May 19, 201412 yr Hi Ive got a 2010 gasgas 300 racing that isn't running very well and believe it could be a cylinder head o ring issue. when starting the bike after been stood a week the bike runs very poorly for the first minute or so and the bike gets very hot until it clears itself and then will run ok and temperature will be fine after that On low or high revs but if a short snap of throttle is required then it splutters and won't rev crisply. When I looked into it the plug is black but when checking the coolant there's a grey coloured sludge in the filler cap (see photo) but no visible loss of coolant. Could this be a cylinder head o ring problem and coolant is getting into the cylinder or oil/fuel mixture into the coolant? Ive altered the mixture screw both leaner and richer and it makes no difference to the engine when a small blip of throttle is needed.
May 19, 201412 yr Also interested. Have a similar sludge with my VW aircooled pipe buggy (sludge in oil fill up resiviour).....so cant be coolant in the oil. ???
May 19, 201412 yr Author My dad has a fiesta which does the same as your buggy. Its due to condensation mixing with the oil around the oil filler reservoir. With the bike I think I've found what is causing the grey sludge. The small o ring sealing the two inserts for the cylinder head is leaking which seems to be causing the coolant to oxidise and create the grey sludge stuff. Just need to sort out the poor running now
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.