wheel PCD/Offset/tyre Speed/tyre size/ratio charts

[Manky Monkey]

I've really never noticed any difference in performance between any of the Reliant trikes I've been involved with. Never checked whether they've had A or B stamped axles. Most have had 15" wheels with 50 profile tyres, giving a rolling diameter of roughly 24". The exception was Muffin's black trike that had 14" wheels, but he had 60 or 70 profile tyres, so they ended up the same diameter anyway. His seemed a little quicker off the mark, but I think that's just because he rides like an absolute loon -he's managed to blow the head gaskets on several engines, which would seem to confirm that.
With 15" wheels you should get suprisingly quick acceleration from 0 to 60 & should be able to cruise comfortably at 70-75mph, gradually winding up from there to a top speed of 80-85, though if you have to slow for any reason it takes ages to wind it back up again. You should have 3 good gears with 4th becoming a sort of over-drive for motorway cruising. Reliants are happiest blatting around country roads. They'll do long motorway hauls, but if that's what you're after, a bigger engine would be more comfortable. I always compare the Reliant performance to that of a classic Mini. Not earth shattering, but nippy enough to make you grin.

[one arm bandit]

with manky on that one, ive got 16" rims with 45 profile tyres works out the same as 15"/50s, probably not as cushion like but i run with 10psi (or they may have not held and be flat i cant tell,WHOS IDEA WAS IT TO GET THESE F******G WHEELS) but 3rd is the man for getting going then 4th just to get the rpm down, ive never had a trike before, but have had  ninja's and aprillia rsv millie's and personally i think the reliant trike is a nippy little thing 0-50mph certainly not to be laughed at and keeps up with any traffic, and if you stamp on the brakes it'll rip your spleen out

[Manky Monkey]

"and if you stamp on the brakes it'll rip your spleen out"
-yeah, I think that's a direct quote from the Reliant sales brochure.

I run my 15"  50 profiles at 15 psi. Any more & the back end gets a bit skittery cos there's not enough weight to get proper traction. 10's probably the absolute minimum or you risk losing the tyre or even having it slip around the rim. It'll also start to "flap" in the middle, causing premature tread wear.
Personally I like hardtails. Even with low profile, low pressure tyres, the ride's not as harsh as you might think -it's just ...fun.