Subject: Re: Spoked Posted by: Pete on December 16, 2002 at 04:34:14: In Reply to: Spoked posted by Dan on December 15, 2002 at 23:21:04:

Message: >I am considering using Sapim spokes on the wheels I will be building w/(Mavic Open Pro). Front Sapim 14/17 "Lasers" and the Rear 14/15 "Race". Sapim manufactures nipples for their spokes that are brass called "Sapim Polyax" 12mm and alloys that are 14mm. These are suppose to aid with spoke alignment in the way they sit in the spoke socket. >From the picture on their website the Polyax nipples look like the underside of the head is hemispherical rather than conical like some nipples. That allows them to pivot and turn without bending the end of the spoke on a ferruled rim, like the Open Pros. A non-ferruled rim is limited by the depth and diameter of the drillings. The problem becomes greater with more crosses in the lacing pattern. >My questions are >1. If I use alloy that are 14mm do I need to deduct from the spoke calculated length? It seems that the online spoke calculators base the ERD on 12mm standard nipples. >I think they're actually adjusting the length based on a typical nipple head height of 3mm. The heads are the same on most longer nipples - it's the barrel and flat section that's longer. A random 12 mm nipple I just measured from my used stash has 9 mm long threads and a 16 has 11 mm of threads, so you might or might not need to adjust the length so you don't run out of threads. You'll have to find a friendly dealer to measure them. The 14/17 spokes will stretch more under initial preload (2 mm?) than the 14/15's, too. >2. Sapim sells 12mm brass nickel plated nipples. Is the small amount of extra weight effect rotational weight? >Your tire, rim, rim strip and tube probably total 700 grams. Think you'll notice an extra 1 or 2 %? >3. Do brass nipples build a better and stronger wheel. Can you reach higher tension (with in safe range) easier with brass than alloy? >It's easier for klutzes to strip the threads and round the flats on alloy nipples. I've never had that problem even with the 40% greater tension required by Ti spokes. Brass nipples won't gall when used on unferruled rims. Colored alloy nipples are flashier. Alternating red, silver, blue and silver could show you are a proud American (or French, Czech, Russian, etc.) Replace the blue with green on your Colnago or Masi. When people ask about it you can casually mention you built them yourself (unless they're out of true - then blame me or anybody else who answers your e-mail) >4. Suggestions and comments about the use of Sapim spokes in general. >Hard to find in Northern California. Anybody know where I can get them? ThorUSA is the distributor. Many pro teams use them. I wish I could, too.