I know, and I couldn't see any stickers in the pictures either. They do look very "low-profile"-- a similar sort of depth to MA-2s rather than the deeper U-shape of an Open Pro.
Quoted message said:
O'Grady was riding Ambrosio rims during the race, probably their "Nemesis" model. You can see the telltale gold-coloured balance weights in this picture:
I thought that a tire valve is even heavier than the rim's pin that holds it together (and, these are retro pinned tubular rims ??) Is the pin THAT HEAVY inside of a 420 gram tubular rim that it needs extra weight ??
I know, and I couldn't see any stickers in the pictures either. They do look very "low-profile"-- a similar sort of depth to MA-2s rather than the deeper U-shape of an Open Pro.
Quoted message said:
O'Grady was riding Ambrosio rims during the race, probably their "Nemesis" model. You can see the telltale gold-coloured balance weights in this picture:
I thought that a tire valve is even heavier than the rim's pin that holds it together (and, these are retro pinned tubular rims ??) Is the pin THAT HEAVY inside of a 420 gram tubular rim that it needs extra weight ??
I thought that a tire valve is even heavier than the rim's pin that holds it together
It may well be. I didn't say the idea had merit.
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(and, these are retro pinned tubular rims ??)
I don't know, but I do know that some modern welded and machined rims still use an internal pin to hold the joint in alignment.
James Thomson
it's not to hold the joint as such, it's to keep the internal welding flash in place and to give the electrode pinch contacts somewhere to bite as they contact-weld the rim ends.
That's quite unlike the solid 1-piece pin I recently pulled out of a dead X517.
James Thomson
how can that be? that's a welded rim. if the two ends are electrically flash welded, and they are, how can you possibly have a single piece since the plug would interfere with the weld process?
That's quite unlike the solid 1-piece pin I recently pulled out of a dead X517.
"jim beam" <[email hidden]> a écrit:
Quoted message said:
how can that be? that's a welded rim. if the two ends are electrically flash welded, and they are, how can you possibly have a single piece since the plug would interfere with the weld process?
I don't know - I don't know much about welding: I'm just reporting what I saw. I still have the pin, but I won't be able to lay hands on it before the weekend, and I don't have a digital camera, but I should be able to post a better description of it.
[the pin is] not to hold the joint as such, it's to keep the internal welding flash in place and to give the electrode pinch contacts somewhere to bite as they contact-weld the rim ends.
I liked the old pinned rims, they had pins kinda like the red plastic strips the held my hot-wheel cars together. The pins would be showing until you tightened up the spokes enough to cause the ends of the rim to collapse inwards and hide the flat pins.
I still have the pin, but I won't be able to lay hands on it before the weekend, and I don't have a digital camera, but I should be able to post a better description of it.
Well, my memory was playing tricks.
There are indeed two heavy little plug pieces, one either side of the joint, each shaped to fit the box cavity of the rim, with a T-shaped channel running through the extrusion. Welding flash fills the gap between the two.