The mudflap was no issue with the OEM rear tire, lots of clearance, no rubbing sounds
The OE Spec Kenda is a 'small' tire for its nominal size; the Altimax, not so much -
AND you've gone up a profile in size too, so the Altimax sidewall is a tad taller than the OE spec Kendas, giving you a slightly larger rolling diameter and helping make your speedo/odometer more accurate into the bargain.

hyea: Still, lots of other Spyder Ryders have done that, most without any rubbing/scraping concerns.... so what's the difference between their Spyders & yours?? :dontknow:
Well, on top of doing those things that so many others have, things which definitely
DO increase the
risk of scraping,
even if most of them don't actually,
you've also gone & put enough air pressure into the Altimax to easily carry a 1500kg auto; while it's only carrying what, about 1/3rd less weight, saaay a max of 500kgs of Spyder, Ryders, & load!?!
AND THEN you've installed that mud flap so that it reduces the space available for the wheel to move up & down in
even more than just fitting a taller tire does! :shocked: All of which adds up to the perfect storm, at least when it comes to compromising wheel clearance & creating space/scraping issues! :gaah:
So what is it about those bits that are different between your installation and most?! Cos
those are the things you might have some control over & maybe can adjust/do differently in order to help &/or minimise/reduce the scraping?! :dontknow:
Well, firstly, the Altimax on your Spyder is over-inflated for what it's being asked to do, making it puff up big & tight like an over-inflated balloon.... which really only:
• - increases the tire's susceptibility to puncture cos the tire & tread can't wrap over & around any stones or other hazards, instead punching those hazards into & maybe even thru the tread;
• - increases the tire wear rate in the narrow strip down the centre of the tread, cos that thin strip in the middle is the only bit that ever touches the road in a tiny contact patch, so that little strip over-heats significantly & basically strips tread off more rapidly than it should;
• - means it never lets the rest of the tire/tread compounds etc get to their ideal (& grippiest) operating temperatures, so they aren't working at their best for you either;
• - slightly increases your tire's rolling diameter
AND SO all up, makes it far more likely that your '
puffed up & over-inflated for the load on it' tire will hit/scrape on your mud flap that is somewhat reducing the clearance/space available!!
Dropping your Altimax's pressure to saay.... something between 18 & 20 psi, maybe 22 psi max, is not only likely to bring your tire back down into its optimal pressure for load range, but it will also:
• - reduce that increased risk of puncture, cos now the tread can absorb some of the impacts from road/surface hazards & deform safely over them instead of punching them straight thru the tire;
• - allow the entire tread face to remain in contact with the road surface across a larger contact patch, reducing overall tread wear & improving ride, handling, suspension compliance, et al;
• - allow the whole tire carcass/tread reach its optimal operating temperature, without over-heating abnormally in some sections & remaining dangerously cold in others, increasing the traction the tread can provide & improving ride, handling, suspension compliance et al;
• -
AND SO there's a good chance that even just the slight reduction in rolling diameter achieved by reducing your pressure from that '
puffed up & over-inflated for the load on it' level to something more suitable for the loads imposed by your Spyder versus that of a much heavier auto will at least
lessen the chance of scraping on the mud flap!
Or alternatively you could take the mud flap off the
INSIDE of the fender/wheel arch, where it clearly reduces the space for any tire to move freely as the suspension articulates, and put it on the
OUTSIDE of the fender/wheel arch, where it won't intrude upon the space that's meant to be kept clear for the wheel.
Or maybe you could do
both - Run a 'more appropriate for load' pressure, saaay 18-20 psi,
AND put the mudflap on the outside of the wheel arch?!

hyea: :thumbup:
Over to you! :thumbup: