airheads and water crossings.

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

  1. Warin

    Warin Retired

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    Nice work with the carbs Prutser. I would have made one of the cover plates name "Crosby" - thus having Bing Crosby ...

    It is not just the depth of water that is the problem for the carbys - but also the length - a short deep crossing is OK.. longer than say 4 meters is a problem.

    Did this work? Somehow I think as the low point for the gearbox breather is the gearbox you will still have the problem. If you had a 'Tee' piece with the upper 'Tee' being the air breather and the lower 'Tee' being the drain for the water - seal the bottom of this with enough volume for a fair bit of condensation.

    The final drive is a bit harder to arrange a water trap for... as it mounts pointed down.
  2. Prutser

    Prutser Long timer

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    It does work. Although I haven't been riding that much the last few months. I will give an update when I have been riding the bike a bit longer.

    Ontic did you check how much space there really is to put a good snorkle on the intake ? There is almost no room to put them. I am looking for a permanent fix for my bike. Just can't find a second ST tank to start drilling tubes through yet.
    In the ride report you can see how many crossings we did. Those G650's will not wait 40 times a day for me to mounth the snorkles :rofl

    When I have the second tank I will start but they are hard to find out here.
  3. Plaka

    Plaka Brevis illi vita est

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    You could do the airhorns by having both systems at once. Standard snorkels out the front, High flex pipes out the back. Take the rags out of one and stuff them in the other and go.
  4. bgoodsoil

    bgoodsoil Dare to be Stupid

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    The bottom of this air filter is level with the horns. Using hose like this, it doesn't seem hard to move the intake anywhere you want it.

    [​IMG]

    Maybe you could run the hoses up the side of a standard tank? I think the HPN tank would block that. Or up into the seat? It looks like Rooney ran his in the space under the electrics and turned up in front of the tank. It may be the reason why he chose that particular tank. That seems like the best way to get height even though you have to run 3' of hose. Hmmm......
  5. Rucksta

    Rucksta SS Blowhard

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    I've used this in practice and it works great until a hole or a rock impeeds your progress.
    Better in still water where you don't get a build up on one side.
  6. ontic

    ontic

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    Yeah, I just had another look now, the space to go forward and up the front of the tank is definitely tight. Flipping the airhorns to face backwards might offer a few more possibilities brining the snorkle(s) out behind the seat somewhere?

    If the G650's could handle waiting for the KTM, I reckon they could wait a little while for the old uncle airhead:D but I do understand the desire for a permanent solution.

    I think drilling through a tank to come out the top is a fine idea, my problem is I have read just enough about airbox tuning to be concerned about what it might do to engine performance, and read and practiced no where near enough to begin to figure out how to go about it or understand how to mitigate any negative effects.

    I actually like Plaka's idea about having both systems installed- plugged snorkles plumbed to the base of the airhorns, pull the plugs out of the snorkles, pop them into the airhorns, and off you go. I'd actually use airhorns for the end of the snorkles and use the exact same plugs to make it easy.

    Either way, for the temporary system I am imagining, including getting gloves off and on it would be 1-2 minute job max to switch. Times 40, in one day, yeah, that would suck, but on a day like that I would imagine just running through the un-optimised snorkles inbetween crossings and/or trying to fit in the changeover time during the time you are already waiting for others (people I ride with always tend to cross one at a time thus there is usually some free time available at a water crossing).

    In my reality I won't be needing that much permanent water protection- I want the carbs and gearbox and final drive to be completely waterproof, but I doubt I'll be needing much more height than the stock airbox provides- and the last thing I would want to do is handicap my engine permanently for it. That may not be required though.

    I do look forward to your solution, and I am sure it will be a good one.
  7. bgoodsoil

    bgoodsoil Dare to be Stupid

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    That makes 1 of us :D

    I'm hoping I didn't trash performance doing this. A lot of the big money GS bikes I've seen still run the stock airbox. Gotta be a reason for that. A lot of them run Bings too though.

