RRussellTx - 1974 Commando 850 Project

RussellTx

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Hi,

New to the forum and to Nortons for that matter.

My great uncle has a 1974 Commando 850 that he bought new. It had some engine troubles in the 80's and has been in my Dad's garage ever since. I finally got his permission to drag it over to my house and fix it back up. Below are a couple of pictures from the 70's and this last week. The task is to get it back to the original photos!

Please let me know if there are any threads or parts vendors that I should be aware of as I embark on this journey.

I built a Factory Five Roadster and recently rebuilt my neighbors 1966 Mustang Convertible (Also still with the original owner).
I know how helpful these forums can be.





Thanks!
Richard
 
If you check out the restorations page you’ll find build threads by folk that can be very interesting and informative. I’d definitely suggest starting a build thread there, you’ll get lots of advice and input, irrespective of whether or not it was wanted !

I rebuilt my 74 and posted about it, sadly a lot of the pictures got lost by the photo bucket situation, but there may still be something of interest:

 
Welcome to the forum.

Nice bike. In case you don't know that is a Roadster Mk2 850 Commando. It will have been built in the 1974 calender year. There are a few little parts differences over the years so it's good to know the exact model. You might hear people talk about a Mk2A model which was built at the same time which has a few differences notably the airfilter box and battery mount but your is definitely a Mk2 with the "hamcan" airfilter.

Mine is exactly the same model and probably had the same tank colour when new. Repainted black and gold now because the tank was damaged.

Sounds like you have the skill set to handle getting the bike back on the road.

A few thoughts if your interested.

First off tools. These bikes have both AF and whitworth/BSF bolt sizes. The frame is mostly AF but if you get into the motor and gearbox you will need whitworth spanners. Koken make a good set of sockets which will get down into the nuts on the head. You will also need a set of whitworth ring and open end spanners.

These bikes have lots and lots of upgrades available and some can definitely get expensive. Sounds like your young and therefore don't need an electric start upgrade that us 70 year old need. Good thing because they are seriously expensive.

However I would definitely look at a front brake upgrade. The first step is smaller piston in the front brake master cylinder. Andover sell an upgraded unit. There are also complete new front brakes available from several places but again expensive. RGM Norton in the UK sell high performance rear brake shoes which I have found to be by far the best rear brake upgrade.

The other main improvement is to fit an electronic ignition unit. There are several available. I use a Pazon mostly because they are made in NZ. You can also get Boyer and Tri-Spark.

Carbs may also be an issue but if the bike hasn't done many miles the originals may still be OK. Greg Marsh sounds like the go to guy in the USA for carbs.

Anyway those are the upgrade areas I'd look at for a good usable bike I think. You can go silly like I have done myself but there is a big plus in keeping things close to standard I think. Especially if your not in yiur 70s and needing all the help you can get.
 
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Looks like a great project, it's all there, do you know what caused the bike to have engine troubles back in the 80s to be put away, could just be a simple blocked pilot jet or something simple as normally the 850s were a reliable bike if maintained right, there are a lot more upgrades these days compared to what was around in the 70/80s, but a good pull down and go through be the go to find out what happened for it to just be put away for all these years, you never know it might be just a good clean up and make sure everything is in working order, but everything will need a good pull down and going through and replace anything that is not right.
But keep it simple as with new upgrades you will need deep pockets, with time you might have a gem of a bike, look forward to following this project, and if you run into problems walk away and think about it and ask here for advice, be good to see it back on the road and have fun, we all dream about finding a gem for the next project.
And use the right tools.

Ashley
 
Welcome to the forum.

Nice bike. In case you don't know that is a Roadster Mk2 850 Commando. It will have been built in the 1974 calender year. There are a few little parts differences over the years so it's good to know the exact model. You might hear people talk about a Mk2A model which was built at the same time which has a few differences notably the airfilter box and battery mount but your is definitely a Mk2 with the "hamcan" airfilter.

Mine is exactly the same model and probably had the same tank colour when new. Repainted black and gold now because the tank was damaged.

Sounds like you have the skill set to handle getting the bike back on the road.

A few thoughts if your interested.

First off tools. These bikes have both AF and whitworth/BSF bolt sizes. The frame is mostly AF but if you get into the motor and gearbox you will need whitworth spanners. Koken make a good set of sockets which will get down into the nuts on the head. You will also need a set of whitworth ring and open end spanners.

