airheads and water crossings.

Discussion in 'Airheads' started by Gimmeslack, Aug 18, 2008.

  1. Lornce

    Lornce Lost In Place

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    Click on the thread in my sig line detailing the rebuild my GSPD required after floundering in a suprisingly deep mud hole.

    Viewer discretion is advised.
    #21
  2. Mugwest

    Mugwest .

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    my 81 G/S has always swum nicely-- the depth limit has always been the intake snorkel tubes under the tank, which is something like 2' or so vertical depth. Whenever in doubt at a big puddle, a walk-through or use of a sounding-stick has told me go/no-go.

    the ign and alternator stuff does waffle a little after a deep swim, but it heats off after a minute or so. i change oils as a matter of course after such rides, and rarely have i found any water present. Cheap insurance is my take

    Things that help: silicone grease packed in the spark plug connectors, and a fresh/new speedo-cable boot packed w/ same sillycone grease. That last item has kept water out of the tranny very well-- but i still change tranny and FD oils after extended swimming rides. FWIW: on an old, ratty speedo cable boot i used to get much more water in the tranny, even after a simple road ride in a downpour. A new boot pretty much eliminates that ingress

    Come on in-- the water's fine :D

    best,

    MRP

    edit: per Frank's warning about the bowl vents: i have the indy floats and bowls, which don't have the bowl vent tubes. That may well make a difference in keeping the carbs water-tight as i've experienced
    #22
  3. Gimmeslack

    Gimmeslack furthur

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    What are the "indy" floats and bowls?
    #23
  4. Mugwest

    Mugwest .

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    http://www.bingcarburetor.com/bmw/bmwcvkits.html

    see bottom of page. Independent floats in a special bowl vs the 2 fixed floats as stock. Indies were Bing's 'solution' to dripping, off-mixture in lean angles, better gas mileage, healthy babies, no more dandruff, etc etc. The wisemen have always been lukewarm on their effectiveness. The kit already came on the G/S when i bought it-- most likely i'd not do such a mod on my own nickel. They do seem to work well though-- not as fussy as the stock float setup i had on the RS a lifetime ago...
    #24
  5. Gimmeslack

    Gimmeslack furthur

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    Funny, I just got my Bing booklet in the mail today and was looking at them. :deal
    #25
  6. Prutser

    Prutser Long timer

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    My bike has a nippon starter that dosn't like swimming. The noise is just like a really dry valeo.

    Some helpfull info for my bike in this thread.

    Hope to find more high air intake pics.
    #26
  7. hardwaregrrl

    hardwaregrrl ignore list

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    Hey Mods...can we move this to airheads? thx
    #27
  8. Prutser

    Prutser Long timer

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    Are there people using pre-filters on the original gs/st air intake ?

    If there are ? Could someone share their experience or show some photo's
    #28
  9. Phreaky Phil

    Phreaky Phil Long timer

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    Water in the clutch makes things tricky, in most deep river crossings you are slipping the clutch with some revs on to make sure it doesn't stall, but keep the speed low. Water gets in between the plates and you let the clutch out and you have no drive, then it must force the water out and your off. One of the clutch plates with 4 separate pucs may help with this. The forward facing snorkels restrict the depth of water you can ride through. You have to be careful you don't create a bow wave over the engine as it will go straight down the snorkels. An airhead should be easy to due drown though, pop off the float bowls to drain the carbs, drain the air box and pull the spark plugs. Even better with dual plugs, take the bottom ones out !
    A lot easier than a 1200 adventure. I was with some guys on a trip to Macetown, near Queenstown in New Zealand. It involves 26 river crossings each way. The water level was a bit high and one of the guys drowned his 1200 GS. Difficult to remove the plugs. No air box drain. A PITA. ! !
    #29
  10. DiabloADV

    DiabloADV Semi-Occasional

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    Just because one thing follows another doesn't mean there is causation. Roosters crow, then the sun comes up...

