Hypurone, I can only agree that you are absolutely right about there being a Minimum Pressure as well as a Maximum, & that it's a helluva lot harder to define than the Max. But I believe the most significant issue for us as Spyder Ryders is that many people are either sticking with the pressures required for the very lightly constructed Kendas & using it in the car tires they are now running, or that they are running car tires and continuing to run the pressures those tires needed under something waaayyy heavier!! That's why there is so much discussion about what pressures to run in car tires under a Spyder & why some of us are advocating that we should drop our tire pressures to something more suitable, but not too low as to be dangerous!
At the risk of preaching to the converted &/or saying it all again (again!).... Car tires under a Spyder are carrying a far less load than these tires are capable of supporting at their labelled Maximum pressure, & just like similar sized tires under a small car rather than a big car require somewhat less pressure in them than they would under that big car in order to do the job properly & SAFELY, (a big car which might weigh in much closer to the tire's published max load & therefore need a pressure closer to the tire's max pressure) then so the same sized tire under an even lighter vehicle like our Spyders requires proportionally less pressure in it to do the job safely & properly than it does under the small car! :lecturef_smilie: And that is reflected on the pressure/load charts & tables that just about every tire manufacturer will have produced somewhere - except very few of them ever expected a vehicle load as light as our Spyders, so they generally don't go that low with their published pressure/load figures!! But if you ask them nicely, possibly after searching for & finding the right person in their organisation, you can sometimes get them to either show you the 'lower loading' figures or get them to do the calcs for you to provide the appropriate pressures for your Spyder's loads. And some have done that - the pressures Mike & I have been suggesting reflect that! :thumbup:
Not only that, but since people started running car tires on their car rims under their Spyders instead of running the very poor quality controlled Kendas, there have been literally millions of miles of On Road/Real World Testing conducted absolutely free of charge to BRP, (some of us have even meticulously checked pressure increases & tire temperature increases just to make sure that the pressures being used are not harming the tires & are within or at the recommended/optimum rates) There are 'tools' & 'rules' that I (& some others?) have previously mentioned that you can use to help make sure the pressures
you are running are appropriate, & we've made suggestions about what pressures work & what doesn't. However, Pretty much all of this has confirmed that not only are car tires capable &
safe under our Spyders but also, when run at the lower pressures that have been previously mentioned (without going to low) they will provide significantly better ride, traction, wear, handling, etc than the Kendas do, basically excelling at all those things that most Ryders are searching for from their Spyder tires & telling BRP the OE tires just don't do for them.... :dontknow:
Sure, some Ryders may go a tad lower than possibly ideal in order to benefit from the increased traction that allows, at the cost of a spongy ride & the less direct steering that results; while some may keep their pressures a little higher than ideal in order to maintain the firmer ride & more direct steering/less rolling resistance that higher pressures can deliver, at the cost of less traction & harsher ride; but that's
their choice & hopefully
most have now come to terms with the concept that running pressures that are
too high in a car tire under their Spyder WILL compromise ride, wear, & traction, but (until the limits of traction are reached) the lesser rolling resistance will give you some pretty direct steering; while going
too low WILL compromise wear & give you a spongy ride & sloppy directional control as well as markedly improved traction (at least until that 'hold the tire on the rim' level is reached/passed) & maybe the tire overheats. :dontknow: Hopefully....
That's why some of us here have been suggesting pressures that would allow people/Spyder Ryders to try for that 'ideal compromise' & aim for the best mix of all outcomes, but it is all a game of compromises -
* stick with the Kendas & their recommended pressures, the compromise is that you'll hafta accept crappy performance, wear, handling, etc (noting that experience has show these tires are sooo poorly constructed that varying pressures makes NO difference at all & some are so badly made that you can't avoid the vibration, wobbles, crappy traction, or sloppy steering they provide);
* fit car tires & run car pressures, & the compromise is that while you'll get really direct steering you also get a pretty harsh ride, accelerated centre of tread wear, & poor traction,
especially in the wet;
* fit car tires & run the pressures some of us have been suggesting, & the compromise is that you'll get pretty good steering response (but not the overly direct response offered by higher pressures), you'll get a great ride (but not too soft & spongy, & not to harsh & firm), & very even wear with reasonable if not long tire life as well as great traction; or
I suppose you could also choose to...
* fit car tires & run pressures that are really too low & run into the tire life & safety issues hypurone mentioned..... but I don't know why you'd choose to do that, unless maybe you think choosing tires & pressures is sorta like living in Goldilock's land!

:roflblack:
Sorry about the epic (again!) but it's not a straightforward & simple subject, nor is it easy to discuss when you have such a wide ranging audience, altho there are a few points that I hope are now clear to those who weren't previously sure! :thumbup: