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Weight difference between 2030 and 531 frames

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Old 05-03-22, 07:37 AM
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swampyankee2
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Weight difference between 2030 and 531 frames

I've read alot about how much better a 531 frame is to a lower end 2030 frame, but what is the weight difference? Had anyone weighed a frame from, say, a Super Course against the same era and size Grand Prix? What kind of weight savings are we talking about here?
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Old 05-03-22, 08:12 AM
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The 1971 Raleigh catalog shows just a one-pound difference between the two:

https://www.kurtkaminer.com/1971rale...t_us_04_lg.jpg
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Old 05-03-22, 08:19 AM
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Originally Posted by nlerner
The 1971 Raleigh catalog shows just a one-pound difference between the two:

https://www.kurtkaminer.com/1971rale...t_us_04_lg.jpg
Good reference. Some of that weight diff could be due to other hardware, such as alloy rims vs steel.
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Old 05-03-22, 09:36 AM
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I asked myself the same thing a few months ago

https://www.bikeforums.net/classic-v...e-weights.html


I've had several Raleigh frames hanging in my shop waiting to be built up so while cleaning up, thought I'd weigh them to see if there were any significant differences between the Grand Prix, Super Grand Prix and the Super Course.

All three frames are 23-1/2", the Grand Prix and Super Course are 1972 models. The Super Grand Prix is from 1977

Both the Grand Prix and Super Grand Prix have 2030 "High Tensile" tubing throughout. The Super Course has Reynolds 531 Straight Gauge frame tubes and "High Tensile" fork blades and rear stays

The weights are as follows:

Grand Prix
Frame: 2648 grams
Fork: 862 grams

Super Grand Prix
Frame: 2706 grams
Fork: 852 grams

Super Course:
Frame: 2538 grams
Fork: 834 grams

The Grand Prix and Super Course have identical frame geometries so the weight differences are attributed to the tubing types, not sure why the forks have different weights

The Super Grand Prix, although the tubing is the same as the Grand Prix, the frame geometries and designs are completely different. The SGP is designed for 700C wheels, has a shorter wheel base and much beefier seat stays, it is more of a racing geometry than the Grand Prix. I've restored a couple of Super Grand Pix's and they were a stiffer and more responsive ride than the GP's I've ridden.
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Old 05-04-22, 08:59 AM
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you're welcome
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Old 05-04-22, 10:23 AM
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Originally Posted by branko_76
you're welcome
Yes, thanx for the info. I had unwittingly been replying to the thread that was linked instead of this one.
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Old 05-04-22, 03:47 PM
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The big difference is from plain gauge steel to double-butted, and it's not the weight weight that the makes the difference. I don't know how to describe the difference, but it's there. OTOH, I suspect you can make a Grand Prix right ride closer to a full DB frame by riding on light, well-made tubular wheels and sewups. Of course, you may spend more on tires and more time on fixing flats and sewing with sewups....

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Old 05-04-22, 05:02 PM
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Originally Posted by branko_76
I asked myself the same thing a few months ago

https://www.bikeforums.net/classic-v...e-weights.html


I've had several Raleigh frames hanging in my shop waiting to be built up so while cleaning up, thought I'd weigh them to see if there were any significant differences between the Grand Prix, Super Grand Prix and the Super Course.

All three frames are 23-1/2", the Grand Prix and Super Course are 1972 models. The Super Grand Prix is from 1977

Both the Grand Prix and Super Grand Prix have 2030 "High Tensile" tubing throughout. The Super Course has Reynolds 531 Straight Gauge frame tubes and "High Tensile" fork blades and rear stays

The weights are as follows:

Grand Prix
Frame: 2648 grams
Fork: 862 grams

Super Grand Prix
Frame: 2706 grams
Fork: 852 grams

Super Course:
Frame: 2538 grams
Fork: 834 grams

The Grand Prix and Super Course have identical frame geometries so the weight differences are attributed to the tubing types, not sure why the forks have different weights

The Super Grand Prix, although the tubing is the same as the Grand Prix, the frame geometries and designs are completely different. The SGP is designed for 700C wheels, has a shorter wheel base and much beefier seat stays, it is more of a racing geometry than the Grand Prix. I've restored a couple of Super Grand Pix's and they were a stiffer and more responsive ride than the GP's I've ridden.
So the density of 531 and 2030 are the same, so if a 531 frame with the same tube lengths and diameters tub3 for tubehas lower mass, it must have thinner tubing walls compared to the GP, made of thicker 2030. This is a reasonable design choice, because 531 is a stronger alloy than 2030. If you make two dimensionally identical frames intended to last the same length of time with the same level of usage, the 531 frame will be lighter, and a little more supple. Built to the same product usage goals, i.e. the same patterns of stress, the 531 frame should be lighter and perhaps more comfortable.

