Hi again guys thanks lemur for ur reply Iv replaced the full gasket kit which I got for £11 from eBay genuine Dellorto seals Im a little confused about the adjustment screws on the 305 both are on the left hand side of the bike 1 in the centre which iv looked and is the tick over that’s tapered at the end and hits the bottom of the slide to adjust its height all fine so far now here’s where my carb seems to differ from all pics I can find on the net and books manuals ect they all seem to have another screw I’m assuming a fuel screw to the left of the idle one close to the inlet side of the carb but mines is on the right hand side of the idle and closer to the air filter why is this and is it 2 1/4 turns out or 1 turn out as a starting point ?? Thanks again in advance for any help 

From what I recall of a friends Fantic with the Dellorto carb his low speed adjuster was a fuel circuit and not an air circuit so logic when adjusting it might be counter-intuitive to typical.  In the absence of a service manual 1 and 1/4 turns out is a good start point no matter what kind of small engine it is and I would expect to need to turn it in slightly on one of them.

Sounds like you have the slide idle adjusting screw figured out 👍 the idle adjuster screw bumps up against a ramp machined into the slide, opposite side has a slot cut in the entire length of the round slide to follow a guide pin, intent being to stop the round slide from rotating.

Been 6 hours so guessing you already have it running by now.

20 hours ago, bry140 said:

Hi again guys thanks lemur for ur reply Iv replaced the full gasket kit which I got for £11 from eBay genuine Dellorto seals Im a little confused about the adjustment screws on the 305 both are on the left hand side of the bike 1 in the centre which iv looked and is the tick over that’s tapered at the end and hits the bottom of the slide to adjust its height all fine so far now here’s where my carb seems to differ from all pics I can find on the net and books manuals ect they all seem to have another screw I’m assuming a fuel screw to the left of the idle one close to the inlet side of the carb but mines is on the right hand side of the idle and closer to the air filter why is this and is it 2 1/4 turns out or 1 turn out as a starting point ?? Thanks again in advance for any help 

Hi there, see attached screen shot from the 305 manual.

hope this is of help, and make sure you clean the pilot jet, which has another jet concealed. 

Haha 6 hours lemur Iv spent about 3 days messing with it the post that Iv received on here are the first definite answers Iv had so il have another go tonight anyway thanks lemur and fantic.156 for ur help I miss bill pye for his mass of knowledge