Axle break

Halfway back from Davenport to Alice's Restaurant I joined the broken axle club. Since I noticed the bike felt funny, I slowed down so God rewarded me with a fairly large place to aim my bucking bronco. Went for 15 miles at 12 to 15 mph and not one person honked or got mad. Nice, made me feel better.

I would like a one-piece axle. I believe Madass140 makes one. Are they easy to install? Are they holding up?

Hi, I have one Madass axle, and put it the other way round ( going into the swingie through the left side ), as I imagine it will be easier next time I need to take out the wheel while letting the chain in place (it's a cush drive hub), a bit fiddling when alone but when done it's OK , and no more frightening rodeo sessions when you break that axle!!!

marinatlas said:

Hi, I have one Madass axle, and put it the other way round

Click to expand...

Did the same with madass's axle and came in handy when I had to fix a flat last week (snagged a drywall screw on an otherwise pleasant ride).

You might waste a lot of time waiting for a broken one-piece axle report...

I'm guessing the failure was at the end of the threaded section?

Diablouph said:

Halfway back from Davenport to Alice's Restaurant I joined the broken axle club. Since I noticed the bike felt funny, I slowed down so God rewarded me with a fairly large place to aim my bucking bronco. Went for 15 miles at 12 to 15 mph and not one person honked or got mad. Nice, made me feel better.

I would like a one-piece axle. I believe Madass140 makes one. Are they easy to install? Are they holding up?

Click to expand...

From the submitted photo, I see no break. Only rear axle pulled out a few inches. Is the break at the "dummy axle" or the axle itself? Or am I looking at this incorrect?

The photo doesn't show the actual break.

I have pictures of what the radioactive half life broken hidden end of the long axle looks like and a few exactly like this one stickng out one when discovered on the fly. Last engaged thread valley in dumbass axle lets go. The danger is the RH free of clamp force lets it slide back in slot d/t chain pull, surprisingly unnoticed even with tire rubbing away swing arm to smoke like a fire or getting sliced by fender edge, its hardly noticed at hwy speed. My far from home 1st aid is hose clamps, or tape or wire to hold it froward and inward, then can ride full hwy speed [light throttling steady steering] no porblemo, but getting below 10 mph it flops like a flat tire till stopped or above 12-15 mph. In gusty or rough roads with good cargo its more touchy to stay steady and not induce THE Weave aka The Hinge. The solid SS or rustable steel axle should prevent the radioactive fissions we hear of here about twice a year so implies there's like 4 others we don't hear of as by far most Cdo owners are not online with Norton forums. i've inquired at half dozen rallys if they were online or heard of hobot - ~ 90% said nope. I am pleased to hear its not bad to remove wheel for road side flat repair, big sales point for me. It ain't factory part numbered for Trixie and it won't fit Peel's new rear - otherwise its a no brainer to avoid the fall out lurking ...

Riding with angled loose rear tire from axle fissioning 2 Combats now, is very informative and puzzling on what is doing what to steer a motorcycle. I've put on 50+ miles on Peel loaded to the gills and 60+ miles on unloaded Trixie riding a two parted axle barely held in somewhat. Wonder if a mag flux could tell ahead of time on who will be next? Definitely more common safety issue than the brake cable breaking to be caught by the peddle spring retainer upgrade, if ya got that unused feature installed.

Bob Z. said:

I'm guessing the failure was at the end of the threaded section?

Click to expand...

That's my guess. I'll know more when I disassemble everything.

Two vietnamese students from Stanford were nice enough to give me a ride 20 miles to my car with my trailer. I didn't mention I helped shell their country 45 years ago.

Diablouph said:

Two vietnamese students from Stanford were nice enough to give me a ride 20 miles to my car with my trailer. I didn't mention I helped shell their country 45 years ago.

Click to expand...