    As you noted, you're not the original owner and who knows if the splines were dry the day you got it...that's among the first maintenance items one should do when buying a used airhead.
    #30
  11. ME 109

    ME 109 Long timer

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    I've had my RS through some deep water, over the cylinders:eek1
    But it was for about 10 seconds, and that fairing, what a beaut! It was like a boat.
    I had a few hundred klm of riding to do after the crossing so any water was long gone by days end.
    #31
  12. davorallyfan

    davorallyfan Commonist

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    [​IMG]

    [​IMG]
    Contemplative Airhead rider.

    [​IMG]


    It ain't a DR..

    [​IMG]
    [​IMG]
    #32
  13. Prutser

    Prutser Long timer

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    #33
  14. bgoodsoil

    bgoodsoil Dare to be Stupid

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    I've been thinking about going to a low pipe on the G/S. Anybody ever tried starting a stalled airhead while the pipe was under water? I've done it in a truck but I don't know if that applies.

    Thanks!
    #34
  15. igormortis

    igormortis Cafe Reise

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    So Prutser, now you've got me thinking about this again. I've been trying to think of a way to keep the snorkels dry, but now you've brought up issues with the carbs in the Sibirsky thread. Where do the carbs vent from?
    #35
  16. Thomas B.

    Thomas B. desert racer

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    Hi Prutser,

    Where did you get that picture from?
    Apart from the airfilter cover I see something strange infront of that. There is a hose attatched to it. What is that?
    To your question from the Sibirsky RR. What I did to my vent tubes in the float bowls is, I drilled them out and glued new ones in that stick out about 6mm to the outside. I bend that end parallel to the bowl and attached a hose to it that goes with the hoses from the gearbox breather and the rearwheel drive breather up to my cockpit. I did that many years ago and never had a problem although there is some fluid in that hose sometimes. (After over water riding)
    I was thinkig of getting a cover for the airfilter, closing the opennings for the funnels and attatching a big hose to it that leads into the cockpit. I got the hose allready but the cover is still missing. I'll try that next year (maybe).

    Hi bgoodsoil,

    I have low pipes on my bmw and was on Island this summer. In one watercrossing the gravel was so deep that it sucked all the power from my rear wheel and the engine died. After checking if the air intake was still above the water (I was standing with the water almost to my hips) I tried to start the engine. No chance. The pipes fill with water and then runs into the engine. It wont turn a bit. We pushed it through, blew the water out of the engine and out of the exaust and the engine started fine again.

    cheers Thomas
    #36
  17. Prutser

    Prutser Long timer

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    Thanks for the reply Thomas.

    The picture was taken at the BMW event in Garmisch-Partenkirchen.
    A friend that took the picture told me the bike was a special from .edelweiss-motorsport.de.
    I cound not find more info about it. I was told that Edelweiss didn't want to share info about that airbox cover.

    The float bowl vent tubes you mention are not in the R100GS bing cabs. In the 80ST 32mm carbs I squeezed them tight after the first sign of stuttering.(it helped a bit but not enough) IMO they are overflow tubes.(correct me iff I'm wrong).
    When the float needles are not sealing, the fuel will leak from those tubes.
    On the R100GS there is a chance the fuel will leak into the cilinder head or further into the engine.(something I have seen many times)
    Iff you take a look at the carbs there is a hole underneath the choke. I'm thinking that could be the weak spot.
    On a picture of an HPN bike there is a hose connected to that part of the carb.
    http://www.advrider.com/forums/showthread.php?t=418019&page=49 Maybe this has something to do with it ?
    #37
  18. Daanbanaan

    Daanbanaan Adventurer

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    Here a better version of the picture

    [​IMG]

    I remember there was a snorkel that ended somewhere between the front of the tank and the frame
    #38
  19. Prutser

    Prutser Long timer

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    After talking about the water being sucked into my carbs while crossing rivers I took one off an old bike and put it under water.
    The overflow tube in the float bowl wasn't leaking.
    [​IMG]
    Left one R100GS Right one R80G/S

    This is what I did ..... Closed the ends of the carb and put some pressure on.
    [​IMG]

    [​IMG]
    This hole was leaking air from the carb.( on both sides of the carb)
    [​IMG]

    On pictures from HPN you can see hoses coming from these holes going up to higher points on the bike.
    #39
  20. Airhead Wrangler

    Airhead Wrangler Long timer

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    Another mystery solved. I wondered what that hose was for:

    [​IMG]
    #40