GIANT boulder with EHO35 GEBE drive

Discussion in 'Photos & Bicycle Builds' started by Wheres my dog, Mar 30, 2010.

  1. Wheres my dog

    Wheres my dog New Member

    A thread in the works here as I finish building her . . . . .

    The bike is a GIANT boulder XL bought from a local bike shop with extras for $419

    The engine is a Subaru EHO35 bought brand new on this site here for $163

    The engine mounting and drive kit is from GEBE and was purchased for $350

    The (more on this later) extra long 10mm x 187mm x 26tpi axle was bought for $11.99

    Total build price at this point is $943.99 and to say the least, I am way over budget on this build! BUT, all components are high quality and I value them for the many years of use they are going to give me.

    First problem:

    At first measurement, the GIANT seemed to have enough clearence for the drivering on the rear wheel. Upon installing, the drivering was taunt against the left lower stay. My idea was to shim the axle between the left lower stay and the hub... but with the locknuts already hanging off by 3 threads, I knew I would need a longer axle.

    Just got back from picking up the new 187mm axle and it seems to be a good 3/8" longer then the original. This will easy allow me to fit in a flat washer or two and bump out the left side and get those locknuts on all the way.

    Either going to work on it tonight, or first thing tomorrow morning....

    More to come tomorrow on this post, as well as pictures!

  2. seanhan

    seanhan Member

    Sounds Good dog

    gebe says to use a credit card to measure for clearence.
    did you put the belt around the ring and check for belt clearence.
    mine hit the rear brakes and i had to tilt the gebe rig backwards a little bit till it cleared .... Hey one thing you really need to do for extra measure of safety is get a heavy duty tie wrap, and fasten it to the front mount strap in one of the empty holes and also around bike frame.

    What that does is if your front mount strap bolts fall out or the strap breaks it will keep the enging from falling back and giving you full throttle and unpluging your kill switch at the same time. That would be a real bummer.

    Hey my bolt did come loose .. Now I check it often...
    but 1 tie wrap can save your butt.....:jester:
  3. Wheres my dog

    Wheres my dog New Member


    That was also an issue with mine as well... I was hoping for the engine to sit closer to the back of the seat, but because those brake arms are so huge, I had to poush the engine back some to get the belt away from the brakes.

    Point taken, I will zip tie it as well to the bottom of the seat post. I have the strap bolted thru the frame just below the seatpost with a grade 8 bolt and nylon locking nut as well. I will check it, but I do not see it coming lose or breaking as it is grade 8.

    Going to work on it right now..... more to come!
  4. seanhan

    seanhan Member

    It wont hurt

    To have the engine leaned back a little bit..
    hasen't have any adverse reaction on mine.
  5. Wheres my dog

    Wheres my dog New Member

    Pictures coming later tonight or tomorrow...

    She is all done and happy to say fully tested out where I know I am reasonably safe with riding her some distances!

    The engine is purring like a kitten, and has a good amount of power and torque for 35cc's. When I hit the magic number of 18 or 19 miles per hour, she really seems to humm along and disappear with the breeze.

    The drivering snapped nicely onto the back wheel, and needed to be "adjusted" about a 1/16th of an inch to be centered on the wheel. The belt is snuggly attached and is showing no signs of wear at all with about ~40 or so miles on it.

    My only standing concern, if you can call it that, is because of the large brake arms on the back wheel, I had to tilt the engine further back on the wheel then I would of liked to. The only downfall to this is the gas tank is now leaning back, and when "filled", is only about 65% full in volume. My thoughts to this would be to either go with a disc brake if possible on the rear, or remove the tank from the engine, and fab up a new tank somewhere near the engine to hold at least 24 ounces or better.

    On a (engine leaning back) full tank of fuel, I am getting roughly 13 miles to the tank with the standard GEBE gear.

    On an open flat road today with no traffic to scare me, I topped out at 26.6mph with said standard gear!

    Before riding the bike, I did some measurements with my SUV speedometer and my GPS on my cell phone, and after testing the bike, she is very near 100% accurate with speeds and distances on the bicycle speedometer.

    I have built a few MB's over the years now, and hands down, this is the BEST bicycle, and the BEST engine, and the best (GEBE) setup I have ever had period! It works well, and I can say I have full confidence in the components and the bicycle shop who built the bike for me.

    Standing thoughts at this point.....

    Either mount a new fuel tank somewhere close to the existing one, or leave that one alone, and I was thinking of mounting a bottle holder onto the vertical GEBE strap and carrying a ~32 ounce MSR fuel bottle for distance riding, as not having to stop at a gas station every 13 miles or so!

    The seat as thought, has to be changed out to a larger more comfortable seat while riding. It seems to be ok for shorter trips, but over 10 miles, it just hurts a little too much.

    Need to order a spare belt to keep on the bike at all times, and thinking of ordering the trail gear to see what extra power it offers on the steeper hills.

    Searching for a extra heavy duty locking device for the bike if left alone in public while eating or such.

    As mentioned earlier, I will post pics tonight or tomorrow!
  6. vegaspaddy

    vegaspaddy Member

    hi wmd,

    isnt the gebe kit a beaut, reliable been the key word, i have a tanaka 33 setup, the cool thing about the 2 stroke is that you can turn the engine 90 degrees so there is never an issue with tight spaces.....

    There have been alot of mods with people adding a secondary tank for extra milage this would probably be the most effective way to go.

    Extra belt is always a comfort and if you havnt thought about it a permanent mount to the bike makes the kit feel like it belongs there, as well as been alot easier to get the rear wheel on and off .......

    pics already !!!!!!!!!
    Last edited: Apr 14, 2010
  7. seanhan

    seanhan Member


    Leave your old tank on and do the 2 tank cascade system. Staton inc. has some nice AUX tanks for a fair price.
    isn't that GEBE smooth......................
  8. Wheres my dog

    Wheres my dog New Member

    I love the GEBE setup..... smooth as all he** as they say!

    Just need more fuel capacity and I have a serious distance bike in my midst!

    Pics coming very soon
  9. seanhan

    seanhan Member

    Here is a old Pic of my GEBE

    Notice the engine tilt back to let belt clear brake arm.

    Attached Files:

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  10. Wheres my dog

    Wheres my dog New Member

    Yeah yeah yeah, lucky you with the two stroke engine set 90 degrees off and you have the whole tank to fill with fuel..... you lucky dog!