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flag fishizzle
Posted: Nov 2, 2007 at 17:03 Quote
enjoy
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1574339

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1574374

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1574376
flag potvinwannab
Posted: Nov 2, 2007 at 17:07 Quote
ah dude ive always wanted to make a bike with no welds...unfortunately i am poor and have no experience in metal and am 14 years old at the moment. That is sick, if only they could forge an entire hollow aluminum frame. Is it a production frame?
flag
Posted: Nov 2, 2007 at 17:07 Quote
that looks sweet
flag gabodude
Posted: Nov 2, 2007 at 17:14 Quote
I've barely been welding bikes for a year and they're already looking for a way to put me out of a job!

Nice work though.
flag fishizzle
Posted: Nov 2, 2007 at 17:35 Quote
yeah thats a production frame, the rear swingarm is hollow but the rest of the frame is an I beam construction. £2000
flag balog
Posted: Nov 2, 2007 at 17:41 Quote
Are these frames actually forjed?
I found the factory´s website but there is no information there...

anyone?!?!
flag fishizzle
Posted: Nov 2, 2007 at 18:36 Quote
no they are not forged they are cast in the same way aerospace components are with sand moulds.
flag pbuser16709
Posted: Nov 2, 2007 at 20:37 Quote
Interesting!

I'm concerned about torsional stiffness, though, because I-beams aren't the best in torsion.
flag fishizzle
Posted: Nov 4, 2007 at 14:55 Quote
surely they are as good as tubes? apparently this frame is really stiff because of its I beam and raceface use an I beam for their cranks.
flag cruelty-and-the-beast
Posted: Nov 4, 2007 at 15:01 Quote
gabodude wrote:
I've barely been welding bikes for a year and they're already looking for a way to put me out of a job!

Nice work though.


That sucks, im trying to get into bike welding,
flag pbuser16709
Posted: Nov 4, 2007 at 15:20 Quote
fishizzle wrote:
surely they are as good as tubes? apparently this frame is really stiff because of its I beam and raceface use an I beam for their cranks.

Hollow forgings are better for cranks - and hollow forgings are essentially tubes. Welded tubular cranks may even be better. Of course, you have to factor in a LOT of things beyond just the construction technique, but when it comes to twisting loads, tubes are superior.

I-beams are the best structures for loading in a single plane. That bike should be really strong near the head-tube, if the design and construction are good, but I'm still concerned about torsional stiffness.
flag nick65
Posted: Nov 4, 2007 at 15:26 Quote
WOW thats all i can say is wow how much u think a machine like that would be
flag fishizzle
Posted: Nov 4, 2007 at 15:31 Quote
well the frame is £2000 and the full build i would estimate is well over £4000 so thats something like $8000
flag fishizzle
Posted: Nov 4, 2007 at 15:37 Quote
r-m-r wrote:
fishizzle wrote:
surely they are as good as tubes? apparently this frame is really stiff because of its I beam and raceface use an I beam for their cranks.

Hollow forgings are better for cranks - and hollow forgings are essentially tubes. Welded tubular cranks may even be better. Of course, you have to factor in a LOT of things beyond just the construction technique, but when it comes to twisting loads, tubes are superior.

I-beams are the best structures for loading in a single plane. That bike should be really strong near the head-tube, if the design and construction are good, but I'm still concerned about torsional stiffness.

oh fair point, but how much of a torsional load is a bike encountering? and surely this frames torsional stiffness/ and yield point in areas like the headtube is alot better without welds?
flag pbuser16709
Posted: Nov 4, 2007 at 15:57 Quote
fishizzle wrote:
oh fair point, but how much of a torsional load is a bike encountering? and surely this frames torsional stiffness/ and yield point in areas like the headtube is alot better without welds?

Torsional stiffness is very important to how solid a bike feels. The loading is a lot less than the in-plane loading, but it's still a real concern.

It's true that eliminating welds is a good thing, but drawn and cold-worked tubes are a lot better than cast metal. I'm not sure how those two factors offset one another.
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