TB42 Starts fine on gas, rough on petrol

[WattsyGQ]

Hey all, I've got a 1990 GQ Patrol, TB42 carby fed with petrol and gas. Just wondering if anyone would know why my engine starts and idles fine from cold when I have it on gas, and when I switch it to petrol once warm it runs fine, but if I start it from cold on petrol it won't fire properly and struggles to idle, any help appreciated!

[93patrol]

Gas dries out the seals in the carby and can block the idle jet as well.

[WattsyGQ]

Is there any quick way to repair this?

[Bob]

I think you will find that it is tuned more for Gas than Petrol and will run better on Gas