Thursday, February 18, 2010

Coupled

I got the RB-T back from Glen. He put S&S couplers on it. And hooked me up with a fancy Campy seatpost and a nice old Dura Ace headset.

I rode it today for the first time. It's the same old great bike, but now it travels better. Yay.

I'll get a soft case for it. I plan on practicing the tear-down and build-up so I can do it blindfolded in under 2 minutes.

The tube around the coupler keeps out the gunk. I'll get a smaller one for the top coupler.

Glen found the same crack forming in this bottom bracket that he fixed on the RB-1. Looking into the bottom bracket, it's obvious there was not any brass coming out of a couple of the brazes.


In addition, the seatstay was showing signs of separating at the seat collar. Just like the RB-1. Hmm. I'd say that's a trend. Glen did the same fix and brazed on a canti cable guide/hanger to stiffen up that joint.


If you're a comment reader then you may have noticed my comments earlier about the tubing on this bike. Cutting the tubing provides a non-ambiguous measurement of the wall thickness. The 91 RB-T appears to use 8-5-8 tubing. Who knew? That explains it's noodley wonderfulness.

All in all, it's a fine bike and I love it more than ever. I took the trails home tonight and it's the same righteous bike. With the 35mm Pasalas, this bike is about the perfect all-rounder for me.

6 comments:

FBC Spokane said...

Under two minutes? Are they chasing you out of the airport?

Unknown said...

what dimensions of the tube do 8-5-8 actually measure?

John Speare said...

Andrew: 8-5-8 refers to the butting profile of the tube. That's the width of the steel tube thickness (.8mm - .5mm -.8mm). My assumption, based on later B'stones that used 022 or 019 (model names) of Ishiwata tubing was that this was 9-6-9. The difference in width is minor, but in standard diameter (smaller) tubing, it makes a big difference -- as the stiffness of tubes increases exponentially with the thickness of the tubing walls. This bike would be considered very noodley by people that ride contemporary bikes. But i like the ride -- it doesn't feel noodley to me, it feels springy -- it gives something back.

Tarik Saleh said...

Good luck with this one. I am loathe to put any money into standard diameter frames that are poorly brazed. Once the start breaking they keep on breaking. All that flex plus shitty production braze means crack city. Again, production bridgestones = not worth it especially now, 20 years out. Better to start from scratch, but since you are already there, have fun! Looks good otherwise/

John Speare said...

Tarik: that's what Glen said!

glen c. said...

Tarik, clearly you do not know John that well yet. I expect to be gainfully employed by his fanciful notions for years to come. Huzzah, Bridgestone!Keep 'em coming!