Harder steering after laser alignment

[wrb3004]

I have a dumb question and very curious about how the rear tire pressure affects the handling? I have Formoza's on the front and an Altimax on the rear and have been running 18# all around. I have played around some with the fronts from 15# to 20# but have not played around with the rear yet. How would a higher pressure make a difference? Just curious. I'll have to try it. Thanks.

[BLUEKNIGHT911]

I have a dumb question and very curious about how the rear tire pressure affects the handling? I have Formoza's on the front and an Altimax on the rear and have been running 18# all around. I have played around some with the fronts from 15# to 20# but have not played around with the rear yet. How would a higher pressure make a difference? Just curious. I'll have to try it. Thanks.

At 18 psi your ( REAR ) tire is working at or near it's optimum performance capabilities ( perfect is in-determinable ) .... Mike

[trikerbiker645]

Ok everyone,
As the Op, here is what I've done and came to : I drove my buddy's and he drove mine. Almost identical as far as tires we put on, mileage, the way we ride....Blah..Blah.. Blah. So after today's ride and having added air pressure to 22 psi fronts and 24 to the rear the bike runs and handles fine in relation to my buddy's. In fact he stated that after driving his I'd probably think mine steered easier and better, and he was right. All's good. NOW, i will need to watch front tire wear to see how they do but at this point with more air pressure in the front tires I'm liking it again, Thanks for everyone's 2 cents. Safe Riding!

[irvin48]

good info here. have to try some of the different settings. may have the federals on
by sat.

[BLUEKNIGHT911]

Ok everyone,
As the Op, here is what I've done and came to : I drove my buddy's and he drove mine. Almost identical as far as tires we put on, mileage, the way we ride....Blah..Blah.. Blah. So after today's ride and having added air pressure to 22 psi fronts and 24 to the rear the bike runs and handles fine in relation to my buddy's. In fact he stated that after driving his I'd probably think mine steered easier and better, and he was right. All's good. NOW, i will need to watch front tire wear to see how they do but at this point with more air pressure in the front tires I'm liking it again, Thanks for everyone's 2 cents. Safe Riding!

Here's the thing if you want super easy steering ... just keep increasing the air pressure to the front tires , until they practically STEER themselves, and go to " zero " toe-in....... But remember what you will get will have to be paid for in traction , when it's dry and especially when it's WET....... My opinion relies on what Science tells me .... not what someone's BUTT says ...... there is no offence intended in anything I've said .............. Mike

[newbert]

Here's the thing if you want super easy steering ... just keep increasing the air pressure to the front tires , until they practically STEER themselves, and go to " zero " toe-in....... But remember what you will get will have to be paid for in traction , when it's dry and especially when it's WET....... My opinion relies on what Science tells me .... not what someone's BUTT says ...... there is no offence intended in anything I've said .............. Mike

The effect of increasing the air pressure in the fronts makes perfect sense. It's a balancing act between steering ease and overall traction. I've also felt that steering on my 2016 F3-T felt a bit heavy so, based upon the comments in this thread, I've decided on increasing my front pressures in one pound increments to try to find my sweet spot. (I was at 18 psi originally).

I guess that my questions are:

1. How high is too high with regard to front pressures (with the OEM tires) before you run the risk of blowing one of them (leaving lowered traction out of the equation)?

2. What effect does increased pressure have in the rear tire (with OEM tire)? Again, how high is too high (leaving lowered traction out of the equation)?

Thanks!

[BLUEKNIGHT911]

The effect of increasing the air pressure in the fronts makes perfect sense. It's a balancing act between steering ease and overall traction. I've also felt that steering on my 2016 F3-T felt a bit heavy so, based upon the comments in this thread, I've decided on increasing my front pressures in one pound increments to try to find my sweet spot. (I was at 18 psi originally).

I guess that my questions are:

1. How high is too high with regard to front pressures (with the OEM tires) before you run the risk of blowing one of them (leaving lowered traction out of the equation)?

2. What effect does increased pressure have in the rear tire (with OEM tire)? Again, how high is too high (leaving lowered traction out of the equation)?

