Crank movement

would it make a difference if the loctite was only applied to the bottom(weightbearing) quadrant of the bearing housing to allow for the different thermal expansion of the steel and alloy to repeatedly happen?
No, when I tried it the failure was all the way round, it must start on one side but still goes to the far side from the first failure.
 
.........

Alternatively, if you believe that the crank and cases didn't change from the days when the timing side had a ball bearing (I have no idea), then the shims should only go on the drive side.
That was creative, I didn't say the cases were not changed, I pointed out that prior to the use of rollers in both sides, the ball race fitted on the timing side did the sideways location and shims were not required!

Either side.

At least one UK vendor of Norton parts was promoting the use of ball races on the timing side way after Norton were no longer trading!

And just in case you are wondering, personally, I have never used a ball race on a Norton crank.

In the interest of a longer life, mine that is, I would never contemplate putting a whole bottom end in the freezer....nor do I believe you could measure any performance difference based on less than 20 thou left or right at the rod to pin interface!
 
That was creative, I didn't say the cases were not changed, I pointed out that prior to the use of rollers in both sides, the ball race fitted on the timing side did the sideways location and shims were not required!

Either side.

At least one UK vendor of Norton parts was promoting the use of ball races on the timing side way after Norton were no longer trading!

And just in case you are wondering, personally, I have never used a ball race on a Norton crank.

In the interest of a longer life, mine that is, I would never contemplate putting a whole bottom end in the freezer....nor do I believe you could measure any performance difference based on less than 20 thou left or right at the rod to pin interface!
I did not say or imply that you said anything! I did not reply to your message.

If you actually read what I wrote in my first two sentences it should be clear that you response is inappropriate and I was offering my opinion one the subject in general.

I am fully aware of what you said and what you meant about ball bearings. In fact, that's the way Triumph did it -- crank locked to the timing side ball bearing for most of the final years.

I even left this alone:

"Also note, prior to using rollers in both sides, the timing side race was a ball race. No lateral float to speak of so no shims.

Meaning that the timing side is the side that does the side to side location, so it seems to me logical to shim that side! It has the pump worm tightened onto it to keep stuff located.

Or does someone know different?"

The 2nd sentence is backwards - if one followed you logic, the only place for the shims would be the drive side.
 
I did not say or imply that you said anything! I did not reply to your message.

If you actually read what I wrote in my first two sentences it should be clear that you response is inappropriate and I was offering my opinion one the subject in general.

I am fully aware of what you said and what you meant about ball bearings. In fact, that's the way Triumph did it -- crank locked to the timing side ball bearing for most of the final years.

I even left this alone:

"Also note, prior to using rollers in both sides, the timing side race was a ball race. No lateral float to speak of so no shims.

Meaning that the timing side is the side that does the side to side location, so it seems to me logical to shim that side! It has the pump worm tightened onto it to keep stuff located.

Or does someone know different?"

The 2nd sentence is backwards - if one followed you logic, the only place for the shims would be the drive side.
The English language is a wonderful thing. We maybe need to recognise we use two different dictionaries and grammar sets, and phraseology.

I doubt we understand each other much.

Trawl the posts here, if you have the time or care too, at some point Comnoz was very clear in his opinion: don't put crank mounted shims on the drive side, ever. I understood because he has had occurrences of them 'squeezing out'.

Crank mounted shims on the drive side are only secured by the fit of the inner race on the crank and subject to the transmission loads. In most cases the inner race to crank fit is very tight, and I doubt they would move, but the risk exists, surely best to avoid it?

Crank mounted shims on the timing side are secured by the fit of the inner race on the crank and the oil pump worm, which holds the timing pinion, backplate and sealing washer to the inner race. I really doubt they move, but I guess it is possible, which, alongside ease of installation, is surely a contributory reason for people going to case/outer race mounted shims?

I reckon you can put case mounted shims either side. Indeed, if you thought it important to centralise the crank, that would be a way to do it. Dividing the shim load is also a way of making sure the race is lifted in the case the minimum amount, which others here have expressed concern over.

To date, I haven't used case mounted shims. I am considering that for the future.
 
To date, I haven't used case mounted shims. I am considering that for the future.
Steve, have you seen my post#66 to answer your questions?

In my overhaul project, case mounted shims will be for the future, like you. After 609 Loctite and put some weight on the bearings, crankshaft showed thigh spin. I had to pull out the drive inner race (0.0005''interference fit-ouch!) to remove a 0.010'' shim. Now the thing spins easily with a 0.008'' end play. Despite your statement in your post #65 Steve, this thread is not dead...LOL
 
Steve, have you seen my post#66 to answer your questions?

In my overhaul project, case mounted shims will be for the future, like you. After 609 Loctite and put some weight on the bearings, crankshaft showed thigh spin. I had to pull out the drive inner race (0.0005''interference fit-ouch!) to remove a 0.010'' shim. Now the thing spins easily with a 0.008'' end play. Despite your statement in your post #65 Steve, this thread is not dead...LOL
Yes, I had read it, as a point of interest when I built my first race motor I used a set of John Hudson's notes, acquired the hard way, well at least for my wife. She kindly typed a copy from a set lent to me by my local Norton dealer in 1975. Not much photocopying about then! (I still have the notes).

The motor was based on MkIII cases and crank and, like Mr Hudson, I followed his advice and didn't worry much about end float, checked there was some and did no shimming at all!

I suspect even today that was the quickest Norton I ever rode.

But we move on.
 
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The English language is a wonderful thing. We maybe need to recognise we use two different dictionaries and grammar sets, and phraseology.

I doubt we understand each other much.

Trawl the posts here, if you have the time or care too, at some point Comnoz was very clear in his opinion: don't put crank mounted shims on the drive side, ever. I understood because he has had occurrences of them 'squeezing out'.

Crank mounted shims on the drive side are only secured by the fit of the inner race on the crank and subject to the transmission loads. In most cases the inner race to crank fit is very tight, and I doubt they would move, but the risk exists, surely best to avoid it?

Crank mounted shims on the timing side are secured by the fit of the inner race on the crank and the oil pump worm, which holds the timing pinion, backplate and sealing washer to the inner race. I really doubt they move, but I guess it is possible, which, alongside ease of installation, is surely a contributory reason for people going to case/outer race mounted shims?

I reckon you can put case mounted shims either side. Indeed, if you thought it important to centralise the crank, that would be a way to do it. Dividing the shim load is also a way of making sure the race is lifted in the case the minimum amount, which others here have expressed concern over.

To date, I haven't used case mounted shims. I am considering that for the future.
Actually I was wondering if it was a language issue. I'm sure there's some of that; but, I can detect no issues with your English writing so I have to assume you understand written English. You make less typos than me.

Still, I expressed no opinion on crank or case mounted shims and I started by saying I would not shim.

BTW, reading your posts, I figured you were an ex-pat American as your English seems more like US English than UK English and often (in my experience) the English instruction in European countries is done by British teachers.

I value the opinion of all and Comnoz more than some, but they are all opinions, including mine. There are some proven things found here, but they are few and far between. For instance, I have "proven" time and again that Amal Concentric carbs do not need and should not have chokes and that the throttle must not be opened when starting - others have "proven" the opposite.

Also, more than once someone has quoted Comnoz and when you find his actual words, they have paraphrased, not quoted him (not saying you did).

To be very clear:

1) I would not shim the engine in question.
2) If I were going to shim any Commando engine, I would not just stick in shims - I would follow the procedure I outlined to figure out the best shim arrangement. Also, based on the statements people have made about crank/crankcase shims in various threads, I would use crankcase shims (first time ever that I expressed a thought on that).
 
Actually I was wondering if it was a language issue. I'm sure there's some of that; but, I can detect no issues with your English writing so I have to assume you understand written English. You make less typos than me.

I'm English, but I have lived in France for 5 years since retiring. Only yesterday I received my permanent residence card. I lived/worked in Italy for the last 8 years of my working life with multinational suppliers and customers.

Prior to that, I worked for a French company for 7 years, during which I worked multinational research and study programmes across Europe and with NATO.

I speak a little French, apparently with an Italian accent! My biggest problem is understanding more of it because I am very deaf these days. I have forgotten most of my Italian, but it should come flooding back with a restaurant menu in my hands.

At one time I lived/worked in the US. I have also spent a lot of time working with Canadians, and several European nationalities. All of my career was in aerospace, mainly flight simulation and pilot training systems, with some technician and engineer training systems thrown in.

My working life included a lot of document writing for multinational/multidiscipline audiences, leading technical workgroups, and chairing mainly technical meetings. When I retired I was also the chairman of the specialist group addressing flight simulation and pilot training at the Royal Aeronautical Society. I worked with that group for over 15 years delivering a lot of multinational specialist conferences.

Whilst I grew up using British English and I still favour it, I have had to use mainly US English over a period of years.

Might have been nice on a CV a few years ago, but today none of this matters at all to anyone.

But it does make me who I am, which today is just a retired person playing with one '50s motorcycle, three '70s motorcycles and a '50s car (saloon in my language, sedan in yours).

I try to write as appropriate for a motorcycle forum readership, I sometimes miss the mark! (Witness this post).

I make fewer typos because I go back and edit my stuff! It's habitual. I also use a real time spelling and grammar checker. ;)


 
I speak a little French, apparently with an Italian accent! My biggest problem is understanding more of it because I am very deaf these days. I have forgotten most of my Italian, but it should come flooding back with a restaurant menu in my hands.
This one made me smile. I've worked in several countries as well. The longest was Germany. I lived on the economy but worked with US, NATO, and former Soviet forces so my German was never well honed. I understood fairly well, could usually understand things like news papers, and I could even make myself understood (just barely). One time on a Volksmarch (club walk) a club from France participated. I spoke no French, they spoke almost no English but we could communicate in broken German. Fortunately, Germans put up with the slaughtering of their language and usually tried to help. When I went to France I simply spoke English - less dirty looks that way.
 
Well, we're certainly an international bunch here aren't we, kinda cool when ya think about it. I mean the technology that allows us all to connect like this is amazing (at least to me anyways---...just thought I'd tack that "s" on the end there 'cause it sounds more like the way I talk/speak)......wow, even more off track now, sorry..,,,,,, I think you'd be okay without spliting the cases for that 18 thousandths end float that you have there Woody850.
 
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Iā€™ve started a tear down of my 13k mile Mk3. I just pulled off the outer/inner primary case and components and checked the crank end play by simply trying to pull and push on the end of the crank and I canā€™t detect any, as in zero, side-to-side movement. From reading this thread and an older one on end play, this doesnā€™t seem correct. Although the end play should be minimal, I'd think I would be able to detect some movement. Does this need to be checked while the engine is in a specific position?

As far as I know, the crank case has never been apart although the PO claimed it did get a top end job and piston replacement about a thousand miles ago. I wouldn't think that work would affect the crank end play.
 
Iā€™ve started a tear down of my 13k mile Mk3. I just pulled off the outer/inner primary case and components and checked the crank end play by simply trying to pull and push on the end of the crank and I canā€™t detect any, as in zero, side-to-side movement. From reading this thread and an older one on end play, this doesnā€™t seem correct. Although the end play should be minimal, I'd think I would be able to detect some movement. Does this need to be checked while the engine is in a specific position?

As far as I know, the crank case has never been apart although the PO claimed it did get a top end job and piston replacement about a thousand miles ago. I wouldn't think that work would affect the crank end play.
It be OK once you pull the timing cover off and remove everything bolted, timing chain/gears, oil pump etc then I am sure you will get some crank side movement, so why the pull down if the top end was rebuilt 1k miles ago, if the crank is spinning without any loud noises and if it's running OK I would leave it alone and just ride it doing the usual maintenance, 13k miles is not many miles really.
Changing the oil and checking the filter or drain plug for signs of metal from wear and tear will tell you a lot.
I did a rebuild for a friend who wanted to replace everything down the bottom end, but after pulling it down the main bearings where like new still the conrod bearing had a little bit of wear but still in good condition, cam was real good so asked him why, he just wanted to be sure as the only problem it had was one exhaust tread was stripped at the bottom of the thread from lose header pipe but was repairable, other than that the motor was in great shape.
He never got to ride it he past away before he put the rest of the bike back together, such a same as the bike wasn't in bad condition when he brought it with only a few minor things needed attention on the frame and tank respray.

Ashley
 
My situation is similar to a lot of people. You buy a bike with no documented history. You hope for the best, but question everything. I actually don't want to rebuild the motor given claims by PO, rather refresh the brakes, clutch, wheel, steering head bearings, cables, tires, etc. ... essentially everything that ensures it's dependable and safe to ride at speed... and look nice. But you find things like zero end play on the crank and start to question things. That said, I've read the Mk3 camshaft and the gearbox layshaft bearings are suspect so those may need to be addressed.

Back to the crank, you're saying I need to dissemble the timing chest to check end play?
 
My situation is similar to a lot of people. You buy a bike with no documented history. You hope for the best, but question everything. I actually don't want to rebuild the motor given claims by PO, rather refresh the brakes, clutch, wheel, steering head bearings, cables, tires, etc. ... essentially everything that ensures it's dependable and safe to ride at speed... and look nice. But you find things like zero end play on the crank and start to question things. That said, I've read the Mk3 camshaft and the gearbox layshaft bearings are suspect so those may need to be addressed.

Back to the crank, you're saying I need to dissemble the timing chest to check end play?
Yes , you need to inspect for the Layshaft Bearing and Cam health. I've never worried about end play , 5 Nortons later. There are always other thingys to worry about . Proceed.
 
I think you are over thinking things if the bike is running good and the motor pulling great I leave it alone, fix up the things that are needed, if the cam is worn you will know when doing maintenance valve adjustments etc, if your GB is changing good and right leave it alone, drain the oil and check it out.
Like I say if the motor is running good then I say the end play is all good, remember your bike is coming up to 50 years old and it only has little mileage on it and if the top end has been done 1K miles ago they would have been able to see the cam condition when the barrels were lifted off.
Pulling a motor down just because you don't trust the person you brought it off, if the maintenance has been kept up and oil changes done I leave it alone as these motors are very reliable, be a different story if the bottom end was making a lot of noise and being a push rod motor they do clatter when running.
 
Workshop manual 06.5146 states .005-.015
Workshop manual 00.4224 states .010-.024
Old Britts states best is: .005-.010
Factory didn't care best I can tell (cranks not shimmed)

So, yes - there are "published specs". However, there is no standard and as far as I can tell, no consensus. I even read once about a guy building race engines who wanted as close to zero as possible as long as there was no binding since the cases expand when heated. He also wanted the rods centered in the pistons and shimmed both sides to achieve both goals. I would be surprised if he could prove any measurable gain from his efforts.

The OP said: about 1/8 - not: it measures 1/8" Assuming he means 1/8" and if that it is accurate, it is too much. However, that's a bunch of assumptions and honestly .125" is very unlikely. Other threads on this subject have devolved into arguments - surprised that the argument this time is me wanting to stay out of the argument :)
The last time i did my crank it ended up at .008 ...happy camper šŸ˜Ž
 
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I think you are over thinking things if the bike is running good and the motor pulling great I leave it alone, fix up the things that are needed, if the cam is worn you will know when doing maintenance valve adjustments etc, if your GB is changing good and right leave it alone, drain the oil and check it out.
Like I say if the motor is running good then I say the end play is all good, remember your bike is coming up to 50 years old and it only has little mileage on it and if the top end has been done 1K miles ago they would have been able to see the cam condition when the barrels were lifted off.
Pulling a motor down just because you don't trust the person you brought it off, if the maintenance has been kept up and oil changes done I leave it alone as these motors are very reliable, be a different story if the bottom end was making a lot of noise and being a push rod motor they do clatter when running.
I agree with you Ash about the motor
But I'd have to pull the gearbox to check if the Portuguese layshaft bearing had been banished
 
.005" - 0.15" is the end float for the original drive-side roller and timing-side ball bearing.

.010" - .024" is for two roller bearings, specified in Norton Service Release No.68, October '71 (twin pre-Superblend rollers introduced from serial 200000), also Service Release N2/10, January '73, the introduction of the "Extra high capacity main bearings" (FAG NJ306E).
Unfortunately, this information wasn't included in the 06.5146 manual.
 
.005" - 0.15" is the end float for the original drive-side roller and timing-side ball bearing.

.010" - .024" is for two roller bearings, specified in Norton Service Release No.68, October '71 (twin pre-Superblend rollers introduced from serial 200000), also Service Release N2/10, January '73, the introduction of the "Extra high capacity main bearings" (FAG NJ306E).
Unfortunately, this information wasn't included in the 06.5146 manual.
My mk2a had 24 thou end float from the factory with no issues
 
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