GEBE Tanaka 40cc, burning my ***

Discussion in 'Rack Mounted Engines' started by hawaiioutdoors, Mar 29, 2009.

  1. hawaiioutdoors

    hawaiioutdoors New Member

    :helmet:To all you GEBE Gurus,
    I installed a GEBE Tanaka 40cc on my Yeti DH-9, I had the Tanaka tucked up under the bicycle seat. Trying to get the weight as close to center as possible. I test rode the bike, and the exhaust was close to my right thigh, and my *** kept hitting the spark-plug....
    I noticed on some bikes on this forum, the Tanaka's are set up vertical, with the tank standing up and down. This puts the exhaust straight down, which would be great.
    What bolts are removed to do this ? The bolts from the engine to the mount, or from the engine to the gear-drive unit.
    Is there any ill effects to the the carburator not working properlyl?
    Last edited by a moderator: Mar 29, 2009

  2. srdavo

    srdavo Active Member

    I moved this thread to the rack-mount forum.....PLEASE...Do NOT try to dance around our auto censor.

    Include pics of you bike & kit install to better explain your problem.
    Last edited: Mar 29, 2009
  3. Zev0

    Zev0 Member

    Engine to the mount. Actually, we've found that it seems to run better in that position. Plus easier to start while seated.
  4. hawaiioutdoors

    hawaiioutdoors New Member

    I moved this thread to the rack-mount forum.....PLEASE...Do NOT try to dance around our auto censor.

    Sorry super moderator,
    I was not trying to offend anyone, I was trying to say my right buttocks, kept making contact with the top of the engine while riding on gravel roads...

    How do I get the horizontal tank converted to a vertical tank configuration?
  5. bamabikeguy

    bamabikeguy Active Member

    If you want to turn the engine 90 degrees, you have to buy this Craftsman socket, available at Sears, about $6. (pic #1).

    However, optimum performance is achieved straight up from the axle. (#2).

    I'm not sure if what you are talking about on that gas tank configuration isn't taken from a pre-2007 thread, the old Zenoah's and Tanaka's had a drive shaft that held the belt gear, then you could slide the engine over the shaft and could turn it one way or the other before tightening it to the mount (#3).

    As to wanting to have the engine closer to you on the seat, I've been doing the opposite, trying to push it farther back, in order to gain some room in that space for saddlebags or rack set-ups. (#4).

    Attached Files:

  6. bamabikeguy

    bamabikeguy Active Member

    I think this is the kind of set up that confuses the situation, that is a pre-2007 build, and there are a few more that look like it...

    Attached Files:

  7. Hive

    Hive Guest

    Tanaka Engine Position - Vertical vs Horizontal

    Sorry, I have been off the site lately, and I see now it is getting slow...but

    A search might have turned this up this link:

    You DO want the engine vertical. No explanation why GEBE sends some out horizontal.

    No-brainer. You need a suitable sized metric hex set, as I recall and maybe metric end spanner/wrench/sockets, as noted above. It is easy to turn the clutch/gear box 90 degrees. You will figure it out, if you look at it awhile.

    You will have to lengthen the intake fuel line, so it goes to the bottom. Two-cycles prefer not to run out of gas; riders like to use all the gas possible to limit refuel frequency.

    Easy, really, but be careful, the tank studs have sleeves than can be lost when you pull tank, and make sure all tight when finished.

    The nice thing about the 2-cycle engine is no oil filler/dip-stick port to worry about.
    Last edited by a moderator: Apr 1, 2009
  8. seanhan

    seanhan Member

    Move that GEBE back a Little.
    mine is actully a little bit past vertical.
    Just make you front strap a little longer and lean that puppy back.
    Then secure the front strap. and walla !!!!!
    Yea man you dont want that thing up your A@# !!!!!
    It will ballance the bike just fine in almost any position...
    Double check belt clearence before startup...
  9. Hive

    Hive Guest

    Engien Position

    I have to raise a word of caution here.

    Any addition of weight to the center of balance will have minimal change to the gyro stability of the bike. but it will change it, particularly when moving off the straight line.

    The further additional weight extends from the COB, the less stable the gyro effect, particularly on direction change.

    In fact, if you use shock forks, the rig may become unwieldy at speed, particularly on changing direction quickly and create unsafe conditions...that could cause lose of control...

    The closer the engine can be placed to rider, more stable the ride, though less stable than if there was no motor.

    And, esthetically, it certainly looks better.
    Last edited by a moderator: Apr 1, 2009
  10. augidog

    augidog New Member

    Last edited: Apr 7, 2009
  11. hawaiioutdoors

    hawaiioutdoors New Member

    Rotating Tanaka so Gas tank is vertical Post # 18

    Thats what I am looking for.!!!! Thanks for the link:idea::idea:

    Rotating the 2 stroke Tanaka would get the exhaust away from my thigh,
    plus, get the Gas tank vertical so that I can fill it up all the way...:grin5:

  12. michael m

    michael m New Member

    A tanaka 40 cc will run upside down:rolleyes7:
  13. GearNut

    GearNut Active Member

    Any 2 stroke can run upside down. Or forwards, or backwards, or diagonal, or on it's side. If it is set up with a diaphragm carburetor they really do not care one way or the other.
    Now....... the fuel tank and placement of the fuel pick up will care, very much so.
  14. JemmaUK

    JemmaUK Guest

    To be brutally honest it makes not the slightest bit of difference...

    The biggest part of the weight of the bike is the rider - thats the thing that makes the most difference to slow speed handling. To be frank if you cant handle a bicycle at slow speed then what are you doing trying to ride one at 35mph?

    I have done over 2000 miles on my bike and I have had not one problem with slow speed handling - the only fall I had was a flat out fall in the wet when I hit the front brake first and it dropped on me... my own fault.

    In any case for the engine and such to adjust the handling you would have to drop the engine down in front of the crank and underneath - which would actually make a difference to centre of gravity... this is the same reason that you would angle a 4-pot engine at 45 degrees in a sports model, where it would sit vertically in a family saloon. its merely to make the bonnet line lower, the moment of balance lower down therefore making the handling more lively and accurate.

    Jemma xx