Thanks!

... I'll try to answer this as best I can ... One problem here is there is No real scientific or actual real world testing Data for the Kenda tires .... THAT ARE AVAILABLE TO THE PUBLIC .... it's a mystery tire .... so in all honesty anything I could say about Kenda's would be anecdotal at best , and that's not something I do on tires ..... but #1.... The tire Should have a Maximum pressure rating on the sidewall ... all Car & Truck tires do ____ #2..... the same applies ................... with Auto tires the reason Peter and I recommend much lower PSI's in front and rear has to do with their construction ( ie strength ) .... they don't NEED high psi to maintain their roadworthiness .... The POORLY made Kenda's DO !!!!! ........ Mike

[ThreeWheels]

QUOTE=newbert;1291705The effect of increasing the air pressure in the fronts makes perfect sense. It's a balancing act between steering ease and overall traction. I've also felt that steering on my 2016 F3-T felt a bit heavy so, based upon the comments in this thread, I've decided on increasing my front pressures in one pound increments to try to find my sweet spot. (I was at 18 psi originally).

I guess that my questions are:

1. How high is too high with regard to front pressures (with the OEM tires) before you run the risk of blowing one of them (leaving lowered traction out of the equation)?
There should be a max pressure rating on the carcass of the tire, as well as a maximum loading. Captain obvious says "Don't go above the max pressure rating". In practice, if you're anywhere near the max pressure rating, the front end will be so twitchy that you won't be comfortable riding it. I like your idea of going up in 1 lb increments.

2. What effect does increased pressure have in the rear tire (with OEM tire)? Again, how high is too high (leaving lowered traction out of the equation)?
The Kenda rear tire is only two ply. It is not very stiff. While riding at highway speeds, the center of the tire balloons out so the contact patch is reduced. This increases the wear on the tire, which is why the Kenda rear tires are only good for about 10K miles or so. Increasing the air pressure too much only exaggerates this. True care tires are 4 ply and don't balloon out as much.

Thanks!QUOTE

[newbert]

QUOTE=newbert;1291705The effect of increasing the air pressure in the fronts makes perfect sense. It's a balancing act between steering ease and overall traction. I've also felt that steering on my 2016 F3-T felt a bit heavy so, based upon the comments in this thread, I've decided on increasing my front pressures in one pound increments to try to find my sweet spot. (I was at 18 psi originally).

I guess that my questions are:

1. How high is too high with regard to front pressures (with the OEM tires) before you run the risk of blowing one of them (leaving lowered traction out of the equation)?
There should be a max pressure rating on the carcass of the tire, as well as a maximum loading. Captain obvious says "Don't go above the max pressure rating". In practice, if you're anywhere near the max pressure rating, the front end will be so twitchy that you won't be comfortable riding it. I like your idea of going up in 1 lb increments.

2. What effect does increased pressure have in the rear tire (with OEM tire)? Again, how high is too high (leaving lowered traction out of the equation)?
The Kenda rear tire is only two ply. It is not very stiff. While riding at highway speeds, the center of the tire balloons out so the contact patch is reduced. This increases the wear on the tire, which is why the Kenda rear tires are only good for about 10K miles or so. Increasing the air pressure too much only exaggerates this. True care tires are 4 ply and don't balloon out as much.

Thanks!QUOTE

Thanks for the replies, Mike and 3W. That clears things up for me.

[Spyder_Cowgirl]

All this discussion of tire pressure is giving me a headache Seriously, though, I just had a Yokohama S-drive put on the rear of my RT and asked that the dealer start at 24 lbs (considered a little high, I know). But, here is my plan to check that I have the "best" pressure for this tire (did similar with the Kenda and it was only valid when the tire was new). We have two miles of dusty gravel to negotiate from our house to pavement. Additionally, we have some fresh pavement at the end of that two miles ... so, one of these mornings when traffic is light, we will take the down our dusty road to the fresh pavement, travel a mile or so and stop to see if there are any "dust" left on the tire. Too much pressure and there will be a dark line down the middle; too little and the dark lines will be at the edges; just right and the entire surface will be dark. When I did this with the Kenda .... 26 lbs was the optimum pressure and I got just a shade under 11K out of that rear tire (so I think I chose well). The fronts are showing even wear, and no cupping, so I am not quite ready to change them.