You do what you gotta do, I remember hitchhiking from Monterey to Salinas to Raber's to get parts for my BSA and always being given a ride by a bunch of 'hippies', but they always treated me fine, but I worried the whole way since I had the Army buzz cut. Paranoia city.

Dave
69S

Glad you survived unscathed. I am not at all impressed with that rear axle set up on Commando's. A one piece is safer, in my opinion. On my bike the slot in the right side of the swing arm where the axle passes through is wider than the diameter of the axle. The drive side dummy is a perfect fit. Seems that the right side can move up and down. Not good. Wheel can flop. So, previous owner has tightened the axle up mega tight to prevent problem. But is the axle at the top edge or bottom edge ? Is wheel square if the axle is on the bottom or top edge ? Wobble and weave at speed ?
Another thing to consider; is the thread on the long axle BSW or UNC ? UNC is pointed at root and crest of thread, stress risers. BSW is rounded in those places, less of a stress riser. Is there a mix of thread's in there.
It may be that there is a big build up of crud in the hole in the dummy and the long axle is trying to compress it all in there. Or to much rust and crud on the thread choking the threads. Or the threads on the long axle have been damaged at some point making it hard to tighten.
Load up those stress risers men !
If owners have a sloppy swing arm slot and shot rubbers in the 'cush drive' they may have reefed up the long axle with too much grunt to squeeze to all together. A bit of fatigue on the shaft end of the thread and you are in deep shyte.
Hope you resolve the problem safely mate.

Yeah, I'm waiting on the Madass single axle for the 69/70 without the cush drive. I managed to ride my bike around for a while (on the ride home) before I knew it without the 3 "nuts" that hold the wheel on the hub. I hardly noticed it, but it was early on and didn't seem to damage anything. If the nuts had been there and loose, it may have damaged it. For sure I don't really crank down on tightening the long axle into that stub, I give it 70 ft-lb and that's it.

Dave
69S

I'll have to do some checking , the early Commando boltup axle is probably different lengths etc that the boltup Atlas, I assume the early Commando swingarm is the same width as the later ones but different from Atlas even though they are both boltups.

I had mixed in the past the rear wheel , and I can say both early and late Cdo swingies are the same width, same for Atlas BUT the dummy axle is slightly diiferent in the way of the flat which goes into the swing slots are longer on Atlas than Cdo ...............

I had mixed in the past the rear wheel , and I can say both early and late Cdo swingies are the same width, same for Atlas BUT the dummy axle is slightly diiferent in the way of the flat which goes into the swing slots are longer on Atlas than Cdo ...............and the OD part which goes into the sprocket drum.....

Long axle always breaks off at last thread valley exposed on RH side of dumb axle. The threaded end left in dumb axle should be finger loose to remove. There are at least 3 sligtly different dumb axles issued for Commando's, each slightly alterting where the drum seats in line with chain run or how close the wheel hub mates into the cushions when nipped up.

Thanx for the pics Hobit.
Curiouser and curiouser.
On my bike the bearing in the brake hub was a rusted mess. It wasn't operating as a bearing being unable to support any load in it's lamentable state.
The previous owner, a big fat bastard at about 400 lbs, must have ridden on some dirt roads and never gave the item a second thought. Evidently.
The brake drum was being pulled all over the place by the chain but as the brake drum was full of grease the brake wasn't working which was also a nice scenario. Those tiny paddles that are supposed to be some kind of shock absorber were moving in and out of their formally rubberised slots. Wobbling all over the place. There were nice shiny polished areas on the hub and drum as witness marks to the adventure.
This is not safe engineering, in my opinion.
All that was holding the rear wheel together, and on the bike, was a lose long axle. Sure the dummy was tight, only about 1000 tons per sq in. Ye god's !
The hub bearings were shot as well.
Maybe someone out there could redesign a whole new rear hub and brake drum sprocket thing, to original appearance, that would eliminate all these dangerous problems.
None of the many Japanese bikes I owned had any problems what so ever with the rear wheel assemble and or brake or sprocket.
I'm now seriously considering putting on a set of period Morris mag's. And a one piece axle.
'Wagon Wheel's' anyone ?