These bikes have lots and lots of upgrades available and some can definitely get expensive. Sounds like your young and therefore don't need an electric start upgrade that us 70 year old need. Good thing because they are seriously expensive.

However I would definitely look at a front brake upgrade. The first step is smaller piston in the front brake master cylinder. Andover sell an upgraded unit. There are also complete new front brakes available from several places but again expensive. RGM Norton in the UK sell high performance rear brake shoes which I have found to be by far the best rear brake upgrade.

The other main improvement is to fit an electronic ignition unit. There are several available. I use a Pazon mostly because they are made in NZ. You can also get Boyer and Tri-Spark.

Carbs may also be an issue but if the bike hasn't done many miles the originals may still be OK. Greg Marsh sounds like the go to guy in the USA for carbs.

Anyway those are the upgrade areas I'd look at for a good usable bike I think. You can go silly like I have done myself but there is a big plus in keeping things close to standard I think. Especially if your not in yiur 70s and needing all the help you can get.
Wow! Great i
Welcome to the forum.

Nice bike. In case you don't know that is a Roadster Mk2 850 Commando. It will have been built in the 1974 calender year. There are a few little parts differences over the years so it's good to know the exact model. You might hear people talk about a Mk2A model which was built at the same time which has a few differences notably the airfilter box and battery mount but your is definitely a Mk2 with the "hamcan" airfilter.

Mine is exactly the same model and probably had the same tank colour when new. Repainted black and gold now because the tank was damaged.

Sounds like you have the skill set to handle getting the bike back on the road.

A few thoughts if your interested.

First off tools. These bikes have both AF and whitworth/BSF bolt sizes. The frame is mostly AF but if you get into the motor and gearbox you will need whitworth spanners. Koken make a good set of sockets which will get down into the nuts on the head. You will also need a set of whitworth ring and open end spanners.

These bikes have lots and lots of upgrades available and some can definitely get expensive. Sounds like your young and therefore don't need an electric start upgrade that us 70 year old need. Good thing because they are seriously expensive.

However I would definitely look at a front brake upgrade. The first step is smaller piston in the front brake master cylinder. Andover sell an upgraded unit. There are also complete new front brakes available from several places but again expensive. RGM Norton in the UK sell high performance rear brake shoes which I have found to be by far the best rear brake upgrade.

The other main improvement is to fit an electronic ignition unit. There are several available. I use a Pazon mostly because they are made in NZ. You can also get Boyer and Tri-Spark.

Carbs may also be an issue but if the bike hasn't done many miles the originals may still be OK. Greg Marsh sounds like the go to guy in the USA for carbs.

Anyway those are the upgrade areas I'd look at for a good usable bike I think. You can go silly like I have done myself but there is a big plus in keeping things close to standard I think. Especially if your not in yiur 70s and needing all the help you can get.
Very helpful information!

Funny you mention the air filter box. That has been my biggest struggle since I started the tear down this morning. I have been following the workshop manual until I run into a special tool and then I order the tool and move to something else. The manual says the air filter face plate will drop out of the bottom but that was not happening easily. I finally got it out but there was baffling that was in the way. I will need to figure out a better trick for when that goes back in!

I would also like to upgrade the oil and fuel lines. They are shot, and I see some pretty slick setups on some of the Youtube vids. I look forward to you guys helping me spend my money!

Here is a pic of the air filter cover.



 
Looks like a great project, it's all there, do you know what caused the bike to have engine troubles back in the 80s to be put away, could just be a simple blocked pilot jet or something simple as normally the 850s were a reliable bike if maintained right, there are a lot more upgrades these days compared to what was around in the 70/80s, but a good pull down and go through be the go to find out what happened for it to just be put away for all these years, you never know it might be just a good clean up and make sure everything is in working order, but everything will need a good pull down and going through and replace anything that is not right.
But keep it simple as with new upgrades you will need deep pockets, with time you might have a gem of a bike, look forward to following this project, and if you run into problems walk away and think about it and ask here for advice, be good to see it back on the road and have fun, we all dream about finding a gem for the next project.
And use the right tools.

Ashley
The engine just would not turn over. They assumed it was vandalism with someone pouring something in the spark plug holes. They tried everything to get it to break free with no love. 40 years later and I don't have any hope for it to be a quick fix. I put a camera down there and it was not good! I emailed Ella and Fred from OldBritts.com earlier this year and they still happened to have a set of the standard barrels so I picked them up. Also found some OEM pistons and rings. I just need to figure out how to get the engine apart with stuck pistons...

