I agree with Manas, You cannot submit RC transfer form without insurance certificate copy.
See Natraj post on Ownership Transfer -
For transferring the ownership of the car, you would have to fill and submit following forms to RTO -
Form 29
Form 30
The forms have to be filled up and both of the parties (buyer and seller) would have to sign and the buyer would have to submit them at the local RTO with the Original Registration Certificate and attested photocopies of Insurance, proof of address and Identity proof.