one peice rear axle.
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This does not directly answer your question but . . .
I'm assuming that you have a drum brake Commando rear wheel and you want to keep it simple. Get an Atlas rear wheel; it's much stronger because there are three cone shaped lug nuts that center and tie the break drum to the wheel; you have to change the offset slightly, not the same on an Atlas as on a Commando.
I'm assuming that you have a drum brake Commando rear wheel and you want to keep it simple. Get an Atlas rear wheel; it's much stronger because there are three cone shaped lug nuts that center and tie the break drum to the wheel; you have to change the offset slightly, not the same on an Atlas as on a Commando.
Here's a thread on this: one-piece-rear-wheel-spindle-t3319.html Have a look through this first, and also do a search because there are more threads on this subject.
I wanted to do this conversion as a safety measure, but haven't got around to it yet. If I come across a wheel with a rear disc that I can modify, that might be better for my purposes.
Rather than go into too much detail here, have a read of the thread and see if it's for you.
Dave
I wanted to do this conversion as a safety measure, but haven't got around to it yet. If I come across a wheel with a rear disc that I can modify, that might be better for my purposes.
Rather than go into too much detail here, have a read of the thread and see if it's for you.
Dave
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I asked Michael Tagilari for his NYC apartment method as he was first I'd heard of this safety feature and never gave it another thought until my slow poke buddy Wesly passed Ms Peel doing 90 my going 115 to catch me before my tire blew from rubbing on fender edge d/t lose of axle clamp force when it broke.
I was standing on pegs finger tips on bars so a blow ouy might of hurt us.
Weakest link in this procedure is thinning the metal of swing arm slots.
Until this conversion done - consider deeply - serious safety wiring or such the RH axle up tight against the adjustor, as I've never ever heard of a brake lever cable let go to pogo a rider but brake safety spring is widely worn, who but me secures their RH axle for safety?
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I'm not actually sure I ever DID a detailed post, but just a general e-mail. The only way to fully explain it would be a full-fledged article illustrated with pictures. I'd like to do one but I have to find the time, and also find another Commando with its rear end apart for the "before" pictures.
Here is basically how it's done. You need is a metal-turning lathe with a 3-jaw chuck but it doesn't have to be a particularly good one. (A high-precision drill press would also work if you know how to use it, but centering the parts on the table would be a real pain). You basically put each part in the 3-jaw chuck and drill it out to 17mm. On a small lathe like my 7x10 minilathe, this requires step-drilling (starting with a small drill and gradually increasing the size) because 17mm is a big-ass drill). On some parts, the enlargement is hardly noticeable, and on others (like the dummy axle) most of the part gets taken away, and it turns it into a spacer. You don't have to drill the actual bearings, because Norton used 17mm bearings in the stock rear axle and sleeved them down to the axle size.
My rear axle is from a Honda CB 350, but Ben English said many bikes of that era used 17mm rear axles. After you get the axle, you file the slots in the swingarm larger with a large file. This is easier than it sounds, because you make a test-bar on the lathe -- a rod a few inches long with steps in it, starting smaller than 17mm and working up to it. This is not high-precision work, because you WANT a little play so the axle will go in easier. Then you have to make spacers for both ends of the axle that the adjusting screws can ride against. Again, this is an easy job with a metal-turning lathe.
The only part of the job that's not easy is modifying the speedo drive. The hole in the middle of the steel "top hat" spacer in the stock speedo drive is 9/16" to fit the stock axle, and the spacer then fits into a larger hole on the speedo drive. You can't drill out the spacer to 17mm because there isn't enough of it. Instead, you have to make a bigger one that's 17mm on the inside, then bore the body of the speedo drive to accept its outside diameter (which can be anything you want, within reason). This is the trickiest part of the job, but it would still be easy for a hobby machinist with a lathe because only the 17mm inside hole is a critical size, and that only has to be drilled 17mm, not bored or reamed.
Post this to the Norton Forum (which I just joined, BTW), and if any questions come up I can answer them.
Mike
I was standing on pegs finger tips on bars so a blow ouy might of hurt us.
Weakest link in this procedure is thinning the metal of swing arm slots.
Until this conversion done - consider deeply - serious safety wiring or such the RH axle up tight against the adjustor, as I've never ever heard of a brake lever cable let go to pogo a rider but brake safety spring is widely worn, who but me secures their RH axle for safety?