    However, most of the road racers I've seen have pods. At least this set-up has some intake length. I read an article about intake track length and how more is better at low RPM :dunno

    Rooney did something similar to this and he certainly knows a lot more about bikes than I do. Since I don't plan on testing this set-up against a stock airbox, I guess I'll never know.
  8. naginalf

    naginalf Handy Schtroumpf

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    :lurk

    I was planning on going around the front, left corner of my PD tank and using the space on top of the lobe for a simple, round filter with a bowl type cover held on by a wingnut, eliminating the stock airbox, and moving the battery there. I was also considering making up some plugs for the vent on the bottom of the front cover, sealing the front and top cover along the edges, then making a slide plate for the vents on both so that I can simply plug, slide, go, less than 30second conversion and not have to worry about my electrics shorting out.

    If you're running mikuni's or delortos, you could also run an electric blower to get positive pressure in the intake and avoid water leaks in really deep stuff, also nixes any performance loss issues. Just a thought.

    Or you could install a winch :rofl
  9. Prutser

    Prutser Long timer

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    I'm a big fan of the stock air box. Most airheads I have ridden with pods where only performing in a short rev range and thats not what I like for my bikes.

    It might take a while before I know what to do with the filter set-up because I hate mods that make working on the bike harder than on a stock airhead. It needs to work all the time so I don't have to change snorkels or intake hoses for a crossing. Specially for some trips I'm planning in a wet muddy part of Russia :super

    The cover of the stock air box might not seal good enough if the bike is submerged for more than 15 min.
    Thinking about using some 80cm long plastic tubes with pod filters and than take my bike for a test run to feel how bad that would be.

    A big air box is something that I would like to have on my bike. A set-up with a bigger box than the stock box was working great and gave my bike more low rpm torque.
  10. bgoodsoil

    bgoodsoil Dare to be Stupid

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    I wonder if I could make a box around this air filter. I could get a plastic tupperware dish and cut 2 holes in the bottom the exact diamater of the spigots. I can leave the top open for air to come in. That'd raise my intake height another 3" too.

    If I did that I wouldn't be able to put in the toolbox though. My main motivation for this intake, aside from making those damn top gearbox bolts easier to remove, is to build an aluminum under-seat toolbox that goes all the way down to the old battery tray mounts. It'd hold all my tools, air compressor, jumper cables, etc. without having to keep my boxes on the bike.

    I've got a rivet gun and sheet aluminum but no time to do it right now. I don't think I'd give up that tool box for 3" of intake height.
  11. bgoodsoil

    bgoodsoil Dare to be Stupid

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    Do people really rig electric blowers onto their intakes? I've never heard of that before.
  12. naginalf

    naginalf Handy Schtroumpf

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    Probably not, just a wild thought. You'd probably have to have some sort of electronic controller anyway, but other than the electronics, a 12V blower would be simple to rig up. I have heard of some getto ricers rigging up a leaf blower to the intake. :rofl But I have heard that it's good to have positive pressure on snorkel systems.
  13. ontic

    ontic

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    Oh I wasn't talking about your solution, I was talking about Prutser's future one:lol3
    Seriously though, I am interested to see any solutions and how they turn out.

    I'm not sure how permanent a solution Rooney's version was. That is his race bike pictured.

    [​IMG]

    I might be wrong but I don't see it here
    [​IMG]
    [​IMG]

    I'm not sure what is going on on top of the airbox here, but it doesn't look like that pipe extension thing in the first photo
    [​IMG]

    I'll try to remember to ask Paul about it next time I talk to him.



    Yeah, that is one of the big concerns. I was thinking about how you'd do it with the tank version. Personally with tubes/filter through the tank I'd be wanting to be able to just remove the tank as normal without undoing any other hose clamps or anything annoying like that. I was thinking you could have a female rubber tube(s) going up from the airbox region to the tank and then a solid tapered male tube(s) going down from the tank that slides into the female tube and by clamping the tank down provides all the pressure and sealing surface required to make the pipe join air and water tight.

