Okay, this might be a dumb question to some, but when is a motorcycle engine considered "unrepairable"? The reason I ask is, as I posted in the BSA section, I can get an A65 lightning for cheap cheap. It's in very rough shape and the engine is seized. Now the whole reason for wanting to buy this is to try my hand and get some practice at rebuilding a motor. Some websites I've researched say a seized motor can often times be easily rebuilt, others say that they're all a waste of time and belong in a junk yard. So, why the difference? I'm guessing the way the engine seized has a lot to do with it too? Sorry if this is in the wrong section, as I know it's not Norton specific.
When is a motor considered unrepairable?
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Fast Eddie
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msh5337 said:
I would imagine that web sites that say seized engines are junk and not worth working on are web sites for modern, small, possibly dirt bike motors that are 10-a-penny, yet expensive to rebuild.
The answer to your question is pure economics, when the cost of rebuilding an engine is a lot more than buying a new one, then it ain't worth it.
So, unless you know of a hoard of new A65 motors... yours is obviously worth rebuilding!
Old Brit motors 'benefit' from thick, heavy castings etc, making them highly rebuildable as a rule.
lazyeye6
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Uh...... most motors are repairable.. The question is, how much will it cost. You could easily sink a couple of thousand or more into a motor only to find that the rest of the
bike is also beat up and needing extensive repairs and that all fixed up it's sales value is much less than the money invested, not even counting your time. Anything less than a Stunning above average Lightning doesn't sell for the kind of money a Norton or Triumph would. Ask me how I know. If you just want the experience of rebuilding a motor, think about finding
A Triumph or BSA 250 with no illusions that anyone will actually want it when it's done.
bike is also beat up and needing extensive repairs and that all fixed up it's sales value is much less than the money invested, not even counting your time. Anything less than a Stunning above average Lightning doesn't sell for the kind of money a Norton or Triumph would. Ask me how I know. If you just want the experience of rebuilding a motor, think about finding
A Triumph or BSA 250 with no illusions that anyone will actually want it when it's done.
If it's seized, something is stopping it turning.
Usually piston/rings rusted to bore (can be freed with lubricants or pressure and then reborn and new piston kit
OR
Big end collapsed - can be replaced with new crankpin and bearing.
Or it could be a locked up gearbox, jammed timing gear all of which are repairable/replaceable. As long as you buy it very cheaply and do or sub contract work you should be alright.
Trouble is, you can't do much about the aesthetics of an A65 motor.
Usually piston/rings rusted to bore (can be freed with lubricants or pressure and then reborn and new piston kit
OR
Big end collapsed - can be replaced with new crankpin and bearing.
Or it could be a locked up gearbox, jammed timing gear all of which are repairable/replaceable. As long as you buy it very cheaply and do or sub contract work you should be alright.
Trouble is, you can't do much about the aesthetics of an A65 motor.
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Take the plugs out and have a look at them. If they are white inside all the way to the bottom or have beads of aluminium on them or rust, you will know why the motor seized - unless it has a rod poking out the bottom, then you don't need to look at the plugs. A simple seizure is usually an easy fix. Big internal damage can be much more expensive. What ever you do, do most of the work yourself and farm out any machining. It is NOT rocket science. Only a problem the first time you do it. If you get into trouble - ask for help.
o0norton0o
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msh5337 said:
... when you run out of money... :lol:
MHS, The good thing about classic British bikes is that they are designed to be rebuilt, so there are 3 or 4 sizes of oversize pistons allowing several opportunities for a re-bore and then with some bikes you can fit cylinder liners to bring them back to standard again, 3 different sizes of undersize crank bearings so that the crank can be ground several times, oversize valves, oversize valve guides etc., etc. all of this means that the motor would have to be in very bad shape for it to be unsalvageable. Furthermore there are many new and 2nd hand parts available particularly for BSA, Norton or Triumphs. As others have pointed out the only barrier is cost but if your goal is to learn something about classic motorcycle engineering and you get the bike for little money then you can't go wrong. I would highly recommend that you obtain a copy of 'Vintage British Street Bikes' which is part of the Clymer Collection Series of publications.
