Reviving a Norton

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rvich said:
Is this likely to be the only Commando you will ever own? You will put a lot of work into getting that bike going and a fair bit of money. Most of us will not be able to give you any advice on problems you encounter because of the custom one-off build. It means you will be solving any geometry problems yourself and are basically designing a motorcycle from the ground up. If it doesn't handle well when finished, the frame will be suspect, despite the fact that it might be something else. If it were me, I would find a straight frame, build a stock or reasonably close to stock bike and I would keep that frame as a collectible. Just my two cents. But I think it makes even more sense to get a stock frame if you think you might want to one day sell the results of your efforts.

There are a few members on here who have a lot of experience with Seeley frames and Featherbed frames. If nothing else, get the frame stripped down. Take a lot of photos and measurements and then get some advice from people who know frames. Maybe put the frame in the back of the truck and go visit NYC Norton.

You gotta wonder why this bike sat for so many years if it was a good idea to start with.

Russ


+1 Many times people have an idea and begin to execute it. Those ideas are not always based on sound reasoning. (some are) and so, as mentioned above, what do you want to do? Ride it? Show it? (curio value) How much free time and $$$ do you have to prove or disprove the design as viable?
 
that steering neck just looks hung out there. Not a lot of real good bracing. And the bracing that is there won't help much for flex under heaving braking. plus as I recall those down tubes are not the the thickest so they aren't going to provide that much strength either. There are very few frame designs that dont have a fairly direct link from the neck back.
 
After too long, I'm finally in a time position to tackle this project again and have begun to disassemble the engine. A previous owner had converted the motor to a single carb with the intake manifold appearing that it could have been fabricated by the builder. This manifold is held on by 3 Allen screws. What is interesting is that in both the shop manual and the parts exploded view, 4 bolt holes are shown attaching the intake manifolds for dual carbs. Don't know if 3 was a production variation or if the builder filled the inner pair and then drilled and tapped a single center bolt.

The Allen bolts retaining the manifold easily came out, though the center one required that I cut down an Allen wrench, ruining 3 hack saw blades in the process.
Reviving a Norton
IMG_0812 by jfm_K75, on Flickr

The bolts and nuts securing the cylinder head came off easy enough, except #1 in the tightening sequence. In the picture below, the bolt head on the right.

Reviving a Norton
IMG_0813 by jfm_K75, on Flickr

Most of the fasteners showed evidence that lock-tight or similar was used on assembly and I suspect for #1 that this is also the case. Due to the location it is difficult to get heat on to the position in the cylinder where the bolt is threaded. I'm more afraid of stripping the bolt head than breaking it off. I'll try it again tomorrow with more heat and a hand impact tool, but I need to get the proper size impact socket.

Jim
 
rvich said:
Is this likely to be the only Commando you will ever own? You will put a lot of work into getting that bike going and a fair bit of money. Most of us will not be able to give you any advice on problems you encounter because of the custom one-off build. It means you will be solving any geometry problems yourself and are basically designing a motorcycle from the ground up. If it doesn't handle well when finished, the frame will be suspect, despite the fact that it might be something else. If it were me, I would find a straight frame, build a stock or reasonably close to stock bike and I would keep that frame as a collectible. Just my two cents. But I think it makes even more sense to get a stock frame if you think you might want to one day sell the results of your efforts.

There are a few members on here who have a lot of experience with Seeley frames and Featherbed frames. If nothing else, get the frame stripped down. Take a lot of photos and measurements and then get some advice from people who know frames. Maybe put the frame in the back of the truck and go visit NYC Norton.

You gotta wonder why this bike sat for so many years if it was a good idea to start with.

Russ

Good points Russ. I'm a long way from deciding what to do about the frame and will cross that bridge when I come to it. Rebuilding the motor is the first priority. The worst thing that happens is that get together and it handles poorly and I need to find a frame. Most likely I'll replace items like bearing, bushings and fork seals, but not paint the bike, then see how it handles. If like crap then I can find a frame and the parts over.

Someone asked if I can find out who the modifying owner was? I do know and plan to seek him out to ask about his experience with the bike.

Jim
The question
 
Having seen first-hand what the atmosphere at N-V was like, having a "better idea" wouldn't be unusual. There was a lot of antagonism between the manufacturing folks at Plumstead and the engineering/design group in Wolverhampton. There was also a rapidly dwindling financial base. I was very surprised that the company lasted long enough to get to the electric start 850. I expected it to have died by about 1972.