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Old 05-04-22, 05:29 PM
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Originally Posted by Road Fan
So the density of 531 and 2030 are the same, so if a 531 frame has lower mass, it must have thinner tubing walls compared to the GP. This is reasonable because 531 is a stronger alloy than 2030, so if you make identical frames out of one and the other and aim for the same durability, you can have less weight in the 531 frame without the risk that your frame is going to fracture.

this is with all tube lengths and ODs the same tube for tube, but the wall-thicknesses are reduced for the 531 tubes. This also allows the 531 tubes to hav a little more flexibles, a little more supple ride quality.
Yes, same o.d. but the 2030 frame takes a 25.4 mm seat post and the 531 accepts a 26.4 mm seat post
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Old 05-04-22, 06:34 PM
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Originally Posted by branko_76
Yes, same o.d. but the 2030 frame takes a 25.4 mm seat post and the 531 accepts a 26.4 mm seat post
Yes, so that demonstrates the thicker walls to be found on the 2030 frames. The seat post wall Is a little thicker than for the 2030, but I bet the net mass reduction sstill goes to the 531 tubes.

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Old 05-05-22, 07:26 AM
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Granted this doesn't have everything- but you get an idea of how much a tube set weighs- roughly between 1600 and 3200 grams. There's probably also much heavier tubing than listed here.

As someone who bolts racks, loads up water bottles, connects bags filled with junk onto my bike... that weight is negligible. However, to someone counting those grams it's significant.

The other point is the thickness of the tubes make a difference in the compliance of the ride. It's not just the sheer mass, it's the way the tubes respond- and that's partially due to the mass and hardness of the tubing... I'm probably using the wrong engineering terminology.

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Old 05-05-22, 11:36 AM
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I certainly don’t know much about it, but I think the magic is in the tubing. Some/most of my bikes were also purchased to experience the different tubings. I am an old slow rider, but can sometimes enjoy the difference. As stated, all the other peripherals contribute greatly.

I bet others can chime in on more than just the weight being important. Golf club shafts, fishing rods, musical instruments and many others I would bet show the differences of the higher end tubing.
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Old 05-05-22, 12:15 PM
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Originally Posted by The Golden Boy
Granted this doesn't have everything- but you get an idea of how much a tube set weighs- roughly between 1600 and 3200 grams. There's probably also much heavier tubing than listed here.

As someone who bolts racks, loads up water bottles, connects bags filled with junk onto my bike... that weight is negligible. However, to someone counting those grams it's significant.

The other point is the thickness of the tubes make a difference in the compliance of the ride. It's not just the sheer mass, it's the way the tubes respond- and that's partially due to the mass and hardness of the tubing... I'm probably using the wrong engineering terminology.
This, yes. I am no expert, but I know that master framebuilders use different tubes for different parts of each frame based on the expected riding behavior of the customer, and they base this on what they know about the characteristics of the tube design and how they're mated together. I know I'm not responding to what the OP asked, but if OP is wondering about weight differences in a "what's the point" kind of way, then this is a good, albeit vague, response to that.
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Old 05-05-22, 12:23 PM
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Thanx for all the replies and info. To sum it up, of my 3 vintage bikes, one is a 531 frame Dawes, the others are standard Raleigh Hi-ten - a Sports and a 10 speed Robin Hood Lenton Sports. The Lenton Sports has chrome steel drop bars and stem, and steel fenders so the extra frame weight isn't a factor. For what it's worth, it does have a very comfortable ride and a good enough turn of speed for an old duffer like me. But the Dawes is my poor man's Super Course, although I'm not sure I'm conditioned enough to notice the advantage of it being 531 framed.

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Old 05-05-22, 02:05 PM
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Originally Posted by The Golden Boy
Granted this doesn't have everything- but you get an idea of how much a tube set weighs- roughly between 1600 and 3200 grams. There's probably also much heavier tubing than listed here.

As someone who bolts racks, loads up water bottles, connects bags filled with junk onto my bike... that weight is negligible. However, to someone counting those grams it's significant.

The other point is the thickness of the tubes make a difference in the compliance of the ride. It's not just the sheer mass, it's the way the tubes respond- and that's partially due to the mass and hardness of the tubing... I'm probably using the wrong engineering terminology.
Hardness has zero to do with ride. All, and I mean all steels have pretty much the same modulus of elasticity - the measurement of "springiness" of the material. All other things being equal, increase in diameter and/or wall thickness increases stiffness of the frame.
@Doug Fattic posted somewhere here awhile back about frame weight being somewhat helpful in guesstimating what tubing wall thickness was used. It was a great explanation, if I could find it I'd provide a link.

If one had a set of 2030 tubing made up dimensionally the same as a 531 double butted set and made a frame, theoretically they'd ride exactly the same. The difference would be the strength of the frame - the 2030 frame needs more material for the same strength.

The ASFE* has promoted the idea that steel frame tubing can be made stiffer and lighter.

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Old 05-05-22, 02:32 PM
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Originally Posted by swampyankee2
But the Dawes is my poor man's Super Course
That's an interesting thought. It might just be the other way around.

Anyway, I have 25" examples of both in my project queue, and hope to be able to build up at least one of them this summer. One day I'll be able to actually compare them.