Throb, ya got to come to grips Commandos were only considered a stop gap bike by a company going under with bean counter pulling the cream off for the management. I do believe the rear drum bearing going dry and slack help beat the snot out of the last exposed thread stress riser. Throw on more mass over shocking surfaces its like spring time sunshine nuetrinos polarity on nuclear decay rates, [half life] speeds up the random axle fission events.

Axles like cables and tires eventually should be renewed, maybe in 20 yr or 25,000 mile cycles or just wait till needed?

My first one popped on return of over loaded trip on know dry loose bearing w/o any grease to pack in 1000 miles from home by then, so after runing over my diaphragm spring compressor at 90+ mph standing on pegs to cool off in July over heat swollen cement pads raised tar seams axle broke though I felt nothing at all so kept hard on it to see my buddy wiz by like 115+ to flag me over to notice a bit of wobble so got off to see whats up and he's pointing behind me, so I turned to see a huge dense blue/while cloud over a mile long leading up to Peels rear tire. I got wide eyed of course to peer at tire to see fender almost sliced through. There is a God which told his Son never copilot with hobot, so the Devil keeps me here for laughs. On that note the rear blow outs I've had at near the ton were also hardly detectable till slowing to pitch into a turn...

Second time was on new built Trixie Combat on a parking lot to learn peg drag tight circles till felt perfect balance control sink in so got bores so intended to induce a phase 4 hi side leap to toss from full LH lean to full RH lean when axle popped and took up the frame rebound i needed to lift off, thought it was a flat tire until finally noticed the axle sticking out like the photo staring this thread.

I abused mine and on Peel it actually caused her to land upside down, twice in a a row from 5 ft up on a board walk but ain't gonna happen that way again thankyou. I've read over a dozen fractures thrill rides but not a single crash so its not as horrific an event as it sounds. I much more fear a slow leak in front than busted axle. A rear flat is rather harder to ride on than broke axle.

So as I was saying either take em as they are &or go as hog wild as a Peel eliminating any everything Norton but the TS cover, the isolastics and the sound. Peel for instance now has 19mm one piece drilled hollow axle with substantial cushions. There are a number of lessor solutions available. Peel will get her turn to be on top of me again so must be hobot proof.

Ok Hobbie, me old mate,
I actually do know that the Commando was a stopgap thing.
I like to vent occasionally and slag off the poor design considerations involved. Particularly potentially dangerous components.
The bike I own was previously owned by a fat bastard who is an engineer by trade. He was, and still is, too damn fat to work on the bike despite him saying that he did. So much neglect and damage done to the bike by the original Canadian owner too.
I don't have the time and resources just now to get into designing modifications for this beast but time will come when I do. I can use MastrerCam and other CNC program's, I can set up and run CNC machinery so doing that kind of thing is a doddle for me. I've done it since about 1984.
First on the list is a horizontally split crank case with 3 plain mains, electric starter where the mag used to be, balance shafts and roller bearing cam. Wouldn't that be nice ?

Well shoot the yogi's saints etc tell us our soul comes and go but I don't think so any more so better make the best trip through the first and only time so yeah man create a new type Commando to knock your-our socks off, I sure am. I traded working for good money for the time of my life this last 15 yr and got it in spades but extended the time its taken to get my Ms Peel going and as bullet proof as possible. Machinist maddass has come up with SS solid axle which made me recoil at 1st on its SS d/t SS engine bolts failing but now realize its stronger than the factory half life stress riser so can solve risking a fracture. After feeling how 'easy' to control a busted axle is, all's we'd need to avoid super motard antic skills trying to get home is a safety clamp to hold axle against the adjuster and from worming out. In the end a real Commando has a limited flight envelope - exceed it at your own risk or trash out the Norton parts and join my fantasy flight.