I wasn't keeping track of N-V very much by then, as I'd just gone through the big Boeing layoff period. They reduced from 103,000 employees in 1968 (when I started there) to 36,000 in mid 1971. I was laid off at Easter of 1971, in the next-to-last block.
 
Reviving a Norton


Despite having sat for nearly 30 years the right cylinder and combustion chamber look OK, but the left...

Reviving a Norton


Note the spark plug tip, the plug was frozen to the aluminum. Probably not the first time that has happened

Took the head by a friend's shop to get a quick evaluation of the condition of the head and if it is salvageable and he felt it would be, but was interested in the condition of the valve seats.

Removed the valve caps and rocker covers in preparation for removing the valve train. These areas appeared clean and oiled.

Reviving a Norton
 
Keith1069 said:
Head fin extensions look quite well done, was wondering why it looked different. That IS a lot of work. Was the builder trying to replicate aspects of the Featherbed frames?

That is what I'm thinking.

Slick
 
Dog T:

Thre were lots of differing opinions at N-V i n that time frame and it wasn't always that the best ideas survived. Management of all the competing ideas wasn't a strong suit.

The problem of fatigue failure of the top frame tube became painfully obvious during the 1967 scrambles season with what became the AJS Stormer. At one meeting, BSA's pro, Dave Bickers asked for a test ride. After a few laps he came back quite enthusiastic about the bike's handling. When we got the bikes back to the factory, we discovered that the one Dave had ridden had suffered a complete through fracture of the top tube. The fuel tank was the only thing holding the frame together.

I suggested splitting the top tube along its horizontal center-line and inserting a triangular gusset that made the top tube connect with the extremities of the headstock and taper to circular at the seat. It was adopted and solved the problem.
 
I didn't see this when originally posted.

In looking at the pictures this is very high quality fabrication. It actually looks like it could be a factory modified test bike.

The structure looks sound to me. There is an upper tube that is bolted in to add strength to the steering head. The down tubes are cross braced. I would not be afraid to restore this frame and use it.

If it were my bike I would be doing a search for info and try to follow the trail back to the origin.
 
Sleeping Dog said:
Removed the valve caps and rocker covers in preparation for removing the valve train. These areas appeared clean and oiled.

Reviving a Norton

Rather interesting looking rockers you have. Makes you wonder whet else is hiding in there.
 
There has been some discussion regarding the adequacy of the frame and whether it is strong enough not to flex like a rubber band. Additionally sharp eyed readers have noticed the extensions of the cylinder head fins and the rocker arm assembly.

The original owner and builder of the bike is Harry Eddy of HeliBars. Recently I reached out to him to ask about the frame and anything else that he could remember and was willing to share. With regard to the frame, he said that the modifications were successful and the bike was stiffer than with the standard frame. He assured me that, unless the frame had been tweaked in an accident, it will perform well.

The engine is interesting. First it had been balanced and blueprinted, with the cylinders bored out to 906cc. They head had been ported and polished with larger valves installed actuated by a lightweight valve train including push rods and tappets. There is also a high lift cam shaft. Harry estimated that the motor was putting out approximately 90hp and 75 ft/lb of torque when he had it.

The fin extensions on the cylinder head are one thing on the bike that he considers a mistake, chalking it up to youthful exuberance and skill prevailing over good judgement. In the picture below you will notice a phenolic block between the top and second fin on the right side of the head. There is a hairline crack starting along the weld that the block supports.

Reviving a Norton


Harry suggested binning the head if I planned on converting to dual carbs. Given that I like the idea of a single carb and the long intake manifold run (torque, torque, torque), his thought was to remove the fin extensions. I haven't made a final decision on this and there are several questions about this cylinder head that need to be answered. One spark plug was frozen in and removing it stripped some threads from the aluminum and I need to determine what it will take to repair that and I need to see what the condition is of the valve seats, particularly on the left side. Also not that the intake side of the head has been modified with 3 bolts holding the intake, rather than 4.

And by the way, I'll be looking for a good condition cylinder if there is one around.

Jim
 
Jim,

Are you saying you want to replace the head or the cylinders...with all those mods to the engine can you just change things?

I think you may be opening this engine up soon to figure out what you have :D

It's really great that you tracked down the builder. He may be of help as you go forward.

