Starting cafe racer restoration Commando 850 MK3 from Spain

On this as on several other parts and kits like the carburetors I will better follow your expert advice. On classic bikes projects it is always quite tough to estimate a budget because it always goes up quite more than expected!
 
Definitely good value in doing the job right the first time on these machines to keep them reliable
 
Today I tested a small Lithium battery with a CCA 300A that I normally use on my Ducatis 1100cc. I wanted to test how the Commando starter motor behave and also test the battery power.
Since the bike has virtually not electric wiring I just directly connected the battery to the frame and then to the starter input screw, my surprise came when the starter just freely spins but it looks like not being engaged to the engine. I exchanged positive and negative leads only to get the same result: free spinning but not moving the crankshaft and engine at all.
I then removed the two small screws that apparently join the starter to the engine and I tried to remove the starter by pull it but it seems to be locked... or there must be another screws or parts I need to undo first?
Can you give some clue about the starter motor behavior before I start opening the primary transmission cover to find out?
 
Do you mean this flat one?
 

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Do you mean this flat one?

Yes, the slot head primary cover screw.

Can you give some clue about the starter motor behavior before I start opening the primary transmission cover to find out?

Probably a missing Edit: broken or flipped-over starter sprag, or the complete starter motor drive is missing.
 
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IIRC the idler gear spindle locates in the front of the starter too (item 4 in the diagram)
It's just a press fit but can be stubborn!!

 
Then I will open the primary cover to find out. I hope it will be some simple issue that makes the starter not to connect with its gear.
 
Today I unsuccessfully tried to remove the primary transmission cover along two hours. The previous owner applied gasket seal that is completely stuck. I tried pulling from the gear change lever, hammering protecting the cover with a pieze of wood, heating up with a heat gun.. no way.
The cover is blocked and sticked.
Desperate I even used a steel ratchet tie down to hold the bike frame from one side and pull with another ratchet strap from the other but even so I did no move the cover. I was afraid of getting hurt or cause a disaster and I did not applied full pull with the ratchet.

Any suggestions about how to remove the stubborn cover?
 

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Thank you for the link, in fact I followed it and that is why I have been pulling from the gear change lever with confidence but with no success.
The only thing from the post I need to try is getting single edge razor blade to cut the gasket carefully.
 
Thank you for the link, in fact I followed it and that is why I have been pulling from the gear change lever with confidence but with no success.
The only thing from the post I need to try is getting single edge razor blade to cut the gasket carefully.
The single edge razor blade although tedious will work.
 
Today I unsuccessfully tried to remove the primary transmission cover along two hours. The previous owner applied gasket seal that is completely stuck. I tried pulling from the gear change lever, hammering protecting the cover with a pieze of wood, heating up with a heat gun.. no way.
The cover is blocked and sticked.
Desperate I even used a steel ratchet tie down to hold the bike frame from one side and pull with another ratchet strap from the other but even so I did no move the cover. I was afraid of getting hurt or cause a disaster and I did not applied full pull with the ratchet.

Any suggestions about how to remove the stubborn cover?
Is your clutch still connected and working?
If so try screwing the inspection cover back in with a packer behind against the clutch adjuster
Then operate the clutch and see if that will push it off
 
Is your clutch still connected and working?
If so try screwing the inspection cover back in with a packer behind against the clutch adjuster
Then operate the clutch and see if that will push it off
A fine bladed craft knife would have sorted it i would have thought
 
As suggested using a shave blade and some patient I cut the gasket all around and the cover came off easily. The blade was very thin so I did not cause noticeable damage to the case or cover.
Without the blade it would have been almost impossible to take the cover off.
Here the pictures of how the gears are. Next will be finding out whatĀ“s wrong with the starter E-starter gear.
 
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