I didn't follow the "Tell me about Bottom Brackets" thread because I didn't think I knew a lot about them nor had any strong opinions. I rarely seem to have any trouble with any of the BBs I have owned. But in the last couple of weeks I have spent two afternoons playing with bottom brackets and now find I do have some definite opinions. I just now scanned through the 67 posts to that thread and will not be repeating nor challenging any of the opinions expressed there. My observations are entirely about installing and adjusting BBs. First my experience, then my observations.
This odyssey with bottom brackets began when the tandem returned from the powder coating and needed to be rebuilt. I had decided to replace / upgrade the Origen BB with a PW, because I had swapped for one on this list & replaced the bearings (LBS quick & easy). I soon discovered that the shell needed a considerable amount of cleaning so stopped trying to get the PW rings to thread and went to cleaning. Then, just to be on the save side with delicate threads, I installed and reinstalled the Origins till I was comfortable everything was moving smoothly, then installed the PW. Today I began working on the beautiful new Clementine, which I bought for our daughter to help her pull our grandson around town without having to straddle the bar on her almost 20 year old SOMA Dbl. Cross. This project consists of moving parts from her mother's '84 Specialized Sequoia, which hasn't been ridden since Betty Foy moved into the house. Since the Clementine comes with a Tange BB, I began by trying to move the Shimano 600 Crank set. I took off the drive side but then discovered it was no where close to fitting on a 107 BB. I decided to move the BB, a Stronglight of unknown age, but when I tried to remove the left side crank the threads stripped out. After much struggle was able to get the whole assembly out of the frame but then couldn't get the crank arm separated from the BB. After quite a bit of effort I doused it with liquid wrench, set it aside, and began to look for another solution. Since I had an old, nice and unused Specialized crank arm that looked a lot like the 600, all I needed was another BB. It occurred to me that I had often thought that my Trek 620 BB was too long for the Sugino crank, but that it would probably be OK for the Clementine and the supplied Tange could go on the Trek. So I swapped the two BBs, but the 600 still wouldn't fit. The Trek has a rather odd, 110.5 BB, with no name on it. It worked pretty well and I wondered where it came from. Then I got out the Origen from the tandem but quickly realized that it too would be too short. At this point I returned to the 600 & the stuck Stronglight and discovered that my ratchet extender fit into opening on the crank arm and a couple of minutes of hammering on it freed up the BB. So the Stronglight BB went on the Clementine along with a Shimano 600 drive side crank and a Specialized left side. The Trek got put back together with the no name BB & Sugino crank. These BBs involved three completely different assembly techniques and I found that that the way they came together and the quality of the material and threads made a huge difference as I worked with them. Bottom Bracket shells are way more vulnerable to grit, grime and paint residue than any other part of a frame. The fine reverse threads set them up for problems. And, here's the bottom line, the current strategy of installing them with a multi spline tool that has about two mm of depth multiplies the awkwardness. Additionally, the quality of the material on the BB threads varied greatly. The easiest to install are the Phil Wood. The threads on the cup are very good and the PW tool gives good adhesion and a 3/4 wrench makes for easy adjustment. You do have to do the job twice, once to line things up and once to install with locktite, but all in all pretty straightforward. The second easiest to work with was the Stronglight, which turned out to be a huge 124mm. This was definitely old school. It required a large cone wrench, a pin spanner, and a locking wrench. All of which I happened to have because I too am old. But these tools give good points of contact and ergonomics. Both the fixed and adjustable cups have strong threads on them that gave me confidence that they would not be easily damaged. Like the PW, the Stronglight allows for easy adjustment of the load on the bearing, but not the lateral variation that PW offers. Of the three contemporary BBs the No Name and the Origen were clearly better put together than the Tange. The latter had threads on both sides that quickly showed signs of ware after two bouts of installation & removal. I have not worked with either the White or SKF BBs. I know the White uses the same Park BB tool but don't know how much depth of contact they offer. White also requires a lock ring wrench, which allows for adjusting the load. Bottom line, I will avoid Tange BBs in any future purchase. Michael -- You received this message because you are subscribed to the Google Groups "RBW Owners Bunch" group. To unsubscribe from this group and stop receiving emails from it, send an email to rbw-owners-bunch+unsubscr...@googlegroups.com. To post to this group, send email to rbw-owners-bunch@googlegroups.com. Visit this group at https://groups.google.com/group/rbw-owners-bunch. For more options, visit https://groups.google.com/d/optout.