So, to our tire experts (that have studied tire science -- Mike and Peter) .... does this sound like a reasonable way to determine a good pressure for my new tire?

All the best ..... Ann

[BLUEKNIGHT911]

All this discussion of tire pressure is giving me a headache Seriously, though, I just had a Yokohama S-drive put on the rear of my RT and asked that the dealer start at 24 lbs (considered a little high, I know). But, here is my plan to check that I have the "best" pressure for this tire (did similar with the Kenda and it was only valid when the tire was new). We have two miles of dusty gravel to negotiate from our house to pavement. Additionally, we have some fresh pavement at the end of that two miles ... so, one of these mornings when traffic is light, we will take the down our dusty road to the fresh pavement, travel a mile or so and stop to see if there are any "dust" left on the tire. Too much pressure and there will be a dark line down the middle; too little and the dark lines will be at the edges; just right and the entire surface will be dark. When I did this with the Kenda .... 26 lbs was the optimum pressure and I got just a shade under 11K out of that rear tire (so I think I chose well). The fronts are showing even wear, and no cupping, so I am not quite ready to change them.

So, to our tire experts (that have studied tire science -- Mike and Peter) .... does this sound like a reasonable way to determine a good pressure for my new tire?

All the best ..... Ann

.....No , you are doing the " Modified BUTT method " ..... You really have two methods on the PSI thing .... Science ( Peter & I ) or " the how my Butt feels method "., I stated above the Crapenda is pretty much a Mystery Tire .... and for " ANY CAR " ( because they have practically the same load capacity for the same sizes ) tire 14-15 for front & 18-19 for rear .... I think Peter likes 17 for rear tho .... Mike

[Peter Aawen]

Ann, like Mike said/inferred, that method is just a 'proven to be wrong more often than right' seat of the pants method to determine tire pressures. If you want to bring a relatively easy to use method with high degree of repeatability &/or consistency to 'setting' your cold start pressures on 'normal' Car Tires (see Mike's comments re the Kendas above - they are just so generally so poorly/inconsistently constructed that nothing much really applies!!) you can use 'the 4psi rule' (or measuring tire tread temperatures) to work out &/or confirm that your pressures are in the right ball park, & then adjust up or down to suit your own particular ryding needs & preferences.

Briefly, the 4psi rule looks for a 4psi increase above your cold start pressures after an hours ryding (or after 30 mins ryding if you only ryde that long!) - MORE than a 4psi increase tells you that your cold start pressures were too LOW & amongst other things you are risking tire sidewall damage, explosive delamination of the tire tread/carcass, excessive squirm/sloppy steering, soft & spongy ride, poor handling, excessive fuel usage, excessive tread wear on the outside edges of tread, or possibly even rolling the tire &/or bead off the rim; while LESS than a 4psi increase tells you that your cold start pressures were too HIGH & amongst other things you are risking punctures/cuts in the tread or sidewalls, poor traction, hydroplaning in the wet, poor braking, harsh ride, excessive tread wear in the middle of the tread, &/or 'darty' steering/loss of control/skidding etc etc...... but you just might get phenomenal fuel economy (that is, if you don't die due to those others!!) And all you need to use this method is a reasonably consistent tire pressure gauge/TPMS/FOBO & a couple of minutes before & during your rydes for a while (at least until you learn what pressures will work for you, anyway!)

