Recommended tire pressure for 300 lb rider

[jb3472]

Okay so I have a 2008 roadstar with the absolutely wonderful roadwing conversion shock from smokescreen. Got brand new Michelin Commander 2's all I've ever used. Been inflating them to 38 front 40 rear. Yesterday I went on a 5-hour ride and the pressure in my rear tire shot up to over 50 psi in the hot Florida Sun. 10 lb increase seems like a lot? Should I be concerned? Thanks in advance!

[Lug Nut]

Get an accurate gauge first off....no way I der normal circumstances even in 100 degree heat your tire pressure would increase 10 psi. 2-3 at most. 40/38 is fine...I have been using 42/40 after talking with tire techs and a guy who was a test rider for HD and they collected a lot of tire data.

But a good accurate tire pressure gauge. Use the same gauge always...not for just one measurement and then depend on a different gauge for another reading.

[Brad_G]

Great advice about the gauge. You can grab 3 of them and they will all likely read a pound or two different from each other. So having only one to monitor pressure is a good bet. Also don't just get the cheapest 99 cent thing you can find.

[Shores]

It's my understanding that a low inflated tire will heat up more than a properly inflated tire. Maybe jack your pressure up another couple pounds and test again to see if that makes it improvement. Most of us here between 150 and 200 lb run 38 front and 40 rear.

[jb3472]

I'm using an analog gauge and then I use Fobo Bike 2 tire pressure monitoring valve stem caps. They sync with a app on my phone via Bluetooth. So I get a digital readout. Been very accurate in the past? I set the warning limit at 50 psi. Yesterday I rode from North Fort Myers to West Palm Beach and back 5 hours in total. And the rear tire warning went off at 50.2 psi? So I released some pressure and rode it the rest of the way home. What is the max pressure these tires can withstand I guess would be my next question? Thanks guys!

[davej]

I run 40/40 cold pressure and only check them cold with the same gauge and it is a good gauge not a HF cheapy.. If I know the cold pressure I don't care about the hot pressure. It will be whatever it will be. Physics is absolute and can't be changed. lol

[jb3472]

I'm not sure I understand that but thanks for the reply. Lol

[davej]

it means that if you know the cold psi, there is nothing that you can control with the psi change due to ambient air temp and psi after running the tire hot. Physics takes over and changes the o2 gas pressure accordingly. It really just comes down to check the pressure cold and don't worry about it after that. I check mine cold every couple weeks of riding and adjust if needed.

[Shores]

The maximum pressure for a tire should be printed on the side of the tire. That's not necessarily what you run in it because that's just the maximum it can handle. Bikes vary.

[davej]

I think the number on the side is maximum cold inflation not what it can handle when hot. or burst pressure.To bad JD isn't here to answer this one about the sidewall numbers.Being in the aircraft business he knows all of the tire stuff

[Lug Nut]

Absolutely get rid of the space age tire monitoring valve cap super duper Ninja electronically controlled battery backup solar powered freaking gauges lol. By yourself a nice 20 or $30 accurate tire pressure gauge do it by hand. I've never ever seen one of those tire monitoring systems work worth a shit in terms of accuracy and consistency. Ever.

[Father Pobasturd]

I'm 300lbs I run 40 / 40.

[JimK]

300 in front tire and 300 in the back.

[jb3472]

Yeah I think what I've learned is I can't trust these fobo 2 to TPMS sensor valve stem caps. Thank you all for the help!

[MidnightRide]

On a side note, Anne and I combined weigh well over 300 lbs., and we rode the entire RoadFest NW 2022 on around 15 lbs. in each tire. Not intentionally, of course. Ran speeds above 80 MPH on numerous occasions. Shinko's at that--

[jb3472]

lol When I bought the bike, the tires were so old and dryrotted from sitting that they wouldn't hold pressure and I rode it home on the Interstate At 75mph and checked the pressure when I got there...10psi Michelin Comander II's

[MidnightRide]

Yeah when I bought mine and got it home the pressure was 8lbs! I hear ya--

[Shores]

On a side note, Anne and I combined weigh well over 300 lbs., and we rode the entire RoadFest NW 2022 on around 15 lbs. in each tire. Not intentionally, of course. Ran speeds above 80 MPH on numerous occasions. Shinko's at that--

So is that why you were getting that high-speed wobble that we pulled over to the side of the road for? How could you embark on such a glorious ride with all of your fabulous friends without checking your tire pressure?

[MidnightRide]

Yeah but I'm still thinking that my brake caliper was hanging up there on the front wheel, because it never repeated itself after that. Remember when Duke had me kick the caliper? I think that resolved the issue.

As stated in another thread, I'd never checked the pressure in the Shinko's since the dealer put them on a couple of months earlier, and simply trusted him when I shouldn't have, simply because there was no discernible indication that there was a problem, visually or pertaining to handling.

It wasn't until AFTER I aired the tires back up that the handling difference was obvious. Night and day.

But the tires did indeed 'perform' with only 15 psi in each! Gotta salute them for that.

I simply got too busy, but I'd tried to check them before heading up there but my quality gauge wouldn't fit over the valve stem due to hitting the calipers. Once I got the extensions that Lug Nut recommended I was able to quickly check and air-up the tires in a couple of minutes.