Is this camshaft good to install?

Hi fellow Norton fans. I just need some advice on a camshaft I have purchased.
The camshaft is chilled iron camshaft circa 1970.
After receiving the item, I am worried about the quality of the lobes. The cut on the lobes are jagged.
So is the cam fine to install, or should I return ?
My knowledge is limited, so I’m going to rely heavily on the advice I receive from this magnificent forum.
The bike is Mk2a. Cheers.

The edges are fine as the followers dont run there but there is one lobe with what looks like scuffing / a groove towards the centre of a lobe - 3rd picture.

First instinct purely from that photo is to return.

georges126 said:

Hi fellow Norton fans. I just need some advice on a camshaft I have purchased.
The camshaft is chilled iron camshaft circa 1970.
After receiving the item, I am worried about the quality of the lobes. The cut on the lobes are jagged.
So is the cam fine to install, or should return ?
My knowledge is limited, so I’m going to rely heavily on the advice I receive from this magnificent forum.
The bike is Mk2a. Cheers.

Click to expand...

I think the scuff that you refer to , is residual from a sticky label. I’ve removed the glue and taken another picture. I think it now looks okay.

You are good to go, based on the surface finish where no machining took place that cam is likely to be a Chilled Cast cam out of Newmans. In which case make sure you use the much lower torque figure for the end nut or your cam will crack.

Grandad said:

The edges are fine as the followers dont run there but there is one lobe with what looks like scuffing / a groove towards the centre of a lobe - 3rd picture.

First instinct purely from that photo is to return.

Click to expand...

I see a low spot in the casting, that didn't clean up when ground. It will pose no functional problem.

Spot on , a Newman cam. Thanks for your wisdom.

Sticky label ... excellent news ........... new photo makes it look perfect

I admit I have no experience with changing Norton cams/tappets but I have a lot of experience with OHV V8's so I'm posting this as much an enquiry as a possible caution.

Are you re-using the old tappets that were used with a different cam? In automotive cams/tappets, using 'used' tappets on a different cam or positioning them on a different lobe of the same cam can cause rapid camshaft wear/destruction. I mean seriously rapid - as in removing most of the lobe in a hundred miles. Heck, I have also seen cams destroyed literally in minutes if proper cam break in procedures are not followed. It is often stated that if an OHV tappet still has a convex face, it can be used with a new cam though I would never do that and don't know of any performance shop that would.

FWIW, The tappet face remaining convex or going concave (which they typically do) is of no consequence at all if a used cam and the same lifters are removed/replaced in the same position in the same engine since the lobe/lifters have worn-in with each other.

MexicoMike said:

Are you re-using the old tappets that were used with a different cam? In automotive cams/tappets, using 'used' tappets on a different cam or positioning them on a different lobe of the same cam can cause rapid camshaft wear/destruction.

Click to expand...

Quite right, always fit new followers with a new cam unless you have the old followers reground. Mark them so they can be replaced in the correct positions after a future strip down.

and Newmans do a vg follower regrind service!

Thanks for the tip, I will do that.

New lifters or regrind. Lots of assembly lube on cam. Don't let the engine sit and idle during the first half hour so that splash lubrication keeps the cam oiled. Usually I start the bike and let it run at 2000+ rpm for five minutes. Shutoff and let cool down. Retorque head bolts and set valve lash. Restart, check timing, rough adjust idle and start riding, keeping rpm between 2 and 4 thousand. After a hundred miles retorque and set lash again. At this point most of the major break in has occurred. Fine tuning the idle can wait until you have some miles on the bike.

Should be fine and good to go .
I've seen 2 cams with lobe wear on the drive ( left ) side in my younger days of teardowns . Don't know why the left side wears out first .
But you are good to go .

georges126 said:

Hi fellow Norton fans. I just need some advice on a camshaft I have purchased.
The camshaft is chilled iron camshaft circa 1970.
After receiving the item, I am worried about the quality of the lobes. The cut on the lobes are jagged.
So is the cam fine to install, or should I return ?
My knowledge is limited, so I’m going to rely heavily on the advice I receive from this magnificent forum.
The bike is Mk2a. Cheers.

Click to expand...

It's a bit late for the OP, but for anyone else who's installing a used (or maybe even new) camshaft, it might be worth checking it for straightness. I've had two recently, one was bent between the journals - likely the result of some other failure - and the other appears to have been manufactured with the sprocket seat and nose (outboard of the timing side journal) offset by 0.005" (resulting in 0.010" run-out).

The best way to check might just be to fit the cam in the crankcases before the crankshaft, sealant, etc. If it fits and turns freely it is probably straight between the journals. Then check the runout at the sprocket seat and nose. Anything more than a thou or two of run-out will cause problems with the timing chain and/or the sealing of the points compartment.

It's frustrating to find you have a wobbly camshaft end, after you've got the engine back in the frame.