Tire pressure recommendations

[RazzleH]

I have a newly purchased 2017 F3-S with 4000km on it. I just changed the front tyres to Conti Premium Contact 2 tyres 175/55-15 and, based on many forum updates, plan to run these tyres at 16psi cold.
I'll wear out the stock Kenda rear tyre before replacing it with a car tyre. The Spyder F3 owners manual and service manual both recommend 28psi for the Kenda tyre. I see several updates mentioning 18psi for rear car tyres. My question is, what pressures are people running in the stock Kenda? I guess it would be somewhere between 18 and 28, but cannot find much on this.
IanB

16-17 front and 22-23 rear PSI resulted for my F3Ltd in 20k km rear tyre replacedment with tyre worn pretty flat across and not quite down to the wear depth markers. Fronts replaced at 30k km and not quite down to the depth markers. Replacements were for caution and prep for long trips reasons. Original Kendas replaced with Kendas that appear to be wearing much like the originals.

Vigerous, twisty hill country ryding mixed with town and some motorway ryding. I use the 4psi rule of thumb on all my vehicles except for the Spyder because Spyder is pretty light weight, so I set pressures according to my performance and wear paterns. I'm quite happy that this doesn't suit the theories or technical exactness of some others. Keep smiling and enjoy.

 

[bikerbillone]

There's a HUGE difference between a Lehmann conversion; and a Can Am Spyder.
Virtually nothing that they say applies to our bikes. nojoke

Spot on Bob Denman.

 

[IdahoMtnSpyder]

Spot on Bob Denman.

Bob has been long gone from the forum. You responded to a 3+ yo post.

 

[bikerbillone]

Whoops, should have checked the date, my bad.

 

[pegasus1300]

No big deal Bill. I am glad to see this old post revived. There is lots of good information here and for the most part everyone remains civil thru the discussions.I really like liked Peter's post #21. For myself I have used the 10% rule of thumb. I learned this in a dealer service school 50 years ago but don't remember which one. I am on my 2nd rear car tire and it and the 1st wore/are wearing flat across the tread. The first tire went 35,000mi before I replaced it.The current tire a Pirelli has about 20,000+ on it and still looks good so I must be doing something right.

 

[Mikey]

:roflblack:LOVE IT!!

 

[bikerbillone]

Hey Paul, the OldBiker thanks you.

 

[SeniorRider]

Using your method, what cold pressure are you running?

 

[Peter Aawen]

Using your method, what cold pressure are you running?

Just remember that regardless of whatever 'rule of thumb' you use, because of all the variables that can apply, the pressure that works for anyone else may not be right for you & your ryding/braking style & if you are ryding in different temps/different conditions/with different loadings/on different surfaces.... and so anyone else's cold start pressures may not be directly applicable to YOU as anything more than a potential starting pressure in order to work out YOUR ideal pressures! :lecturef_smilie:

That said, while there are a few, some of whom post here fairly often, I haven't come across too many people large enough &/or loading their Spyder's heavily enough to need to run 'normal' car tires fitted to their Spyders at anything much more than the generally recommended 16-18 psi (which is based upon numerous load/pressure calculations for various tires/loads/users AND upon the results of thousands if not millions of user/miles running them. ) After all, apart from the various Kendas & their lightweight construction, once you get a 'real' tire that fits because of the size restrictions & the relatively small market for tires of these sizes, those that work are all pretty similar in construction & air capacity, even if their tread compounds may differ a little, and there's only so much weight you can load onto a Spyder! So the 'effective optimal pressure range' that covers the vast majority of owners/ryders & their particular ryding circumstances becomes correspondingly fairly small!

