The Commando that came in from the Cold.

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Starting at the start:

L.A.B. said:
Yes, the NJ203E is the layshaft 'Superblend' roller upgrade, part 06-7710.

The 6203 ball bearing was both wheel bearing and the original layshaft bearing and why they had the same part number 04-0100.
If you were sent NJ203E bearings as wheel bearings under part 04-0100 that was a mistake.

Thanks for all the advice L.A.B., this confirms much of what I was thinking, and seems like it might save me a fair bit of both effort and money. Some deep creep might address the stuck stud, which had resisted initial effort to be forced through. (with a nut over the thread my dear friends, let it not said I destroyed the threads in my rust induced, hammer swinging rage...)
And, some type of updated verniers will probably be winging along here to replace what I have. Perhaps I will give Mr. Hemming a call on a weekday, not to disturb his weekends peace. Even the instructions in the manual on how to adjust the isos using shims was giving me a headache, so I think getting the adjustable ones is the smart choice.

Nater_Potater said:
When it comes time to put the head back on, I highly suggest deviating from the shop manual as concerns the pushrod installation. Check out last-head-bolt-giving-trouble-t26267.html#p347542, and also check pete.v.'s link from there for more details on his "Pushrod Tampons".

Nathan

p.s. Good to see you're back!

Noted, and will do when the time comes. Which, hopefully will be soon. It is very probably a bit hopeful to think I will have her running this summer, but I do aim to have a rolling chassis, and a rebuilt engine. This would put me on track for a running, roadworthy bike by summer '18, which is probably a realizable goal.

Mr. Rick said:
" If you were sent NJ203E bearings as wheel bearings under part 04-0100 that was a mistake. "
But I wd recommend keeping at least one of these, for use as the layshaft bearing (unless it has already been replaced), which is a "nortonious" :) weak spot in the transmission.

As above. Will do. I was initially going to just send 'em all back, but something niggled about that. Glad to hear I only need one of the spendy ones for the trans. I hadn't planned on doing that complete rebuild, but I won't rule it out either. Getting that thing out of the frame wasn't exactly super fun, and I would rather not have everthing else done, only to grenade the trans my first season out riding. In any event, these are VERY nice bearings, and will compliment the 'superblends' that are going into the engine nicely.

Thanks again all.
More photos to come soon. The frame has a couple off blemishes I would like to address, and I will post some photos shortly of that, and take a couple of measurements to satisfy my own curiousity before I get too far down that road. My welding skills are amateur at best, and I still haven't found a TIG welder in my price range yet, so I may have to shop a couple of things out before I am able to even start down the path of rolling chassis. Expec many more questions and the like from this threas. FWIW - I do my best to have a good search before asking too many questions here, but there is ALOT of info here, and if I end up with a couple of things repeated, or other discussions linked fromt this one, perhaps it will be of some use to others going down the same rebuild road that I am.

Cheers,
Jon
 
Okay,

So as my intention is to attemp to keep my posts within my own initial string, I have a question about the bearing that has already been discussed here and elsewhere a little. Since I was sent a hadnful of the correct roller bearings as a wheel bearings which at ~$38.00/ea is more than a little overkill, I was planning on sending them back and getting some good, but much less expensive SKF or FAG 2S ball bearings for the wheels. However, the above advice was to keep one for, if (when?) I run into problems with the original layshaft bearing. (I gather it is a sub-par bearing for the job, and the bearing cage comes undone over time.)

Now, that said, I do not have, nor can I afford a dial guage to measure run out, and nothing else I have found here suggests another method but a bit of guess and by-golly, which I would prefer not to do. The other option seems to be the much improved deep groove ball bearing that Mick Hemmings was a proponent of. So now, with the ball bearing do I still need to worry as much about end play/runout that I need a dial guage? In short, given this bike will probably only ever get weekend use, and never see a track/serious flogging, do I need to go up to a roller bearing, or will the improved ball type do, if the install is that much less complicated. Also, since there were no apparent problems with the trans when I had it in at Highway Cycle, is wasn't at all in my plans to crack into it, aside from replacing the ancient fluid in contained.

Thoughts are always welcome.

Photos and related questions pertaining to my apparently not-quite-straight-frame are coming up next and shortly.

Cheers!
Jon
 
KzJonny said:
Now, that said, I do not have, nor can I afford a dial guage to measure run out, and nothing else I have found here suggests another method but a bit of guess and by-golly, which I would prefer not to do. The other option seems to be the much improved deep groove ball bearing that Mick Hemmings was a proponent of.



