Nut that covers the front sprocket moves

[pete]

Gabriel,

when you tighten the nut use a long handle for more leverage, or better still..a proper torque wrench. Also, (in 1st gear with the chain on ) have someone standing on the rear brake pedal. this will stop you from simply turning over the motor as you try to tighten it.

Definitely do this! After I discovered mine was like that, I tightened it up as best I could, but I was by myself (noone to stand on the brake), had no torque wrench, and the only spanner that would fit was a shifter, so as you can imagine it wasn't long before it was loose again... once I get it all back together this time, I won't be making that mistake again!