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Old 10-11-11, 07:23 PM
  #62  
LeicaLad 
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Originally Posted by cyqlist View Post
Sorry to belabor the Zeus issue in this thread, but it's been a sore point with me for years. I'm surprised that Sutherlands would get it wrong, but would be more surprised if they made them in both 120 and 119 bcd.

Here is my photographic evidence, taken on a flatbed scanner.




The trig constant to convert distance between adjacent bolts to bcd for a 5 arm crank is 1/sin(36) = 1.7013. Or for a given bcd divide by 1.7013 to get the expected bolt to bolt measurement. Thus:

120mm bcd = 70.53mm bolt to bolt
119mm bcd = 69.95
118mm bcd = 69.36

You can look at the above and see for yourself which it is.


Slightly more on topic, here is my triplized Zeus crank which I drilled for a 58mm bcd granny ring:



I later regretted that I didn't at least attempt to drill and thread the holes blind so they wouldn't show from the outside.

Ooooh! One of the exotic and uber-rare 36t Zeus rings. I've let so many chances pass at buying a nice Zeus crankset, simply because I'd only want one if I could score a 36t ring. Otherwise, why leave a Stronglight 93 behind. As for the drilling, notice that even the Campy factory drilling goes thru the arms. When there's bolt there, it looks okay.

Thanks for the measurements, too. I've long been a fan of Zeus parts, but have yet to own a crankset. (But I have a NOS 50t waiting for the day a 36t ring appears!)


As for costs, et. al. Several of the forums have arranged group buys, etc. etc. I'll not push the subject, and happy to deal thru PMs, too, BUT this ain't commerce and is within forum rules. This is creative research and prototype development. Defensible, FWIW.

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1959 Hilton Wrigley Connoisseur (still my favorite!)
1963 Hetchins Mountain King (the gravel grinder)
1971 Gitane Tour de France (The War Horse)
1971 Gitane Super Corsa (The Garage Queen)
1980 Ritchey Touring (The Grail Bike)
1984 Tom Ritchey Team Competition (NOS show bike)
(replacing the stolen 1981 Tom Ritchey Everest custom)
1985 ALAN Record (Glued & Screwed. A gift.)
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