As you already have the NJ203E roller, if money is tight, it would make sense to use it, and a cheap dial gauge would probably cost you less than the "Hemmings" (FAG 6203TB) bearing!
Without a gauge, another method would perhaps be to shim to about zero end float then reduce the shim thickness by 0.005" - 0.010".

KzJonny said:
So now, with the ball bearing do I still need to worry as much about end play/runout that I need a dial guage?

From previous discussions is appears the Hemmings ball bearing is less likely to require shimming than the roller but the need to shim can't be ruled out completely.

KzJonny said:
In short, given this bike will probably only ever get weekend use, and never see a track/serious flogging, do I need to go up to a roller bearing, or will the improved ball type do, if the install is that much less complicated. Also, since there were no apparent problems with the trans when I had it in at Highway Cycle, is wasn't at all in my plans to crack into it, aside from replacing the ancient fluid in contained.

What work (if any) did Highway Cycle do to the gearbox?
As the standard ball bearing can fail at any time with little or no warning with potentially disastrous consequences for both bike and rider, basically doing nothing isn't an option in my opinion.
The bearing should at least be checked and replaced with one of the upgrades if it is found to be a standard 6203 ball bearing.
 
So now, with the ball bearing do I still need to worry as much about end play/runout that I need a dial guage?

Without having access to a dial gauge you can do it in two ways.

1. Add in shims until you can just feel some to and fro movement, this will be approx 3 thou end float as that's the minimum clearance a human can detect.

2. Add in 5 thou shims until the shaft just binds, then take out the shims, measure the stack and put back in a stack 10 thou less and double check for endfloat. This should get you close to the 5 to 10 thou needed.
 
Alright, work once again continues on the old Norton, and as always I have some associate questions to go along with it. But first, to get back to all those helping along the way.

What work (if any) did Highway Cycle do to the gearbox?
As the standard ball bearing can fail at any time with little or no warning with potentially disastrous consequences for both bike and rider, basically doing nothing isn't an option in my opinion.

Thanks for this, and for all the continued help L.A.B. In short, the Rick didn't do any work on the gearbox aside from offering that in his experience mildly driven stock configuration gearboxes should last quite a while without the bearing being changed. That said, as with so many other things, I've got the damn bike all to pieces, and have the correct (roller) bearing to hand, so I don't see why I should replace it, even tho I had hoped not to tear apart the gearbox. Having just re-watched the Mick Hemmings teardown and rebuild videos, this seems like a task I can reasonably manage, and think that even without a runout gauge, I should be able to do it just about as well as anyone else has.

2. Add in 5 thou shims until the shaft just binds, then take out the shims, measure the stack and put back in a stack 10 thou less and double check for endfloat. This should get you close to the 5 to 10 thou needed.

Kommando: while this seems pretty simple once it's been mentioned, it's a deal more clever than anything I had come up with on my own. So, failing finding a cheap and accurate(ish) runout dial, this is likely to be the method of choice. I suppose I just need to get some end shims to get started. Yet another thing to add to the growing list of purchases.


Right to the point now tho. I have one pressing concern which I have to address before almost anything else can really be worked on, and that is some minor kinks in the frame downtubes, and the passenger hoop being slightly bent downwards. No sense at all in rebuilding anything into a frame which isn't in good condition.

SO.... I know there are several Ontarians on this forum, and a handful have been in touch personally over time, so can anyone recommend anybody who is qualified to have a look at the frame and make any adjustments/repairs? Ideally this would be somewhere local to me, as shipping a frame has got to be expensive, and to my eyes, the damage is very minimal.

Photos however are worth more words than I have time for and may help get accurate feedback:

Starting with the rear loop, which on re-assessment, may be a good deal more than 'slightly' bent.

https://photos.app.goo.gl/KzGFgwZWkyluME8y1
https://photos.app.goo.gl/NUJYkwLpE8YwYZBN2

I had thought that perhaps getting the hoop supports from Old Britts might be a good idea to prevent this from being a problem again in future. Opinions?

http://www.oldbritts.com/38_200001.html

And, more importantly, the damage to the front of the cradle downtubes by the now-departed highway/crash bars which came with the bike.

https://photos.app.goo.gl/efs81zbKg4jE27yn1

https://photos.app.goo.gl/K2MjUlmI4eMlxGOt2

As it may be seen, the damage is slight (I think!) and more extensive to one side than the other. My initial thoughts were that this would need to be straightened and perhaps gusseted or sleeved? But as with so many other things, my knowledge of these frames and their eccentricities is slim, and I am relying on what would be considered a standard fix on the double cradle type frames I am more accustomed to.

