RGM Cam followers - Lifters

Its a world of compromises. Webcam does good work but they require a used cam core to start with - you have to check the journals for wear before sending it to them and they polish the journals. Megacycle has new billet cams with hardwelded lobes but the journals are not hardened (they seem to hold up). Other billet cams use a variety of hardening processes - some better than others.

Webcams journals are normally polished to somewhere between .001 and .003 undersized.
Norton cam bushings are undersized when they are installed so they can be reamed for the proper fit.
I always figured if you were concerned about the bushing clearance when installing a Norton cam then you should have an adjustable reamer anyway.
I just replaced my 30 year old reamer with a new carbide tipped reamer.
I paid a whole $36.37 for it surplus NOS on e-bay.

comnoz said:

Norton cam bushings are undersized when they are installed so they can be reamed for the proper fit.
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I have to admit to reaming new camshaft bushes to 0.8750" and wondering if that was to tight although rotation was super smooth.
You have me wondering again............
The same reamer with some new guides did the swing arm bushes also.

Time Warp said:

I have to admit to reaming new camshaft bushes to 0.8750" and wondering if that was to tight although rotation was super smooth.
You have me wondering again............
The same reamer with some new guides did the swing arm bushes also.

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As long as they don't bind When the cases are together they are probably good to go.
That's an interesting jig you have there.

comnoz said:

Hopefully not the same followers I tested.

I now have carbide faced followers in limited numbers available.
They are only suitable for use on Webcam Stelite camshafts -they are not compatible with case hardened cams.
They have been tested for ~ 300 hours in my spintron with virtually no wear.
They use a hardened chromoly body and weight 20 to 25 grams less than stock.
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Nice looking stuff, Jim. There's clearly a lot of development work behind those.

Ken

I tried several different alloys looking for the best and hoping to find something that was a little more universal. If there is an alloy to that will last with all the cams -then I don't know what it would be.
The spintron ran for weeks. I rolled it outside during the day and back into the shop at night.
I had a security camera on it so I could keep an eye on it in the evening.
It spent a lot of time varying back and forth between two speeds. Too fast for the tack to follow. 6000 to 8000rpm test.
No cooling fan so the oil temp was usually over 300 degrees.

Sometimes really hot

comnoz said:

As long as they don't bind When the cases are together they are probably good to go.
That's an interesting jig you have there.

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With the cases together it was so smooth I thought it to good to be true.
The reamer guiding device needed some set up but made it a 10 minute job in the end.

The reamer shaft guides were the old inner bearing races from my 1949 Sunbeam's gearbox, so British all the way.

Hi T W,
Is line reaming not needed or not possible?

Ed

Time Warp said:

I have to admit to reaming new camshaft bushes to 0.8750" and wondering if that was to tight although rotation was super smooth.
You have me wondering again............
The same reamer with some new guides did the swing arm bushes also.

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Fast Eddie said:

Yes, I hope this leads to someone taking it up too, especially if those followers are in plentiful supply!

But I still see challenges.

If you look at the picture below you’ll see that it’s not gonna be easy to fit a follower with a longer foot.

You can also see how the A65 followers rely on the fore and aft support to keep them aligned. It’s these fore and aft support parts that have to be set high enough to clear the lobe. And when this is done, there is only a small amount of follower being supported when it’s on the lobe base circle. As lift commences, this can cause the follower to dig in to the flower block. Hence the importance of setting them up to give min clearance and max support.

The tapered design of the follower you showed would make this an even bigger challenge, the follower edges just aren’t gonna be deep enough. A complete redesign would be required I feel.

In the second picture below you can see how this was such an issue with big cams that Herb Becker extended the follower feet depth in order to countermeasure the issue of lack of support.




View attachment 7720 View attachment 7721

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The BSA B50 lifters have a longer foot so they can be buried deeper in the lifter guide (or lifter block) and have enough overlap for high lift cams. The Norton lifter tunnel isn't large enough to accommodate the longer foot of the B50 lifter.



The taller lifter foot for the BSA A65 lifter as shown below was modified to make it safer for the most extreme of all Norton cams - the Sifton 480 cam which is too wild for most racers. You can still get stock BSA lifters to work with the 480 cam (but just barely). The BSA A65 lifters are fine on Sifton 460 (D+ cam) and all the other cams because they have less lift than the huge 480.



