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Updated
04/03/24
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Updated
02/28/25
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Updated
06/12/25
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Updated
06/04/24
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Updated
09/21/24
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Partial Rebuild July 24
Delivered 03/22/25
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Recommission
Delivered 09/20/24
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Build Oct 23
Shipped 7/13/24
1975 Norton Wiring
Delivered 06/07/24
Blue 69S
Delivered 05/17/24
High Mileage 850
Delivered 03/26/24
Mk3 Engine & Gearbox
Delivered 03/07/23
1973 Customer
BasketCase Build
Delivered 07/15/22
1974 Norton 850
Commando Rebuild
Sold 01/12/21
Updated 06/10/21
Customer Combat
Delivered 09/07/20
First Place Norton 05/18/2025
1972 Norton 750
Commando Rebuild
Completed 05/15/19
First Place Norton 05/16/19
Sold 01/01/20
1972 Norton Wiring
Completed 07/19/18
1974 Norton Wiring
Completed 07/27/20
Customer Combat
and 69S Builds
Closed 10/18/23
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 | Saturday, June 14, 2025 |
March 15, 2025 Coming March 19, 2025. I sold a 1974 Triumph Trident for a Norton
MKIII Commando partly rebuilt basket case and a little cash. That Trident is documented
here.
March 19, 2025 The MKIII arrived today. It has lots of new and restored parts and
seems complete. I haven't spent much time looking it over yet. The gearbox needs
to be built and I'll do that first. The bottom end of the engine is built and
in the frame. The cylinders are bored - haven't looked yet if they need to be
painted.
It is a black, matching numbers Roadster.
Started on the gearbox. Other than a couple of studs and nuts everything is there
and in good shape. However, the shell looks "rider good" and when I rebuild
a bike I want all cases to look new. So, I've stripped it and have started my
beautification process. Normally, that would only take me an hour but working one-armed
really slows things down!
March 20, 2025
It's always interesting and always different when you start on a bike. Besides
the actual beautification process, I makes sure that every threaded hole is open
clean and the stud, bolt, or item that screws into each hole will go in with
fingers only. Since I had studs keeping the holes clear for the seven studs
that hole the inner case to the shell, an old drain plug in the drain
hole, and an old neutral switch in the neutral switch hole, those holes were
easy. That only left the index plunger housing, selector fork shaft, and some
checking:
- Index Plunger Housing. That hole was easily cleared with a bottle
brush.
- Selector Fork Shaft - see the first picture. the four on the left are correct,
the one on the right came with this bike and was poorly hack sawed off. It did
not want to start in the hole and would not start from the outside either. So, I
used on of the other ones I had. Rough starting from the inside but started
easily from the outside. Used it to cleanup the first couple of threads on the
inside. Now all four of the good ones start and thread in without problem from
the inside and the ones that came with this bike is in the metal recycle bin. I
have no idea why someone shortened it!
- The second picture shows the other issue I encountered. At some time in it's
life, the nuts were overtightened and raised a lip around the stud (orange
circle). Also, there were scratches in a few places across the mating surface
(orange oval). Finally, with the location studs removed (PITA), there was a
.002" gap between the shell and my surface plate. A few seconds with 120 grit
paper, about one minute with 220 grit paper, and about two minutes with 320 grit
paper and all is resolved. With a good gasket, it probably would have sealed but
now I know it will.
- Now I'm stuck for little while. The camplate switch "button" is
badly scored and I'm out of stock on them so I have to wait for my next AN order
to be able to assemble the gearbox. I have quite a few used camplates but none with
the MKIII neutral switch "button" in usable shape.
March 27, 2025 I've had a lot of medical stuff going on for my knee replacement
on April 1st. It's still not confirmed that it will happen – PITA! I've
been rebuilding the gearbox as I've had time.
The quadrant "button" for the neutral switch was badly damaged and I didn't
have one, so I order one. That is now installed. The neutral switch that came with
the gearbox was missing one terminal, so it had to be replaced. I stock the Lucas
switches, but they do not work "out of the box". I learned/fought that
on the last MKIII gearbox rebuild. This time I was stuck. The original switch plunger
sticks out of the switch body about 3/16". The Lucas one sticks out about 3/8".
With it adjusted so it just closes, it will catch on the "button" and
prevent you entering neutral. It took two tried, but I cut the plunger in half and
used a Dremel and fine sandpaper to put a smooth ball shape on the remaining plunger.
The first try came out too short and the switch would not close. On the second try
I got it perfect. Now with the switch adjusted so if just closes when on the "button",
it does not touch the quadrant on other gears and hits the "button" part
way up so no binding. With the plunger as supplied the binding between the plunger
and switch body was way too much.
Next problem. The bike came with three main shafts. One is clearly used and form
the middle to the two ends is off by 0.040". the next looked nearly new but
was off 0.020" The third is new from Andover Norton and perfectly straight.
Another problem. The bike came with two layshafts. Both are in perfect shape except
that someone turned the bearing end down slightly – probably to make the slip into
the original ball bearing. The inner race for the layshaft roller bearing would
slip on easily. They probably would have worked and with bearing set they certainly
would work, but I didn't want to wait a day for that to set up. So, I got a
layshaft from stock and used that.
March 28, 2025, Got a call today, the surgery is on for Tuesday. Of course, I was
told that the scheduler would call in the afternoon today and let me know what time
to be there – didn't happen!
More gearbox troubles. See the video below. I really need a phone stand! Anyway,
the kickstart shaft and its bushing that came with the bike are not usable. The
shaft OD measures 1.121" in one direction and 1.123 in the other. The bushing
ID measures 1.128" and is round. Also, the pawl is the most worn I've ever
seen!
I checked a new shaft, and it is 1.122". I went though my bushings and found
a good one with an ID of 1.126". I found a good used shaft in my gearbox parts
that is 1.122" and it has a like new pawl.
OK, time to check/correct the layshaft end play. It has .055" so too much.
Of course, I can't find my collection of shims, so I ordered more from McMaster
Carr and the gearbox is on hold for now unless I find my shims before Monday.
Next problem. The sealing surface of the inner cover was worse than the shell, so
I corrected that and went about checking the screw holes used to hold on the outer
cover. Two holes were fine, one had to be chased since the screw would only go in
about 3/16", I thought I would have to HELICOIL the others as the first part
of the threads was bad, but once chased the more internal threads are fine so it
will be OK.
March 30, 2025 Since I'm stuck on the gearbox until shims arrive, I started
on the engine yesterday.
I expected the bottom end to be ready to go but when I uncovered it, not so much.
Basically, greasy grimy gopher guts! With basically no right arm and a hurt left
arm, getting it out of the frame was not fun but I did it. I was able to do it because
my steroid shot from Thursday morning had not worn off yet; but, of course I hurt
both arms more in the process.
Next was getting the timing side apart. What a nightmare! The camshaft nut would
not come loose with my longest breaker bar, even with a fork tube to extend it.
Then I tried heat - no help. Then my air wrench - no help. So, it was time for the
big electric driver capable or 450 ft. lbs. I have never found anything to resist
it and this was no exception. It came right off. OK, now onto the drive worm gear
on the crankshaft - the big gun was needed for it as well. OK, home free? Nope!
I had three pinion pullers when I started. My very old Triumph one that I modified
to work on Triumph and Norton - it broke. Then I had
a Norton one that I modified to actually work (the "legs" are too thick),
it broke. OK, last try. I had a new Norton puller I got when I bought someone out.
Of course, it was too thick to work so after a bunch of grinding I finally got it
to grab and thankfully it pulled the pinion without breaking! Another interesting
thing is that the
outer camshaft bushing was very loose in the case - I'll have to figure that
out!
Whenever I'm rebuilding a Norton other than 72/73 750s, I send the cases to
Colorado Norton Works for their breather upgrade. To save time and accomplish something
while in the hospital, I'm going to have them do the case cleanup as well. So,
I stripped everything from the cases today and they are box and ready to ship tomorrow.
The insides of the engine are so grimy that I assume the crank needs to be cleaned
out so that will be the next step when I'm able. The first picture below is
after I got the parts out and cleaned up a lot of the grime!
May 4, 2025 Before my knee replacement surgery I did take the crank apart and
cleaned/inspected it. It’s I good shape. I couldn’t put it back together because
I didn’t have the stud/nut set. Those parts came in the day after my surgery.
I’ve only been to the shop a couple of times before today to get things. Today
was the first day I worked on something there. The gearbox is assembled except
the outer cover. The gear ratchet plate is missing (or I haven't found it) and
the outer cover is not only ugly, but someone drilled out the location pin
holes. Those two parts are expensive, so I'll check options before ordering
new.
So, I can walk, get in the car, and drive. Everyone says I'm doing great. I
hoped to be a lot further along at this point!
May 18, 2025 Lots of doctor appointments a little progress but not much. I had to
cancel my shoulder replacement for now since I can't get up fro a chair without
arms and I will lose use of my right arm from three months after the surgery.
I got the parts I needed to finish the gearbox including a new outer cover from
Andover Norton. I was quite disappointed in it. It's functionally fine, but
I ended up spending a lot of time polishings it. It was not the quality I'm
used to form Andover Norton! By the time I had it looking acceptable, I was out
of steam.
May 19, 2025 I'm moving like a snail, but I did get the gearbox finished today.
May 20, 2025
I spoke too fast yesterday. I had put the outer cover on the gearbox and tested
the gear change, but I had not tightened but the screws. Today, I took out the crappy
original screws and out put in stainless Allen Cap screws with anti-seize. First
I tightened to 30 in-lb. - no problem. Then when tightening to the final torque
of 50 in-lb, the bottom three all spun in the threads. See the gearbox section of:
Norton
Torque. Fortunately I had a 1/4" BSF thread repair kit so I installed
inserts in all three.
I put in 5oz of 80W90 and turned the gearbox every which way. Since it will likely
sit for quite a while, before installing, I'll drain it and once in the bike,
fill it properly.
That done, I finished cleaning up the crankshaft and put it together with a new
stud and nut set, but I haven't torqued it as I'll have to have help to
do that with my bad shoulders/arms.
May 23, 2025 Next issue! I work on way more pre-MKIIIs than MKIIIs. I always use
a new stud/nut kit when I reassemble the crank. The MKIII set is supposed to
have:
1 – 06.5671
4 – 06.6609
2 - 06.6607
but had:
1 – 06.5671
6 – 06.6609
0 - 06.6607
I didn't notice it when I put it together but I was wondering how the crank
was
aligned to I checked - oops - AN made a rare mistake.
Fortunately I had two 06.6607 in stock and put them in.
Now for the real shock! I was able to torque it. It took forever getting situated
for each so I had the strength to do it without too much pain.
Then I started on the conrods. They are in decent but ugly shape so
I'll clean and buff them. The disappointing part is that the shells were clearly
put in the rods without cleaning and the shells that are probably nearly new are
not good. Fortunately, the journals are good and I have a new set of shells in stock.
May 24, 2025 Cleaned up the conrods and then installed on the crank. I did my usual
tests and the rods feel perfect on the crank. I didn't worry about a mirror finish
on the rods, but they are clean with no stress risers.
May 25, 2025 My plan for today was to go to the shop rested and put the bottom end
together. I partly accomplished that. First job - find the camshaft in one of the
boxes. Found it - too poor condition to use and I sold the last one I had in stock
so the bottom end could not go together but I continued on.
Installed the main bearings, crankcase location dowels, top studs, and timing intermediate
gear spindle. I mentioned on March 30th that the outer camshaft bushing was loose
in the case. I had two new bushings in stock, and they were a proper fit in the
case so I installed them after checking that they fit the old camshaft well. Of
course, once in they shrunk and the camshaft would not go through them so I broke
out the 7/8" reamer and corrected that. Then I put the cases together with the old
camshaft to check that it would spin freely as it is easy to put in new bushings,
ream them and then be out of line. This time it was fine.
I put a camshaft on order so I'll be stuck now until Wednesday or Thursday. I
guess I'll use the time to inspect the cylinders and pistons to decide what needs
to be done there. At a minimum I think they will need to be painted.
May 26, 2025 Only a little progress today. The cylinders are bored .040" over and
they have been painted but need some touch up. The tappets look good but have a
slight mark across the face. Since I'm installing a new cam, I'll surface
them. The tappets were not moving smoothly in the tunnels - a small amount of rust
developed. That's easy to cleanup. There are some small spots of rust on the bottom
of the cylinders (not in the bores) so I'll probably give it a light blasting
to cleanup the tunnels and those spots and then will give it a new coat of paint.
