And here is another drawing of the same motor.
To me it looks like there is a typo on the first drawing and the 55 was supposed to be 5.5. This 5.5mm specification is the distance between the sprocket teeth and the body of the motor.
The MOT-36250G is designed specifically for electric bicycles and would be a great candidate for a folding bike conversion.
36 Volt controllers can be used with a battery pack consisting of three 12 Volt Lithium batteries that have virtually any Ah rating. Three 12 Volt 12 Ah Lithium batteries would be a great choice for a 250 Watt electric bicycle because they would provide a long run time and range. Our 12 Volt Lithium batteries are high quality and available on this page: http://www.electricscooterparts.com/lifepo412v-24vbatteries.html
The THR-110 throttle works with all of our controllers and will be OK with both Lithium or Lead-Acid battery packs.
I can make a wiring diagram showing how all of the parts are wired together however I need to know which controller you want to use first because I need to base the wiring diagram off of the controller.
It is no problem for us to ship parts to the UK. In fact we ship parts to the UK on a weekly basis. Shipping rates depend on the total weight of the parts in the order. Shipping Lithium batteries to the UK requires choosing UPS or FedEx as the carrier, as the Post Office (USPS) will not ship Lithium batteries that are as large as ours are.
If for example a package that weighs 10 pounds (4.5 Kilograms) is shipped with USPS the rate would be around $95 USD, and if shipped with UPS or Fedex the rate would be around $180 USD. There will also be import taxes, duties, and fees payable to the carrier when the package is delivered.
Please let me know if you have any further questions.