To air down or not to air down

Discussion in 'The Perfect Line and Other Riding Myths' started by Boricua, Apr 14, 2014.

  1. Boricua

    Boricua Been here awhile

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    I ride a tiger explorer with road oriented oem tires. I took it on dirt for the first time in a hard pack well graded but steep and twisty gravely road. The road was a very easy well maintained road, any sedan can do it. Traction was compromised by the amount of loose gravel on top of the hard pack dirt. Going down an 8% grade on a 600 pound beast over a twisty gravelly road can be a bit concerning for a dirt noob. I setup the electornics for the type of surface, abs off, TCC mode for off road.

    My 100 mile ride was 80% road 20% dirt. That would be typical for the type of riding I am doing.

    Should I have aired down the tires and if so how much? Normal pressure is 36 front, 42 rear.

    Any opinions are welcomed.
    #1
  2. Downs

    Downs KK6RBI

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    I sometimes run my STROM at low to mid 20s front and rear and it seems to help a lot especialy the front you just have to be careful going too low because you can get rim dents that in some cases can cause flats
    #2
  3. freetors

    freetors Been here awhile

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    It depends entirely on the surface, the bike, the tires, and your riding style. Some tires on my bike like to be aired up. Others like to be aired down. The only way to know is to try it out.
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  4. Thanantos

    Thanantos Ride hard.

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    I wouldn't air down for a gravel road. I only air down for really loose surfaces like beach sand.
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  5. ALinUTAH

    ALinUTAH Been here awhile

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    Depends on the tires. The various bridgestones they put on so many bikes are horrible on gravel if you don't air them down. I switched to fullbore on the strom and they are great at street pressures. Also noticed a big improvement when I went to T-63 on the little dualsport.

    It also helps if you know how to ride on loose surfaces. And a lack of experience will also make you think it's worse than it really is because any little wiggle will freak you out.

    -al
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  6. r60man

    r60man Been here awhile

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    I agree with this 100%.
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  7. Boricua

    Boricua Been here awhile

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    You are stating the obvoius here. Its not the wiggle, its the sharp turn I can see at the end of the 8% grade that scares me. :cry
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  8. Bucho

    Bucho Long timer

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    Those tire pressures sound on the high side. You could easily run more like 32/36. That is still plenty high enough for street/high speed riding.
    Loose gravel is loose gravel not too much is going to help.
    #8
  9. Boricua

    Boricua Been here awhile

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    I though it was high too. However, that is factory spec. Checked with MOM and yes they go that high.

    I'm looking for piece of mind. I used to ride a Versys. On gravel it was quite a handfull. However, always manage to stay with the rubber side down. I usually ride solo therefore my concern is having to lift the behemoth after a close encounter with the ground. I know I can do it. I did the exercise to prove myself it's a matter of leverage not muscle. Just the idea makes me cautious.
    #9
  10. High Country Herb

    High Country Herb Adventure Connoiseur

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    I would agree with that, as long as it wasn't low enough pressure that you could tell by squeezing it.

    I tried running 29/33 and banged a rim on the ground. My bike is about 410 lbs, with 180 width Pirelli Scorpion Trails. The bikes with 150 section tires seem to get away with it easier, maybe because their tires aren't as low profile?

    I think running a knobbie like the TKC80 would help, but the Explorer might wear them down quickly.
    #10
  11. DesertTortoise

    DesertTortoise Freedom Fighter

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    Gravel is tough! Especially deep gravel. Get a cheap air compressor (I have the slime one from walmart) and experiment with different tire pressures.
    But practice good technique (and relax the death grip on the bars) and it'll get easier.

    You'll get more confidence and probably won't worry so much about tire pressure like some of the other guys are saying. But try it for yourself.




    #11
  12. jonz

    jonz Miles are my mantra

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    My big bike (950SE) isn't that heavy, probably something over 400 lbs. I air it all the way down to 18 lbs rear/25 lbs front. Tires are Dunlop 908 rear/Pirelli MT21 front. I don't like going lower on the front as embedded rocks are tough on the front rim. If the road was just gravel without a lot of embedded rocks, I might lower the front down some more.

    For your bike, I'd drop the pressure 10 lbs front and rear and give it a try. Maybe even a little more for the rear.
    #12
  13. MAXVERT

    MAXVERT OG on da OC

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    + 1 on these pressures for your daily riding.
    For two up loaded the 42 rear would work.

    If I'm doing a long dirt ride (Ruta 40 Bolivia to Tierra del Fuego :D )
    I'll air down my KTM 990 to 28 to 30 psi.

    Max
    #13
  14. Kommando

    Kommando Long timer

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    If you're that concerned about a gravel road, get a lighter bike.

    Under a skilled rider, a Tiger 800XC can be ridden on technical ATV trails like a dirtbike, and it can also fit a 21" front DOT knob with a capable rear DS tire like a K60. The 800XC is more than capable of blazing slab all day, with a full load and a passenger, at over 100MPH. Why somebody who can't ride gravel without a second thought needs a 550lb+ 1200cc bike for solo adv-riding, in a country with sub-90MPH speed limits, is beyond me.

    With that said, airing down can improve the feel on unpaved surfaces. So can using appropriate tires. So can attending a course of instruction that is focused on riding bigger bikes off pavement.
    #14
  15. InsideThePerimeter

    InsideThePerimeter North GA bound

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    For off road fun I air down my Wee Strom Shinko's to 25 front and rear, no real rocks around to bash rims on where I go.

    For steep down hill grades having the bike in the proper gear- lower - will allow engine braking to slow the bike so you don't ride the rear brake and get that uneasy sliding the back tire feeling.

    And from the post above don't death grip the bars.
    #15
  16. Boricua

    Boricua Been here awhile

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    Why a large bike? Because riding 500 miles in a single day on the highway in a smaller bike is literally a pain in the butt. I can take a couple of hours of uncertainty on gravel for many hours of comfort on road :D
    #16
  17. Anders Green

    Anders Green NASA Rally Sport

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    Correct tire pressure is going to vary based on... everything. Bike weight, your weight, tire, whether you have any kind of rim lock in there, and your application .(touring, racing, exploring....)

    I ride a Husky TE610, it's about 300 pounds, I'm 230. I can tell you that with Motoz Tractionator tires and rim locks, it has ridiculously awesome grip on twisty smooth gravel roads at 8psi in the front, 12psi rear. I wouldn't try that for more than a few miles, and I wouldn't try it with other tires, and I wouldn't try it with a heavier bike, or without rim locks. So what good is my advice? Very little... except to expose that the "right" tire pressure has a very wide range and is dependent on lots of factors.

    And having a CO2 cartridge to air up your tires gives you a lot of options. :evil
    #17
  18. Kommando

    Kommando Long timer

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    It's not like I suggested a 250cc 2-stroke MX ring-dinger with a rock-hard seat as narrow as a 2x4...on edge. :lol3 You can even upgrade the seat on most bikes these days too. Try some lighter bikes like the Tiger 800XC, F800GS, CB500X, G650GS, KTM 950 or 990, or even a DL650. You might be surprised at the long-distance comfort on some of the smaller and lighter adv bikes. Choosing a 600lb+ behemoth GS over something like a Tiger 800XC because of solo 500-mile comfort in a country with speed limits seems funny to me. There just isn't that much difference in plushiness, and the lighter bike may even fit you better and/or run smoother down the highway with better wind management. Smoothness improvement has actually been reported by riders that downsized from a DL1000 to a DL650.

    I've ridden a sub-400lb thumper dualsport 1100 miles in a day on a stock seat. I've also done cross-continent slab trips on a 440cc twin and an 850cc I4. It's really no big deal, and an aftermarket seat can make it even comfier. The 850 was even more comfortable for long days than the GL1200 we also had in the garage at the time. There's no legitimate reason why a smooth and peppy 450-500lb multi-cylinder with appropriate ergonomics and wind management can't burn 500+ miles/day down the average interstate in comfort.

    My guess is that ego is involved. Let go of your insecurities and be free to try new things. You might be pleasantly surprised.
    #18