Saturday, September 25, 2010

Bob Jackson tandem

Completed, if not finished, this morning.

I have had the frame for about 20 years, but have not ridden it since the mid '90s.
Earlier this year I had some good rides with Gayle on Worrall's tandem, so I decided to build this one up with modern components so that we can shift gears while climbing or sprinting out of the saddle

Fortunately, when I was younger and stupider I had respaced the dropouts back so that a modern rear wheel would fit.
The drivetrain is a Campagnolo/Shimano/SRAM hybrid, with Campagnolo Chorus 10 speed Ergopower and rear derailler and a Shimano Ultregra hub with SRAM PG970 12-26 cassette.
A J-Tek Shiftmate corrects the cable pull of the 10 speed Campag shifter for the 9 speed cassette.
Cranks are Suntour Superbe Pro, rethreaded by Bruno at Cycle Express, on Campagnolo Veloce 111mm bottom brackets.

Chainrings are 52/38, which should give us a low enough bottom gear, but might leave us a bit short at the top end.

Because of the curved seattube, the front derailler needs to be positioned a couple of centimeters further back, hopefully easy to achieve by making an aluminium packer to go between the mounting bracket and the derailler.

The brakes are self-energising cantilevers. Front is Scott SE, rear is Suntour XC Pro.

All the Bob Jackson tandem photos

Friday, September 17, 2010

Scraping the bottom of the barrell?

This week I broke one of my rules of being on holiday, and visited a couple of local bikeshops on my own time.

On Tuesday I went to Cycle Express to collect some Suntour Superbe Pro cranks that Bruno had rethreaded for use on my tandem.

Twice, I found myself at T.White's Bikes.
Saturday evening for the excellent CGG Jenna Makgill fundraiser, which left me financially poorer but hopefully rich in kharma; then again yesterday to get a set of single chainwheel attachment bolts for the aforementioned tandem.

This is not a normal situation for me- having assembled my last four vintage bikes almost entirely from parts that I had on hand, I don't expect a project to grind to a halt for want of a packet of bolts.
Perhaps this means that I am finally scraping the bottom of my barrell?

I doubt it.
Despite using some of the pile of parts into bicycles, and some recent success selling surplus frames on Trademe, my shed looks no less cluttered.

Friday, September 10, 2010

Something to do in the weekend

It would be bad manners to miss out on this opportunity to support the fabulously amazonian Jenna Makgill

Monday, September 06, 2010

Mine at last!

This morning I won the ebay auction for this lugless Tom Ritchey road frame.
I have been looking for one since about 2003 but this is the first one I have found in my size.
According to the vendor, it dates to the late 70s. With fully lugless, fillet brazed construction and a sloping fork crown it bears a strong resemblance to the lugless Ritchey frame from the Palo Alto Bicycles catalog.

Now that I have won the auction, I can start accumulating parts.
My plan is to use a set of original Suntour Cyclone deraillers that CTB gave me, with early Suntour Superbe cranks, brakes, shiftlevers and hubs.
The rear dropout spacing is 125mm, so a 7 speed drivetrain should be possible.
I have a dilemna regarding bars stem & seatpost, whether to go for period correct parts; or to use my 1990s Nitto-made Ritchey WCS stem possibly with a Nitto S83 seatpost.