The crusty Super Course:




The dilapidated Dawes Galaxy:

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Old 05-05-22, 02:55 PM
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Originally Posted by noobinsf
This, yes. I am no expert, but I know that master framebuilders use different tubes for different parts of each frame based on the expected riding behavior of the customer, and they base this on what they know about the characteristics of the tube design and how they're mated together. I know I'm not responding to what the OP asked, but if OP is wondering about weight differences in a "what's the point" kind of way, then this is a good, albeit vague, response to that.
Ultimately it's about stiffness vs weight to achieve a desired strength/durability, not hardness. Thinner tube walls are lighter, more flexy, and more responsive to absorb shock and to pedaling efforts. The price is that if the strength (resistance to breakage) is not improved, the frame might not last as long and dent or break more easily. Hence with 531 or Columbus (or Ishi, Tange, TruTemper OX, et cetera, the more exotic, more processed, stronger types of steel are more expensive and sometimes more expensive to cut, file, and otherwise work.

So lighter, more supple frames with good durability are inherently more expensive due to time, materials, and labor, sometimes special tools. For the bicycle (frames plus parts kit) cost is based on the frame and the fact that a higher-end frame justifies the cost of higher end parts. The bicycle upcharge is due to teh frame AND the parts.
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Old 05-05-22, 03:10 PM
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Originally Posted by non-fixie
That's an interesting thought. It might just be the other way around.
Hah! Searching for my first vintage 10 speed, I was enamoured by an early Super Course for $300, but found a slightly rougher Galaxy for $70 and closer by. Hence, my Dawes was my poor man's alternative. And I've learned alot while bringing maintenance up to date and upgrading stuff.
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Old 05-05-22, 03:15 PM
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Originally Posted by swampyankee2
Hah! Searching for my first vintage 10 speed, I was enamoured by an early Super Course for $300, but found a slightly rougher Galaxy for $70 and closer by. Hence, my Dawes was my poor man's alternative. And I've learned alot while bringing maintenance up to date and upgrading stuff.
I have three different straight guage frames... 2 Reynolds and one generic chromoly. They all feel great.
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Old 05-06-22, 06:49 AM
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The difference in frame weight is easy to calculate if we make some assumptions:

1. The gauge used in the top and down tubes are the same as the seat tube.
2. The density of 2030 and 531 is the same.
3. Fork, stay and head tube material is the same.
4. Frame fittings are the same.
5. Geometry is the same.

Assumptions 3,4 and 5 reduces the difference to a comparison of the main tubes. At that point it comes down to an easy calculation of the volumes based on measurements of the frame tubes and applying the steel density.

I did this excercise for two 23" mid-1970s CCM frames, a Targa with hi-tensile steel and a Mistral with Reynolds 531 plain gauge. This would be comparable to comparing a Raleigh Record and Super Course. The difference came out to just over 500g or about 1.1 lbs.
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Old 05-06-22, 07:29 AM
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Originally Posted by T-Mar
The difference in frame weight is easy to calculate if we make some assumptions:

1. The gauge used in the top and down tubes are the same as the seat tube.
2. The density of 2030 and 531 is the same.
3. Fork, stay and head tube material is the same.
4. Frame fittings are the same.
5. Geometry is the same.

Assumptions 3,4 and 5 reduces the difference to a comparison of the main tubes. At that point it comes down to an easy calculation of the volumes based on measurements of the frame tubes and applying the steel density.

I did this excercise for two 23" mid-1970s CCM frames, a Targa with hi-tensile steel and a Mistral with Reynolds 531 plain gauge. This would be comparable to comparing a Raleigh Record and Super Course. The difference came out to just over 500g or about 1.1 lbs.
Doesn't your volume-based calculation need to know the wall thicknesses of the tubes?
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Old 05-06-22, 08:07 AM
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Originally Posted by Road Fan
Doesn't your volume-based calculation need to know the wall thicknesses of the tubes?
Yes but that is easily calculated, at least for the seat tube, as we know the seat post diameters, while dimensions for seat post clearance and the outside diameter of the seat tube are standard. Then we have to apply assumption 1 for the top and down tubes..
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Old 05-06-22, 09:44 PM
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Originally Posted by T-Mar
Yes but that is easily calculated, at least for the seat tube, as we know the seat post diameters, while dimensions for seat post clearance and the outside diameter of the seat tube are standard. Then we have to apply assumption 1 for the top and down tubes..
I would worry that errors in the assumptions could cloud the accuracy of this assessment method.
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Old 05-08-22, 08:54 AM
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Originally Posted by Road Fan
I would worry that errors in the assumptions could cloud the accuracy of this assessment method.
Which assumptions are your concern? It's no worse and probaly more accurate than using tubing charts to determine differences in weight.
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Old 05-08-22, 09:13 AM
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Originally Posted by T-Mar
Which assumptions are your concern? It's no worse and probaly more accurate than using tubing charts to determine differences in weight.
If you want highly accurate predictions, I question the need for that goal. For me while low weight feels nice when I lift the bike, it is not significant for my riding. I want to be able to trust that a double-butted frame is actually what it says, but a few once’s of frame is undetectable. I can detect the pedaling response much more than weight.
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