Starting cafe racer restoration Commando 850 MK3 from Spain

If someone forgot to put the dowel #19 (part-no: 06.7621) back on reassembly what's the worst that can happen. Asking for a friend.
 
I suggest you need twin discs on the front. A Commando is too heavy for one, if you really get it going. The rear suspension is probably more important than the front. When control is lost by the rear suspension, to the rider it often feels as though the problem is with the front. The rear suspension also affects the way the bike steers as you accelerate out of corners. When the rear squats when you accelerate, a neutral handling bike will usually tend to self-steer in the direction you need to go.
 
Hello,

This is going to be my third restoration-cafe racer-project and my first British classic bike so I am probably need your help!
Due to work and family reasons I use to spend one to two years to finish my projects but I will certainly finish and the result with this great motorbike will certainly pay off.
I bought the bike from a guys than document me he order in 2006 the following professional work from an experienced mechanic in Granada (South Spain) made in 2006: polished rims, hubs, fork, triple trees, polished and painted frame, rectified and reapair heads and cylinders,.

Since then the bike has being stored and the engine has not run so supposedly it should have 0 kms.
Find here some picture of how the bike is
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Great looking classic! I have only had my Norton Cafe racer 850 1973 2 months now.
 
My plan is to use the same Lithium battery I used on two of my 1000cc Ducatis it is quite small and produce CCA 300A, Capacity 5Ah. I hope it will be powerful enough to feed the starter motor.
I had lithium battery on my last bike BSA A65L great battery light and don't deteriorate from lake of use!
 
Here I am again. After lots of work (I counted 370 hours) and many different issues solved with lots of patiente and some help from some friend Norton passionates in Spain I finally make my Commando run.
Starting cafe racer restoration Commando 850 MK3 from Spain




The bike starts af second kick, keeps a perfect idle and runs acceptably well but leaks lots of oil apparently around the head gasket area and what is driving mi nuts is the fact that does not revs beyond 4500 to 5000 rpm.
Fron idle to 4000 rpms runs smoothly bur t beyond there vibrates more and more and does not want to rev.
After replacing the head gasket, check the correct Boyer timing, check the choke and new carbs, check fuel lines and tank cap I removed the timing cover to discover the timing pinion was mounted upside down!! The intermediate sprocket seems to be ten rollers apart from the camshaft sprocket but this is rotated 180º.
This was done by the previous owner but I do not understand how the engine can start up and run so smooth if the camshaft is set rotated 180º to the crankshaft.
Can you give a clue? Should I remove the camshaft sprocket and set it properly?
Starting cafe racer restoration Commando 850 MK3 from Spain
 
After replacing the head gasket, check the correct Boyer timing, check the choke and new carbs, check fuel lines and tank cap I removed the timing cover to discover the timing pinion was mounted upside down!! The intermediate sprocket seems to be ten rollers apart from the camshaft sprocket but this is rotated 180º.
This was done by the previous owner but I do not understand how the engine can start up and run so smooth if the camshaft is set rotated 180º to the crankshaft.
Can you give a clue? Should I remove the camshaft sprocket and set it properly?
Can't tell from the picture - were the crank pinon gear and intermediate gear timing marks aligned when you took the picture? Are your white marks aligned with the dots in the intermediate and camshaft sprocket? Do you know what cam is in the engine? Have you checked that the ignition timing marks are correct?

If you're sure the components (crank, cam, intermediate gear/sprocket, cam sprocket) are correct, if yes, I would re-do the cam timing.

I don't know older Nortons - others may know about other parts but the crank is different for an Atlas and Commando - I know that the ignition timing marks are very different - don't know if it affects cam timing.
 
The crank pinon gear and intermediate gear timing marks were aligned when I took the picture and they are correct. The crank pinion two marks are pointing down corresponding properly with the crankshaft and the intermediate pinion mark points at 12 o`clock.
Yes, the white marks are aligned with the dots in the intermediate and camshaft sprocket.
I do not know what cam is in the engine.
Yes I checked that the ignition timing marks are correct.

The fact is that I rebuilt the complete motorcycle and the only two parts I did not rebuild because they where rebuilt by the previous owner are the crankshaft, the barrel + pistons (which had good compression and look perfectly rebuilded), the head (which was perfectly cleaned inside) and the timing gears and chain. My surprise is to discover the camshaft sprocket to be assembled upside down!
May this produce engine vibration over 4000rpm and may this refrain the engine to rev over 4500rpm?
 
The crank pinon gear and intermediate gear timing marks were aligned when I took the picture and they are correct. The crank pinion two marks are pointing down corresponding properly with the crankshaft and the intermediate pinion mark points at 12 o`clock.
Yes, the white marks are aligned with the dots in the intermediate and camshaft sprocket.
I do not know what cam is in the engine.
Yes I checked that the ignition timing marks are correct.

The fact is that I rebuilt the complete motorcycle and the only two parts I did not rebuild because they where rebuilt by the previous owner are the crankshaft, the barrel + pistons (which had good compression and look perfectly rebuilded), the head (which was perfectly cleaned inside) and the timing gears and chain. My surprise is to discover the camshaft sprocket to be assembled upside down!
May this produce engine vibration over 4000rpm and may this refrain the engine to rev over 4500rpm?
Keep in mind that it takes two revolutions of the crank for the marks to all align.

You should have the crank pinon and intermediate gear marks point at each other - crank at 12 o'clock and intermediate at 6 o'clock. That will put the intermediate sprocket mark and cam sprocket mark at 12 o'clock.

If that is not the case, I would definitely correct it! If it's like you say, then the cam is 90 degrees out from where it should be in relation to the crank.
 
If it's like you say, then the cam is 90 degrees out from where it should be in relation to the crank.

The engine is 180 degrees out, as the picture appears to show (the punch mark on the cam sprocket is where the paint mark is). If it was 90 degrees out, it wouldn't run.
 
The engine is 180 degrees out, as the picture appears to show (the punch mark on the cam sprocket is where the paint mark is). If it was 90 degrees out, it wouldn't run.
The cam is 180 degrees out from "correct". That makes it 90 degrees out in relation to the crankshaft which is what I said - I suppose if you think of it in reverse it is 360 degrees out from the crank. I have no idea if it should run which is why I asked so many questions in my previous post. It could be a weird cam, someone cut a new keyway in the cam, a wrong part, or something else - re-doing the timing will probably answer some of that and if just wrong, then it will run right most likely.

Do you know why the Atlas and Commando cam sprockets have different part numbers. Also, the intermediate gear/sprocket for the Atlas and Commando seem to be different parts. I have no idea if either of those for an Atlas will fit a Commando and if they would cause this issue.
 
I have no idea if it should run

It is running.

Do you know why the Atlas and Commando cam sprockets have different part numbers.

Yes, they have different numbers after the points cam was introduced so the early (twin chain) Commando cam sprocket is the same (06.7775)
Also, the intermediate gear/sprocket for the Atlas and Commando seem to be different parts.
Yes as there's no ignition timing chain sprocket on the later intermediate gear, plus the Mk3 intermediate gear is different again (thinner).

 
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The cam is 180 degrees out from "correct". That makes it 90 degrees out in relation to the crankshaft which is what I said - I suppose if you think of it in reverse it is 360 degrees out from the crank. I have no idea if it should run which is why I asked so many questions in my previous post. It could be a weird cam, someone cut a new keyway in the cam, a wrong part, or something else - re-doing the timing will probably answer some of that and if just wrong, then it will run right most likely.

Do you know why the Atlas and Commando cam sprockets have different part numbers. Also, the intermediate gear/sprocket for the Atlas and Commando seem to be different parts. I have no idea if either of those for an Atlas will fit a Commando and if they would cause this issue.
When the points were moved to the timing cover the cam sprocket and intermediate sprocket where altered.
 


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