Even just 2 psi can make a big difference on the front tire, depending on where you're inflated to.

My Evo is an FXSTC, which is basically the Softail version of a Wide Glide and has the same 21" front wheel and same tire size (MH90-21 or 80/90-21). The books calls for 30 psi solo or 2 up for the front. The tires I use on her currently (Dunlop American Elites) also suggest 30 for the front.

I find for me, the best tire pressure is 34 psi. It makes it a lot snappier turning than 30 psi and the tire wears more evenly for my riding style.

It's not bad to go 2-4 PSI or more off what the book says to fit your riding style, up or down.

Remember, tire pressures are measured cold, that means in my case 34 psi when the ambient temp is 68°F. For every 10°f over 68°, you need to add one more PSI of pressure.

The max inflation pressure on the sidewall is just that, the max inflation. It is not the inflation the tire needs or wants and not some goal to hit.

 

What a great reply! I wish I hadn't read that previously mentioned post regarding the recommendation of 40 psi. It sure caused me to question many things on the bike. I was stuck in "what the heck happened" mode!

 

My 21 inch Sporty was always set at 40lbs.

 

Cuz you like riding a ping pong ball...
Just funnin with ya Mustard.

 

Rex, have you thought about, or maybe even already tried, to run the OEM recommended pressure of 30 PSI cold just as a test to see what happens? You might like it. Who knows?

 

Confucius say: Do not believe everything you read on the WWW.

 

Remember, tire pressures are measured cold, that means in my case 34 psi when the ambient temp is 68°F. For every 10°f over 68°, you need to add one more PSI of pressure.


Why would you add 1 psi for each 10 degrees over 68F? Increased temp may add that for you.

 

Exactly, except if you are inflating a low or new tire. Then you add the one extra pound per 10 degrees to the normal "cold" pressure.

When checking tire pressure and its reading a bit high. Take note of the air temp before deflating to the normal pressure.

 

Tires are rated for a 'maximum' amount of air pressure whereas vehicles have a 'recommended' amount of air pressure.
If the tire 'maximum' air pressure did not sufficiently satisfy the vehicle 'recommended' air pressure you would be subjected to some sort of failure.

 

Cold temp also means not right after a ride.
My tires can read 5 psi higher at the end of a ride vs reading the psi before a ride.

 

Over the years it looks like HD has changed what the pressures should be on bikes. Sportsters went from 30psi front to 36psi front.

All you can do is if you don't like what is written in the Owner's manual is experiment by increasing the pressure just a little at a time up or down.

 

IMO 40 psi in a 21" tire mounted on a spoked wheel for good reason, 36 psi for the same tire mounted on a mag rim. The spoked rim can survive hits better with 40 psi, curbs, potholes, dogs and slow moving pedestrians ! The mags can take more abuse than spoked rims. Lower air psi with the mag wheel can provide a softer ride.

 

I have always run factory size tires ( or close to factory size ) and run the cold psi that the book says for solo and I add what the book says in the rear for 2 up.
I always check and adjust cold with zero miles driven. I check the air each day before I ride.

If y'all need a suggestion for the best $25 you can spend, I purchased this Joes Racing 5-60 psi Tire Pressure Gauge over 10 years ago and I assume its the same made in the USA quality now. This was the best $25 I have ever spent on my bike, car... Truly "feels" heavy duty in this day of China junk.
You can get it in Amazon too.
JOES Economy Tire Pressure Gauge - JOES Racing Products

 

I personally will Only Run High Mileage Michelin Commander III Cruiser Tires. If the Tires sidewall says 42 or 50 or 60 PSI That's what they get and the Bike is Quicker, a lot Quicker. Plus when you max Air Them it will get better MPG because of Less Drag.

If you run the Tire Pressure as Harley calls for, you will wear them out a lot sooner. That's my take and the reason I do it is to get as many miles on a Set.

The other reason I run Michelin is they are the Best Rain Tire. I used to hate Riding in rain because my Bike and I saw other Bikers slow down in a Rain, the Rear Swishes back and forth and scared the Crap out of me. Michelin will never do that. In the rain they are like riding on Dry Roads.

 

I am not worried about milage on tires I just want them to hold onto the road as well as they can and I am a Dunlap man they were good enough from the factory so good enough for me I usually get 8000 miles on a rear tire

 

I was reading through the forums last week and found a thread with discussion on tire pressure. Regarding the 21" front tire on the Wide Glide, someone mentioned being advised to inflate to 40 psi. Silly me, I had been set at 36 front and 40 rear. I'm 220 lbs and always ride solo.