Anyway, The journey starts today...
 
Don't get rid of the original paint. I haven't seen too many Blue 74's. I have one waiting to be redone in worse condition than yours. 1974 Roadster, vin 31604X, June manufacture.
 

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Hi,

New to the forum and to Nortons for that matter.

My great uncle has a 1974 Commando 850 that he bought new. It had some engine troubles in the 80's and has been in my Dad's garage ever since. I finally got his permission to drag it over to my house and fix it back up. Below are a couple of pictures from the 70's and this last week. The task is to get it back to the original photos!

Please let me know if there are any threads or parts vendors that I should be aware of as I embark on this journey.

Thanks!
Richard
It appears to have original paint on the tank and side covers. If you carefully clean it with soap and water you may find that a carnauba paste wax will bring it back to life. The paint will have no clear coat and the pin stripes were hand done after the tank painting was done so you don't want use any sort of abrasive it you can help it. If it must be "cut" to get rid of haze, then the finest polishing compound followed by the wax.

If you don't care about it and want it painted then I suggest buying a new tank and having that painted - someone will want your set if they clean up.

If the crank won't turn, it may not be the pistons. I recently took apart and engine that was stuck solid. Once the head was off and the cylinder fasteners were off, they lifted off without a lot of trouble - the big-end shells were hard stuck to the crank. With the cylinders off, the crank was more-or-less free, but the rods were not. Split the cases, removed the big-end nuts and drifted the bolts out. The rods then came free. Shockingly the rods and crank were OK, just needed new shells, the journals polished, and new main bearings! There's a first for everything and I have no clue how they got stuck like that..
 
Wow! Great i

Very helpful information!

Funny you mention the air filter box. That has been my biggest struggle since I started the tear down this morning. I have been following the workshop manual until I run into a special tool and then I order the tool and move to something else. The manual says the air filter face plate will drop out of the bottom but that was not happening easily. I finally got it out but there was baffling that was in the way. I will need to figure out a better trick for when that goes back in!

I would also like to upgrade the oil and fuel lines. They are shot, and I see some pretty slick setups on some of the Youtube vids. I look forward to you guys helping me spend my money!

Here is a pic of the air filter cover.



You have the genuine original airfilter face plate with the noise suppressing baffling inside. Most plates are missing those baffles these days and I do not think you can buy a replacement that still has that baffling.

So definitely original but baffles removed by many because it does make fitting a filter a big challenge. Usually I would remove the carbs before taking that filter plate out. Remove the Allan screws which attached the carb manifolds to the head first. You cannot get at the inside nuts that hold the carbs on. You will need to cut down an Allan key to get at the inner Allan screw. This is a well known Commando battle.

Read the manual very carefully when taking the head off. Check very carefully you have ALL the nuts and bolts off. Do not forget the ones that come up from underneath including the one at the back. You may need to slim down your spanner to get it. Andover sell a special spanner to undo it but I have found most spanners will fit. Its a Whitworth head sized nut. Sorry I don't remember the specific size. Someone will.

Your bike looks very complete. The main ignition switch is gone and rear indicators I think. But most is original.

Sad news about the motor. May be a battle getting the head and barrels off. Soak it with diesel maybe.
 
Take a photo of the ring slots on your new pistons and post it. There was one type of piston with long slots behind the oil ring and the skirts were prone to falling off. You need to check.

By the way my engine no is 3192XX . An August 1974 build. Your no should be within about 10,000 of this up to about 321000 max. They then jumped to 325,000 when the Mk3 models started.

These are two manuals I use. I guess yiu have the workshop manual but the Norman White Restoration manual is good too because it is more of a walk through with lots of background. Norman White was a works mechanic for the Norton race team and still owns a Norton service company in the UK.

I was looking at your photos again. Your bike is extremely original. Not many like that out there these days. I'd recommend lots of photos noting things like cable and wiring lays etc. You have the potential for a very nice original bike there.
 

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Take a photo of the ring slots on your new pistons and post it. There was one type of piston with long slots behind the oil ring and the skirts were prone to falling off. You need to check.

By the way my engine no is 3192XX . An August 1974 build. Your no should be within about 10,000 of this up to about 321000 max. They then jumped to 325,000 when the Mk3 models started.

These are two manuals I use. I guess yiu have the workshop manual but the Norman White Restoration manual is good too because it is more of a walk through with lots of background. Norman White was a works mechanic for the Norton race team and still owns a Norton service company in the UK.