Apologies as always for the long delays between continued posts in this thread, but the project moves slowly, and I hope is getting done properly as a result. To everyone who warned me, you were all quite right, and rebuilding a Norton is a costly affair! But, I reckon it's been sitting for nearly 40 years now, another couple isn't going to hurt it any.

Also, thanks in advance for any and all advice. Other work continues in the meantime, but the frame and associated repairs represent a major stumbling point just at the moment.

Cheers,
Jon
 
Regarding the fear frame loop, I would heat it up and bend it back till it it is parallel to the bottom frame rail, then reinforce the area aft of the top suspension mounts with a gusset. I made my own and incorporated holes for a rear rack and a couple of lugs welded on the loop to eliminate the clamps on a craven rack. Much tidier. The down tube that is bent looks like it will take to being straightened with a bit of heat. While the dent looks ugly I don't think it will compromise the integrity of the frame. The Rolls Royce solution there would be fill it with plumbers solder and smooth it out. JB weld would probably suffice.
 
Rear loop droop and down tube dimples are almost as common as belly buttons. Dimple in downtube merely cosmetic so bondo or JBW over or leave for next guy to worry about. If frame bare easiest most accurate way I found was flipping frame over and slamming tail down pretty hard on padded cement. If over done just flip frame and bop it back better to match seat and eye lines. The short strut braces are a good idea for normal loads under 100 lb but if a passenger or cases of beer or feed bags, think about long struts mounted on end of Z plates. Can put two people on loop w/o harming it while still but on even a little bump = bad juju.

Only important thing on frame squareness is allowing assembly w/o much strain. I check this with 3 rods, one thru stem and each iso cradle bolt holes. Some times the crash bars crashes puts a slight twist in down tube that make the front iso mount plates closer together &/or slight tipping misalignment so resists iso mount sliding in. As almost impossible to spread stubby plates so close to cross brace, trial error grinding about only thing to relieve that frustration.
 
After taking a closer look, I think it probably is the Dunstall balanced exhaust and not the 850 system as I'd said earlier.
The Dunstall crossover exhaust had the inconel flex pipe crossover tube like this one. I think the factory crossovers were all solid tubing.
 
As Hobot says If the front iso bolt slides through without any misalignment then the important part of the frame is probably as straight as it needs to be
 
Thanks for this, and for all the continued help L.A.B. In short, the Rick didn't do any work on the gearbox aside from offering that in his experience mildly driven stock configuration gearboxes should last quite a while without the bearing being changed. That said, as with so many other things, I've got the damn bike all to pieces, and have the correct (roller) bearing to hand, so I don't see why I should replace it, even tho I had hoped not to tear apart the gearbox. Having just re-watched the Mick Hemmings teardown and rebuild videos, this seems like a task I can reasonably manage, and think that even without a runout gauge, I should be able to do it just about as well as anyone else has.
SO.... I know there are several Ontarians on this forum, and a handful have been in touch personally over time, so can anyone recommend anybody who is qualified to have a look at the frame and make any adjustments/repairs? Ideally this would be somewhere local to me, as shipping a frame has got to be expensive, and to my eyes, the damage is very minimal.

Photos however are worth more words than I have time for and may help get accurate feedback:

Starting with the rear loop, which on re-assessment, may be a good deal more than 'slightly' bent.

https://photos.app.goo.gl/KzGFgwZWkyluME8y1
https://photos.app.goo.gl/NUJYkwLpE8YwYZBN2

I had thought that perhaps getting the hoop supports from Old Britts might be a good idea to prevent this from being a problem again in future. Opinions?

http://www.oldbritts.com/38_200001.html




And, more importantly, the damage to the front of the cradle downtubes by the now-departed highway/crash bars which came with the bike.

https://photos.app.goo.gl/efs81zbKg4jE27yn1

https://photos.app.goo.gl/K2MjUlmI4eMlxGOt2

As it may be seen, the damage is slight (I think!) and more extensive to one side than the other. My initial thoughts were that this would need to be straightened and perhaps gusseted or sleeved? But as with so many other things, my knowledge of these frames and their eccentricities is slim, and I am relying on what would be considered a standard fix on the double cradle type frames I am more accustomed to.

Apologies as always for the long delays between continued posts in this thread, but the project moves slowly, and I hope is getting done properly as a result. To everyone who warned me, you were all quite right, and rebuilding a Norton is a costly affair! But, I reckon it's been sitting for nearly 40 years now, another couple isn't going to hurt it any.

