Superblend main bearings for Atlas, G/N15 and P11

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Are there any reasons why the modern Superblend bearings shouldn't or can't be used on drive and timing side for these engines?

Thanks,
Ed
 
Dang! I hope not!! Also, what do you mean by "modern"? I have old Superblends in my P11, (unsure how old, 40-50 years old? but in good condition) Are there more modern ones than those?
 
I'm using Superblend mains in the P11. I replaced and older set of Superblends with a new set of Superblends I got from AN when I swapped the stock crank for a Molnar crank. Same same regardless. I did not have to shim them for end float. There were no shims on the stock crank either.
 
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I'm using Superblend mains in the P11. I replaced and older set of Superblends with a new set of Superblends I got from AN when I swapped the stock crank for a Molnar crank. Same same regardless. I did not have to shim them for end float.
I had to shim mine. All the shimming for end float has been probably the biggest thing to get used to coming from Japanese stuff.
 
Thank you both for responding. I am building a G15 lower end and wanted to be sure that superblends are suitable for both sides.
 
Not to throw a wrench in your plans but some people, as do I, still like a ball bearing on the timing side. But either will work.
 
Not to throw a wrench in your plans but some people, as do I, still like a ball bearing on the timing side. But either will work.
Hello 'rider,
Why your preference for ball bearing on timing side?

Thanks,
Ed
 
Less friction. I have opened engines with 15K and 25K miles still on their original timing side ball bearing, still serviceable. Unless you are building a monster, two rollers are not needed, IMO. All my engines are 650 and 750, FWIW.
 
If you might be interested, go to the N.O.C. website. Look under the technical tab and click commando then bearings. Goes well with a cup of coffee. Mark
 
If you might be interested, go to the N.O.C. website. Look under the technical tab and click commando then bearings. Goes well with a cup of coffee. Mark
I see that RGM supplies RHP timing side ball bearings. But I've heard about sub-standard RHP gearbox bearings in another post. Does anyone know whether the RHP main bearings suffer any problems?

Ed
 
The timing side bearing has less work to do compared to the driveside so can get away with a ball bearing with the added benefit of the end float being controlled by the ball bearing when the timing side crank nut is fully tightened.
 
If you might be interested, go to the N.O.C. website. Look under the technical tab and click commando then bearings. Goes well with a cup of coffee. Mark
I read that before doing my N15 and then, being well-informed, probably did the wrong thing (mix of two types)! :D
 
I rebuilt an Atlas engine with Superblends long enough ago that I don't remember if I shimmed them or not. Anyhow the engine has flat-top pistons and a Commando head and has endured a good bit of thrashing on B.C. and WA cascade mountain roads with nary a whimper.

I did have a footpeg ground and shot my foot off the peg so I raised them subsequently. Now in my dotage they are back down and no more flat bars. I did save the peg rubber which had the bulge at the end ever so neatly ground off. That event says a lot about both the engine and the chassis of an Atlas.

If I finish the kitchen remodel before the snow flies, I'll go ride it some more.
 
Comic relief: I put some sweet billet Magura clip-ons on the P11 when I was in my 40's, but I left the foot pegs in the stock position. It was hard to ride all day with my knees pressed up against my chest. lol Needless to say I did not leave the clip-ons long. Still have those clip-ons.

Superblend main bearings for Atlas, G/N15 and P11
 
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I wouldn't worry about the mix. Honda and KTM have done it that way , quite often in fact.
My big GS1100E Mr. Turbo had crankshaft ball bearings in it. It runs a low pressure oil pump and they are dead reliable bottom ends.
 
I read that before doing my N15 and then, being well-informed, probably did the wrong thing (mix of two types)! :D
Pretty sure a lot of Brit twins came from the factory with a roller on the drive side (to handle the heavier load) and a ball bearing on the timing side (to help control side-to-side movement of the crankshaft).
 
Pretty sure a lot of Brit twins came from the factory with a roller on the drive side (to handle the heavier load) and a ball bearing on the timing side (to help control side-to-side movement of the crankshaft).
Mine spins freely and I couldn't discern any crankshaft end float. We'll see. It's got .040 over NOS/OEM pistons and taller gearing. I won't be flogging it. Much. I took great care putting it together with lots of help from the experts here, but it's my first Norton rebuild so fingers are crossed. I have been moving and changing jobs but all will settled for the fall. I hope to be riding it soon.
 
This seems to be a good Thread in which to try again to correct a common and long held belief about the bearings used to fix the problem of Commando main bearings failing prematurely, particularly after the Combat motor introduction.

While developing the rotary engine for light aircraft use, we had a main bearing failure occur near the end of endurance testing. Although we were able to attribute it to contamination in the oil supply, we decided to call in a project engineer from the bearing company to discuss alternative bearings.
During the meeting between our senior designer, myself and the bearing project engineer, the designer happened to mention Superblend bearings. The project engineer had a good chuckle and informed us that he, personally, had been involved with that particular problem and the "superblend" bearings were just ordinary Extra Capacity Bearings (the "E" in the bearing number standing for "extra"), not "barrel" rollers.

I and a few others have mentioned previously that "superblend" bearings were not a real thing, but nobody seems to notice. I don't expect this post to change that but I have to try.
 
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