I was looking at your photos again. Your bike is extremely original. Not many like that out there these days. I'd recommend lots of photos noting things like cable and wiring lays etc. You have the potential for a very nice original bike there.
Is that the number on the tag on the head tube? Mine is 313535 manufactured in 3/74.

Also, here is a shot of the pistons I have.. Hopefully they are good.

I just ordered the Norman White Book. Also, here is a pic one the ones I have so far.





 
It appears to have original paint on the tank and side covers. If you carefully clean it with soap and water you may find that a carnauba paste wax will bring it back to life. The paint will have no clear coat and the pin stripes were hand done after the tank painting was done so you don't want use any sort of abrasive it you can help it. If it must be "cut" to get rid of haze, then the finest polishing compound followed by the wax.

If you don't care about it and want it painted then I suggest buying a new tank and having that painted - someone will want your set if they clean up.

If the crank won't turn, it may not be the pistons. I recently took apart and engine that was stuck solid. Once the head was off and the cylinder fasteners were off, they lifted off without a lot of trouble - the big-end shells were hard stuck to the crank. With the cylinders off, the crank was more-or-less free, but the rods were not. Split the cases, removed the big-end nuts and drifted the bolts out. The rods then came free. Shockingly the rods and crank were OK, just needed new shells, the journals polished, and new main bearings! There's a first for everything and I have no clue how they got stuck like that..
Thanks Greg. I spent some time cleaning up the painted bits today and they are in great shape. They have some crazing that is only barely visible in full sunlight. The big flake metallic really pops in the sun! I'll definitely get them cleaned up and waxed and keep the original paint.

I'll reach out when I figure out what I need!
 
One of my favorite parts suppliers through the years has been Waldridge Motors out of Ontario. Often the exchange rate makes their prices very competitive. They also usually have an end of year sale. They carry a wide range of the Andover Norton parts. Because they have them shipped in by the container they are generally cheaper than having them shipped directly to you from AN in the UK except maybe for very small items. Seeing the TX at the end of your name I assume you must be from somewhere here in TX?
 
Is that the number on the tag on the head tube? Mine is 313535 manufactured in 3/74.

Also, here is a shot of the pistons I have.. Hopefully they are good.

I just ordered the Norman White Book. Also, here is a pic one the ones I have so far.





I cannot really tell from those photos of the piston because you need to look behind the oil ring. However I have attached a photo of a bare piston that shows the slot. I mentioned the issue because I don't know where your replacements came from. If it was Old Brits you should be fine. I'm in NZ so not so familiar with the US retailers sorry. But there should be US guys on the forum who can say.

Yes that number should be on the red tag on the steering head, the left side crankcase just below the barrel and also along the top of the gearbox shell under the carbs. All noes should be the same. In NZ anyway that number would be on your registration papers and is used by the licencing authority. Again in the US you may need local advice because from the little I have read it can be a nightmare if you don't have proof of ownership. Since it's been in your family for years I'm sure you will be fine.

That number is very consistent with the dating info Greg Marsh had on his site.


You have a great collection of manuals. Is the bottom left one without a cover a Clymner manual? They are good. The Haynes manual is probably the least useful. I have just been reading my Norman White one again. It's good because he takes you through known issues and recomended procedures. Plus gives a lot of info on different models so you can better decide if you have the right parts
 

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Wow! Great i

Very helpful information!

Funny you mention the air filter box. That has been my biggest struggle since I started the tear down this morning. I have been following the workshop manual until I run into a special tool and then I order the tool and move to something else. The manual says the air filter face plate will drop out of the bottom but that was not happening easily. I finally got it out but there was baffling that was in the way. I will need to figure out a better trick for when that goes back in!

I would also like to upgrade the oil and fuel lines. They are shot, and I see some pretty slick setups on some of the Youtube vids. I look forward to you guys helping me spend my money!

Here is a pic of the air filter cover.



Of course, it’s personal taste, but IMHO fancy braided lines with big bulky fittings are both unnecessary and visually out of place on a Commando. AN do pre cut lengths of the lines, and proper pre assembled fuel lines, etc. But it’s easy enough to make your own from stock tubing.

Out of interest, what kind of build are you going for? Stock, resto mod, etc ?

Looking at the quality of your car builds, you might wanna peruse the offerings of Matt at cNw:

 
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