowadays when folks are after a similar ride builders use 725 stays and usually 631 for all other tubes. I heard it from the horse's mouth.

"Cold drawn" has nothing to do with whether the tubes are heat treated or not; it's simply the term used to describe drawing the tubing through dies and piercing with mandrels to get the tubing to the specified wall thickness and butting.

So this got me thinking. Given Reynolds 753 is made from the same alloy as 531 that is then drawn thinner and heat treated and the 653 main tubes are made from 531 that has been drawn thinner but not heat treated. And the dimensions of the tubes in a 753 set are the same as the tubes in a 653 set. Isn't this the same as saying that 653 is just a 753 tube set where the main tubes have not heat treated? Am I off base on this one?

For some reson there is very little definitive information on Reynolds 653 anywhere online.

I also wonder if the Eddy Merckx connection is real or legend given Eddy retired in 1977 and Reynolds 653 hit the market a full 10 years later around 1987. Unless he was concerned about other racers that bought his frames.

Kilroy1988 

I hadn't looked into 653 previously, but based on the information you just provided that sounds about right. I would suggest that the drawn out 531 used for the main triangle would not have been as slender as 753, because if it was then 753 could have been made without heat treatment being necessary to maintain rigidity.

TenGrainBread 

Yes. Although I don't think you could say for certain that they are the same gage. If that were true then it would be pretty silly to mix the tubing based on a complaint about 753 being too stiff, as two steel tubes with the same gages will be equally stiff. So they are probably not the same thickness.

eastbay71

Here is the chart giving their internal dimensions


Is that the same as guage?

eastbay71

Just to add to my being skeptacle of this origin story of 653 not only did it come out long after he finished racing, I've also not been able to find a single example of an Eddy Merckx frame made from 653. When he used Reynolds he used 531 and 753 he also used Columbus tubing of various grades.

Spaghetti Legs 

Here's my '89 Century in 653. However they make it, it's a nice riding machine.



This was the first and I believe only year in Reynolds for this, then they went to TSX. Here's a link to the catalog.

Eddy Merckx catalog (1989)

Kilroy1988 

The tube guide posted above show that the main triangle tubes are in fact of equal gauge to the 753 tubes. Interesting. So essentially it's just as you suggested, @eastbay71. 653 is essentially 753 without heat treated main tubes.

eastbay71

Awesome! A rare bird indeed!

T-Mar

Not quite correct, but close. According to a 1988 Bicycling article;

"Reynolds 653 is a composite tubeset that uses 531 forks for shock dampening and a 531 main triangle that's slightly work hardened to increase it's strength. The rear triangle is heat treated, but to a lesser hardness than 753, The result is a tubeset that costs the builder about 1/2 as much as 753 and can be brass-brazed."

The reason for referring to the main tubes as being 531 based are because 531SL used these tube gauges long before 753. When originally introduced, 753 was only available in metric sizes and used a thinner (28 gauge/0.35 mm) centre section. The tubing thickness in the above chart in post #4 are for the revised, imperial sized 753R tubesets introduced circa 1983-1984. The R suffix was dropped later in the 1980s.

himespau 

interesting

eastbay71

Thanks for that @T-Mar! The blurry picture that is the 653 story comes a bit more into focus. I had heard that main tubes were more based on 531SL but couldn't find any technical documentation for the SL tubes.

Scooper

There certainly is a lot of confusion about 653. This page about decal history downloaded from the Reynolds website says 653 has 531 main tubes drawn thinner than 531C, and with 725 rear stays.

Reynolds Decal History | reynoldstechnology.biz (pdf file)



725 is heat treated seamless 25 CrMo 4, which has chemistry virtually identical to 4130.

ThermionicScott 

I don't know what difference it makes that he was no longer racing. It's not like he stopped riding or anything.

T-Mar

Here you go! Note that 21 gauge = 0.8mm, 22 gauge = 0.7mm & 24 gauge = 0.5mm. Also note the reference to it being thinner than 531 but not as thin as 753. Introduced in 1975, it is immediately recognized by a red coloured "531" on the tubing label, as opposed to the standard green. IIRC, it was used on Thevenet's TDF winning Peugeot PY10 in 1975 & 1977.

eastbay71

More great information @Scooper. You are one of the most knowlegable guys I've seen on Reynolds. Someone was trying to tell me that 753 was thinner because they used vanadium in the alloy. Is there any truth in that? Did Reynolds use vanadium in any of their alloys? I've never seen it listed on a chemical composition sheet but couldn't find the composition of 753.

T-Mar

My main problem with this description is that 725 didn't even exist when 653 came out, so how could 653 use 725 stays?

Kilroy1988 

I'm going to guess that's a typo which was meant to reference 753.

eastbay71

I just didn't think he would have as much influence. And the way the story has been repeated it was like he had complained about 753 and Reynolds made a new formula for him to use on the cobble sections of the Tour de France. I also thought it was odd that Reynolds would go through the trouble and then Eddy never used it. But I was proven wrong on that account. He did use it in '89

Scooper

I can only guess that 753 may have been used initially with 725 substituted later, and that Reynolds didn't change the tubeset designation.

eastbay71

Where do you find this stuff? Do you have the catalogs?

Scooper

I've had really good luck emailing directly to Reynolds, Terry Bill before he retired and now Keith Noronha, to get answers to historical questions about Reynolds tubesets. I just emailed Keith about 653, and if he responds it'll probably be next week.

eastbay71

Thanks! I decided a couple years ago to try to get a nice example of each of the more popular grades made by Reynolds. Mostly driven by the amount of bad information on internet forums. I have a 531C Trek, a 753R Gazelle, one of the early Specialized AWOLs made of 725 and an 853 Schwinn that are riders. I've also owned but sold 502 and 531ST Treks. I'll be building out a 653 frame this winter and wanted to know more about it. I haven't gotten a 953 bike yet. Still too expensive for me. This thread has been enlightening!

bikinbruce

Hello,
I am trying to determine the approximate timeframe of when my Australian Soren Son frame was built.
My frame does have 126mm rear spacing but because of the outrageous prices of components in Oz that may not be a good indicator of the true age. The original owner could have moved parts from a previous bike. I don't think it is any later than '93 because I have seen photos of other frames by the builder made in '94 with straight blade forks & mine has curved fork blades.
So if anyone knows the years of tubing production that might help narrow it down.
Thanks,
Bruce

Scooper

The chemistry of 753 is identical to 531. 753 has higher ultimate tensile strength and yield strength than 531 because of the heat treating, and because it is stronger it can be drawn with thinner walls. The thinner walls make 753 flexier than 531, but OS tube diameters restore stiffness lost because of the thinner walls. As you can see, there's no vanadium.





This chart shows the chemistry of more recent Reynolds steel tubing. No vanadium.

Scooper

As usual, Keith Noronha, Managing Director of Reynolds Technology, responded quickly to my email. I am indebted to him for all of the times he has answered my sometimes stupid questions.