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Discussion Starter #1
I just buttoned up my CB360 engine rebuild and got the engine mounted back in the bike. I was meticulous with the rebuild. I took everything apart and cleaned with kerosene, reassembled with assembly lube, referred constantly to my Clymer and shop manuals, parts fiche diagrams as well as youtube videos from common motor. I'm finishing up brakes and new cables/as well as rewiring everything. Next on the list is tuning the engine (timing, clutch, valves, etc.)

I have a few concerns before I wrap everything up and hit that starter switch:
1. As I turn the engine with a wrench on the AC generator, I can only get 1-2 full revolutions before the engine stops turning and the bolt breaks loose. Is this normal?
2. Currently, I can't get the transmission to cycle through all the gears. The transmission shifted smoothly during the rebuild, before joining the bottom case. I realize there's a handful of clutch adjustments I can make to trouble shoot this.
3. What else should I check before I kick/hit the starter?

Thanks gang. Advice from the forums is always a great resource as well.
 

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1. Take the right side cover off, place a penny in the gears between the clutch and the crank shaft to hold things in place and properly torque the bolt. It should not come loose when you turn it.

2. Transmission will likely not cycle through all of the gears while the engine/transmission is stationary - not rotating. They need things to be turning to change gears. Put the bike up on center stand and rock the back wheel should at least be able to shift it a little bit. That is assuming you have the chain connected but you get my drift.

3. Knowing how 360s are, no matter how much assembly lube you used there is still a chance of cam failure. I would MAKE SURE the bath tubs on the top of the head under the cam are full of oil prior to starting the bike. Either make a funnel that can get to the tubs from the tappet inspection holes or pull the valve cover. I know this sounds like added work but they will eat a cam in a few short minutes if they have no oil.

I would also recommend pulling the plugs and working either the starter or the kick starter for a good 5 minutes so that you get oil moving around in the engine. Don't run the starter longer than 30 or so seconds at a time with a good minute or so break in between. Don't have to kick hard either just push through on the kick starter.

Good Luck! Sounds like you've done well otherwise!
 

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Discussion Starter #3
1. Take the right side cover off, place a penny in the gears between the clutch and the crank shaft to hold things in place and properly torque the bolt. It should not come loose when you turn it.
Thanks for the response!
I've got the bolt torqued to spec, but it seems like the engine is getting stuck somewhere in the revolutions. It only started happening after I got the valve covers back on.
Rebuild was due to cam chain breaking. I replaced the cam chain, tensioner system including arm in lower case, and valves which were damaged by the broken chain. I had the valve seats machined for the new valves and the cylinders honed. Replaced piston rings and all gaskets/oil seals. I'm nervous that the engine is getting stuck on something and if I crank it over with the kick, i'll just rip the cam chain apart and rebuild again. Thoughts?
 

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I take it you checked the valve positions at TDC to see if the piston is contacting any of the valves?
 

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Take it from a guy who just did this exact same project. When in doubt, take it apart all the way and check. I spent over a year on my rebuild but I did everything including new pistons, had the head and jugs decked and rebored oversize, new valves and guides.

Take the advice of others here too. Make SURE the oil baths are full and make sure you run the engine on the starter to get oil flowing. The cam is very unforgiving of oil starvation.

In my case I made the stupid mistake of not lock tighting the Cam gear bolts and had them come loose and destroy a timing chain. Like the other poster said use a penny to lock that gear next to the oil filter. Make sure those cam bolts are tight.

If you have the generator bolt to spec and its coming loose then I would pull it all apart and double check everything. Nothing sinks a heart faster than hearing metal on metal grinding and seize up after a fresh rebuild. Check that the rear slipper is in the correct place and that you correctly tension that timing chain.

Mistakes I made during my rebuild

Chipped a new ring with a shoddy ring compressor didn't realize till after starting had to rebore.
Didn't properly torque or lock cam bolts. Had to tear completely apart and rebuild with new chain and new bolts.
was missing a washer in the transmission form the prior owners "attempt" to fix. Would not change gears. Had to replace after total disassemble reassemble.

I swear I had that thing apart and back together like 15 times in a years time. I feel like I can do it in my sleep now!
 

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You need to remove cam/rocker cover and re-check cam timing and may need to lift head to check you didn't bend any valves (at least it's a lot easier on 360 than 350)
 

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Discussion Starter #7
So it was an issue with the cam timing lineup. Luckily, no bent pistons (especially since they're brand new) I missed one line in the manual regarding lining up the lines on the cam sprocket.
 

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Very rare for pistons to get damaged turning motor over, always the valves that bend. There should be enough clearance if you were only one tooth out but from your original description the valves were touching pistons hard enough to stop motor turning over. If you didn't try and force things you probably 'got away with it'
 
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