Is this thing beyond engineering limits for diamond framed steel bikes??
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Is this thing beyond engineering limits for diamond framed steel bikes??
It's a giant rider's Raleigh.....
I know that 62+ frames have been built by many companies for a long time, but there must be some kind of negative affect from those extremely long tube legnths between lugs that will make this this so whippy to ride despite the use of straight guage tubing, specially when the rider pulls his stem and seatpost out to maximum legnths like this one that could further worsen the situation.
Didn't see the owner, but he must be as tall as Shaquil O'neal! or he just wants to be seen on the biggest bike he can ride?? This one was parked in front of our office this morning, but I do see these rolling giants very often on the streets.
Should big guys like these have custom frames of a totally different design made for them instead?
......this bike must have of the highest mounted bullhorn bar I have ever seen!
Chombi
#2
Fuji Fan
I'm interested to hear what people say about the frame strength, but that is one heck of a chain.
#3
aka: Mike J.
The fork looks bent, but I'm not going to be the to tell him.
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The real problem here is using 700c wheels on a frame that large, just as it's a problem with frames smaller than 50cm. Certainly, the long spans of the tubing sections will make it very flexible, even with the thickest tubing available. The simple solution would be the use of oversized tubing, but would mean lugless construction. I'm 5'-3" and had to have my frames custom-built until recently with the advent of compact frames.
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Why do so many fixed-gear riders set their seat angle like that?
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Saw this on rivbike.com the other day:
Sizes above 67cm have two top tubes. The second/lower top tube adds strength and rigidity to a super tall frame, by effectively shortening the headtube. This isn't theoretical or innovational; the cheap bikes of China and India have had two top tubes for decades. It's the only way they hold up for decades under the huge loads and rough road they travel.
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The real problem here is using 700c wheels on a frame that large, just as it's a problem with frames smaller than 50cm. Certainly, the long spans of the tubing sections will make it very flexible, even with the thickest tubing available. The simple solution would be the use of oversized tubing, but would mean lugless construction. I'm 5'-3" and had to have my frames custom-built until recently with the advent of compact frames.
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Saw this on rivbike.com the other day:
They do the same thing in Mexico. When I visited the Benotto factory in the early '80s it must have been more than half the bikes they were turning out had double top tubes. I've always wanted one. Makes no sense for me (I ride a 51 or 52) but still cool.
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I'm amazed how somebody hasn't come in yet and said how that's a total lie made up by the Satan (aka Grant Petersen).
They do the same thing in Mexico. When I visited the Benotto factory in the early '80s it must have been more than half the bikes they were turning out had double top tubes. I've always wanted one. Makes no sense for me (I ride a 51 or 52) but still cool.
They do the same thing in Mexico. When I visited the Benotto factory in the early '80s it must have been more than half the bikes they were turning out had double top tubes. I've always wanted one. Makes no sense for me (I ride a 51 or 52) but still cool.
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#17
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1957 Phillips P.10 heavy roadster, the bike the Chinese Flying Pigeon PA-06 and Indian-made Hercules roadsters are based upon.
The double top tube was an option for both the 22" and 24" frame.
Anything above 24" had the double tube, so I'm told.
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#19
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That's nothin, hehe.,,,,BD
I saw this bike in person at the shop he bought it from. The saddle came up to the middl of my chest, and I ride 60-61cm frames
I saw this bike in person at the shop he bought it from. The saddle came up to the middl of my chest, and I ride 60-61cm frames
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So many bikes, so little dime.
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Twin top tubes were copied from early motorcyles. On motorcycles the twin top tubes provided necessary extra strength (and a convenient way to mount the gas tank) but on bicycles they were purely a styling exercise. The extra strength was not required and the extra weight was not as a big a concern as the appearance. Bicycles with twin tubes are generically referred to as Motorbikes, in deference to the original inspiration and the original Schwinn model name. However, I guess they would make practical sense in undeveloped countries where large, heavy loads are still carried on the bicycle.
Most manufacturers offered bicycles in 21", 23" and 25"diamond frames, as this covered the vast majority of the adult population. However, to cover the extremes many manufacturers would also offer their most popular model (usually one up from the bottom of the line) in a very small and very large size. The former was typically a 19" mixte and the latter a 27" (68.5cm) diamond frame. The LBS I worked at didn't even stock them, but every so often we would order one for a customer. I never heard any complaints about the frame characteristics. Nobody ever commented that the frame was whippy, compared to the 23" or 25" they rode when they were a youth. And I never test rode one, because even with the saddle all the way down, I was hyper-extending my legs.
Most manufacturers offered bicycles in 21", 23" and 25"diamond frames, as this covered the vast majority of the adult population. However, to cover the extremes many manufacturers would also offer their most popular model (usually one up from the bottom of the line) in a very small and very large size. The former was typically a 19" mixte and the latter a 27" (68.5cm) diamond frame. The LBS I worked at didn't even stock them, but every so often we would order one for a customer. I never heard any complaints about the frame characteristics. Nobody ever commented that the frame was whippy, compared to the 23" or 25" they rode when they were a youth. And I never test rode one, because even with the saddle all the way down, I was hyper-extending my legs.
#23
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Well, this turned into a neat thread fast. How tall is Yao Ming? 7' 10"? If the other guy wasn't there I'd wonder how they found such small MTB wheels... That Pederson is completely out of here. I wonder if it's comfortable.
My father's Bombadil isn't nearly as stiff as I would have expected, even unloaded. I think it's basically at Atlantis with an extra top tube.
My father's Bombadil isn't nearly as stiff as I would have expected, even unloaded. I think it's basically at Atlantis with an extra top tube.
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