My mongoose beast project

Discussion in 'Motorized Bicycle General Discussion' started by felix2, Sep 18, 2013.

  1. felix2

    felix2 New Member

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    Hi!
    So I snagged one of these with the intention of just putting ape hangers on it. it actually rides pretty smooth and was plenty happy with it at first. Then of course my modification side took over and putting a little motor on it was the best idea ever. Its been slow going as I dont have tons of free time, but it's mega fun to work at it.

    Right now, i'm working at realigning the chain and rear sprocket because it seems the sprocket keeps 'walking' off the chain at random. Also, tuning the CNS carb. I may put the original kit carb on just for break in and to shake out other kinks first. So far, no riding yet though. I also want to better mount the carb as i had to swing it out to the side for clearance. Used a thick hose to do that, need to stop by the store for a thicker diameter one.

    Its real rough right now. I need to clean up wires and cables and hide my crappy welds, but it's sparked to life and i'm enjoying the project. Thanks to you guys for the helpful threads!
     
    #1 felix2, Sep 18, 2013
    Last edited: Apr 2, 2014
  2. felix2

    felix2 New Member

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    Flintstone brakes at the moment...lol
     
  3. maniac57

    maniac57 Old, Fat, and still faster than you

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    If your engine is not mounted securely front and rear, your chain will never be reliable.
    From the look of the picture, you have it mounted only at the front. Find some way to secure the rear mount and your chain will be more reliable, not to mention several other possible problems if (when) the front mount breaks.
    I hope I'm looking wrong. I love the idea, but the engine needs to be bolted in better from what I see.
     
  4. mapbike

    mapbike Active Member

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    As wide as that rear tire is I see no way you will ever have proper chain alignment unless the engine is offset 3/4"-1" from centerline of frames down tube, if it is twisted any at all you will never keep a chain on it, if this has been done and I can see it in the pic then disreguard this part of this post.

    The intake in the link I posted below along with either the RT carb that Dax sells or even a standard NT kit carb will like ly solve the carb clearance issue you have going on there.

    If you are using a super long rubber hose for an intake chances are you will never get the carb acting right.

    http://www.jnmotorsbikes.com/product_p/jnm1171.htm

    Map
    reddd
     
  5. Dan

    Dan Staff
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    Awesome looking build, Felix. The ape hangers really set her off.

    Scared the tare out of me. "Flintstone brakes" Bet that ain't real fun.

    She has a sort of Moon Buggy, hard core motorized bicycle sort of look. Very cool.
     
    #5 Dan, Sep 19, 2013
    Last edited: Sep 19, 2013
  6. felix2

    felix2 New Member

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    Thanks guys for the compliments and suggestions.

    I have actually offset the motor about an inch if I remember. I welded a section of tube perpendicular to the downtube for the front mount and for the rear I did the same just off to the side of the crank housing tube. I'll post a picture looking over the top.
     
  7. felix2

    felix2 New Member

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    Gonna space the sprocket on the wheel over a bit next and it should be ready for a ride. Oh ya and choke wire needs to be redone now that i look at it. It snapped out earlier..
     

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  8. Dan

    Dan Staff
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    Really coming out suweet. Amazing symmetry.

    Looking at your first picture again, I keep seeing a layback seat post and a shorty chrome and flared rear fender.

    Not at all a suggestion, ya just got me thinking. One of those bikes is on my "some day list"



    Please, please do get brakes before a real shake-down cruise, though. Would hate to read about you in the motorized bicycles in the news thread!
     
  9. dodge dude94

    dodge dude94 New Member

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    Is that a missing seatpost I see there?

    Kudos for doing something others have thought about, but have not done. I just hope you can get the safety stuff worked out before you ride it.
     
  10. felix2

    felix2 New Member

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    Definitely Dan.
    Moving the seat post or mount back somehow while keeping it low is in my list to do. I'm working on snagging a fender from a friend. He says it has a long sweeping look to it, I haven't seen it yet. A fender is needed though cuz sitting that low, my shirt rubs the tire...then i have a skid mark, unless i tuck my shirt in. I'm glad you enjoy it. I'm really digging this site and your guys' threads.

    This project has made me appreciate the engineering that goes into more complex builds and bikes. I also have a kawasaki ninja zx6r, but these 2 stroke bikes are almost more fun!
     
  11. felix2

    felix2 New Member

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    dodge dude, yes i cut the seat tube out all the way to make room, then cut a piece off of it and used that to make the front mount. i used the left over tube to make the rear post mount. eventually i think i'll have to tie in that off center post in the rear that i welded back into the point up top where i cut it out...if that makes sense, for structual integrity. either that or put some gussets some where.
     
  12. Dan

    Dan Staff
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    Awesome Felix.

    Ayup, some days, the sitting, thinking, staring and tinkering is even more fun then riding. (some days, snork)
     
  13. dodge dude94

    dodge dude94 New Member

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    I think you should gusset that triangle. We know these china bikes aren't the best quality, I'd had to see you blow the frame at 15mph. Or however fast this thing will go with those ginormous tires.
     
  14. felix2

    felix2 New Member

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    first shake down flintstone run was crazy fun! had to be some where around 20-25 mph. will definitely gusset that frame somewhere if i dont add another tube cross member type structure.

    the chain rubs the tire a bit, but thats ok with me..for now. it was a night/dusk ride and the looks on peoples and kids faces was great.

    it's plenty fast for me cuz i just basically want a lazy cruiser, but i probably will try to adjust performance to smooth it out a bit. also, it doesnt idle well but i haven't adjusted the nt carb yet. i'm in the process of searching that now.

    thanks guys, couldnt do this without all of your threads on this site. i'm stoked.
     
  15. mapbike

    mapbike Active Member

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    I'm looking forward to seeing it come along as you work to get it just the way you want it...... That is a unique build for sure...... I tell people all the time to keep the rubber side down, but for you I'm gonna say keep the rubber side down X2 cause there is at least twice as much rubber on that bike than there is on a normal one.....

    Them there is some tires and evafang....!

    Map
    reddd
     
  16. mapbike

    mapbike Active Member

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    Let me get this straight with the number thing you mentioned...


    Wuan, Q, Tree, Fo, Fy, Siks, Sem, ate, Ni, Tin....

    Ok yeah I got it...LOL!

    Map
    reddd
     
  17. Krealitygroup

    Krealitygroup New Member

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    Man! My hats off to you. This was a project I wanted to do, but lost confidence. You killed it. I'd off road that bike to heck..
     
  18. Dan

    Dan Staff
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    LOL map

    Wuan, Q, Tree, Fo, Fy, Siks, Sem, ate, Ni, Tin.."

    took me a while
     
    #18 Dan, Sep 20, 2013
    Last edited: Sep 20, 2013

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