Also, thanks in advance for any and all advice. Other work continues in the meantime, but the frame and associated repairs represent a major stumbling point just at the moment.

Cheers,
Jon

Jon
1. Very wise to heed L.A.B.'s recommendation for replacing the Layshaft bearing to the one that you have Superblend NJ203E 06-7710S. The Portuguese roller bearings seldom give you any warning when they let go. It locks the rear wheel of the bike up and if you survive the event or drop the bike or injure yourself because of it. IMHO, well it is poor economy. If you need a dial indicator then PM me. I live close to Binbrook Ontairo and I can possibly help if you are near the Hamilton area.

2.
Bring it to a weld shop and have them clamp the tail hoop securely to a weld table and have them apply heat to the area where you see the squat bend and apply pressure back to the original dimensions as per the workshop manual in section F. Section F2 to F3.
The dimensions are there for you to use. The gusset for the rear iso has two holes at top, to run a straight edge to get you back to 240.0mm Once the the rear loop is back to original dimension then get them to install the Old Brits gussets which I recommend for the earlier bikes as the later 73 onward had a small gusset added because of this problem. I still think the old brits is better.
Check the top Main tube and make sure it is not bowed too much(with a straight edge) No humpback, which would indicate that the bike had a front end smack. Hopefully the dents on the front down tubes are just from those clamps that you removed. Make sure these are straight. Again use F frame checking data in the manual. The Commando frames are very light in weight @ 28 lbs (there about) and it doesn't take much to tweak them out of shape from a lay down or front end smack.
Cheers,
Thomas
 
Bending the rear frame loop back is a piece of cake. Follow Hobot's advice. You don't even need heat , it's so easy to do.
 
Bending the rear frame loop back is a piece of cake. Follow Hobot's advice. You don't even need heat , it's so easy to do.
Pete,
It still needs the gussets to be welded so the problem doesn't get repeated. Where is he going to do that??? At a weld shop maybe?
Jon
Rick (Highway Cycle) had some frames straightened by someone in Ontario. I am not sure who, but he did ask around for anyone who had a commando to do a group rate discount thing a while ago. You may wish to ask him.
Regards,
Tom
 
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It's just mild steel after all so after bent back to specs. , a competent welder can put in gussets. Rueben Tang has an even cooler idea which he employed on my MK111 and a few of his builds. By making a strong hoop piece and bolting it to the rear loop rail about half -way along. It arches over the fender . It's about where the passenger sits. When weight is put to the seat here the seat pan rests on it , alleviating weight distribution to the fender and the rear mountings near the tail light. Smart solution and invisible.
 
When I had my gussets fitted and rack lugs, I mentioned to the welder that the steel was thin as standard. He commented that he could see it sagging and backed off with the volts. The rack lugs for the Craven mean that the tail loop is supported down onto the z plates without the plethora of steel brackets and shitty nuts and bolts .
 
Yes , that rear frame loop does not like weight , so there are a few tricks around to move the weight support more forward. Lighter girlfriends , tank bags , supports running to the Z plates , switching from heavy beers to lighter liquor too.
 
As proper gentlemanly operation implies nice throttle ups to fairly tame speed/rpm use may I suggest if diddling in new front iso rubber rings, to tapper narrow the rim of the large ones ~45'ish, leaving ~1/4" flat for distinctly sooner/smoother isolation w/o distracting for out-the-blue sightseeing hazard dodging. Done 2 Combats so far, savoring sense of flying carpet slow poke. For extra stability w/o loss of iso/rpm, slice/dice the old large cushions to add-glue onto rear iso unit. Factory gaps are best compromise for quick isolation vs hinging onset pressing turns. Everynow/then touch the primary case for sense of clever protection.
 
Well, as always, heaps of good advice coming in from all corners. I will try to make this one a little less involved.

I live close to Binbrook Ontairo and I can possibly help if you are near the Hamilton area.
Bring it to a weld shop and have them clamp the tail hoop securely to a weld table and have them apply heat to the area where you see the squat bend and apply pressure back to the original dimensions as per the workshop manual in section F. Section F2 to F3.

