I think Alpha's must be making them too tight to start with ?. Cheers Bill.
E: Engine Big End Replacement
- Thread starter Cyborg
- Start date
I recently learned what they are meant for, ( I found a smaller version in some stuff I acquired) but they basically operate on the same principal as the one shown in tuning for speed. I "assumed" rather than spend half of my remaining time on earth making a copy of what is in tuning for speed, I could make threaded adjusters for an expanding mandrel. The adjusters would secure the outer portion of the mandrel in place, or I could even hold it in place with the appropriate Loctite Y/N? An application of the correct grinding paste and slide the rod back and forth with the mandrel turning in the lathe. It would be a light load. I would think that it would be fairly accurate. Why would it not work? I don't want to bodge anything. Before I do that, I'll swallow my pride and send it out.
If you are good with a lathe, Why not turn up a long bit of steel, About 1. 7/8", And make it alter by a thou, Then 2 thou etc. Cheers Bill.
Bill I would say they make them all like that now because they know that nearly all "Used rods" will be out of round. Once the eye is honed out true again, then the new liner would be oversize on its OD. Cheers............Greg.
Given the importance of the big end rollers having full contact area if the big-end bearing has any chance of a full and happy life I would have thought using a Delapena or Sunnen hone was a given to produce both a round and straight bore. Stone grade is very important to get the correct surface finish and stones wear during use so you constantly need to use a truing sleeve. Proper hones also have a guide so that you hone the big-end bore parallel to the little-end bush.
I suppose I'm saying it would be better to get this job done properly so that you can enjoy the bike rather than having to prematurely split the engine to repeat all your hard work.
I suppose I'm saying it would be better to get this job done properly so that you can enjoy the bike rather than having to prematurely split the engine to repeat all your hard work.
I agree 100% .......... One thing I do not like is having to pull something apart because I got it wrong the first time, and the bottom end of these engines is more particular than most might think, with side by side rods and four main bearings ........It pays to get it right.
Thought about that. I don't know if I would consider my self good. Got a ways to go yet, but I did manage to turn out a few Norton OHC cam tunnels that I'm happy with.
I can't really argue with that and ultimately there is a good possibility that is the direction I will go.... However, I have a couple of extra rods with outer races still installed to practice on. That picture of John Mcdougall shows him using one of those lapping tools and he built some very high mile engines. I don't think for a minute that my skills will ever be as good as his and there are others around here that make me feel humble when I walk into their shops, but they all had to start somewhere. At this point I don't see why I couldn't do something reasonably well if I take my time and proceed cautiously. I may ultimately get handed my ass but it wouldn't be the first time. Anyway... getting ahead of myself. I need to go pick up my new bore gauges and determine if the whole thing is a go or it's all going in the bin.
I got thrown out of school a few time for that... It started with "I can't really argue with that but....."
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I give you a 100 marks for trying.........No one can knock someone for trying, or else none of us would have gotten anywhere with anything...........