That's
NOT low when you consider how much stronger/higher load capacity the Altimax has over the OE Spec Kendas and the significantly lower weight the Altimax tire & the air inside it will need to support when it's
only carrying a Spyder instead of a car that weighs three times as much!
In fact, there's every likelihood that even with towing a trailer, unless you're well over-loaded &/or travelling really fast for hours on end &/or riding on really hot temp road surfaces then
20 psi will be TOO HIGH for optimal wear, ride, handling, and traction in an Altimax fitted onto the rear of a Spyder! Most Spyders that aren't being ridden with 600 #'s of rider/pillion aboard &/or a 1 ton trailer sitting on the trunk won't need any more than about 18 psi in an Altimax on the rear cos it's a
CAR tire that's built somewhat stronger & heavier than the Kendas are, so it needs less air in it in order to carry the (lighter) load and still let it flex enough to generate the necessary heat to allow it to reach its optimal operating temp & so work at it's best for you! It's only the lightly constructed OE spec Kendas that need higher pressures in them to ensure that the black bits don't flex so much that they over-heat, wear quickly (especially in the center of the tread) &/or disintegrate under the (lighter than a car) load the Spyder places upon them! :lecturef_smilie: