Raleigh Dyna-Tech Pro

[ferrus]

I believe there was no direct equivalent conventionally numbered (3figure) Reynolds tubeset for any of the bonded tubesets. The higher spec tubes on conventional frames are thinner gauges so the hole through them is larger but on the bonded frames lugs were internally sleeved into the tubes and common to all the frames so the internal dimensions of any tube in a specific position had to be common regardless of the ‘poshness’ of the tubeset. Take that little problem and add in the fact that brazing or soldering a frame affects the finished strength of the tube there was not much point trying to manufacture sets that exactly matched Reynolds conventional tubes.

Yeah I agree with this. The Dynatech bonding process negated the need for butting as the tubes wouldn’t be suffering any strength loss through brazing.
I used to own a Pro but I got run over and the frame was snapped beyond repair! Interested to see how it was put together, I cut up the downtube; there was no evidence of conventional butting - it was super thin end to end…

 

[3wheeler7]

According to Raleigh the Dynatech 2080 main frame tubes were butted.

 

[peetee]

According to Raleigh the Dynatech 2080 main frame tubes were butted.

I’d be interested to know what the internal dimensions were. The lugs must have created a compromise for some of the tubes used. Either the lower strength tubes were too thin or the upper grade were excessively thick. The former would be A Bad Thing for any customer and commercial suicide for the brand as that would be the bulk of production. So it’s likely the stronger tubes were still butted to reduce unnecessary metal in the centre sections. It’s just the gauge of the tubes didn’t match those of the standard tubesets. Looking at things from the commercial side again, it’s much better for a ‘new technology’ product to have a complete makeover in branding. Raleigh called it Dyna-Tech and added new frame tube decals rather than the old standards of 501, 531etc. The Reynolds name was still there - I’d guess that was enough to add the ‘nothing-but-the-best’ element.

 

[peetee]

I’d be interested to know what the internal dimensions were. The lugs must have created a compromise for some of the tubes used. Either the lower strength tubes were too thin or the upper grade were excessively thick. The former would be A Bad Thing for any customer and commercial suicide for the brand as that would be the bulk of production. So it’s likely the stronger tubes were still butted to reduce unnecessary metal in the centre sections. It’s just the gauge of the tubes didn’t match those of the standard tubesets. Looking at things from the commercial side again, it’s much better for a ‘new technology’ product to have a complete makeover in branding. Raleigh called it Dyna-Tech and added new frame tube decals rather than the old standards of 501, 531etc. The Reynolds name was still there - I’d guess that was enough to add the ‘nothing-but-the-best’ element.

When you look at the numbering for the traditional Reynolds tubes there is some logic. The higher spec have higher numbers. The same with the Dyna-Tech Reynolds numbering. The curious thing is that the sets are broadly comparable in strength; bonded to brazed. As discussed previously the bonded tubes retain their strength while brazed loose a bit. The numbering reflects this in a way.
531 strength tubes became 2060 (5 ‘series’ become ‘60’.
653 became 2070 (6 ‘series‘ becomes ‘70’)
753 became 2080.
That might seem a bit tenuous and might not have been intentional but it’s how I remember where a particular model sat in the range.

 

[ferrus]

I still have that downtube somewhere, but pretty sure the headtube end has been chopped off to tidy it up as it was so mangled. If I can find it I’ll get a micrometer on the BB side. Both ends were really thin, as mentioned.

 

[Gtpulse]

You can see the top of the seat tube looking down in to the lug casting. It’s pretty thin….

 

[ferrus]

Doesn’t look like it could go much thinner does it, I can’t see how there’s any butting there.

 

[peetee]

Doesn’t look like it could go much thinner does it, I can’t see how there’s any butting there.

On a normal lightweight frame the top of the seat tube isn’t butted. It has to be plain gauge because the tube is trimmed to match the frame size and has to allow the seat post firm purchase regardless of its length.

 

[vcballbat]

On a normal lightweight frame the top of the seat tube isn’t butted. It has to be plain gauge because the tube is trimmed to match the frame size and has to allow the seat post firm purchase regardless of its length.

Just like to add on a normal steel frame the top of the seat tube is split to be part of the clamping, on the DynaTech the cast aluminium seat lug performs the clamping, could there be a steel shim?

 

[ferrus]

On a normal lightweight frame the top of the seat tube isn’t butted. It has to be plain gauge because the tube is trimmed to match the frame size and has to allow the seat post firm purchase regardless of its length.

Of course, yes. I was having a bit of a senior moment there!
The tube is incredibly fine; I’ve never seen a seat tube as thin as that before. To be honest I think my down tube was slightly thicker on the ends than that so was possibly butted after all then.