    I keep looking at my big alu Sauer tank and thinking of the possibilities for having a filter included inside the tank and still having a decent fuel capacity... I don't think I'd have the heart to butcher it yet though.
  14. Airhead Wrangler

    Airhead Wrangler Long timer

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    I have better photos than you :D:

    [​IMG]

    [​IMG]

    These are old photos though.
  15. bgoodsoil

    bgoodsoil Dare to be Stupid

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    Thanks for the pictures. He's still got an airbox even though there's a big hose running to it. Maybe as long as there's a box somewhere along the intake track you'll get the resonance effect?
  16. Plaka

    Plaka Brevis illi vita est

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    You get resonance where the tract has abrupt transitions. That's why the bellmouth horns inside the lower airbox, softens the transitions. The long tract up to the top will have it's own resonances.

    But considering what he's done with mufflers, he may not be too concerned with intake/exhaust tuning. it lower RPM you can indeed get away with blowing it off without giving up much. Not having the engine sucking unmeasured water and keeping the filter cleaner longer would be worth more.

    While the image of blasting through knee deep water may fire the manly imagination, in reality on a tour it's completely unlikely. Those slippery rocks under that water demand a more moderate approach lest you go swimming. On a sandy bottom you could get away with it...not common far from beaches( tho' I know one or two with shallow water).

    The bike will take heavy rain at speed without flooding the intake. The airflow under the tank is plenty "dirty". There is an air dam in front of the horns to help. (and keep oil cooler heat at bay, if fitted under the headstock.)

    Getting up out of the front wheel dust is a bigger factor but even that isn't a big one.

    Lay the bike down of course and it's all for nothing. Your best bet is a roll switch to kill the engine past a certain angle. Easy fabrication although the old thermostats with mercury switches in them are increasingly rare (in the states anyway). A deadman worn on one wrist is another simple solution.

    If you remove the airbox you can pivot the plastic tubes from the carbs to all sorts of angles and go from there. But they do support the carbs so a brace somewhere is wise. So you can bring a tube forward over the cylinders and terminate with a /5 style drum filter above the front of the tank. That also is a strait up fabrication. Another pair of plastic air tubes would be handy to make the final angle.

    Pressurizing carbs is very iffy. You need to balance pressure to the bowls so you get enough vacuum in the venturis to suck gas. Turbos that use carbs draw ambient pressure air through them, then compress it. If you want to blow through, use fuel injection that has pressurized fuel.

    There isn't anything low in the front cover that is water sensitive on a beancan ignition but the beancan plug. So that get sealed. There is also nothing to throw water around until you get up to the alternator. Use a brushless alternator (permanent magnet rotor) and it shouldn't mind getting wet. Bearings won't like the grit tho'. Ventilating the front cover is important to diode and alternator life.
  17. chollo9

    chollo9 Screwed the Pooch

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    Might want to check out some of the places Prutser has been!
  18. Airhead Wrangler

    Airhead Wrangler Long timer

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    ...at least in the US it is. Plenty of roads down here ford rivers, bridges wash out ALL the time, etc, etc. Prutser has ridden (and swam alongside) that bike all through Siberia which is notoriously wet and rivery, and I believe he's planning on taking it back there again.
  19. hardwaregrrl

    hardwaregrrl ignore list

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    Example A:


    [​IMG]

    And for the record, I like to play in Canada where the beavers don't give a damn about roads.:D No pun of course but have routinely been in knee deep water.
  20. naginalf

    naginalf Handy Schtroumpf

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    Well, when you live underneath sea level, on land reclaimed FROM the sea, I can understand a desire to be able to go through water. :D

    But seriously, my hat's off to anyone willing to brave the Russian wild on any motorcycle.