:agree: And if you 'upgrade' your rim size to a 16" rims, you can't use the same OE Spec 165/55 or 225/50 tire sizes
even if they are made to suit 16" rims - those front '/55' & rear '/50' profiles respectively will be too tall for 16" tires (tires on 16" rims) on the Spyder (hence PPA's recommendation to drop the fronts to 165/50 if you fit 16" rims there!

) the OE spec profiles for 16" rims won't fit into/under the fenders - by going up a rim size you hafta drop a profile or two in order for them to fit, so you'd need to go to '/50' or '/45' at least, or maybe even something like 165/40R16's &/or 225/35R16's instead. :lecturef_smilie:
But be warned, even dropping from a '/55' to a '/50' profile will increase the ride harshness & work the suspension harder, as well as introducing other handling characteristics that, teamed with the Spyder's particular suspension really does reduce overall traction/road holding. So going to profiles as low as '/45' or less
really wouldn't be great on a Spyder (and I can assure you they really
aren't, even in 15" tires! :banghead: )
With the Spyder's suspension design, where the sidewall of the tire & the air that each tire contains forms a large part of the suspension's 'compliance' or 'road roughness absorption', lower profile tires would mean that your ride becomes
SIGNIFICANTLY harsher than it currently is; you'd also increase the risk of blowouts, & you'd probably lose a lot of traction thru tire skip too, over-working the suspension & likely over-heating the shocks to beyond their 'working capacity' if you ride 'spiritedly'..... possibly even exceeding the
spring's capacity for compression/rebound - and all that simply because the lower profile tires simply aren't able to absorb anywhere near as much in the way of bumps & shocks etc from hitting irregularities or obstacles in/on the road surface than a taller profile tire would!! But the lower profiles
might give you (seemingly!)
very direct steering - albeit teamed with harsh as buggry ride & likely also lots of understeer due to the aforementioned 'tire skip' once you picked up speed; but on a smooth enough road or track and at low enough speeds, it
might feel as tho changing to lower profile tires could be worthwhile! :gaah:
Me,
I wouldn't
choose to go lower than a '/50' profile on either end of a Spyder, not even on a larger diameter rim, like those 16" rims you're thinking of - but some have, and just like those people, it is
your choice, cos after all, it
is your Spyder.....
