High mileage

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Any weird things you have experienced on high mileage Commandos?
High mileage
 

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Impressive numbers , do you know if accurate of distance travelled ?
 
At 26,000 miles I don't perceive anything weird. But then I suffer from periferal neuophony (or something like that)
 
They do it, mine I have own since new 1976 and was my everyday rider for most of its life till 8 years ago now my Triumph Thruxton has taken over that duty but I still ride the Norton, I have average between 6k to 10k miles each year has only had one major rebuild when converting it to the Featherbed frame back in 1980 to 83 and has had another minor rebuild back in the late 2000 when I had to replace the crank cases, I still run the original valves although head has had 2 full rebuilds with porting and guides and major repairs from the first head rebuild from a stuff up from the so called head expert and has had a few upgrades in the 46 years of ownership, so my Norton has well over 160k miles on it, its showing its age now but still pulls like a train, its my HOTROD Norton, its no show pony, but that's the way I like it, been very reliable to me because I do the maintenance when its needed, fix things that wear out or break, but for engine wise has never let me down in the 46 years, I still run the original clutch plates and GB has only been rebuilt once in 1979 with the dreaded lay shaft bearing failure but the kick start gear has been replaced and 4 KS pawls and a broken KS shaft in that time and clutch centre, it survived a major fire back in 83 when not long after getting it back on the road with the Featherbed conversion and I was on it at the time it caught fire.
I don't keep mileage as original speedo was damaged in the fire back in 83 but was rebuilt 8 years ago with the taco, been running a Triumph Smiths speedo that was given to me back in 83 after the fire, I still run the original speedo drive and cable from new because they get maintained, my Norton might look old but its one of the best maintained bike I have ever owned, built by my own hands back in the early 80s, its had its share of time off the road from owner injuries and major upgrades in the 46 years I have owned it, and when out on it, it still gives me a big smile on my dial and it be with me till the day I leave this world.

Ashley
High mileage
 
Gene Austin in the local Norton club told me strange things occur at high mileage, but that was 30 years ago. I don’t recall what he mentioned. My 60K is approaching “high”. Looking for original Commando owners with mileage closing on 100,000.
 
minor rebuild back in the late 2000 when I had to replace the crank cases

That is MINOR?....good lord!
 
I bought it from Phil Radford in 1997. It had 20470 miles then and I’m fairly confident that was accurate. The following 40,000+ miles are mine.
I would feel very confident buying it from Phil.Also glad to see that odometer reading.Good for you!Have you had the lower end apart?
Mike
 
My late uncle was at nearly 200,000 miles on his '74 Mk 2 when he was killed in an accident in June of 1993. He was the local Norton mechanic / guru in South Western Ontario. Wish he was still here to ask what he had to do to it to get that kind of mileage out of it....
 
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I would feel very confident buying it from Phil.Also glad to see that odometer reading.Good for you!Have you had the lower end apart?
Mike
The bottom end was rebuilt in ‘97-‘98 so has 40,000 miles and seems in very good condition. Top end was rebored to +.040” at that time. The whole machine was restored at that time as it sat for 20 years and was in three lumps. These are normal wear points. What I’m thinking is wear on things like wheel and engine castings, frame sections…etc.
 
My late uncle was at nearly 200,000 miles on his '74 Mk 2 when he was killed in an accident in June of 1993. He was the local Norton mechanic / guru in South Western Ontario. Wish he was still here to ask what he had to do to it to get that kind of mileage out of it....
That’s what I’m looking for. Did your uncle mention any worn out castings or frame sections?
 
That’s what I’m looking for. Did your uncle mention any worn out castings or frame sections?
No, do not recall him mentioning anything like that. There are 2 things that I do remember - he had the exhaust port threads repaired and the Amal carbs sleeved. The only other mod I remember is that he put a Lucas Powerbase alternator on when they were first introduced.

He always ran points - he had installed so many Boyers over the years on other's bikes, he had an endless supply of AAU's and points plates - lol.

I am sure he overhauled the top end of the motor a couple of times, but being a Norton mechanic, it was like doing a tune up for him - lol.
 
77,000 plus on Mitzi (my Mk3) Had to repair the g/box cradle when i got her as the bottom lefthand 'ear' had broken off (that the bottom engine bolt goes through) At the same time fitted slightly oversize engine studs through reamed holes fastening the engine to the cradle. This is one of the procedures outlined in the tuning notes published by Norton back in the day. This stops the engine jiggling around in the cradle and helps keep the g/box alignment to what it should be. Did the same to the g/box (made and fitted close fitting studs), with the plain section long enough to span the cradle (the standard g/box and engine studs/bolts have the thread bearing on the cradle and engine alloy at one end allowing/promoting the hole to wear bigger)
 
77,000 plus on Mitzi (my Mk3) Had to repair the g/box cradle when i got her as the bottom lefthand 'ear' had broken off (that the bottom engine bolt goes through) At the same time fitted slightly oversize engine studs through reamed holes fastening the engine to the cradle. This is one of the procedures outlined in the tuning notes published by Norton back in the day. This stops the engine jiggling around in the cradle and helps keep the g/box alignment to what it should be. Did the same to the g/box (made and fitted close fitting studs), with the plain section long enough to span the cradle (the standard g/box and engine studs/bolts have the thread bearing on the cradle and engine alloy at one end allowing/promoting the hole to wear bigger)
Yep it's worth doing the oversize studs I did the same on my 750 when I built it
 
At the same time fitted slightly oversize engine studs through reamed holes fastening the engine to the cradle. ... Did the same to the g/box (made and fitted close fitting studs), with the plain section long enough to span the cradle (the standard g/box and engine studs/bolts have the thread bearing on the cradle and engine alloy at one end allowing/promoting the hole to wear bigger)

Is the threaded section serving as bearing in the cradle?? Wow. What a bummer by NV. Thanks for raising awareness. A new cradle will be fitted to my Mk3 build, and I will certainly follow your example.
May I ask what size you chose for the g/b bolts? How did you ascertain tensile strength requirments specified by N-V were met?

- Knut
 
minor rebuild back in the late 2000 when I had to replace the crank cases

That is MINOR?....good lord!
Well to me pulling the motor down isn't really that hard the only thing I did was new set of crank cases and new main bearings the rest of the motor was just pulled apart rod and pistons stay on the crank, head wasn't touched or barrels didn't get touched as the motor had a rebuild a few months before the crankcases were replaced, that's was when I had the old crank case welded up had hair line cracks around the main seal area, but the it started to leak again why I decided to get another set of crank cases, so to me yes a minor job, a full rebuild is a major job to me.

Ashley
 
A clubmate just rebuilt his 73 850 with 128,000 miles.
I'm going on a 4 day trip with him in a couple of weeks.
He had no major problems getting to 128,000. The top end received a rebore and 1 st oversize pistons at about 65,000.
At 128,000 he felt he should do the complete engine even though it was mainly the top end that was tired.
The crank and superblends all looked great but in the end he reground the crank and installed new bearings.
Same with the cam and lifters, they had only a small amount of wear showing but he treated it to new items anyway.

Glen
 
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