Time to put the group together!
Last time I installed piston rings it took me a couple of hours and there were chopsticks, screwdrivers and swearing involved. With that experience in mind I came up with this little device to take the hassle out of the task. The thin lip at the bottom that fits over the outer diameter of the group is very fragile and will eventually have to be replaced with some metal but now I can put on a set of seals with my bare hands in 30 seconds!
Now it is really time to put the group together.
Having spending hours faffing around with threaded rods and myriad nuts and washers the last few times around, this time I decided use the milling machine vise to compress the spring.
Spring compressed and pin in place.
First completed assembly from new parts!
Everything works as it should, but I don't have any more pictures, for reasons that will become clear below.
Compressing the spring with the milling vise worked but it was only marginally faster than the threaded rod method and, more importantly, it means that all work has to be done with the assembly in the vise. Furthermore, the pin had to be driven into place with no support behind the cam - a very, very bad idea as I found out when I broke the fork while I was disassembling it.
So what did we learn? One, that it isn't a good idea to do anything on Fridays at 5. Two, don't use the milling vise to compress the spring. Three, that the 8mm off-the-shelf knurled pin that I found just doesn't cut it. First, I could only find 8x30 and the missing 2mm that aren't holding the spring makes me nervous and second, the extra millimeter in diameter makes the difference between the pin clearing the top of the bearing plate posts or not - making installation harder. This is a pain as the 7x32 pin that Brugnetti used is emphatically non-standard. They had some factory make 10,000 of them and forgot about the problem - which I guess is what I will do too :).
Last time I installed piston rings it took me a couple of hours and there were chopsticks, screwdrivers and swearing involved. With that experience in mind I came up with this little device to take the hassle out of the task. The thin lip at the bottom that fits over the outer diameter of the group is very fragile and will eventually have to be replaced with some metal but now I can put on a set of seals with my bare hands in 30 seconds!
Now it is really time to put the group together.
Having spending hours faffing around with threaded rods and myriad nuts and washers the last few times around, this time I decided use the milling machine vise to compress the spring.
Spring compressed and pin in place.
First completed assembly from new parts!
Everything works as it should, but I don't have any more pictures, for reasons that will become clear below.
Compressing the spring with the milling vise worked but it was only marginally faster than the threaded rod method and, more importantly, it means that all work has to be done with the assembly in the vise. Furthermore, the pin had to be driven into place with no support behind the cam - a very, very bad idea as I found out when I broke the fork while I was disassembling it.
So what did we learn? One, that it isn't a good idea to do anything on Fridays at 5. Two, don't use the milling vise to compress the spring. Three, that the 8mm off-the-shelf knurled pin that I found just doesn't cut it. First, I could only find 8x30 and the missing 2mm that aren't holding the spring makes me nervous and second, the extra millimeter in diameter makes the difference between the pin clearing the top of the bearing plate posts or not - making installation harder. This is a pain as the 7x32 pin that Brugnetti used is emphatically non-standard. They had some factory make 10,000 of them and forgot about the problem - which I guess is what I will do too :).
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