If its a 450-5-15
http://farm6.staticflickr.com/5160/7423464674_41ec40f732_n.jpg
Then here's a place... http://www.bearingstation.co.uk/Products/Belts/Timing_Belts/5M/PHG450-5M-15
If its not 450 then have a look at the index page and select the correct length...
Connecting the halls may give smoother start.
The wires are taped to make it easier for threading the wires through small holes that may be needed in a box where the controller fitted, just insert the wires into the supplied socket, copying the colours so that red goes to red and so on.
Edit:-...
Heat shrink is normally 2:1 so as your smallest measurement is 2" anything greater than 2" but smaller than 4" will work ok .... I'd recommend 2.5" as being most suitable for a 2" dia
One reason could be
Limiting speed to people who may ask for a test ride but lack the skills / experience that are required at higher speed, ie limit them to 10 Mph or so without having to alter the Speedict, this is an issue when giving / allowing test rides several times a day, far easer just...
That's a pity...The cost of upgrading to 4s or 5 spoils the fun:D
Far far cheaper then to get an android phone just for use on the bike.
Is it possible to set the Speedict to have a default low speed setting that can be automaticly changed to high when the phone is within range ?