Thanks CNN. Indeed I am just down the road from you, in St. Catharines. Another member here from Hamilton came by some years ago, and gave me a hand with dissasembly, since I didn't have any whitworth tools, and I didn't want to round anything off by using the wrong stuff. If I need a hand with anything, I will be sure to get in touch. (PM me contact details if you want to be in touch outiside the forum)
As to the measurements in the Factory manual, I will refer to them once I've got the frame back in the correct general shape. As I mentioned, and the photos indicate, this is the only notable damage I have found on the frame, and it only became apparent some ways into dissasembly. I am quite confident the bike has never been in an accident, as the only folks who've ever ridden it were my Uncle and my Dad, and all that riding was done between '71 and '75. It's a little while in the past, but the poor thing hasn't seen the road since then. (Explains why the 40+ year old tires on it still had the little production hairs sticking out everywhere. And, yes, I have new ones. Just to prevent any concern on that front!)

From all of the above advice, it seems reasonable to go ahead, clamp the thing down and with some judicious use of a blow torch and a rule, slowly bend it back into shape. I suppose this could be done without the heat, but I worry a little about fatiguing the metal without some degree of heat cycling. I would think that even bending things 'back' a little would be enough to deserve an annealing cycle or two, even in mild steel. I guess this makes it sounds easy, and I suspect it will be anything but, however such is the way of all things Commando, it seems.

Only important thing on frame squareness is allowing assembly w/o much strain. I check this with 3 rods, one thru stem and each iso cradle bolt holes.

Good advice, and I will get some type of rod to do just that. At present the front iso is in the frame, if for no other reason than it seemed a sensible place to put it for the moment. No problems at all passing the mounting bolt through it, but using the three rod method combined with a few quick measurements should help me get a better idea how close to square I am. (How close were these frames to 'precisely' square straight from the factory in any case?) Once I have replaced the layshaft bearing and am ready to fit the gearbox again, I will look more closely at the rear iso mounting, but I suspect it will be alright, especially as there is no indication whatever of any damage to the rear end of the bike.

FWIW - I have for the moment, based on a fair lot of reading, decided to chance re-using the original Iso rubbers, and order in a set of the Hemming adjusters. While the washers that were mounted to the bike were pretty much falling apart, and the PTFE washer was nearly disintegrated, the rubber itself in the isos appears free of cracking, oil, damage, and see, quite pliable. I may be proven wrong, but as I am still working within a fairly tight budget by most standards here, I am going this way for now. I suppose at worst, I am wrong and will have some dismantling to do. It is fortunate that this is not my only motorcycle.

install the Old Brits gussets which I recommend for the earlier bikes as the later

Yup. I think I am sold on these, and intend to install their updated side stand mount plate as well while I am at it. For the price, I doubt I could fabricate anything as nice. My C'do came with the clamp on stand, and I don't love the idea of bending or denting more tubes because I kept something that was a poor design to begin with. I do not at the moment have the means to weld them in, but I had the good fortune of getting some TIG training from a site Engineer I worked with a couple years ago, and what better excuse to spend some money I can't afford on a Tig setup? All the limited amount of welding I did there was on various grades of stainless, which I have been led to understand is much more difficult to work than mild steel, so I think I am up the challenge. In any case, problems for a future me. There is much to do done in the meantime.


All advice considered, I have a much better idea of the direction I need to move in to get things rolling agian. Figuratively, and hopefully someday literally as well.
 
It would, of course not be much of a newcomer restoration thread without another question.

I've done enough reading around here on the topic that I would like to go the route of having the rocker spindles drilled through to provide internal oiling through the head, instead of the reach-around hose and a second banjo nut. However, no matter how many threads I have cruised through, there seems to be some ambiguity on whether just the RHS spindle of each should be drilled, or both and I can find no mention of the suggested bore diameter.

It would seem to be intuitive that you would bore a hole about the same diameter of the interior of the hose normally used to supply oil to the head in the first place, but I can think of a couple of fluid dynamics reasons why that might not be the case. I've watched the James Comstock video on how to do it, and while I don't plan on doing this myself, I couldn't make out any indication of the specific size of bit being used. Short of doing some basic measurement to ensure that the centre bored hole doesn't come anywhere too close to the notch in the spindle, I don't really know where to start.

I will have to go through my parts bins and see if I thought far enough ahead to label the sidedness of the spindles upon dissasembly, but I sort of doubt it. In any event, this seems like the best time to figure it out and have it done, while the engine is still all in bits. Deciding to go this route after assembly would be a great deal less fun.

Thanks as always everyone.
Cheers.
 
mild thin steel tube such as rear loop best bent harshly cold, same way as bent to droop. Heated bend is rather weaker. If a loop tube breaks off then cut whole loop off and use a rod or tube jammed inside before welded back then ground down. Wham Bam thankyou mamm. I used big old carpentry square for Peel external braces but be alert to shock motion clearances.
 
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