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Old 11-27-23, 07:47 PM
  #32  
Portlandjim
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Join Date: May 2023
Location: Big Sur California
Posts: 217

Bikes: 1946 Holdsworth Cyclone, 1969 Cinelli SC, 1972 Raleigh Pro, 1973 Merz road bike, 1974 Alex Singer Sportif, 1974 Merz track bike, 1975 Teledyne Titan, 1976 Ritchey road bike, 1977 DiNucci built Merz track bike, 1977 (?) Exxon Graftek, many more!

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Originally Posted by merziac
It would also be notable to understand the reasoning for doing it this way despite the challenge, maybe @Portlandjim will expound on it for us.

Its been interesting to see other builders have an epiphany while looking at mine and we're talking serious, long respected ones.
Originally Posted by bulgie
Well, whether it's really an option depends on your luck finding someone willing to make it. I doubt Jim is offering to sell these (Jim,please correct me if that's wrong).

Most other builders will be put off by the challenge of making those clamps, which are clamping to the blade where it's still oval and tapering. I expect that is very finicky work, unless Jim has some shortcut. It definitely can't be done without the builder having your fork in his hands, because every fork will be slightly different at that point.

I would caution any wannabee rack builders to go a more standard way for your first few racks, don't try Jim's way until you have achieved mastery!
I am not going to make any Merz racks for sale these days! When I designed the Specialized Expedition bike, 1983 or so, I really wanted to offer this bike with serious touring racks. As Mark mentioned above, bicycle frames are not the same even within the same batch of frame/forks with the same size. There is no way to do this in a production setting for a price that any customers would accept. My racks with these clamps are equal in strength and stiffness to brazing the racks onto the frame and fork. Plus, this method allows the option of easily removing the racks for transport on an airplane or just riding the bike without racks. The other problem with trying to sell them on a production bike​, even with an inferior mounting method​, they still cost ​t​oo much, both for materials and labor. In the end I gave up, Blackburn racks were so cheap and worked OK for most riders. My racks will hold up if you want to ride around the world, and are night and day better than Blackburn racks (or any racks!)

. Check out this story from Bicycle World, it mentions my racks.

Mark is correct in his comments about the clamps. I figured out the taper of the fork tubing, this is tricky as the tube is also flattened. Then I made the tube that goes around the fork tube out of thick tubing, the inner and outer are taped using my CNC lathe. This tube is ovalized to match the fork at the mounting location. The threaded barrels are brazed on to this tube using a fixture to ensure that they are postioned correctly, then each clamp is slit using a saw in my milling machine. Getting these clamps onto the rack struts in the correct position is done off the fork in this case, the fork was painted which meant on brazing with the clamps in position is out. All this work has to be done as a one off, it's very time consuming.

Last edited by Portlandjim; 11-27-23 at 08:15 PM.
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