1979 R65 Rear Wheel Issue

[Rick]

I am in the process of refurbishing a 1979 R65 and learning along the way.  I am hoping someone can help with an issue that came up yesterday that has me puzzled. I recently adjusted valve clearances and used the rear wheel to turn the engine to TDC for the valve adjustments.  The bike was on the center stand on a block of wood to get the rear wheel off the ground. The wheel turned as it should when bumping the engine to the timing marks with the transmission in gear.  Once the valve adjustments were done and I got it buttoned back up I started the bike to see how it ran.  Since the rear wheel was off the ground I decided to keep it running and run it through the gears since I haven't had a chance to ride it yet to check things out.  It seemed to shift OK and took it back down to neutral and shut it off.  I took the bike off of the center stand and blocks to get both wheels back on the ground and it was then that I noticed that I couldn't move the bike.  It was in neutral with the engine off.  Put it back on the center stand with blocks to get the rear wheel off the ground again and tried to turn the rear wheel and couldn't budge it.  The neutral light is on and I am fairly certain it truly is in neutral but the rear wheel won't budge.  I started the engine, put it in first gear and released the clutch and the rear wheel turns but when shut off again and back in neutral the wheel is still stuck. I couldn't find anything by searching he internet that might even give me a clue as to what happened or what might be the issue so I am hoping someone may have ideas or had run across this before.  Clutch?  Transmission?  or
Thanks!

[montmil]

First question I have is: After bringing the bike to TDC and setting valve clearances, did you then rotate the engine and bring up TDC to adjust the opposite cylinder?

[Rick]

Yes I did rotate 360 to adjust the opposite side valves.  

[Bob_Roller]

With the rear wheel clear of the floor, with the engine running and the neutral light illuminated, does the rear wheel continue to rotate ??

[Rick]

No Bob, it does not continue to rotate.  

[montmil]

The Airhead gearboxes are factory-supplied with several false neutrals. Whenever I get lazy with my shifting, I can find one.

With the engine off, try shifting through the gears and back to neutral. You may have to roll the bike fore and aft a bit. Report back.

[Barry]

So there is no drive when the gearbox is in neutral but the wheel is still stuck.

That means the gearbox is selecting neutral OK. Which leaves the drive shaft, rear drive/wheel/brake assembly.

The rear brake isn't stuck on is it ?

Agave,
I realise this isn't any help at all this point but I only tried bumping the engine over once using the rear wheel and decided the shock loading was much too violent on the whole transmission system. I know lots of people use the rear wheel but I now always use an Allen key in the rotor bolt with the plugs out to make life easier. You did have the plugs out ?

[Rick]

Thanks for the responses so far guys.  
Montmil,  I don't know if I can rock the bike back and forth enough to get it to shift through all gears because of the locked up rear wheel but will try either tonight or tomorrow and report back.
Barry, I was wondering about brake being stuck too.  I did have the rear wheel off recently to put a new tire on but when put back on it turned freely and also turned OK during bumping.  Maybe the brakes stuck for some reason when I ran the bike through gears with the wheel off the ground.  I will check the brakes too.
Regarding bumping I have read good and bad about both ways of turning the engine over.  Point taken though about the possible transmission stress due to bumping the rear wheel.  The wheel was off the ground already when I did the valves so I just used the whel bump method rathr than take the front cover off.  Yes the plugs were out also.
To be continued.  Thanks again!

[montmil]

Sounding more and more as if the rear brake is stuck "on".

First, try backing off the adjuster on the aft end of the brake rod. If the brake is indeed stuck, you will not be able to get the rear wheel off for an inspection. Maybe the brake cam has gone over-center?

[Rick]

I was starting to think brakes too Monte.  That was the first thing I was going to do.... see if I can get the wheel off.  That will tell me if the brakes are stuck.  If thats the case, then another problem... how DO I get the wheel off?  

[montmil]

I was starting to think brakes too Monte.  That was the first thing I was going to do.... see if I can get the wheel off.  That will tell me if the brakes are stuck.  If thats the case, then another problem... how DO I get the wheel off?  

If the brakes are truly locked onto the drum, ya ain't goona get that wheel off until they -brakes- return to their original relaxed position. After backing off the adjuster nut, check the brake arm for any movement. Perhaps a gentle plastic mallet tap in the opposite direction of the rod's pull might encourage a release.

It's going to be something simple. Brake cam over-center. Maybe a tad embarrassing, but... simple. Once free wheeling, pull the rear wheel. You're baby just may need some new shoes.

[Bob_Roller]

Checking the rear brake seems to be the next thing to check, as Monte has said .

But this is really an odd situation that this happened all of a sudden .

Does the rear brake pedal move at all

[Rick]

The rear brake pedal does move as if normally operating Bob. It is worth checking the brakes first to rule that in or out but it could be a false neutral as Monte noted earlier.  If it is a false neutral though, shouldn't the rear wheel turn if the clutch is engaged no matter what? The wheel doesn't turn even with the clutch engaged with the engine not running.  Very puzzling.  
I appreciate the suggestions for things to take a look at.
    

[Bob_Roller]

Does the rear wheel move at all when you have it clear of the floor and the transmission neutral indicator illuminated ??

You should have some ' free play' in the drive train, be able to move the wheel by hand maybe an inch or so in rotation, even if the tranmission is in gear .

If it is locked solid, the rear brake is looking suspect .

[nhmaf]

I am also with the "brakes are on or something has slipped in the rear hub to cause wheel to be locked up" camp.

I use the rear wheel to turn the engine for setting valves, etc. all the time.   The "shock load" of rolling the throttle on and off while running on the road will transmit much more of a shock load through the drive train and gearbox than what any human can do with their arms on a sitting still bike without knocking it off the centerstand entirely.