airbox to carb fitting

Discussion in 'Airheads' started by ritetwist, Feb 20, 2013.

  1. ritetwist

    ritetwist Been here awhile

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    Does the rubber hose connect the 45* plastic fitting to the airbox,or to the carb?
    I see Max shows the hose at the carb end but I realize this is just a schematic drawing.
    On bikes, I swear I have seen both ways.Is one correct or hook it up as best fit?
    Trying to make it right.
    Thanks.
    #1
  2. hardwaregrrl

    hardwaregrrl ignore list

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    Whatcha riding? But usually they connect the elbow to the airbox outlet.
    #2
  3. ritetwist

    ritetwist Been here awhile

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    1982 r65ls,sorry,I thought all of them would be the same?
    They sure can be fun to connect,esp. when new.
    #3
  4. Big Bamboo

    Big Bamboo Aircooled & Sunbaked

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    On both my R75/5 it's on the carb end.
    #4
  5. hardwaregrrl

    hardwaregrrl ignore list

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    <a href="http://s814.beta.photobucket.com/user/hardwaregrrl/media/bmw_r65_ls2_zps86f9821f.jpg.html" target="_blank"><img src="http://i814.photobucket.com/albums/zz66/hardwaregrrl/bmw_r65_ls2_zps86f9821f.jpg" border="0" alt=" photo bmw_r65_ls2_zps86f9821f.jpg"/></a>

    So rubber from elbow to airbox, elbow connects to back of carb, front of carb to head via rubber.
    #5
  6. ironjack63

    ironjack63 Adventurer

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    what kind of rubber is between carb and engine? Looks just like a piece of radiator hose. Can something from an auto parts place be used?
    #6
  7. ME 109

    ME 109 Long timer

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    It's such a crap fit up, it prolly doesn't matter where the rubber hose goes.:huh
    I once read there was a left and right side for the plastic elbow? I don't see much difference between them.

    Rubber needs to be fuel proof. Cheap enough to buy from aftermarket supplier, maybe even bmw
    #7
  8. disston

    disston ShadeTreeExpert

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    According to the parts fisch the rubber part goes on the carb side of the suction funnel (that's what they call it);

    [​IMG]

    There is also a right side and a left side of the plastic elbow. I don't have mine put together like the picture either. The rubber tube I have has an internal step and fits the air box to plastic suction funnel better. The connection to the carb doesn't need any rubber on mine anyway.

    These parts are put together numerous different ways. The idea is to seal out dirt on the airbox side and to seal in the vacuum on the head intake side.

    I have proposed using radiator hose for the rubber parts but many have objected and said the anti freeze resistant radiator hose may not be gasohol resistant. Maybe. But in a pinch it might work for some time before a proper material can be found.
    #8
  9. disston

    disston ShadeTreeExpert

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    Sorry. I posted the fisch of my bike and of course it has nothing to do with a more modern piece of art such as the R65ls such as yours.

    [​IMG]

    The suction funnels appear to be on the inside of the box. They are right and left side parts. #14 is called a pipe. And the plastic elbows are the same on both sides, not different like on us older bikers, er, bikes.

    The rubber grommet is still on the carb side at least in the picture.

    That's not clear to me at all because I don't have one of these. Is my impression correct about the tubes inside the air box, are they different tubes inside the box? And the same on the out side?

    You can't always depend on the micro fisch picture being correct in details.
    #9
  10. chollo9

    chollo9 Screwed the Pooch

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    I was relatively ignorant when I had my R75/5. I had only the plastic tubes and two clamps per side between the carbs and the airbox. They never really fit right (just a leetle beet too short) and I always cursed them. Is it only now that I'm finding out the source of my frustration? Or were there two different versions of tubes?
    #10
  11. supershaft

    supershaft because I can

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    So I hope everyone figured out it depends on the model per the ETK.

    I think the square airbox snorkels are much easier to deal with than the clam shell snorkels. I always custom grind on the late model setups and get them fitting perfectly. Easy on and off. Just lower the radiator hose at the airbox and off they come. A lot of them will never fit close to right for the carb/head radiator hose being too long. That includes the clam shell types and the square airbox types.
    #11
  12. craydds

    craydds Long timer

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    I have a '75 R90S with Dellortos so my airtubes are easy on and easy off (with my TOP SECRET modifications).
    #12
  13. craydds

    craydds Long timer

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    Are you sharing my TOP SECRET modifications? Great! Free to all - who run Dell's.
    #13
  14. supershaft

    supershaft because I can

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    Same here with my Dellorto's on my '92 RT but it isn't secret. I used the velocity stack threads on my Dellorto's as a depth gauge to file off about one third of the threads and keep the carb mouth perfectly round. I then put my RT's stock snorkels on my Dell's just like they were Bings. I have had more than a couple of people in the know tell me it was about the cleanest Dellorto setup they had ever seen. The setup looks exactly like the R65 up above but with Dellorto's instead of Bings. Well, that and different carb spigots but they have the same rubber hose style mount as Bings. Rigid mounted carbs was old fashion in '74! I was sure to get rubber mounted ones.
    #14
  15. craydds

    craydds Long timer

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    Very cool! I also grind off the plastics numbs/bumps - what ever you call them - on the airtubes so the rubber rings slip on/off with ease. This may apply to Bings, too - I will look at my '74 R90/6. Will make some pics if that will help fellow inmates.
    #15
  16. ritetwist

    ritetwist Been here awhile

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    I bought a 1' chunk of H2O discharge hose from our hose supplier.2" I.D. pliable can easily be slipped over
    carb and airbox tubes.$7.00 for a foot.As opposed to $7.30 for one piece from BMW.
    Rated for water but since it is not soaking in gas may last a while.Worth a try anyway.
    Thanks for all the input.
    #16
  17. craydds

    craydds Long timer

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    :ear:
    #17
  18. mkdauff

    mkdauff Idiot Savant

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    Has anyone ever used any of the silicone tubing for these intake-to-carb elbows before? Blue is what you would see on the front-mounted intercoolers of the rice-burners of the early 2000's, but if a proper bend and diameter could be found to fit this use I think it'd function and look great (in black).

    I think this would be fuel resistant, but am uncertain...

    Here's a site for reference:

    http://www.siliconeintakes.com/
    #18
  19. disston

    disston ShadeTreeExpert

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    Should be gas and oil and heat resistant. I looked at the Web page and did not see anything about what chemicals their products are resistant to.

    This came up before and the stuff sold that time was for compressors and blowers used on race cars. All of it was fancy looking stuff that was not resistant to fuel mists. I wrote them and asked. They said that their products would last for awhile but was not specifically meant to be used on the link that had fuel mists in it. On the Airhead it may last longer on the filter side but not long at all on the head side.

    Write to them and ask if their stuff resists Gasohol, Oil and Heat (to what temp?). Then maybe you will be the first.

    If somebody was to make a product specifically for Airhead applications and it was made to last I think it would sell nicely. (price dependent of course)
    #19
  20. supershaft

    supershaft because I can

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    Radiator hose works perfectly. I have used it for decades as have many others I know. Same diff as the BMW stuff.
    #20