Norton crankshaft opinion

[ronan]

I picked up a Norton commando crankshaft years back for a project, anyway the guy i got it off said he had the mainshafts hard chromed and ground back to standard size as the fit had got slack. Its a nice job, but in some of the corners the chrome has chipped and i am wondering if you would consider the edges on the chrome a stress raiser ? I don't want to build an engine only for it to break up on me.

 

[cocker]

If it were mine I'd stick it in , and forget about it .

 

[brightspark]

same here. its only surface on the chrome

 

[Bladevane]

I would probably consider spallation of the chrome plating a more serious potential issue than the edges being a stress raiser. Maybe the edges were not quite as clean as they should have been to ensure correct bonding of the chrome plating.

 

[Chris Stevens]

Will be fine as long as you arent going to race it...................

 

[brightspark]

Will be fine as long as you arent going to race it...................

will be fine if he does just pay and get the engine fully balanced. I built my Norton engine and can pull the puds out of it no problem

 

[ronan]

will be fine if he does just pay and get the engine fully balanced. I built my Norton engine and can pull the puds out of it no problem

I'd not have a big parallel twin unless it was dynamically balanced. I got the 500 done by srm in Wales and it was like a swiss cheese when i got it back. Worked though, a lot of the shakes had gone.

 

[ronan]

Will be fine as long as you arent going to race it...................

Well there is always the traffic light Grand Prix, and none of us are immune when some boob throws down the gauntlet !

 

[brightspark]

Well there is always the traffic light Grand Prix, and none of us are immune when some boob throws down the gauntlet !

love it specialy when some prick pulls level with u revving the titts out of his motor and looks over at u and u just look out of the corner of your eye so he don't notice u looking get the revs up constant and let the clutch out and go for it leaving him standing its great fun and practice when I used to stockcar race

 

[mechman]

I'd not have a big parallel twin unless it was dynamically balanced. I got the 500 done by srm in Wales and it was like a swiss cheese when i got it back. Worked though, a lot of the shakes had gone.

In the early 70s I got my bonny crank balanced by greenwood cranks, it came back with the redrilled fly wheel balancing holes practically opposite the factory ones, In fact it was that good I could see out the mirrors at 60mph, How good is that

 

[mechman]

I picked up a Norton commando crankshaft years back for a project, anyway the guy i got it off said he had the mainshafts hard chromed and ground back to standard size as the fit had got slack. Its a nice job, but in some of the corners the chrome has chipped and i am wondering if you would consider the edges on the chrome a stress raiser ? I don't want to build an engine only for it to break up on me.



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Ronan unless you're going to be seriously competitive with it I don't think it would matter one jot,I think its just peace of mind but if the tolerances are ok let it go.

 

[ronan]

Mechman, it was just the edges are sharp and i was worried they would be a stress raiser, especially on that long thin alternator part of the shaft.

 

[ronan]

Royal Oilfield were the only factory to dynamically balance their cranks. The larger twins were supposed to be better than anything else of similar size.

 

[mechman]

Royal Oilfield, That's a belter,