There are others who may choose to run higher pressures, either because they don't want to use anything except the 'one size fits all' tire placard recommendations, or maybe because they 'like the feel' or are more used to the firmer ride &/or the 'more direct steering' they think they're getting, or possibly it's in the hope of getting better fuel economy, or whatever else it might be they think they'll get from that over inflation, but unless they are amongst the former few 'high load' ryders, they will be somewhat compromising other aspects of their tire's behaviour; the wet/dry performance, traction, puncture resistance, or longevity et al of their tires - some are doing this knowingly to enhance one or more aspects of their ryde; others are doing it unknowingly & without comprehending the tire/ryde compromises they will be making - but it's their ryde, so that's certainly their choice to make! :thumbup:

 

[BLUEKNIGHT911]

Just remember that regardless of whatever 'rule of thumb' you use, because of all the variables that can apply, the pressure that works for anyone else may not be right for you & your ryding/braking style & if you are ryding in different temps/different conditions/with different loadings/on different surfaces.... and so anyone else's cold start pressures may not be directly applicable to YOU as anything more than a potential starting pressure in order to work out YOUR ideal pressures! :lecturef_smilie:

That said, while there are a few, some of whom post here fairly often, I haven't come across too many people large enough &/or loading their Spyder's heavily enough to need to run 'normal' car tires fitted to their Spyders at anything much more than the generally recommended 16-18 psi (which is based upon numerous load/pressure calculations for various tires/loads/users AND upon the results of thousands if not millions of user/miles running them. ) After all, apart from the various Kendas & their lightweight construction, once you get a 'real' tire that fits because of the size restrictions & the relatively small market for tires of these sizes, those that work are all pretty similar in construction & air capacity, even if their tread compounds may differ a little, and there's only so much weight you can load onto a Spyder! So the 'effective optimal pressure range' that covers the vast majority of owners/ryders & their particular ryding circumstances becomes correspondingly fairly small!

There are others who may choose to run higher pressures, either because they don't want to use anything except the 'one size fits all' tire placard recommendations, or maybe because they 'like the feel' or are more used to the firmer ride &/or the 'more direct steering' they think they're getting, or possibly it's in the hope of getting better fuel economy, or whatever else it might be they think they'll get from that over inflation, but unless they are amongst the former few 'high load' ryders, they will be somewhat compromising other aspects of their tire's behaviour; the wet/dry performance, traction, puncture resistance, or longevity et al of their tires - some are doing this knowingly to enhance one or more aspects of their ryde; others are doing it unknowingly & without comprehending the tire/ryde compromises they will be making - but it's their ryde, so that's certainly their choice to make! :thumbup:

:agree: ............. and let me add one other reason for using a lower PSI ..... COMFORT ... the tire itself is part of the over-all suspension system .... because AUTO tires are built a lot stronger than the Kenda's they need less ( much less for the rear ) pressure to work optimally .... this will allow the tire to flex more efficiently and give a much better ride. It will also have better traction , especially in the WET ...... Thanks Peter ..... Mike :thumbup:

 

[cravenfun]

Back in the '80's when we first fitted fat tires on cars/vans we would put a tire chalk line across the tread and go for a ride to check tread flatness and wear across the tread. Of course there still were bias tires also then along with radials.
I'm thinking this still would apply today to help narrow down pressures vs wear patterns with all the individual variables of rider weight and loading.
Just tossing out some food for thought, not tossing bait.

 

[2dogs]

Back in the '80's when we first fitted fat tires on cars/vans we would put a tire chalk line across the tread and go for a ride to check tread flatness and wear across the tread. Of course there still were bias tires also then along with radials.
I'm thinking this still would apply today to help narrow down pressures vs wear patterns with all the individual variables of rider weight and loading.
Just tossing out some food for thought, not tossing bait.

John, this process has been mentioned several times however it never seems to gain any traction, too easy or simple I guess. Tire psi like oil and mpg seem to require a phd before it can be clearly and accurately understood. With the spyder, there is so little tread visible I used the valve stem location on a front tire to mark the tread on all my tires. Saves a lot of time. You don't have to go far to get a good reading. (Disclaimer; this process will get you into the ballpark and hard science will be needed to proceed further.):roflblack:

 

[FrogmanDave]

I used the valve stem location on a front tire to mark the tread on all my tires. :roflblack:

Care to explain this a little further. I'm not quite understanding your method :dontknow: