Bob,
Well, last week I fitted a GB spearpoint stem to a set of the old GB touring bends - the ones with the scalloped ferrule (0r is it fitting a set of GB bars to the stem?).
It's not according to Hoyle, but I used a large flat-blade screwdriver to pry apart the clamp area after removing the bolt. Proceeding fearlessly, possibly because I had at least three other spearpoint stems, I opened the gap to approximately 10-12mm, maybe a tad more. No ping or crack. The bars slipped right through and inserting and tightening the bolt brought everything back to normal.
Perhaps I was lucky, but it occurs to me that those stems are pretty hardy. I've no way of knowing how many times a similar operation had been performed on this stem and repetition would no doubt weaken the stem. But it seems unless one changes bars on a regular basis, the stem ought to survive the relatively few times this operation is necessary.
Same approach has worked on 3T and Cinelli stems.
Bob Hanson wrote:
> Yes Jerry,
>
> I do have a Nitto tool but that is not NEARLY enough spacing range for
> some of my stems. And, they are indeed a 1" clamp area, and going onto
> an alloy bar with the same 1" center and thinner (23.8 mm ?) at the
> brake mount areas in the curves.
>
> I've just always been very concerned with trying to force an alloy stem
> open way too far and having a fracture suddenly appear at a thinner
> portion. I'm talking about already opening the slot from maybe around 3
> mm to beyond 6 mm and this is doing absolutely nothing - except hurting
> my muscles.
> So, how much would be TOO much? Curious how much have you have
> (anyone?) actually spread a stem which was a 34 mm wide cylindrical
> clamp area, one not at all tapered at any point around the clamp area as
> newer ones were to help negotiate through the curves.
> Given enough leverage and I could probably pry the opening a full
> 1/2" - but should I alsoexpect to hear a loud 'ping' at some point when
> the thing finally breaks? Surely there must be a maximum point up to
> which forged dural will be compliant, and then..
>
> Bob Hanson, Albuquerque, New Mexico, USA
>
> _______________________________________________
>
>
--
Phil Sieg
Knoxville, Tennessee
USA