Dennis
 
dennisgb said:
Jim,

Are you saying you want to replace the head or the cylinders...with all those mods to the engine can you just change things?

I think you may be opening this engine up soon to figure out what you have :D

It's really great that you tracked down the builder. He may be of help as you go forward.

Dennis

Hi Dennis,

I am in the process of dismantling the engine. When I removed the head this is what I found in the left cylinder

Reviving a Norton


Lots of rust and pitting since water was able to get inside. Due to the previous over bore, I question whether there is sufficient metal in the cylinder walls to bore them out enough to remove the pitting and get to clean metal. Then there is question of availability of pistons.

With regard to the cylinder head, my preference would be to remove the fin extensions, repair the threads of the spark plug hole, install new valve seats and clean the intake and exhaust ports and move on. This all depends on what the machinist opinion is. It maybe simpler and cheaper to start with a different head and bring it to the specs of the current one when new. All to be determined.

Dennis, just noticed that you live in MN, when I lived in Minneapolis I regularly stopped at the Norton Club gathering at Dulano's on Lake St.

Jim
 
Sleeping Dog said:
I am in the process of dismantling the engine. When I removed the head this is what I found in the left cylinder

That might be a candidate for being sleeved - especially if the metal down lower is not too far gone.
Allows stock type pistons and sizes, and keeps some strength in it all.
As long as the rust hasn't gone too deep over too much of it.
 
Sleeping Dog said:
Dennis, just noticed that you live in MN, when I lived in Minneapolis I regularly stopped at the Norton Club gathering at Dulano's on Lake St.

Jim

Haven't done that yet...I'm relatively new to getting back into Norton's (had one back in the 70's) and my bike is still a work in process.

Are you going to see if you can free that cylinder up? You'd be surprised if you do, maybe it's not as bad as you think. Likely will need a rebore, but worth a shot IMO.

Edit: Sorry forgot it was bored to over 900cc...boring probably not possible. I'd still try to break it loose to have a look see.

Dennis
 
Sleeping Dog said:
............The engine is interesting. ...... I haven't made a final decision on this and there are several questions about this cylinder head that need to be answered. One spark plug was frozen in and removing it stripped some threads from the aluminum and I need to determine what it will take to repair that and I need to see what the condition is of the valve seats, particularly on the left side. Also not that the intake side of the head has been modified with 3 bolts holding the intake, rather than 4........Jim
I agree that that is an interesting engine that you have there. Have you considered sending it to Jim Comstock aka comnoz on this forum and owner of the norton machine shop located in Pueblo, Co. He can repair the spark plug hole threads and repair the crack in the fin and fix anything else that might be wrong with the head. Just a thought. Cj
 
Rohan wrote
That might be a candidate for being sleeved - especially if the metal down lower is not too far gone.
Allows stock type pistons and sizes, and keeps some strength in it all.
As long as the rust hasn't gone too deep over too much of it.

Sleeving the cylinder is something that I haven't considered, but an option that I'll check into.

cjandme wrote
I agree that that is an interesting engine that you have there. Have you considered sending it to Jim Comstock aka comnoz on this forum and owner of the norton machine shop located in Pueblo, Co. He can repair the spark plug hole threads and repair the crack in the fin and fix anything else that might be wrong with the head. Just a thought. Cj

I'm aware of Jim Comstock by reputation for doing quality work, but there are resources closer to home that I plan to utilize.

If my wife doesn't find something for me to do... The plan is to free the cylinder and remove it along with the pistons. Take the valves and valve train out and get the lot evaluated.

Jim
 
I would chuck it all into the recycle trash and instead pull out the checquebook. Just the way I would approach it after those horrid viewings. Enjoy.
 
As those of you who have read earlier posts know, the left cylinder has significant rust. I've removed all the retaining nuts (5) and bolts (4). Rapped the cylinder pretty good with a mallet cushioned by a block of wood and know movement. While the cylinder may simply be stuck to the crankcase, I suspect that one piston is rusted to the cylinder wall.

Any suggestions on freeing this?

A local Norton club member suggested filling the cylinder with Evapo-Rust (http://www.evapo-rust.com/), but I have some concern about this draining into the crankcase. If there is any chance that the bottom end is salvageable without a rebuild, I'd like to preserve it. Thoughts?

Jim
 
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