The BSA A65 lifters weigh less than all the other Norton lifter options and they come with the benefit of a 1.125" radius. (reground to .875" radius for Sifton 460 and 480).

APRRSV said:

Hi T W,
Is line reaming not needed or not possible?

Ed

Click to expand...

Ed
I believe the bushes are line reamed with this device.

There is some set up time checks as where you point it, it will ream.
The upper portion unbolts from the base to take a second mandrel to secure the reamer shaft (again bolted to the base) so the D/S bush can be reached.
Line reamed.

When I first googled reaming Norton cam bushes it went nowhere so did it my way for better or worse.
#
RGM followers are AN followers so the latest AN followers will be the next new RGM followers.
Hopefully there will be a OEM type follower for the 10's -thousands of the 'just want to ride their Commando's folk.
At $900 a set and unknown life expectancy the latest AN (RGM) version is just that, an unknown and most likely out of reach for many.

It costs a lot of money to make the parts (in general) that is the catch 22.
The cost of re face able OEM followers will rise based on the RRP of new replacements.

Time Warp said:

Ed
...................The cost of re face able OEM followers will rise based on the RRP of new replacements.

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The cost of re-faceable used OEM followers will also rise based on availability of said used items!

Yet to see if the items coming to market will be as re-faceable as older items. Do they need to be?

Running a cam matched to the follower materials seems like a way of getting a good in service life, assuming other maladies don't destroy parts! (racer mentality, it will happen!)

Based on anticipated mileage and use, this might make changing the whole cam/follower set the best investment?

SteveA said:

Yet to see if the items coming to market will be as re-face able as older items. Do they need to be?

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If the two materials (follower face and cam lobe) are compatible and in some form of harmony (don't wear within acceptable mileage) they would not need to be refaced.
Is that even a known at this stage ? (and ask this as someone who has spent quite a bit of money at AN on two Commandos so not a case of biting the hand that feeds you )

(There are probably 1000's of old followers out there with a groove across the follower face still doing fine)

A camshaft/follower package would be ideal but at what cost, down this way with the exchange rate that could be the best part of $2000.

My point (complaining/whining ? ) is, a new follower for the masses is great but where is the testing.
No one is that stupid to just drop a part on the market like that without testing to at least prove to themselves the part is fit for long term life in a real world environment. (In a road going Commando for extended mileage as they did at the factory 50 years ago..R.I.P Frank Damp)

Lets not forget the fiasco before (here) and shortly after followers being removed for purchase from AN.
For that reason alone they better be good and proven to be so 100%.

Time Warp said:

.....
A camshaft/follower package would be ideal but at what cost, down this way with the exchange rate that could be the best part of $2000.

My point (complaining/whining ? ) is, a new follower for the masses is great but where is the testing.
No one is that stupid to just drop a part on the market like that without testing to at least prove to themselves the part is fit for long term life in a real world environment. ......

Click to expand...

There are clearly limits to the investment in testing that a concern like AN or even smaller can make. However, what I see is an honest intent, for example sending some to Jim for testing.

This revealed problems which can be addressed.

Should we expect what a fully fledged motorcycle manufacturer was able to do in the 60s/70s? Realistically, no.

Bear in mind that Norton had their own issues due to lack of R&D and testing, and lo and behold, that has been a huge issue since 2008!

I was in contact with SRM whilst they were testing A65 style followers, again an honest attempt to test before bringing to market, but as far as I see it the BSA world has a few less permutations of camshaft source to deal with!

I have opted to remain with a Norton style follower so I greatly welcome Jim's initiative. It will suit me.

Most of my options end up around 1000 financial units,. This becomes 2000 to you because of the currency valuation will only buy around 1000 of most of the units used in the northern hemishpere. manufacturers and suppliers have no control over that.

Of course, by this time next year the financial units I am paid in may only be worth the same as the ones you use!

Currently working to have a batch of BSA lifters made new. Radiused, light weight and long lasting - BSA lifters are the best choice of all the classic Brit bike options. Thats why Norton used them on their factory sponsored short stroke dirt track race bikes.