To air down or not on dirt roads

[ScottRNelson]

I'm still trying to figure out if it's worth dropping the air pressure in my tires off road on adventure and dual sport bikes. My usual practice was to drop the air pressure to the 20-25 psi range when I get to the dirt then air back up to the mid-30's when I get back to pavement. But the last few times I've been out riding I didn't bother and it didn't make as much difference as I had thought it would.

The biggest difference is how the front steers on loose gravel or sand. It steers better with lower pressure. But for most of the packed dirt and rocky stuff there doesn't seem to be a huge difference. Tires are Heidenau K60 Scouts on the XR650L and Metzeler Karoo 3 on the 790 Adv R. Don't know if tire type has a big effect here or not. And the KTM will be getting a set of Bridgestone AX41's real soon.

Any opinions or experience in this area to help guide me?

 

[m0t0_ryder]

I usually only air down if I'm expecting a lot of sand or gravel on the ride. Like Death Valley for example.

Most of the mid and high sierra's are dirt and rock.
I prefer the normal tire pressure here.
I have gotten pinch flats with aired down tires in rocky conditions. For that reason I usually forgo air release.

 

[James]

Thanks for bringing this up!

I am riding a 03 WR-450. Michelin AC10 in the front w/ tube, Pirelli MT43 trials rear w/Tubliss.

I run ~14 front and ~10 in the rear everywhere. I don't like going over 55 mph. I have ran 20 front/20 rear all the way down to 15 front/5 rear. If I know I am not going to hit any single track, I leave it higher and drop it when I struggle.

I should mention, that I am ~125 lbs naked. I don't put much down force to the bike and need all the traction assistance I can get.

Watching this thread for others experience.

James

 

[paul cbr]

Adventure bikes are heavy.

I was running 28 PSI on a Motoz Tractionator Rallz on my KTM 1190R and blew out the front rim on a normal dirt road.

I'm trying to decide whether to lace up a new OEM rim or just have Woody's build me a skinny 21x1.85 Excel and deal with tubes again.

 

[1962siia]

I run a pirelli scorpion rally front tire on the 950, which is basically a knobby. It likes being aired down on most off road surfaces. I run it in the mid 20's off road. I run the motoz tractionator adventure rear tire and it doesn't seem to care what pressure its at.

 

[Cincinnatus]

IANA.... dirt-riding expert, but I've been looking at a lot of Bret Tkac's videos & he's saying don't, or at least not much - https://www.youtube.com/watch?v=TStBBZhzEZA

And I didn't air down my tires (90/10) when I went up to 6,752' on a fire road in Weaverville. I did change the mode to "Enduro Pro", but that's it. arty

EDIT - Weaverville is at 2,051', so increase of 4,701'. Divided by 5,280 (1 mile), that's .8903, or close enough to 9/10ths of a mile vertical gain. Yeah, geeking out. :laughing

 

[OaklandF4i]

Scott, I don't have any experience with a heavy adventure bike. But with the 650 I'd think that you wouldn't be getting a lot of benefit from airing down unless you were running some proper knobbies and riding some really technical terrain where traction was critical. And as you said, you were comfortable with the higher pressure on the terrain you were riding with the tires mounted.

Everyones comfort level is different. Personally, on the 650 I always ran 16-18 psi offroad. Anymore and I just didn't have the confidence in the front with a knobbie offroad. In those instances I expected dirt bike performance and traction.

I ran the same 650 with a dual sport tire K270 and lowered my expectations and adjusted riding style... and in those instances the pressure would be less critical. But still would be running just over or at 20 psi and airing back up to 30 psi to avoid chunking on the pavement.

Not just traction, but the ride would be too harsh, deflecting, and bouncing with 30 psi for me offroad on a thumper.

With those Heidenau's, I'm not really sure you are going to get a bunch more traction going to dirt level pressure in the teens and maybe just a compromise dirt/pavement pressure in the mid 20's would work for you. Especially if you are comfortable with it. :dunno

Ultimately, thats what its all about. A compromise between traction, tube/rim protection, longevity, and comfort.

Anyways, just typed a bunch and probably didnt add much to the conversation. :laughing

Just my opinion and experience, others will vary.

 

[ScottRNelson]

Thanks for all of the responses so far. I just wanted to make sure I wasn't missing something.

The XR650L owner's manual actually recommends 22 psi all the time. I don't generally follow that recommendation and run higher pressures. KTM recommends 35/35 on the street and 26/26 off road. I misread the pressure page when I got the bike and saw the "full payload" recommendation of 38/42. I'll quit running it that high now. :rolleyes :laughing

I'll likely save the airing down for when I have the D606 rear on the XR. I'll have a new set of AX41's for the KTM in a few days and will have to experiment a bit with those.

 

[XXshawnXX]

Scott - I typically would air down on my TKC80's on my AT to low 20's and by doing that it was still a bit squirrley so I air downed a bit more to 17/19 and then got a pinch flat in the hills which was not fun.

I then purchased some Anakee Wilds and they indicate or i was "told" that air-downs are not necessary with the anakees. I have ridden a little bit on these tires and so far so good without airing-down.

 

[HadesOmega]

I don't air down anymore. It too much of a hassle. I pick an air pressure that is kinda in the middle for dirt and pavement, for my bike its 22psi. Depends on how heavy your bike is, but if I go lower than 22psi I start bending rims and stuff on rocks. Like LAB2V you'll run out of daylight if you keep on airing up and down. The sections are so long. 70mph ripping through sand washes at 22psi works for me

Heavy duty rear tube and rim lock should hold up for everything

 

[N4teTheGreat]

I'm the set it and forget it type as well. I can run around 19 - 22psi in my DRZ and be fine on pavement with enough give for obstacles and float for washes. I think I set it at around 19f - 21r cold for the entire CABDR. Added benefit was I got away with more than a few bad lines without a pinch flats

 

[1brunoj]

thnx guys: will adjust press accordingly\ a learning experience