Hotrodding the GS

Discussion in 'GS Boxers' started by Poolside, Nov 18, 2010.

Thread Status:
Not open for further replies.
  1. ericm

    ericm Long timer

    Joined:
    Sep 12, 2002
    Oddometer:
    1,358
    Location:
    Santa Cruz Mountains, California
    I don't know of any BMWs that were spec'd to run on 87. Maybe some of the detuned low compression airheads, but my '77 R100RS needed to be dual plugged to run on 91.
    My 1999 1150GS would ping on 91.
  2. Poolside

    Poolside Syndicated

    Joined:
    Apr 1, 2003
    Oddometer:
    11,887
    Location:
    Silicon Beach, CA
    Thanks for chiming in fellas, and here's my two cents, luckygrownup.

    As Carlo said, the boxer motor isn't operated at what you would call a rich mixture anywhere in the operational range. Eric is on the track too. Exhaust popping for the boxer and Motronic combination is caused by the mixture swinging too lean to combust. The unburned oxygen and fuel gets ignited with-a-pop during the next exhaust stroke.

    And a slight adjustment to Eric's comment. The IICE Air richens up the mixture during leading throttle acceleration, and pays small dividends during transient throttle. The big increase to transient throttle enrichment is from the IICE Cool.

    <BR>
  3. Wallowa

    Wallowa Diver Down

    Joined:
    Nov 30, 2006
    Oddometer:
    5,765
    Location:
    NE Oregon

    Did I miss the release and sale of the IICE Cool? Or is this a "tease"..:D
  4. Y E T I

    Y E T I Unpossible

    Joined:
    Apr 26, 2007
    Oddometer:
    8,469
    Location:
    San Diego
    +1 :ear
  5. bracky72

    bracky72 Long timer

    Joined:
    Feb 22, 2011
    Oddometer:
    1,068
    Location:
    Charles Town, West Virginia
    You guys didn't get yours yet? There was a big "cool" sale last month! Oh the power!











    J/k :lol3
  6. Aberdeen

    Aberdeen Gypsy Rider

    Joined:
    Dec 16, 2005
    Oddometer:
    325
    Location:
    Bluff Country, MN
    Been thinking about options for quite a bit, and I'm gonna go with this!!

    Just did a valve clearance and new plugs - TBS was good.

    '05 GS w 60K on the clock. Looking forward to what you have to offer!


    Cheers! :freaky
  7. sarelp

    sarelp Been here awhile

    Joined:
    Aug 3, 2008
    Oddometer:
    136
    Location:
    Southern Indiana
    Just got mine ordered !!
  8. Poolside

    Poolside Syndicated

    Joined:
    Apr 1, 2003
    Oddometer:
    11,887
    Location:
    Silicon Beach, CA
    <BR>Thank you to everyone for all your recent orders! We certainly appreciate it.

    <BR>
  9. Poolside

    Poolside Syndicated

    Joined:
    Apr 1, 2003
    Oddometer:
    11,887
    Location:
    Silicon Beach, CA
    Alright, I'm back, and here's what's happening. In between making up ice packs, trips to the doctor, and preparing meals I got a pretty good amount of work done. It looks like a batch will go into the epoxy on Saturday, and should go out on Monday.

    My schedule is a little different too, at least for the next couple of weeks. I planned for my stay up north to last as long as four weeks. As it turned out it was only half that. That means for the next two weeks IICE Air assembly owns me essentially full time. I'd call that good news all around.

    <BR>
  10. Andrew

    Andrew Optimus Primer Super Moderator

    Joined:
    Sep 25, 2001
    Oddometer:
    18,159
    Location:
    Eastbania
    Cool! :thumb

    :augie
  11. Poolside

    Poolside Syndicated

    Joined:
    Apr 1, 2003
    Oddometer:
    11,887
    Location:
    Silicon Beach, CA
    I wish I'd have had time to stop by Berkeley/Oakland and visit you folks in the East Bay. Next time.

    <BR>
  12. BMWzenrider

    BMWzenrider The Road Scholar

    Joined:
    May 9, 2003
    Oddometer:
    1,175
    Location:
    CheeseHead Land...
    Thanks for the kudos!
    I see that others have already chimed in to help answer your original queries.
    For your follow up question, you just needed to read the second paragraph of my original post to get an answer... :deal

    The R1150R has the same intakes and chip as the GS model, it is just sized for those of us who have trouble holding up a full-sized GS and with a bit taller top gearing. So my data should be somewhat relevant for on-road comparisons.
    It was cold and raining when I rode this bike up the Dalton, so I wasn't saving receipts and writing down my mileage... :wink:


    As others have pointed out, making the mixture more rich is one way to combat detonation. And that is just what the IICE-Air does when wrenching the throttle open (leading throttle).
    On both of my bikes I have noted much less tendency for the bike to ping under hard acceleration since installing the IICE-Air.

    The R1150R used to be very susceptible to pinging when flogging it, even on 93 octane. With the IICE-Air installed I basically have to 'try' to get it to ping even when running plain ole' 87 octane.

    After the initial fun of playing with the bikes a bit more to see just what the unit did for me, I have settled back into riding both bikes about the same as I had before. Although, as others have also noted, I am usually able to cruise at any given speed one gear taller than before installing them; which may also contribute to the improvement in MPG.

    And since 87 octane is both more energy dense {better MPG}, and less expensive. My cost/mile for fuel went down significantly; on the order of 2-3 cents per mile. Which means {for me} the IICE-Air has already paid for itself in the first 3,000 miles.


    The usual disclaimer apply:
    YMMV.
    Past performance is no guarantee of future earnings.
    Filmed on a closed course by professional drivers.
    Do not attempt at home!
  13. BMWzenrider

    BMWzenrider The Road Scholar

    Joined:
    May 9, 2003
    Oddometer:
    1,175
    Location:
    CheeseHead Land...
    You are welcome.
    I am very pleased at how the IICE-Air has improved the drivability of both bikes, but especially my sidecar rig.
    And my wallet is appreciating the added fuel economy on the Roadster!

    Still not seeing any clear pattern to the fuel economy on the sidecar rig because of the scatter in the data, but it looks to be about on par with pre-Air mpg. When you look at the mpg over time graph for the Roadster there is a clear step up to the higher fuel economy after being able to switch to 87 octane with the plug installed.
  14. spartanman

    spartanman regret minimizer

    Joined:
    Oct 17, 2009
    Oddometer:
    1,600
    Location:
    Land of High Hopes & Low Taxes
    "And since 87 octane is both more energy dense {better MPG}, and less expensive. My cost/mile for fuel went down significantly; on the order of 2-3 cents per mile. Which means {for me} the IICE-Air has already paid for itself in the first 3,000 miles."

    It's my understanding that premium and regular gasoline have essentially the same energy content. Premium contains more isooctane, which slows the burn rate to help prevent detonation. I generally run at least 89 octane in my 2002 R1150GSA, and premium if it's not crazy expensive. I've not experienced the pinging many complain about with these bikes. I look forward to installing the ICE Air and running regular. The big unknown these days is how much ethanol is blended in. Mileage drops with increasing ethanol content. Anybody know of any gas brands not cut with ethanol?
  15. Tbone

    Tbone off-ramp slayer

    Joined:
    Dec 29, 2003
    Oddometer:
    4,469
    Location:
    Tampa
    My 2003 1150 pings like a bitch on anything less than 93. In fact when the tach passes through 4k it will still rattle a little if I don't use a gas station with dedicated pump hoses for each octane level.

    Can't wait to get mine!
  16. squatch.f22

    squatch.f22 Adventurer

    Joined:
    Sep 5, 2011
    Oddometer:
    40
    Location:
    Anchorage, AK
    There is an app called "Pure Gas" that gives you the gas stations around your location that don't include ethanol. It has worked for me pretty well up to this point. It's not very easy for planning but good for execution when you're looking for a station.


    - Justin
    2013 1200 GSA
  17. Snowbound

    Snowbound Been here awhile

    Joined:
    Jan 6, 2007
    Oddometer:
    878
    Location:
    Crystola ,Colorado
    I have that App . Good for show and tell , now and again I might be near one of those stations .
  18. 1Gopokes1

    1Gopokes1 Been here awhile

    Joined:
    May 1, 2011
    Oddometer:
    495
    Location:
    North Bama..never lived in the South before
    Thank you for the update Poolside. I can't wait to try it out.

    It has been raining like hell here in CO anyways so nor riding this week
  19. Poolside

    Poolside Syndicated

    Joined:
    Apr 1, 2003
    Oddometer:
    11,887
    Location:
    Silicon Beach, CA
    <BR>Ok. As is often the case, my guess as to the completion of this batch was optimistic. A batch should go into the epoxy tomorrow.


    <BR>
  20. Poolside

    Poolside Syndicated

    Joined:
    Apr 1, 2003
    Oddometer:
    11,887
    Location:
    Silicon Beach, CA
    The quicker burn rate of the regular-grade fuel, along with less spark advance, means the maximum combustion pressure occurs closer to the maximum mechanical advantage point of the crank angle.

    <BR>
Thread Status:
Not open for further replies.