Rocker arms - sorry guys something to worry about

I think the highest mileage bike I have seen was about 8000miles and it was a total oil pump failure that caused top end and tappet issues. Google valve lash caps and you see what they are.

Oil pressure can be improved by removing the inline filter, checking the oil pump for smooth operation, checking the intake line for kinks or any out of round condition. We had one bike that had slag in the oil tank outlet(oil pump inlet hose side) that kept oil from fully running to pump causing erratic readings. I really implore anyone read this to make a guage to check you oil pressure. The dummy light doesn't come on until the pressure is really low and even then it might not come on as we have found out.
If the pump turns out to be the culprit, what can be done?
 
make a guage to check you oil pressure
Mate, have you got a "this is one we've done" or a link to a "buy it now"?

I've looked at doing this before, but wasn't confident enough in my knowledge of the oil system to trust that I wasn't going to do something that made things worse......
 
I looked at the adjusters because after 13500 miles I can recognise an unusual noise and just had a really weird hydraulic lifter issue with one of my cars. Really does sound like anything over a few thousand miles needs checking. Ideally oil pressure as well. And make sure that filter is clean.
Thanks City Garage the valve stem caps will save a shed load of work. Unfortunately it seems it’s illegal to possess these in the uk so nearest place to buy is Germany.

Shaft on the one inlet is damaged where the rocker steel polished it others are max .02mm worn as there was no steel to steel contact. Will replace though.

Like I said I love this community.....
 
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I think the highest mileage bike I have seen was about 8000miles and it was a total oil pump failure that caused top end and tappet issues. Google valve lash caps and you see what they are.

Oil pressure can be improved by removing the inline filter, checking the oil pump for smooth operation, checking the intake line for kinks or any out of round condition. We had one bike that had slag in the oil tank outlet(oil pump inlet hose side) that kept oil from fully running to pump causing erratic readings. I really implore anyone read this to make a guage to check you oil pressure. The dummy light doesn't come on until the pressure is really low and even then it might not come on as we have found out.
Do you know whether the factory non return valve in oil pump is a cause for this?
 
Mate, have you got a "this is one we've done" or a link to a "buy it now"?

I've looked at doing this before, but wasn't confident enough in my knowledge of the oil system to trust that I wasn't going to do something that made things worse......
A gauge could be easily adapted just by plumbing into the motor where the oil pressure switch is and mounting a gauge.

 
A gauge could be easily adapted just by plumbing into the motor where the oil pressure switch is and mounting a gauge.

Thanks @Voodooo I have no idea how I didn't find that thread when I searched.......
 
What mileage please?
Hello Clive, the mileage was 8500 I am now on 10200 so I will check the rockers in the next couple of weeks.
Thanks to everybody who contributes to this forum and I hope Norton read these problems and help us overcome them, good for their business to listen.
Had a phone call off Norton the other day to see if I wanted to place an order for a new Norton so they are starting to generate their business, look forward to motor bike show next month.
 
Hey Clive, agreed - essential forum! Where else do you get so much learned experience from a group of really knowledgeable enthusiasts, with a smattering of Norton mechanics thrown in for good measure! We just need to resolve teleportation, so you could just hit the ‘engage’ button to receive a visit!

For those less tech savvy amongst us, how obvious was the change in mechanical noise that you noticed at the outset of this mechanical adventure? I know the sound of my engine - I understand it to be quite quiet for a 961; so I’m told! Would mr technically challenged have noticed this change, or do you need to have semi-synthetic oil running through your veins and an intimate knowledge of the valve train?

Asking for a friend :rolleyes:! Thanks!
 
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For those less tech savvy amongst us, how obvious was the change in mechanical noise that you noticed at the outset of this mechanical adventure?
I heard a rattle which built around 4000rpm - Once we are aware of a weakness we have 2 options - check on a regular basis or install a permanent fix. Most important is knowing what to look for. I have worked on cars for 50 years but now getting a bit lazy so it’s easy to ignore an issue. Can’t do that with these bikes SOMETHING WILL FAIL 100% GUARANTEED. And it could hurt a lot more than the wallet.

Fortunately it’s actually an easy bike to work on. If you’r not confident lure a friend with beers to help and show you.

Probably could put together a check list with guides to take to your local bike shop to work through as a preventative maintenance schedule. Sprocket tab washer, rockers, Cush drive, relays, battery cradle, oil pressure, compression........

Oh yes and anyone got a handy Covid fix? Got the damn thing again not as much fun as the last time...
 
Thanks Clive - good to know that it was a particular noise, at particular revs; one to watch out for. My technically challenged friend will appreciate that :rolleyes:!

Unfortunately, I rarely relax on my rides - I have to tell myself to do so, or else what’s the point! I’m listening for any change in engine note and for it to decide to stall at the inevitable red light. I tell myself that this makes no sense! Apart from a couple of gear change rod failures, a head temp sensor failure and a battery terminal problem ’my precious’ has been faultless!

I’m an avid follower of this forum and soak up technical advice like my liver absorbs beer on Friday night, but I decided long ago to abandon most preventive maintenance cos - ‘if it ain’t broke’ etc etc! Then you appear out of nowhere with your ‘the engines gonna explode, 100% guaranteed’ thread to ruin my blissful ignorance! 😫

Thanks for warning me though. I’ll tell my friend!
 
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Mate, have you got a "this is one we've done" or a link to a "buy it now"?

I've looked at doing this before, but wasn't confident enough in my knowledge of the oil system to trust that I wasn't going to do something that made things worse......
sent you a PM
 
Hey Clive, agreed - essential forum! Where else do you get so much learned experience from a group of really knowledgeable enthusiasts, with a smattering of Norton mechanics thrown in for good measure! We just need to resolve teleportation, so you could just hit the ‘engage’ button to receive a visit!

For those less tech savvy amongst us, how obvious was the change in mechanical noise that you noticed at the outset of this mechanical adventure? I know the sound of my engine - I understand it to be quite quiet for a 961; so I’m told! Would mr technically challenged have noticed this change, or do you need to have semi-synthetic oil running through your veins and an intimate knowledge of the valve train?

Asking for a friend :rolleyes:! Thanks!
If you listen to some of the videos that Norton is putting out, the "sound" is scary loud.
 
No, we know that the lack of flow to the oil pump was the main issue and that the relief valve was sticking. I would get rid of the valve in the oil pump and install the one from Thiel.
Sorry to beat this topic to death but I'm not clear on what you are referring to as the relief valve.
Where is this valve located?
 
Since we are talking about oil pressure and the rockers, if you have seen the oil routing, I beg you to look at it and see how critical this is. If the rockers aren't fed properly, then you can have this happen rapidly.
 
Since we are talking about oil pressure and the rockers, if you have seen the oil routing, I beg you to look at it and see how critical this is. If the rockers aren't fed properly, then you can have this happen rapidly.
I'm sure this topic has been discussed ad infinitonauseum, but since we
are talking about oiling of the innerds, what is the proper oil level to both avoid oil in the airbox and not deprive the engine of proper lubrication. I added an extension to my dipstick and run the oil level at just the level that would have fallen from the bottom of the stock dipstick. My oil collector bottle from the airbox fills slowly this way. I have the modifications that were supposed to have solved this problem but if I overfill , it still dumps oil. How crucial is oil level in engine lubrication? Is it a small or large acceptable oil volume range? I've reviewed the oil flow path information. I guess proper viscosity is also very important.
 
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