Hi just seeing if anybody can tell me what the tyre and sprocket sizes should be on a Ossa 250 Verde 1979 please. Also am I rite in thinking that the chain tensioner bolts onto the chain guard.

Thanks, Martin

Rear 42 teeth, front 11 teeth.  Tyres are normal trials tyres,  4.00 x18" rear,  2.75 x 21" front

Chain tensioner is fixed to the brake pedal pivot spindle, not fixed to the swingarm / chain guard. If yours does someone has modified it

This is what the tensioner should look like

 

http://www.ebay.co.uk/itm/OSSA-MICK-ANDREWS-CHAIN-TENSIONER-OSSA-MAR-OSSA-EXPLORER-NEW-CHAIN-TENSIONER-/381111480886?hash=item58bc03b236:g:IoMAAOSwyZ5UqCc8

Cheers for that I will get some ordered this week.  Had a look at the tensioner and mine looks like it is a fixed one its just worn out a bit, it dose have little thin tube sticking out from the swinging arm that I'm not sure what its for. The little tube is properly welded into the frame and has a little hole drilled straight through.

Thanks, Martin