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I'm not actually sure I ever DID a detailed post, but just a general e-mail. The only way to fully explain it would be a full-fledged article illustrated with pictures. I'd like to do one but I have to find the time, and also find another Commando with its rear end apart for the "before" pictures.
Here is basically how it's done. You need is a metal-turning lathe with a 3-jaw chuck but it doesn't have to be a particularly good one. (A high-precision drill press would also work if you know how to use it, but centering the parts on the table would be a real pain). You basically put each part in the 3-jaw chuck and drill it out to 17mm. On a small lathe like my 7x10 minilathe, this requires step-drilling (starting with a small drill and gradually increasing the size) because 17mm is a big-ass drill). On some parts, the enlargement is hardly noticeable, and on others (like the dummy axle) most of the part gets taken away, and it turns it into a spacer. You don't have to drill the actual bearings, because Norton used 17mm bearings in the stock rear axle and sleeved them down to the axle size.
My rear axle is from a Honda CB 350, but Ben English said many bikes of that era used 17mm rear axles. After you get the axle, you file the slots in the swingarm larger with a large file. This is easier than it sounds, because you make a test-bar on the lathe -- a rod a few inches long with steps in it, starting smaller than 17mm and working up to it. This is not high-precision work, because you WANT a little play so the axle will go in easier. Then you have to make spacers for both ends of the axle that the adjusting screws can ride against. Again, this is an easy job with a metal-turning lathe.
The only part of the job that's not easy is modifying the speedo drive. The hole in the middle of the steel "top hat" spacer in the stock speedo drive is 9/16" to fit the stock axle, and the spacer then fits into a larger hole on the speedo drive. You can't drill out the spacer to 17mm because there isn't enough of it. Instead, you have to make a bigger one that's 17mm on the inside, then bore the body of the speedo drive to accept its outside diameter (which can be anything you want, within reason). This is the trickiest part of the job, but it would still be easy for a hobby machinist with a lathe because only the 17mm inside hole is a critical size, and that only has to be drilled 17mm, not bored or reamed.
Post this to the Norton Forum (which I just joined, BTW), and if any questions come up I can answer them.
Mike
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Probly irelephant ,
but
Once people threw Honda 750 rear Wheels in , as they considered the cush drive superior.
Saw one or two around 1977, presumably the CB 750 wheel,as it was all that was around then.
One had a alloy rim.
The Triton Domiracer thing I built had a 67 Triumph Twin swing arm,
The Triumph Conical Hub is said to Be the magnesium MANX one done in Aluminium.
The 75 wheel has a lid type bearing retainer, hub with male thread.
The earlir one with screw in bearing lock could crack ,so latter is preferable.
Then got the Large heavy Triumph non-Q.D. axle, the sizes matched the bearings and spacer,
except for the inner spacer I.D. , Put a large drill through it in an engineering shop,
and the whole contration fitted together rather well.
Had short roadholders , external springs, and Drum Commando Front Brake,
AM4 linings and progressive springs both ends.
BUT,
LOSEING the CUSH DRIVE , unless youve fitted a BELT PRIMARY is a no-no,
as is not aving one in the primary drive, prefeably on the crankshaft ! :lol:
but
Once people threw Honda 750 rear Wheels in , as they considered the cush drive superior.
Saw one or two around 1977, presumably the CB 750 wheel,as it was all that was around then.
One had a alloy rim.
The Triton Domiracer thing I built had a 67 Triumph Twin swing arm,
The Triumph Conical Hub is said to Be the magnesium MANX one done in Aluminium.
The 75 wheel has a lid type bearing retainer, hub with male thread.
The earlir one with screw in bearing lock could crack ,so latter is preferable.
Then got the Large heavy Triumph non-Q.D. axle, the sizes matched the bearings and spacer,
except for the inner spacer I.D. , Put a large drill through it in an engineering shop,
and the whole contration fitted together rather well.
Had short roadholders , external springs, and Drum Commando Front Brake,
AM4 linings and progressive springs both ends.
BUT,
LOSEING the CUSH DRIVE , unless youve fitted a BELT PRIMARY is a no-no,
as is not aving one in the primary drive, prefeably on the crankshaft ! :lol:
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- Sep 15, 2005
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I have a one piece axle in my bike , made pretty much as Mike says. The honda axle is very hard and tough to thread.( I sent mine out to a local machine shop) Because nortons were built with a couple different rear end configerations The spacers need to be the same as the one on the dummy axle and speedo drive for your bike. I found the honda rear axle sdjusters much better than the 850 Norton sheet metal ones and they can be fitted with out much fuss.
