says if you are using UK bank statements it is the last 3 months of statements with each one showing an excess of £10,000. That's what I had to provide when I made my application last December.
The last couple of times I have applied for a single entry non o E visa in the UK this was a requirement. The reason for visa was being over 50. First application was pre covid. The second one earlier this year. Both times uploaded the bank statement as requested, visa issued within 3 - 4 days.
The only one comment I would make is that if you plan to stay long term in Thailand try to open an account in the Province where you will be staying. Otherwise its just a pain. To get anything done or changed you have to deal with the bank in the Province where the account was opened. If you use your ATM card out of Province you will incur a charge.
I think you would need a full UK motorcycle along with an IDP which is stamped up for motorcycle. And as I understand it this would be valid for 90 days after which you would need a Thai licence.