Cam and follower tests.

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I had a 70 model where the left side lobe was pitted toast on a teardown. All 3 to the right were perfect. No explanation I could see , regular oil changes.
 
Hi, Since we have some very talented people here. Has any one considered developing a Roller Cam and Cam shaft for our Norton engines ?
 
Hi, Since we have some very talented people here. Has any one considered developing a Roller Cam and Cam shaft for our Norton engines ?
No we need a cam shaft hardness and a follower hardness to be compatible with each other, so they don't destroy each other.
We need to get it right.
T
 
"Yes, I put needle bearings right next to the lobes and a ball bearing next to the sprocket to support the RH end and control the end play."
Jim, Your bike is highly modified (and I admire that) but what about us low life's who just rebuild to factory spec.
What we need to see is a stock high mileage cam and lifter set up with Rockwell C testing on both Followers and Cam that have stood the test without wear. What can we derive from that correlation. I am really confused why one lobe takes a dump.
Cheers,
T

In the past I have hardness tested 100's of cams and never really seen any correlation between the cams hardness and the failures. I have yet to see a soft lobe on a case hardened OEM cam -but I have seen a lot of them wiped out.

Some of the older weld-up cams were quite soft. Norris cams were generally in the 40"s and they seemed to hold up pretty well for a cam with harsh acceleration rates.

But now since I have started testing both the cam and the followers I am seeing a definite pattern.

I have a pretty good collection of old followers with damage such as scored bodies or broken pushrod cups. I have gone through and tested them and found the majority of them to be between RHc 57 and 60. And then I see about 1 in every ten that is closer to RHc40 and most of the softer followers show scoring indicating they had been run on a failed lobe.

I will continue to test every cam and follower set I can get my hands on and see if the pattern continues.

I seldom have people send me all good cam and lifter sets, but I do have access to a few intact sets that I will be testing soon.
 
Since when have oil companies been reputable? You must have different standards to me.

I didn’t say all oil companies are reputable Ken, I said why not use oil from a reputable company (two very different points).

Like (but not limited to) Redline. I use their oils almost exclusively in my bikes.

If you’ve got any evidence as to them being unreputable, let’s hear it...

IMHO, I find that although their oil is expensive, it tends to work out less expensive than premature engine rebuilds.
 
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The oil you use probably costs a good deal more than other oils plus the cost of the little bottle of zinc poop. For most of us oldsters the cost
of oil today is unbelievable.
However, the cost of our bikes is equally beyond what we would have ever paid so, as per your policy, false economy using less than premium oil.
Maybe it doesnt matter, in which case you can simply say better safe than sorry.

Cost of oil vs cost of failure. Plus peace of mind. That’s why I’m happy with my oil choice.

We spend a lot of money on these old bikes. Saving money on engine oil cannot possibly be efficient in the longer term IMHO.
 
I have been using Penrite 20w/60 with high zinc ,changed around every 3000 miles.(for around the last 18,000 miles)
 
Instead of adding some kind of additive to the oil, why not just buy good oil with a high ZDDP content? That way you know the entire oil and additive ‘recipe’ is going to be good, and work together.

I can’t follow the logic that says we blokes in our sheds can mix a better oil than the top end reputable oil companies !

Absolutely, tribology is a very complex subject, and the idea that you can magically improve your oil by dumping in a can of goop has more to do with superstition than science.
After talking to several oil engineers, it seems that ZDDP is not the only solution, and causes problems with some of the other additives in use, so there is a good chance that the goop in the can is not actually improving the performance of the total mixture. Remember when the hot thing to do was to use STP in the engine?
 
Cost of oil vs cost of failure. Plus peace of mind. That’s why I’m happy with my oil choice.

We spend a lot of money on these old bikes. Saving money on engine oil cannot possibly be efficient in the longer term IMHO.

But you've seen that Ashley, AN's esteemed "engineer", uses the cheapest oil he can get and changes it at 1000 miles with absolute success. That should be good enough for all of you. Don't turn this into an oil thread. It's about the supply of unsuitable followers made from non-compatible material.

