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Discussion Starter #1 (Edited)
For those of you looking for something much better than the rubber NOS rollers, I have CNC machined versions out of chromolly steel of both the upper and lower rollers.

They will fit CB/CL/SL motorcycles. Upper roller is a sprocket, lower is a smooth roller. Each have high quality needle roller bearings pressed into them. Upper roller comes with a deformable rivet. Material is chromolly steel. See the following links for purchase.

Both Upper and Lower:
http://www.ebay.com/itm/231576401099

Upper:
http://www.ebay.com/itm/231560299062

Lower:
http://www.ebay.com/itm/231560304770

Link to Instructions:
https://drive.google.com/file/d/0B31LrzzamA7UdER1dnFIX244ZzA/view?usp=sharing


Thanks
 

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Discussion Starter #3
I have both cam chain rollers in the engine of my '73 CB350G that is a street machine. I did not like the idea of running NOS rubber components in my freshly built bike. My background is in mechanical engineering and machining. Designing and producing these parts made sense to me, and now provides a solution to other people like me looking for quality alternatives.
 

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They seem reasonably priced, and obviously look like they will last a lifetime. Another question though, why not just pop for the KA slipper? Honestly not trying to argue, just curious, and before too long I will be in the market for either option. Being able to use stock roller assembly vs. taking material from the head to fit the slipper?
 

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Discussion Starter #5
I personally just liked the idea of being able to use the factory tensioner system, and not having to permanently modify the head. The weak point in the factory tensioner is the rubber rollers that just do not like running marathons in their old age. I figured if i can just improve upon the rubber roller issue, I'll have a very solid and reliable system. I understand the advantages of the slipper, and it definitely has its place. The advantage of using the rollers is if you're on a budget, which a lot of garage builders are, you have the ability to only purchase one roller if that is all you need. The rubber upper roller tends to get trashed quicker than the lower. It is definitely advantageous to replace both rollers while you're in there, but If you're in a pinch and can only financially justify replacing whichever one is chewed up, you now have that option instead of replacing the entire system. I'm also just a fan of working with what you've got. If you've got a roller tensioner assembly, you can just upgrade the rollers and not have to deal with grinding away the cam chain passage to fit the slipper if you do not want to go that route.
 

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I don't have a CB350, but on my old CB77 race bike I had a couple of rubber rollers break up and both times valves were bent, rockers broke and so was I.....

There have been a few steel rollers made over the years by racers. Mechanical noise isn't an issue for racers but chain life is. What is your expectation for durability on the large roller or its impact on chain life? Is it better to run flat side chains rather than stock peanut chains on those wheels?
 

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Discussion Starter #7
The material hardness of the larger roller was specifically selected to be lower than a typical chain link steel hardness. This will drive any wear onto the roller, and not damage the chain. Flat side vs peanut, I would say to stick with peanut because it contours a circle better.
 

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Not trying to put this down at all but is the inner race in the e-bay listing not finished? You can see machining lines needle bearings like hardened and ground surfaces to have life
 

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Discussion Starter #9
Yes you are correct that needle bearings need a smooth and also hard surface to ride on to act as an "inner race" like that of a standard ball type bearing. If you get a little more familiar with how the tensioners on these engines are put together you'll see that the upper roller sprocket does not use the rivet as the actual bearing surface. There is a hardened sleeve that goes inside of the needle bearing that the rivet goes through. If you open the installation instruction link in the first post it will be more clear.
 
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