Tire PSI

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bfowler
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Tire PSI

Post by bfowler »

What tire pressure should I inflate my tires to?
I bought some michelin s1 90/90-10 tires and will be using them with a tube on the elite rims. Just curious what PSI I should use in the front and back? Manual says 18 PSI in the front and 33 in the rear for the stock 3.0-10 tires but that seems low compared to the 42 max psi thats on the side of the 90/90-10 tires. Should I inflate them both to the same PSI or should the rear one have a bit more than the front. Thanks guys.
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swimmingfree
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Re: Tire PSI

Post by swimmingfree »

i run 40 in the back and 35 in the front...
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spreeinkc
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Re: Tire PSI

Post by spreeinkc »

The max rating on a tire is always going to be higher than the recommend pressure. I would just set it by feel/looks. You want just a slight bulge (when sitting on scooter) so that the tire make the proper amount of contact with the ground. Too little or too much will both decrease tire life and negatively affect the handling. I'm not saying to go with what manual says per say because you have a totally different type of tire than it was designed for. I've not ran a tubeless tire on a scooter but I would assume the sidewalls and overall thickness and stiffness would be more than the stock tire so I imagine the pressure needed for them would be different but I don't know which way. Recommended tire pressure is always going to be what ever pressure makes the optimum tire contact with the ground. (not the most contact but just the right amount of contact which is usually just a slight bulge)
bfowler
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Re: Tire PSI

Post by bfowler »

Yea I know that I shouldn't run the max PSI. I know a lot of people here have run their scooters on elite rims with 90/90-10 tires with tubes so I was hoping people could chime in with the PSI that they have used.
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Wheelman-111
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Re: Tire PSI

Post by Wheelman-111 »

Greetings:

Like most things, it depends...
If you want grip for braking and cornering, lower pressures increase the contact patch and bite. Bakaracer once said he uses pretty low PSI for track use. Maybe even lower than spec by 10-20%

If you want better mileage through decreased rolling resistance, go higher by 20%. I use sidewall max for top speed testingtesting, and found grip acceptable for street riding so Iseldom go back and drop air. These things self-deflate someso check weekly.
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bfowler
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Re: Tire PSI

Post by bfowler »

So what do you guys use? Just looking for some numbers for the front and rear psi. Thanks.
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Re: Tire PSI

Post by maddog »

32x32 psi for the past 20yrs. rough roads will let air out so check psi weekly.
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Dio89Elite
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Re: Tire PSI

Post by Dio89Elite »

I run 33-35 for my rear with the same tire. I aim for decreased rolling resistance and higher mileage, grip is acceptable for most street riding. I run 33 front with a diff tire. I still run tubes (because my rims are the originals and are not made for tubeless).

To be honest it varies with each tire; I start with a couple of lbs lower than max (or max) then go from there. If it feels a bit too hard, I deflate one or two lbs (or three) and then ride and see how it feels then. If it feels alright, I'll keep the air pressure (write it down somewhere so that you'll have it for future reference). Different brands feel different, I just put on a Kenda for my rear, running 35 but feels a bit stiff, will deflate a couple of lbs and then see how it feels then, I'll go up or down in #s until I feel satisfied.

There's always variables in the #s due to rider preference, rider style of riding (agressive? cruiser?).
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Re: Tire PSI

Post by bfowler »

Thanks for the replies. I'll start off with 33 in the rear as manual says since I'm pretty light myself and maybe 27-30 in the front
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