I checked my tire and sure enough it says 42 psi at max load (467 pounds). I inflated to 40 psi and on my next ride, the bike feels weird as h*ll! Damn near felt unpredictable! Then I think that I need to check my fall away.

View attachment 842277

Fall away is fine. Driving me nuts! Then, I went to the frame and see that it says 30 psi on the front tire. That's a sizable difference! View attachment 842278

Could the change from 36 psi to 40 psi a affect ride influence that much?

30 psi seems kinda low! Is that the ideal pressure level without heavy load?

I've been riding motorcycles for a very long time. Actually, my first motorcycle was when I was 15 years of age and I've not had a day that I didn't own one (I'm 64 now). Been riding Harley Davidson for the last 22 years.

What experiences have you had? I'm dropping my tire pressure back down to 36 psi and when spring returns on Thursday I hope my front end feels back to normal!

I always run what the tire says to run. I may add 2 lbs on a hot day at highway speeds for a long ride, and dropone pound on a cold day on a short 30 mile ride. Most tires are meant to run what it says on the sidewall. To low of a pressure might cause the Dyna wobble. I run recommended pressures and adjust to temps as I said and I’ve never had a problem. Go to a site called Tyre Plex and it will tell you exactly what to run for each model bike and tire size.For my Street Bob it says 30lb in front and 36lb in rear.

 

21” wheel is 5 inches over stock so it needs more pressure. Divide the wheel mfg date by the size of the wheel in metric. Take that number and divide it by your age. Then air up to 36psi. Let out some air put if its too quick or add some air if it feels sloppy. Thats just me tho. Almost 4/1.

 

WTF?

 

"21” wheel is 5 inches over stock so it needs more pressure. Divide the wheel mfg date by the size of the wheel in metric. Take that number and divide it by your age. Then air up to 36psi. Let out some air put if its too quick or add some air if it feels sloppy."

Crap...I've been doing it all wrong!

 

Owner's manual instructions on tire pressure saying the exact same thing:

Just in case you are blind:

Basic principle (in case you're dumb):

 

What i said about researching to the tenths.

Thanks Kyle! Great read right there!

 

Diss the temp charts and fill with Nitrogen (N).

 

You are correct, I was an aircraft mechanic for 20 years in the USAF. Nitrogen does not fluctuate with temperature and is has a very slow bleed off through the rubber. If regular air was use, the tires would explode from the heat of the brakes. Some HD dealers use it but not mine so I go to the Toyota dealer to have them serviced.

 

The nitrogen canisters used to be available at Yamaha dealers ! They were like maybe 10 and 20 Litre bottles that fit standard Schrader valves. Those size bottles are small enough to be carried in the saddle bags or tour packs ! They can be used to top off the tires with low nitrogen. In a pinch the tires can top off with air because air and Nitrogen mix just fine !

 

So........ along the same topic, but going down a small side street, (NOT derailing! ), I used to battle with trying to keep the proper tire pressure in my tires while out on the road for long trips. I always carry a tire pressure gauge onboard, of course, and would have to check the pressures in the morning at the hotel/AirBnB/VRBO/? before we'd head out for the day. Then, I ride to a gas station ?? miles away, recheck the PSI there after the tires have gotten warmed up, burn my right hand on the rear brake rotor, do some math to decide how much air to put in each tire, PAY to get air, burn my right hand on the rear brake rotor AGAIN putting the air in, then go on my happy-ish way. I only needed to do this every few days or so depending on the different climates I'm riding in. Overall tho, a real PITA for sure!!

Now, after watching a video on IG or FB or something, I decided to buy an Airmoto Airmoto - Portable Air Pump and Smart Tire Inflator to keep onboard as well. This way, I can check my tires cold, and top off to the proper PSI right there! DONE! I don't have to worry about any wonky ass pressures or little blisters on my damn hand. I love this thing! It's small, rechargable, and works fast. I can also use it for the next time I pick up a nail or something, plug the tire with my plug kit and fill the tire with this instead of the CO2 cartridges I also carry.

Point is, the BEST time to check and adjust your tire pressure is cold, BEFORE you hit the road for the day. If you're traveling, this is a great way to stay on top of that...............

PS- I am NOT a paid advertiser for Airmoto, just a very happy owner/user, lol!

 

That’s what I run in mine 35 front 40 rear ,, never had any trouble with it ..