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I built a strong 750 race motor for Jim Siemer who then broke several 2 piece axels. Then he drilled through and installed a one piece axel. He then won the AHMRA championship somewhere in the mid 1980s. I've since made the same odification on my own street bike and just use the tac to determine MPH.
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Yes, I should have said that the downside of the Atlas wheel is that you lose the cush drive.
Not that those six little pieces of plastic really do much. Even with our nominal "cush drive," if you jump off a curb with the power on, you'll likely wreck your trans.
Not that those six little pieces of plastic really do much. Even with our nominal "cush drive," if you jump off a curb with the power on, you'll likely wreck your trans.
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Ok, My bike is a morphordite, a 73/74 with a 75 swing arm & disc brake and an Old Britts removable sprocket carrier so my dimensions will not help anyone.I also had to make a spacer for the speedo drive to the Old Britts sprocket carrier.
I Querried Frank Forster prior to doing my axle and he gave me basically what MikeT said minus all the home lathe stuff.
Quote, Frank F (5 march 2010)
It was quick & easy, using an existing Japanese 17 MM axle that I found somewhere and turned up one steel bushing on my lathe.
In today's BI Mike T reports that he made an axle from a Honda CB350 (Same in Honda CB 450)
The RH end of the LH stub axle has a large dia.(Norton) from which you get the dimensions of the bushing that must be made.
The axle slot in the left hand swing arm tail must be filed wider for the larger axle, and the axle hole in the speedo drive box must be opened up.
For tire change, the axle is pulled out from the left,leaving enough of itin place to suport the sprocket.
I turned a thread on the RH end of the new axle to take 5/8" fine thread nyloc nut. Big mistake,as the new nut shook loose on the freeway, allowing the axle to move out of the RH swing arm slot, there by locking up the rear wheel@75 MPH, I Immediately replaced with a cross drilled hole & castellated nut retained by a cotter key. No other problems ..
Cheers Frank
I'll add,
The Honda axle is very hard, you will not be able to thread it with a die.
If you bike has the flimsey chain adjustors (850) try to fit the heavy duty Honda ones.
Keep the length of the new axle a little long so that you have enough extra length to drill & pin to hold the nut on.
The 17 MM axle will fit the bearings fine.
I Querried Frank Forster prior to doing my axle and he gave me basically what MikeT said minus all the home lathe stuff.
Quote, Frank F (5 march 2010)
It was quick & easy, using an existing Japanese 17 MM axle that I found somewhere and turned up one steel bushing on my lathe.
In today's BI Mike T reports that he made an axle from a Honda CB350 (Same in Honda CB 450)
The RH end of the LH stub axle has a large dia.(Norton) from which you get the dimensions of the bushing that must be made.
The axle slot in the left hand swing arm tail must be filed wider for the larger axle, and the axle hole in the speedo drive box must be opened up.
For tire change, the axle is pulled out from the left,leaving enough of itin place to suport the sprocket.
I turned a thread on the RH end of the new axle to take 5/8" fine thread nyloc nut. Big mistake,as the new nut shook loose on the freeway, allowing the axle to move out of the RH swing arm slot, there by locking up the rear wheel@75 MPH, I Immediately replaced with a cross drilled hole & castellated nut retained by a cotter key. No other problems ..
Cheers Frank
I'll add,
The Honda axle is very hard, you will not be able to thread it with a die.
If you bike has the flimsey chain adjustors (850) try to fit the heavy duty Honda ones.
Keep the length of the new axle a little long so that you have enough extra length to drill & pin to hold the nut on.
The 17 MM axle will fit the bearings fine.
Have a look at the design of a typical Japanese wheel spindle. It is not just made out of tough steel, the threads are rolled (like spoke threads) for extra strength.
I remember Jim Comstock advising not to cut the threads on a wheel axle but I think he mentioned that he managed to find some of the right length.
I have seen spindles on race bikes cut to length at the hexagon end, threaded and a nut screwed on, and then welded in place. The weld is then cleaned up on a lathe. The material is too tough to cut with a die. Threads would be cut on a lathe. Would an engineer care to comment on this approach?
I remember Jim Comstock advising not to cut the threads on a wheel axle but I think he mentioned that he managed to find some of the right length.
I have seen spindles on race bikes cut to length at the hexagon end, threaded and a nut screwed on, and then welded in place. The weld is then cleaned up on a lathe. The material is too tough to cut with a die. Threads would be cut on a lathe. Would an engineer care to comment on this approach?
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