Also, the top gasket surface is stained - I'll spend a little time with fine
sandpaper and the surface plate cleaning that up.
May 28, 2025 One step forward ... The bike came with cylinders bored and honed to
.040" based on a pair of good used pistons. Those pistons came with a set of
Hasting-type new rings installed and there is a set of new Hastings rings as well.
I normally install a new set of Hepolite pistons but decided there was no need in
this case (or so I thought).
The piston marked left was in pretty good shape and only had some minor marks on
the skirt but also had some minor dings in the bottom edge of the skirt in-line
with the pins. Spent about 30 minutes removing those dings, polishing the piston,
and then cleaning it well. Next I checked the skirt clearance. A .003" would
go but not a .004". I like .004"-.005" on fresh bore and hone
so I wasn't pleased but could hone it for better clearance. Then I started on
the other piston. One circlip was broken off in the piston and after an hour of
trying to get it out, I gave up on that set of pistons.
I had a new set of .040" over Hepolite pistons in stock. I checked the skirt
clearance: .004" went in and .005" would not so that was good. Then I
checked all the rings gaps and they were all in spec.
May 30, 2025 I'm feeling like I'm 90 this evening.After spending the morning
on
customer IT issues, I went to the shop at noon with my stepson who was visiting.
He did lots of work, I sat a lot and did what I could. We were at ti for seven
hours.
I've been wanting to rearrange the shop for a long time, and he wanted to get
back to rebuilding his 74 MK2A. We finished the power unit months ago and he
had his frame painted so it was time. But first, we needed to get my 74 MK2A off
the table and on my lift so we could use the table for his bike. This caused
moving every bike in the shop at least once. Once all that was done, we installed
new steering bearing and then put his power unit on the now free table and lowered
the frame over it. Now when he comes to visit he can make progress on it and if
I have free time I can do some too.
So, I didn't accomplish anything on this bike!
June 1, 2025 Progress! The bottom end is together and the engine is on the stand
and lazy susan. I started on the timing chest but am stuck for now waiting for
some parts from cNw. When they machine the cases for the reed valve they also
do Jim Comstock's timing check mods and they were out of the plugs I need to
install - that can't be installed with the timing chain installed.
The cradle is powder coated which I really don't like. It was masked more or
less per the Old Britts instructions but all the washers were too big. So
painting the bare areas is a mess. I love power coat - just not on cradles. If
I had another MKIII cradle I would put this on aside and use it painted it like
I always do. I may scuff up the powder coat and paint the whole thing - haven't
decided what to do.
June 2, 2025 Not a lot of progress. I cleaned up the timing chest parts,
installed the missing chain adjuster studs, and checked the oil pump. The oil
pump was clogged and not turning right. The screws were the tightest I've ever
come across. Finally got them out. The internal driving gear is damaged and I
don't have one so I spent the next hour searching eBay and making offers on
oil
pumps. Besides this bike I have two more to build and there's a chance they
will
need pumps too so I'm trying to buy three.
June 3, 2025 Well, that dummy doesn't understand business so I found three more
oil pumps for a little less! Attacked the cradle today - took forever. After
cleaning, I sanded it all with 220 grit paper. That barely touches powder coat but
does help with the transition from powder coat to bare metal. Then I changed
out the bead in my blast cabinet for glass abrasive. That got all the bare metal
ready for pain and improved the powder coat surface more for paint. Then after a
through cleaning with denatured alcohol and blowing with air, I masked it for
paint. I use VHT Gloss Rollbar and Chassis paint. It requires no primer and is
tough an heat resistant. All coats must go on within an hour or you have to
wait seven days for the next coat. I was way too tired to do the painting today
- probably
tomorrow.
June 5, 2025 Got all setup to paint the cradle and then it happened. Big ol me
hit the concrete floor very hard. The heaviest impact was my left hip (bionic),
left ankle took damage, left toes bent under and scraped, and left knee (replaced
April 1st)
whiplashed. So, there I laid surveying the damage and wondering if and how I could
get up. My medical alert that is supposed to detect falls didn't. I pushed the
button - crickets. No point in yelling for help - no one to hear. So, after
about 30 minutes, I got finally got to my hands and knees which is really not fun
with my knees and using a chair and a storage bin was able to get off the floor.
