If you're still running OE Spec Kendas or their clones, then those 20fr/30Rear starting pressures are a bit high, but basically fine; and you could probably even afford to let them drop as low as 16-17ish up front & maybe 26 psi in the rear without causing any real issues
for the tires themselves, altho you might find you notice some changes in ride & handling because you've become used to the feel you've been getting running them over-inflated.... running for too long at anything lower than that in the OE Spec tires or their clones will be compromising their integrity & capability to work safely, risking over-heating and destroying the tire - even without considering their poor quality control & significant failure rate, due to their
much lighter construction than 'normal' car tires, they
REALLY NEED their specified air pressures in order to safely carry the load of your Spyder/Ryker!
BUT,
if you are running non-OE Spec a/mkt tires, ie. auto tires that can carry much higher loads than your Spyder/Ryker at those 20 fr/30 rear pressures instead of a
max of about 18/20 psi fr/rear, then you're
seriously kidding yourself if you think that running them grossly over-inflated like that is doing anything good for you except most likely lightening your wallet a lot quicker than you need to and definitely making you a potential danger to any other road user travelling near/around you! :yikes:
Running pressures
THAT HIGH in auto tires under a Spyder/Ryker is sorta like you choosing to run 50+psi in your car tires cos it '
feels' that you get more direct steering & you might even get better fuel economy.... And you
might, but you'll also be wearing the centre of the tread rapidly; tip-toeing around on a narrow strip of tread in the middle the tread width; then lifting most of that tiny little strip of tread off the road surface during cornering &/or braking besides; risking dangerous loss of traction with any change of direction &/or speed; risking catastrophic tire failure due to the tire rupturing if you hit any obstacles/hazards/debris on the road, or even just if you add a little more load whenever you hit a bump; and a bunch more besides!! :lecturef_smilie:
Even just a little Over-inflation of your tires is actually less forgiving than a little under-inflation
in most circumstances - you can see this for yourself by using a party balloon to represent your tires. Get a couple of party balloons and blow one up to a reasonable size without any risk of it exploding; blow the other up as tight as you can get it to just before it explodes. Then press the first balloon fairly firmly against the wall & slide it along the wall - you'll see/feel that the balloon grips the wall but deforms enough to let it slide along without risking explosion - you can usually even poke it fairly firmly with a finger & it won't explode. Now try doing the same with the second over-inflated balloon - if you are pressing it against the wall just as firmly as you pressed the first, chances are that it'll either skip along the wall without gripping &/or deforming at all, or it'll simply explode! And if you poke it with a finger just as hard as you poked the less inflated balloon, then it's extremely likely that the over-inflated balloon will pop! :shocked:
Now get another two balloons & blow one of them up
juuust a little
less than the first balloon, and the other a
juuust little
more than the second balloon and try the wall slide/finger poke again. The less inflated balloon likely doesn't make too much difference at all; while if the more inflated balloon doesn't explode during the inflation phase, it almost certainly will during the wall slide/poke test. And
THAT is just
a small part of what you risk running over-inflated tires; there's also the extra tread wear in the centre; the lack of it's ability to effectively clear water & resist hydroplaning; the damage you'll be doing to your suspension by removing any ability of the tire to absorb any of the shock loads; the risk of it exploding if it gets poked by anything on the road surface; and more! But if you've been running over-inflated tires for a while, it might '
feel' nice or even right
to you, simply because you've trained yourself over time to erroneously expect that sort of feel! :banghead:
For a/mkt auto tires under your Spyder/Ryker, you need to aim for a pressure increase (& corresponding temperature increase) of about 4psi after an hour or so's riding -
LESS than something close to 4psi means your cold starting pressure was too
HIGH;
MORE than something close to 4psi means your cold starting pressure was too
LOW!! :lecturef_smilie:
Just Sayin' :thumbup: