Ben Cox

is this straight from cold or after warming it up? i know mine would conk out if i gave it too much revs 1st thing on a cold morning...

bit late in the day to suggest this, but have you whipped the head off to look at the valves? mine was doing pretty much what you are explaining, turned out the cam chain had slackened/skipped, therefor tthe exhaust valve was hitting the piston every rotation. i'd remedy this quickly, otherwise you will lose all compression and it wont go anywhere (leaving you stranded for a while whilst your dad gets a van (speaking from experience here lol)) Ben