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View Full Version : The different ways of producing 3/2.5 Ti bikes


Kontact
02-20-2012, 01:02 PM
I was reading the Pricing thread and it sounded like it really isn't very clear how different makers do things. Here's what I know on the subject:

Your basic Ti road bike starts with (usually) .89mm wall thickness 3/2.5 aviation hydraulic tubing and some custom turned/machined parts for headtube, dropouts, brake bridge, seat cluster etc. Paragon machine supplies most of those bits to the smaller guys.

Butted tubing is either lathe sanded down from the outside (Merlin, Seven, Spectrum, Feather, old Litespeed) or swaged (Serotta, Reynolds).

The tubes can also be shaped by swaging, twisting or compression. While they do this on stays, Merlin/Spectrum/Seven avoid cold working the tubes as much as possible, believing that cold working changes the ride character of ti tubes to their detriment. Some people say they're just being cheap, but Spectrum had 10 years of ABG production to take advantage of their swaging and compression dies and didn't use them.

Litespeed/Lynskey/Serotta are big on cold working manipulation, and have produced the most novel tube shapes. I have an old Litespeed with tapered tubes that are almost identical in profile to Legend/Colorado tubing. Reynolds also supplies internally butted tubes to anyone who wants to pay for them, but they come round.

Welding passes are also a potential labor cost. Lynskey does a single pass, others do a fusion then fill, or fill then smoothing.

Finally, there's bits and details. Is the seat binder welded or a collar? How complicated are the dropouts to machine and weld? Serotta has the most complicated dropouts and is the only company I've seen that lightens the BB shell by milling. (For the record, I think that welded bottle bosses are not always an upgrade. If the tubes are butted, that's putting a HAZ right in the middle of a really thin bit of Ti).


So, price aside, I do think that an all Ti Legend is the most labor intensive Ti bike available. Really complex machining on the dropouts and BB, very manipulated tubes in both shape and butting. Whether that is worth the extra thousands ($1000 more than a Helix, $1500 more than Seven Axiom SL, $2200 more than a Kish butted Ti) is up to the consumer, but I think the case can be made that there is more going on with the Legend.