What kind of mountain bike for a bicycle engine?

Discussion in 'Motorized Bicycle General Discussion' started by INRI, Jan 9, 2008.

  1. INRI

    INRI New Member

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    Hello,
    I am looking at buying a used mountain bike 26" for use with a bike engine kit. Now, I have noticed some riders here have what I deem as an older/unique bike style that they mount the bike engine kit to. I really enjoy the looks of a mountain bike and wanted to know if anyone had any information to share about a mountain bike brand ex. Trek/cannondale that they felt comfortable with and enjoyed riding with a bike engine kit.
    Thanks for your help
     
  2. Bikeguy Joe

    Bikeguy Joe Godfather of Motorized Bicycles

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    Re: What kind of mountain bike for a bike engine?

    I'll add the obvious....look for one with or without rear suspension that you can still fit the engine within the frame. Also, if you plan on using it for off road, you may want to look for a beefy frame (compare) and use one of the 46 or 48 tooth sprockets for more low end grunt.

    These engines will haul a lot of weight so don't be overly concerned with the total weight of the bike/rider.
     
  3. INRI

    INRI New Member

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    Re: What kind of mountain bike for a bike engine?

    Thanks for the reply.
    Yes I am tall and shall I say "average weight for my 6'6 frame. I am 250 pounds, so I like and look "normal" on a beefy mountain bike. I know that most of the beefy frames are rather large and would wonder if the engine would be able to fit and work with a larger frame. I spoke with a dealer not to long ago and he told me that some bike engines have a hard time bolting to larger diameter frames. I was unaware that a 46-48 tooth sprocket could give more low end. With my weight I would need it. Thanks for your post!
     
  4. Bikeguy Joe

    Bikeguy Joe Godfather of Motorized Bicycles

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    Re: What kind of mountain bike for a bike engine?

    Mounting to the larger diameter frame tubing is pretty simple...there are several ways to do it. Some drill holes and use longer studs, some mount with an exhaust mount. You bolt that to the engine, then use a couple of heavy duty muffler or hose clamps to connect that to the frame. I'll dig that part out and get a part number for anyone intetrested in that mounting technique.

    As for the sprockets, I have a couple of them if any one is interested. I don't remember if they are 46 or 48 tooth, but any one interested can PM me and I'll dig 'em out and count the teeth and we can talk price (nearly free+shipping) then.
     
    #4 Bikeguy Joe, Jan 11, 2008
    Last edited: Jan 11, 2008
  5. paul

    paul Active Member

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    Re: What kind of mountain bike for a bike engine?

    i weigh about 210lbs and ride real hard. i have never had a problem with any frame unless i crash. i have had probably 20 mountain bikes over the years. personally for my motor bicycle i wanted a chromoly frame. they are very strong and most of your inexpensive bikes are made with it.
     
  6. Andyinchville1

    Andyinchville1 Manufacturer/Dealer

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    Re: What kind of mountain bike for a bike engine?

    HI,

    For ease of installation I like a slightly large frame (size wise) made from with the standard size tubes.....Mountain bikes fitting this description are harder to find....seems like everything has gone to over sized tubing and/or rear suspensions that always have the shock in the place where the engine needs to mount to (assuming a center mount happy time type engine).

    I have sold a few bikes locally to people and for cost / ease of availability reasons I have been using the silver Road Master mountain bike they sell at Wal Mart for about $60.....This is definitely not a high quality bike but it seems that most of the local buyers here stress low price over anything else....At least I hope until they get bitten by the mortorized bicycling bug!.

    This frame is the exact opposite of easy installs (small tight fit requiring shaving of the air filter housing, denting the frame so the factory front engine studs straddle the down tube (not enough room to use the oversize tubing frame adaptor) etc....but it does
    look nice and the bike is definitely priced low.

    My personal bikes are Specialized Rock Hopper and a Trek 7000....Both mountain bikes.

    Good Luck and have fun!

    Andrew
     
  7. Norman

    Norman LORD VADER Moderator
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    Re: What kind of mountain bike for a bike engine?

    [​IMG]How about a Wally world schwinn. I don't like to mount the engine by drilling the frame sometimes you just about have to and on this bike I had to make a different intake manifold.[​IMG]
     
  8. Andyinchville1

    Andyinchville1 Manufacturer/Dealer

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    Re: What kind of mountain bike for a bike engine?

    Nice install.....I didn't thing the engine would get in there but apparently it does!
    Andrew

    PS - I like the "shorty" manifold....Does it seem to run any differently than the stock
    manifold?
     
  9. Norman

    Norman LORD VADER Moderator
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    Re: What kind of mountain bike for a bike engine?

    Andy
    It is a very tight squeeze and I did make the manifold which was easy enough. I also did some grinding on the air cleaner(shaved off the teeth on the bottom) and changed out the float bowl(Dax engine) this carb had a drain on the float so I swapped out with another one off one of my bikes. I also had to use the dremel on the clutch cable mount trimmed it to clear the float bowl. And I drilled the frame for the front mount:-||. The exhaust is also bent a little to clear the frame. O yes I massaged the rear frame where the top chain run is. A hammer and brass punch and a beating fixed that. I also had to change out the brake, derailler front and rear derailler cables. They were on the top frame rail. last was different straps to mount the fuel tank.
    Performance wise no change found using a short manifold all tho this bike isn't broke in yet. I plan on selling it so some lucky person that just has to have one. I've had a bunch want it but no ones came up wit the cash yet.
     
  10. Ilikeabikea

    Ilikeabikea Moderator
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    Re: What kind of mountain bike for a bike engine?

    Hey Norm, I have a bike that looks almost exactly like that one. Mine has a cooler looking bend in the exhaust though. Teresa still ain't rode it though. Maybe after this snow melts......................
     

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  11. frank osborn

    frank osborn New Member

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    Hi Andrew, I have just ordered a 70cc kit and wanted to use it on a Specialized Rock Hopper that I have. I am wondering if it has a big enough frame to fit it in?
     
  12. paul

    paul Active Member

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    yes it will fit fine. i was looking at one and it will make a great motorized bicycle. i had a rock hopper long ago and it was a nice ride
     

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