Be patient when you disassemble anything, if it is hard to take apart use lots of penetrating fluid, look for hidden fasteners (Nortons have one cylinder head bolt that people often miss and consequently they break fins trying to pry the head off!) try a bit of heat and ask lots of questions on sites like this. Good luck and welcome to a life of joy and frustration in equal measure.
Be patient when you disassemble anything, if it is hard to take apart use lots of penetrating fluid, look for hidden fasteners (Nortons have one cylinder head bolt that people often miss and consequently they break fins trying to pry the head off!) try a bit of heat and ask lots of questions on sites like this. Good luck and welcome to a life of joy and frustration in equal measure.
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Money. All rusty old thingys can be fixed or even improved. :shock:
msh5337 said:
This is the perfect bike for that. You won't have a lot invested. You don't have to spend a ton of money if it is all junk. And you will learn a lot taking simply it apart and putting it back together. The pitfall is that a very nice Commando that would sell in the $7,000-$10,000 range that can easily have much more than $10,000 spent on rebuilding it. I quit counting after $7,000 and my bike is not that nice. But I love it. And I learned a lot by taking an incomplete basketcase back to a reliable, fun bike to ride.
Greg
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A couple of points.
I'm not sure a BSA A65 is the easiest engine to start learning how to do a rebuild on. If you've never tried a rebuild before, a cheap Japanese single cylinder might be more sensible.
If you do go ahead, there is one BSA model that has a trap for the unwary: The oil lines cross over when they leave the oil tank and enter the engine!!!! This has cost a lot of people a lot of money BUT I can't remember if it's on the A65 or a different model.
I'm not sure a BSA A65 is the easiest engine to start learning how to do a rebuild on. If you've never tried a rebuild before, a cheap Japanese single cylinder might be more sensible.
If you do go ahead, there is one BSA model that has a trap for the unwary: The oil lines cross over when they leave the oil tank and enter the engine!!!! This has cost a lot of people a lot of money BUT I can't remember if it's on the A65 or a different model.
o0norton0o said:
Well, it is a trick question....they are all repairable. It does however come down to a few things such as Money, but also time has to be factored in there too-(a big problem for me at the moment, and for the last 5 years), also motivation (you can run out of motivation- then none of it matters). having said all that, I say "Go For It"
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Once I picked up a BSA A65 that was said (by the seller) that the engine had seized. All that was wrong was kickstart gear was jammed, as they are prone to do. Another time a friend was sure he seized a TR6. Rather than start tearing it down, I suggesting checking the primary first. Broken primary chain, that was jamming things up. You never know until you investigate.
trident sam
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pommie john said:
The oil lines cross over on the B44.
No experience of A65 motors.
sam
Okay, thanks for the help everyone! I think I'm going to try it. I'm by no means going into it with the intention of flipping it to make some money. It's just going to be a learning experience for me. That being the case, I don't mind if it takes a few years and couple thousand dollars more than the bike is actually worth. All I want is, by the end of the project, to have another vintage Brit able to get me from point A to point B.
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msh5337 said:
here is my first bike, everything was done by myself, Engine, box, bodywork, lacing wheels etc etc
from the day i got it in the shed
to just requiring the paperwork sorting
i didn't spend an awful lot but my time was free. it was an interesting learning curve but well worth the effort
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trident sam said:
Yes, on the A65 also. Rebuilding an A65 uses the same skills as rebuilding any other old Brit WITH THE EXCEPTION OF the timing side crank bushing. A person who is perfectly competent at building a Sportster or small block Chevy or Triumph 650 will bugger up an A65 unless they understand how to set up the lower end, including line boring the bushing on an accurate machine, and shimming the crankshaft end play ...
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