79cc vs 212cc Predator

Discussion in '4 Stroke Bicycle Engines & Kits' started by ultralight01, Dec 2, 2016.

  1. ultralight01

    ultralight01 New Member

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    So I'm about to build a new bike. I did build a china girl kit bike as you may or may not remember, but now I want something more reliable.
    I want to go with a predator, since I have experience with these engines from building go karts. I have a lot of experience with the 212, but I've never touched a 79cc. Sounds like weak crap for a go kart, but for a bicycle it seems like plenty.

    I already have a 212cc that I got from Necromancer. I'm in the middle of taking out the clip that holds the governor on and it's droving me nuts, but what the heck. I'll get it out.

    The next bike that I want to build will be an enduro-type thing. I have a schwinn sierra frame (Thanks again Necromancer) that I'm planning to put a crf50 seat, plastics, and tank on. No rear suspension, mountain bike front fork, and beefed up components in general. Should be fun to jump and do some light off roading with.

    I'm scared of a 212 on a bicycle though. I keep asking myself, Is this thing too heavy? To powerful? To hard to pass by the cops?

    Should I just get a 79cc?

    I'd appreciate any opinions. Thank you .shft.
     
  2. Venice Motor Bikes

    Venice Motor Bikes Custom Builder / Dealer/Los Angeles

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    A 49cc 4-stroke kit is inexpensive, extremely reliable (& very easy to put together). ;)

    I like the 7G kits.

    If your heart is set on a 79 vs 212 engine?, I'd go with the 212. (^)
     
  3. Tony01

    Tony01 Member

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    Fixed for you.

    212 not hard to pass by cops at all. Just floor it and lose him on a bike path or park.
     
  4. ultralight01

    ultralight01 New Member

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    Haha tony. So what should I do... argh. No real opinions except go with the 212 for no given reason
     
  5. culvercityclassic

    culvercityclassic Well-Known Member

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    I like the 212, it must be built well tho, do it right spend the money on brakes and drive system. The 79cc and 99cc are a disappointment power wise, that's because I started with the 200cc and then back tracked to the 99cc...
     
  6. ultralight01

    ultralight01 New Member

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    So it is heavy or scary or anything like that? Too wide?
     
  7. culvercityclassic

    culvercityclassic Well-Known Member

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    It's big, it's heavy, it's wide but it's fun... better to have the power and not need it than to to want the power and hot have it...Build It!!!!
     
  8. ultralight01

    ultralight01 New Member

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    Done. 212 it is. I'll probably use it more off road than on road.
     
  9. Tony01

    Tony01 Member

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    Dude 212 is loads of fun. mine is my daily driver. I ride it rain or shine. Apart from a removed governor it's bone stock. The head has some sharp corners in it that I'll smooth out when I make some upgrades. I'm planning easy stuff, shave head and install ratio rockers.

    The shroud and fan make it wide. I removed both and cut down the starter cup and make it a rope start. Takes off like 3".
     
    #9 Tony01, Dec 3, 2016
    Last edited: Jan 5, 2017
  10. ultralight01

    ultralight01 New Member

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    So the engine is fine with no fan? And you just keep a rope in your pocket or something to start it?
    I'm also wondering what kind of mileage I'll get with a .7 gallon tank.
     
    #10 ultralight01, Dec 3, 2016
    Last edited: Dec 3, 2016
  11. curtisfox

    curtisfox Active Member

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    This is really looking good, got to watch it closer. .............Curt
     
  12. ajoh

    ajoh Member

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    ultralight find threads by guys like "scotto" who've built 212's an get tips an tricks from their builds eg, from memory this is the rear hub scotto uses (only from another dealer)
    http://www.bikeberry.com/engine-kit...uning-non-free-wheel-heavy-duty-axle-kit.html

    then he uses a jackshaft disc brake, he cuts the disc down to detune it so it's not so sensitive

    pretty sure he swears by frames built by felt too, for there strength ? (honestly can't remember whether i correct with that or not as it's been a while lol)

    just be safe an have fun..........oh an good luck...........
     
  13. MotoMagz

    MotoMagz Active Member

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    Yes it is big but like mentioned above you can shrink it a little. I did do a lot of stuff internally and externally on my motor so I can not comment on a stock motor. If you remove govoner you want a billet fly wheel For sure. I chose a ultalite with 6 degree advance timing built right in. Nexts 18 lb springs and then a long intake with a Real Mikuni Vm22 carb.Which let me to a header pipe with. Rlv free flow muffler. It's drive is a cut to a WHIZZER rear sheave all belt drive. It is unbelievable how much torque it has. If you can do it go with the 212cc if not start of with a kit like 7g. 212 is not a bolt and go it's more of a project with some small welds in most cases...good luck
     

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  14. ultralight01

    ultralight01 New Member

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    Motomags, if you do not have a billet Conrod, prepare to lose your balls (Not really, it's mounted vertically. Haha)
    I had a lightly modified clone that exploded with a billet flywheel but a stock Conrod.
     
  15. Tony01

    Tony01 Member

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    You don't need billet parts unless you plan on turning high rpms. Stock 212 gov removed predator single speed runs good with a gear ratio of 6.5 to 8.2. I'm running a 7:1 right now and my buddy runs an 8:1. His revs out more but our top speeds are still about the same at 55ish. Gear it for the rpms so you don't overrev it.
     
  16. MotoMagz

    MotoMagz Active Member

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    Ya I'm cool with the cvt I don't push high revs....cuz
    I like my balls
     
  17. donphantasmo

    donphantasmo New Member

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    My buddy has a mini bike and we just went from a 79cc to the 212... I'll tell you there is a HUUUGGGEEEE difference.

    I can't believe I'm about to say this, but the 79cc was plenty. The 212 is too much for a bicycle. Don't forget that the bike's bearings and brakes were meant for pedaling. So, if you upgrade it to a 79cc, you're pushing it's limits. If you go with the 212, you better make sure it's a damn good bike, and it can handle the power.

    Let's just put it this way... I have (and sold many) classic Vespas. these things are 90cc, 125cc and 150cc. The newest one (the PX150) has about 7-8 HP and goes about 55-57MPH. A Vespa weighs a lot more than a bicycle with a motor. And it doesn't have the HP the predator 212 has... So, be careful, or you'll break most speed limits, and most bones..

    Like I said, honestly the 79cc was PLENTY of power for me.

    Best of luck either way.
     
  18. ultralight01

    ultralight01 New Member

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    If you guys have been keeping up with my other thread, I bought a 79cc and now I'm modifying it. Governor is gone, new exhaust and 3D printed air intake adapter. I, saving my 212 for a diy surf winch. Why buy one for $2000 when I could build one for a few hundred bucks and some work/welding?
     
  19. Scott.D.Lang

    Scott.D.Lang Member

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    Not that my 2 cents matter but since you have 212 stuff Id go with the 212 but from someone that has built a few 79ccs they have enough power to go 50 plus stock with governor removal. and easly quicker then any 2 stroke build not as fast top end but quicker.
    I am starting on a 212 build now but the only reason Im running a 212 is because I wanted to use a 3d clutch.
     
  20. TheNecromancer13

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    If you geared a 79 to go 50 mph it would have crap acceleration power.
     

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