Engine will not turn

[mad-dawg]

Was checking valve clearances today (thanks Steptoe for sticky)
There is always a But!!
Removed the covers and plugs put bike in gear, screwdriver down plug hole tried turning back wheel and it hardly moves. Tried harder and double checked the plugs were out (yes). Tried all 5 gears (R1100GS) same result, wheel turns a 1-2 inches then stops. with a lot of force there is a clunk from gearbox but will not turn engine over.
in the end I removed alternator cover and used pulley bolt (out of gear) but am puzzled why engine will not turn over with back wheel.
Bike rides okay and the wheel must turn the engine on overrun?
I tried rotating forwards and backwards and damn near lifted the bike of the ground. Is this a sign of impending doom or am I being very dull and weak and missing something?

Also left fork slider rotates fairly easily, checked and tightened nut to correct torque but still rotates. This probably has no effect on the bike but would like a view on whether a drop of loctite is in order?
Thank you in advance for your observations and comments.

 

[ghiribizzo]

More application of elbow to rear wheel...

 

[Timolgra]

Removed the covers and plugs put bike in gear, screwdriver down plug hole tried turning back wheel and it hardly moves.

Careful!....give the wheel a 'bump' and it'll turn the engine.
Remove the cam covers and turn the engine until the marks on the sprocket are horizontal whilst on the right stroke.

 

[warmshed]

Try a high gear not 1st or second, 6th will be best. Watch you dont "Jam" the screwdriver.

 

[street_moto]

I find it easier to turn the engine using a 16mm socket and wrench on the bottom pulley on the front of the engine under the alternator cover.

 

[DrFarkoff]

Tie the centre stand to the front wheel before you push twist pull harder

 

[MattW]

Tie the centre stand to the front wheel before you push twist pull harder

What Jaythro sez - I ever so nearly pushed mine off its stand doing just this

I have the bike in fifth gear, sit behind the back wheel and pull the bottom of the tyre while looking forward at my screwdriver poking out of the plug hole. Sitting like this, you can brace your foot against the centre stand. I usually don't bother taking the other plug out - just ease it over compression. Obviously make sure your screwdriver (or other piston touching prodder (I actually use a length of 8mm ally tube) is poking straight out of the plug hole and isn't skewed so it can jam.

Always works for me

 

[Steptoe]

Eat some spinach.

The rotating fork slider isn't a problem.

 

[Naim]

I find it easier to turn the engine using a 16mm socket and wrench on the bottom pulley on the front of the engine under the alternator cover.

+1 Why arse about with the back wheel?

 

[MattW]

+1 Why arse about with the back wheel?

Because if you've got certain engine bars fitted (like the ones I used to have), you have to 'arse about' removing them (and sometimes the tank / bashplate) in order to remove the plastic front cover and get to the crankshaft pulley...

Even now I don't have engine bars fitted, I still use the wheel - plug out, bike in top gear, screwdriver down plug hole, turn back wheel - minimal unnecessary dismantling - doesn't get much simpler

 

[Steptoe]

+1 Why arse about with the back wheel?

Because it's a lot easier than removing the front cover and cranking it using a socket and bar.

If you go a bit too far using the socket and bar you then have to wind it another 360 degrees, because you can undo the alternator pulley nut if you want to knock it back just a touch...
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