After sitting a long time I finally decided to at least get the cradle painted
since the humidity was scheduled to be high for the next three days. It's done
and I hope I did a good jobs. So, my knee that didn't hurt now hurts like hell.
My ankle is swollen but I think OK. My bad left shoulder is worse and my really
bad right shoulder is even more bad now.
June 6, 2025 Sleeping last night was a non-starter. Was in pain no matter how I
laid. the only pain killer that actually works for me is aspirin but I'm not
supposed to take it. Around 4am, I took 1000mg and finally got some sleep. I'm
somewhat better now but walking is difficult so I didn't work n the bike today.
June 7, 2025 Worked in the shop for a few hours but no on this bike. My stepson
was here and we worked on his MK2A.
June 8, 2025 The cradle paint was hard enough so I installed the gearbox in it.
I'm hoping the parts from cNw arrive soon so I can attached the engine to the cradle.
Once again I figured out how to torque the bolts with bad shoulders - ouch!
The used oil pumps I ordered arrived yesterday. Both need servicing and one is from
a
pre-Commando
but has the "6 start" drive gear so it will work. It normally takes me about 30-40 minutes to fully service a Commando oil pump. The first one took over two hours! The last "person" to service it was a gorilla and it had a bunch of RTV in it and it would not turn a full revolution. Once I got it apart, I had to dress the driving shaft (mushroom'ed) and replace the un-driven shaft as well as the return driven gear (why I keep old bad pumps). I surfaced all surfaces and put it back together - it feels great!
Once I had that one done, I was too tired to do the other.
June 9, 2025 Restored the second oil pump - that went a lot easier!
Round and round she goes where she stops only the surface plate knows! I
mentioned before that the cylinders are nicely bored but must be repainted. If
the cylinder/head mating surface is not flat, it must be corrected before
painting or the paint will be damaged on top when surfacing it (unless you're
lucky enough to have a mill). I was shocked that the area between the cylinders
was .0015" lower than the outside. So, 150 grit paper on the surface plate and
90 minutes of rubbing/twisting, checking and repeat. The surface is now
perfect. The center is still stained but the surface is flat. The cylinders are
now masked for blasting - I don't want the nicely honed surface hit with grass
abrasive. Once I get all loose paint off, I'll wash in hot soapy water and
immediately blow dry and oil the bores. Then mask again and paint with VHT Gloss
Barrel Paint.
June 10, 2025 The parts from cNw arrived today and they are installed as well as
the rest of the timing side except the cover - I can't find that. There are a
lot of boxes and bins of parts for this bike and going through them looking for
parts is hard for me right now. I should have emptied the bottom of the mobile
table I'm using and put the parts for this bike there. After all, that's why I
built the tables that way! Look here.
The cNw breather kit comes with four black plugs you install in the timing chest along with a steel one with a chrome end to replace the original breather connector. There are two large, one medium and one small plugs. The MK3 cases already have the spot for the small plug blocked off so it is not used.
The first picture shows where they go (with red Locktite) and the second shows them, the breather plug and timing parts all installed.
June 11. 2025 Surprise, surprise. I planned on just blasting the cylinder bare and rust spots. However, the paint is weak and most was coming off easily. I spent about 40 minutes on it until my new knee could take no more. It is mostly bare metal now. Next time I feel up to it, I will inspect and blast the rest off. Then I installed the cNw breathers. Another surprise: the MKIII oil tank breather return is 1/2" so the cNw breather is also 1/2". The older ones are 3/8". So, I ordered some Gates 1/2" SAE 100R6 transmission oil cooler hose for it. I was shocked how the price went up! The same hose in 3/8" that I bought 25' last cost $65.00 - this 3' piece cost $21.00
June 12, 2025 Well, when I looked at the cylinders in good light it was time to try again! They are clean now and in the paint cabinet on the Lazy Susan but I was too tired to do the painting today. Normally blasting and painting cylinders is a few hour job, but between my foot, knee, and hip and bad shoulders everything is hard!
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Copyright © 2003-2025
Greg Marsh Enterprises
8116 Arlington Blvd. #171, Falls Church, VA 22042
(703) 200-4025 marshg@gregmarsh.com
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