the funny thing was with it it has done it before and i just put it down to being in the wrong gear at the wrong time but took it out this morning down the m60 only doing 70ish and the some thing again. last night when i got back i went round it had a look at the plugs,choke,carbs,plug caps,ht leads,wiring loom,tank breather,fuel supply,cylinder compression and found that they were all ok ...................................