By the way, after 21 pages of my thread with denial, accusations, bluster, diverting blame and, dare I say it, bullshit, where are AN on this debate, now that it has been shown, scientifically, that the followers are at fault, and not made "to original specification", as claimed in all their advertising?
 
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CanuckNortonNut
My thoughts too. No reason why, in the 21st century, we shouldn,t be able to just buy, fit and forget cams and followers, like my old high compression 750 motor in the 70,s.
Eventually fitted a different engine and sold all the bits separately, O.E. Combat cam and followers were perfect after 10k+ miles, I recall the buyer measuring them with a micrometer.
Hopefully Comnoz research will throw up an answer, in the meantime will keep a nervous eye on my Web312 and AN followers from 2017.
 
in the perfect world a solution would be simple but we have to accept the fact the cam and follower design was flawed from the get go
Norton had many issues with incompatible materials and this is still rearing its ugly head today numerous suppliers have tried different options steel billet / chilled iron / hard facing by welding
various different combinations of oil and still no definative solution to why they continue to fail

i have some sympathy for AN as a supplier they are limited to provide materials which are to the original flawed design (made from non compatible materials ) as they were OE by Norton otherwise they will not fit and work without major modification to the cases / cylinders . AN material specs may have changed but the actual design must remain the same ( flawed )

many automotive manufacturers in the 1980s and 90s also had premature camshaft & follower failiures only through development have these been all but eliminated today

the last Commando rolled of the production line in the mid 70`s and as owners we have to accept that vehicles produced over 40 years ago will have issues that cannot be be solved without a complete re design it is part and parcel of owning an old machine , we can spend thousands on restoration and upgraded parts to make our bikes more user freindly
but they are still a 50 year old design and will not perform and handle like a new 2018 machine which has cost millions to develop to that standard
 
...now that it has been shown, scientifically, that the followers are at fault, and not made "to original specification", as claimed in all their advertising?
Has that been shown, or is it suggesting that the original specification that could be improved? A friend recently pulled a late '60's 650SS down to find the reason for its asthmatic performance was a very worn cam follower. Plus ca change etc.
 
in the perfect world a solution would be simple but we have to accept the fact the cam and follower design was flawed from the get go
Norton had many issues with incompatible materials and this is still rearing its ugly head today numerous suppliers have tried different options steel billet / chilled iron / hard facing by welding
various different combinations of oil and still no definative solution to why they continue to fail

i have some sympathy for AN as a supplier they are limited to provide materials which are to the original flawed design (made from non compatible materials ) as they were OE by Norton otherwise they will not fit and work without major modification to the cases / cylinders . AN material specs may have changed but the actual design must remain the same ( flawed )

many automotive manufacturers in the 1980s and 90s also had premature camshaft & follower failiures only through development have these been all but eliminated today

the last Commando rolled of the production line in the mid 70`s and as owners we have to accept that vehicles produced over 40 years ago will have issues that cannot be be solved without a complete re design it is part and parcel of owning an old machine , we can spend thousands on restoration and upgraded parts to make our bikes more user freindly
but they are still a 50 year old design and will not perform and handle like a new 2018 machine which has cost millions to develop to that standard

Absolute fluff ! How do you explain the thousands of Commandos through the years which have shown excellent reliability, including the one I owned in the 70's (with admittedly poor maintenance) which show excellent reliability? This is a compatibility issue, due to followers not made to a spec which is compatible. IT IS A QUALITY CONTROL ISSUE!!!! How come a (rather talented) lone operator in the wilds of Colorado can diagnose the problem and begin working on a solution when a company, with claimed competent testing facilities, with lots of letters after their name, cannot?
 
Has that been shown, or is it suggesting that the original specification that could be improved? A friend recently pulled a late '60's 650SS down to find the reason for its asthmatic performance was a very worn cam follower. Plus ca change etc.

See Jim's explanation. What do you think?
 
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