Engine problems

If you have a bleeding nipple at the top of the cylinder head
Put your coolant half way in between min and max you will need close to a litre
Once that done with the cap still of the expansion tank
Open slowly the nipple you will hear some air coming of and it will eventually start to bubble open and close the nipple by unscrewing and screwing it until eventually you only have coolant without any bubble coming out make sure the coolant level is still between min and max if no more air you are good to go
when you reassemble the top end make sure you fit the thermostat if it was me I ll get a new one just to be safe as if the engine ran dry before it could have damage it
Good luck mate

 

Okay thank you for your help!

 

what romain says is spot on.

i have always done it differently to that, its not so easy with those bikes, but with a bike with a radiator cap and a reservior bottle (ei you can fill the radiator first) i start it up with the rad cap off and gentle rev it in pulses, you know, like 1/4 throttle ish, the let off, 1/4 throttle then let off etc etc.... and keep topping up the coolant but thats if there isnt a bleed screw.

the worst ones to do are derbi sendas, they have only the reservior bottle and a stupid pipe thing that you have to tilt the bike at a dumb angle to get the air out.....

 

Oh hahahah. I will get it sorted lol

 

Well you state you have a jog rr lc which is the same engine as the aerox and don't know your year but mine being 2001 does not have a bleed nipple on the head to bleed the system
So all I do is fill my water bottle with coolant and start the bike leaving the cap off the water bottle and let the bike get to temperature should see a few bubbles in water bottle and should see the level go down top up to fill line
Bob's your uncle fannys your aunt

 

Hahaha yeah thanks!

 

why new head etc , try new head gasket set and some sealer , make sure you torque everything down to recommended settings .