💾 Archived View for zaibatsu.circumlunar.space › ~solderpunk › bikes › franken-peugeot › log › afg_2… captured on 2020-09-24 at 02:12:16.
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September 20th, 2018 -------------------- Due to various instances of travel, sickness and family visiting, I've not put much time into either working on or documenting the Franken-Peugeot project since I last wrote. I removed, cleaned and reinstalled the saddle, after realising in my last post that it was the source of the squeaking which had been troubling me. That noise has not returned, but it didn't take long at all before another horrible noise from the bottom bracket area (or so it once again seemed) started bothering me. After lots of trial and error, I succeeded in localising it. If I pedalled as hard as I could with my left foot, and used the absolute bare minimum amount of force required on the right foot to keep the pedals turning, the noise went away. If I did the opposite, it immediately came back. So the right-hand, i.e. drive-side, part of the bottom bracket seemed to be where the problem layed. Today I rode the bike to the co-op for the first time in quite a while (to my surprise and consternation, the bike was *nearly* silent the whole way, but did get noisier in the expected way toward the end). I wanted to take a look at the inside of the bottom bracket, and check the cup (which was already installed when I got the frame) for obvious problems. I was hoping that something relativley minor, like a good clean and regrease, or a tightening of the cup in the frame, would solve the problem. Because I had such trouble getting the left hand crank to stay securely on the spindle (and it still feels plenty secure, by the way), I was very reluctant to remove it, which you would normally do in order to get access to the bottom bracket. However, I was successfully able to leave it on, using a crank-puller tool to remove only the drive-side crank, and then removing the adjustable BB cup on the non-drive side and removing the left crank and spindle as a single unit. Shining a torch down into the fixed cup confirmed the absolute worst. The race was *badly* pitted, for about 90 degrees worth of rotation. The damage was worse than what I had seen photographs of in articles telling you what to look for, so it seemed very likely that this was the cause of my woes. I'm very unclear of the timeline here. It seems inconceivable to me that the cup could have worn down to this state from being nice and smooth in the short amount of time and few amount of miles I have put on this bike. They're made of hardened steel and are supposed to be very durable. But then, if the cup has been horribly worn the entire time, why did it not start making these horrible sounds until just recently? Did using a rubber mallet to whack the troublesome left crank onto the spindle cause the spindle to ram the balls against the fixed cup, creating damage that wore quickly? My memory of installing the bottom bracket in the very first place is quite hazy. It was one of the first things I did, back when I had no idea what I was doing and had not read 10% of what I now have on bicycle mechanics. I was blindly following the instructions of one of the older guys at the co-op who has moderate but not great English. Did we check the condition of that cup? Or just assume it was okay because it was in the frame? I just don't know. Whatever happened, it was clear the cup had to come out. This can apparently be incredibly difficult, but I managed it with some help by putting the flat edges of the cup into a bench vice and using the entire bike frame as a giant lever. Paying careful attention to the direction in which it unscrewed, and the size of the threading as indicated by the text on the lock ring of the adjustable cup confirmed one of my worst fears about this bike. Old threaded cup and cone bottom brackets like this were mostly one of four different incompatible size/threading standards, from different countries who were major players in the bike industry. There are British, French, Italian and Swiss standards. In the end the British standard won out and because the international standad, and from the 90s onward new bikes never used anything else. This means that today, cups sized to the other standards are speciality items. They're harder to find and more expensive, in proportion to how widely used they were during the hey-day. Peugeot, as you would expect, traditionally used the French system, and switched to British like everybody else during the late 80s, but only after a brief transitional period where they used Swiss bottom brackets for a few years, and my frame is threaded for Swiss cups. Guess which of the old standards was by far the least widely adopted, is very rare now and is today only manufactured by a very small number of very high end brands who charge a fortune, knowing that people with valuable vintage bikes that need them will pay whatever they need to? Yup, Swiss. If I'd needed French or Italian cups, it would have been a setback, but I'd have had options. For a moderate price I could get a nice, modern cartridge BB with sealed bearings that would screw right in. But the Swiss cup thing is like a death sentence for a low-budget Franken project like this. I was prety despondent. I knew I had options, but I would end up spending almost as much as the entire bike had cost me on obscure BB parts. I honestly wondered about hunting for a new frame to transfer everything else to. The co-op had a small bin of loose cup and cone BB parts, totally unabelled and unsorted of course. I started sorting through them glumly, squinting at the threads to see if they were left or right handed. I started making a pile of candidates. Without a proper tool to measure thread size, you have to be careful here. The British and Swiss systems are only *slightly* different. If you use enough force, apparently you can usually jam a British cup into a Swiss frame. It will screw up the threads and you may never get it out again, but some desperate folk have resorted to it. I did *not* want to do this by accident, so I tried very gingerly screwing in possible cups with just my fingers, stopping at any resistance I couldn't get past with just a little bit of effort. I honestly didn't expect anything to fit, and the cup after cup either got stuck early on and was rejected, or went in no problem but was just a litle too lose and never quite stopped wobbling. And then, one fit just right. I was flabbergasted and elated. The internet had prepared me for this part to be unobtainium. Just finding one that day floored me. In retrospect, maybe this shouldn't be such a shock. All it would take is for one other mid-80s Peugeot to have been scrapped at this place in the last 30 years and a Swiss cup would have made it's way into to the bin. The chosen cup was not *perfect*, but it was in very good condition, and indisputably much, much, much better than the one it was going to replace. I could not reasonably have hoped for more. At this point I didn't feel I had time to do a non-rushed job of reinstalling everything, so I walked the bike home, with the bottom of the frame totally open and the drivetrain parts in my hands. During the comic week I will get everything as clean as I possibly can. Next Thursday I will reinstall everything, with as much grease packed in as I can, and carefully adjust the bearings to be as good as I can get them. Hopefully this will result in a nice quiet drivetrain and I will finally have some confidence that this thing is ready for use. As a nice bonus, since I have to reinstall the right crank, now I can do it properly, the way I did the left crank a while back. While I'm happy that the project is still on track and something resembling an end (to major work, at least) is in sight, this epsiode really made me aware that this bike is heavily dependent on some pretty obscure vintage parts which are only going to get harder to find. It's not likely I'll be able to keep this bike alive for years and years to come without spending more money than would make sense. In some ways, this is good to know. The real value of this bike has been what I've learned in the process of building it, good knowledge and experience I can put toward other projects in the future. Knowing that I'm not likely to be riding this thing 10 years from now means I don't have to worry about treating it with kid gloves. Of course I'm not going to deliberately abuse it, but my mindset is going to be "ride the heck out of this thing for as long as you can and cherish every moment of it".