Another method for checking/establishing tire pressures involves measuring your tread temps across the face of the tread immediately on stopping after ryding for 30 plus mins or so.... the tread temps should be within a couple of degrees all the way across the tread face/contact area, but you need to use a suitable infrared remote thermometer very quickly after stopping or use a fairly expensive & fragile purpose built multi probe tread block thermometer to do this, & unless the temps are relatively even to start with, there is then some skill & experience required to interpret & act appropriately depending upon the results you get. BUT, remembering that there is a direct link between tire tread temps & tire pressures/tire pressure increases, generally it's a whole lot easier for the average ryder to use a tire pressure gauge or TPMS/FOBO than it is to carry & use correctly the right type of thermometer & then play with & interpret their tire tread temps properly....


Or if you want, you too could do the study & learn all the tire science stuff, but even so there's still a heap of weighing & measuring & crunching the numbers etc that you hafta do to get a final valid result, & yet, once again like Mike said, due to the massive safety margins involved in running a 'proper' car tire under your lightweight Spyder instead of a Kenda, the fractions of a psi involved in the variations between brands/sizes likely to fit rarely warrant anything more than just going with the pressures we've already recommended.... but all that stuff STILL makes my head hurt just thinking about it & if you really must have something to guide you more, the 4psi thing is sooo easy to use IF you can ever bother to make the effort to check your pressures! I know the method that I think is the most helpful/useful!

Ps: despite all the above, some people become quite used to/comfortable with whatever handling & ride characteristics their significantly WRONG tire pressures may provide; so it might take a bit to get used to running appropriate pressures that are better in all respects than those you may have been running before; but in time, your bike, your wallet, & bum/back will thank you if you can persist, & you'll generally be a whole heap safer too!

[Wildrice]

If I were to run my RT with 14 in the front and 18-19 in the rear it would handle like a Mack Truck. Turning, for me, becomes very difficult at that low psi and I can always tell when my tires are low because the handling becomes so poor. At 19-20 on the front and 28 in the rear my Spyders handle like a dream.

TrikerBiker, we will be at Spyder Fever in Council Bluffs, IA on August 18-19. Come on down and we will check it out for you.

I agree --low tire pressure causes more friction which results in more effort to turn. I'm at 17psi cold front & 28 psi rear but I'm on a 2015 F3's---I had dropped to 15 psi front in the beginning & didn't really notice too much additional effort--I watch tire pattern wear to verify correct inflation. It amazes me that the front tires state not to exceed 15 psi--what's that all about?--it's inline with my riding lawn mower specs--which tops out at 6 mph with tailwind

[Peter Aawen]

...... It amazes me that the front tires state not to exceed 15 psi--what's that all about?--it's inline with my riding lawn mower specs--which tops out at 6 mph with tailwind

Especially on the front tires of something like our Spyders, Running tire pressures that are too high by just a couple of psi can compromise traction & tire integrity (especially if they are lightweight/poor quality tires) so much that it MASSIVELY REDUCES your braking & steering ability!! It might feel as tho you can steer well (in the dry) & at normal speeds, & it might even give you somewhat better fuel economy, but generally, going too high up front will mean you are not only risking yourself on the roads, but you are also ryding a loosely (very loosely) guided lawn dart that is also seriously risking the lives of any road users around you!!

[Wildrice]

, going too high up front will mean you are not only risking yourself on the roads, but you are also ryding a loosely (very loosely) guided lawn dart that is also seriously risking the lives of any road users around you!! [/QUOTE]



My "guided lawn dart" front tires are rated at 14 psi on the front & I've never spun out on my 23 HP new 46" riding lawn mower yet, it has a tight turning radius & I've never lost traction with my 180# riding body---actually it's top speed is 5.5 mph rounded up to 6 mph.
I know all about tire traction--my turbo Hayabusa's tires are rated at 42 psi--at the drags I launch with the rear at 14 psi & I've ran 60 psi on front & rear land speed racing in the 1 mi on airport strips at speeds You've only experienced in an airplane.
Darrell

[exwinger]

One thing nobody mentioned on the tire pressures ....... make sure your gauge is reading correctly . I checked mine against a buddy's and mine was reading 3lbs lower than his .Used his gauge to correct my tire pressure and what a difference it made . Buy a cheap gauge and the results will reflect it .

[jwulf74]

My wife squealed the tires on our Ariens ZTR the other day. We all just looked and then busted up laughing. She wanted to do a quick mow and tore out of the garage, and made not even a 90 degree turn and squueeelll. It was pretty funny. I forget the pressure, but they run really low like 10 or 12 psi if I recall.

, going too high up front will mean you are not only risking yourself on the roads, but you are also ryding a loosel2y (very loosely) guided lawn dart that is also seriously risking the lives of any road users around you!!

My "guided lawn dart" front tires are rated at 14 psi on the front & I've never spun out on my 23 HP new 46" riding lawn mower yet, it has a tight turning radius & I've never lost traction with my 180# riding body---actually it's top speed is 5.5 mph rounded up to 6 mph.
I know all about tire traction--my turbo Hayabusa's tires are rated at 42 psi--at the drags I launch with the rear at 14 psi & I've ran 60 psi on front & rear land speed racing in the 1 mi on airport strips at speeds You've only experienced in an airplane.
Darrell[/QUOTE]

[Wildrice]

[QUOTE=jwulf74;1292470]My wife squealed the tires on our Ariens ZTR the other day. We all just looked and then busted up laughing. She wanted to do a quick mow and tore out of the garage, and made not even a 90 degree turn and squueeelll. It was pretty funny. I forget the pressure, but they run really low like 10 or 12 psi if I recall.


OK--the race is on--- Ariens ZTR against Kohler powered Cub Cadet. Napping cots & lawn chairs with beverages provided--But Emergency Medevac airlift will not be available. I'll need to oil the driveway for my burnout
Darrell

[trikermutha]

[Peter Aawen]

One thing nobody mentioned on the tire pressures ....... make sure your gauge is reading correctly . I checked mine against a buddy's and mine was reading 3lbs lower than his .Used his gauge to correct my tire pressure and what a difference it made . Buy a cheap gauge and the results will reflect it .

Funnily enough exwinger, for most users & their tire pressure gauges, 'consistency' is far more critical than any significant degree of accuracy This applies especially if they are using an 'aide' like the 4psi rule to arrive at or near the optimal pressure for the tires their vehicle is wearing right now!

It doesn't really matter exactly or precisely what the 'exactly accurate' pressure in their tires might be right now or ever, it's really just a number or label designed to allow us to get to the same level/setting consistently...... and with the 4psi rule, just so long as the 'increase after ryding' target variation onany device is the same difference every time, then you can use that potentially 'inaccurate' (but consistent) device to work out & eventually establish a given point or label or pressure reading on that device that works for you.....

And btw, whatever the EXACT PRESSURE that works for you might be, it's extremely unlikely that anyone else will need EXACTLY the same pressure, largely due to the thousand of little variations & differences in the way different people ryde & the where, the when, & the what of the surfaces & temperatures & loads etc that will exist between what they do & what you do or need or want or feel or... you get the picture!

Still, getting or using a pressure that's within a pound or so of what's 'right' for most is going to be near enough - most of us 'recreational ryders' won't ever be ryding in conditions where the difference of 1/2 a psi or maybe even 1&1/2 a psi will really make all that much difference, but we WILL probably notice the difference that saaayyy 4psi might bring!! That's not to say that there aren't circumstances where exact accuracy isn't called for; but seriously, any tire pressure gauge or TPMS or FOBO that generally reports the same reading for a given pressure 9 times out of 10 is going to be near enough & good enough for the bulk of us/what we do - & that's especially so if the 10th time is only ever a pound or so off anyway!

Sooo, It's really FAR MORE important that we REGULARLY check/confirm & adjust our tire pressures appropriately than it is that we have an 'exactly accurate' tire pressure gauge or reading.... & by regularly I'd suggest at least weekly while ryding, altho I personally check my tire pressures before & after EVERY ryde, & frequently also check them about an hour in on a longer ryde (and I do a lot of them!) After all, your tires are the single most critical vehicle component in keeping you safe whenever you ryde..... without them working at their optimum, everything else is compromised to some degree!

And on that note, here endeth this lesson!