6.5 predator and cruiser bike

Discussion in 'General Questions' started by ronphelps, Jan 9, 2013.

  1. ronphelps

    ronphelps New Member

    Hello, Anyone out there ever put a 6.5 predator engine on a swhinn cruiser bike and what would be the modifications needed thanks Here is a picture of the one I am thinking of changing P1030323.jpg P1030320.jpg

  2. Richard H.

    Richard H. Member

    You mean the 200+cc ehgine that weighs 38 lbs? I'd recommend a motorcycle frame.
  3. EZMJon

    EZMJon Member

    I would be careful. Putting a motor that size on a bike is not safe and I really wouldn't recommend it. I have the Predator 79cc motor I am using in a build right now. I got mine from Harbor Freight for about $100. Keep in mind, It's a very low RPM motor. About 3500rpm MAX! So gearing it correctly is a must. Good luck with your build, but maybe rethink using that motor. Ill Post a "how to" on getting the 79cc Predator Engine ready for use on a motorbike once I have finished with building my bike. Hope this helps some.
    wacogerald likes this.
  4. ronphelps

    ronphelps New Member

    OK, Thanks for the info. I will rethink the motor exchange, possibly a larger frame bike, but the idea is to still have pedals and still call it a bicycle with a "motor" may not be legal but will not raise a lot of flags. Look forward to your next bujld on forum Bye.
  5. professor

    professor Active Member

    I did build a 212 predator, there are a few of these builds on the motorbike sites.

    I found they vibrate unbelievably, so much so I had to use isolators to kill the vibes as much as possible. I don't know how the other guys deal with it.

    I even bought a go kart clone, thinking the pred was out of line vibe- wise and the clone was just as bad. Big motor= vibration.

    My other bike uses the 79cc HF and it is fine - buzzes a bit wound out and no problem.
    Oddly, both machines get the same gas mileage.
    By the way- I disconnected the governor on the little one and it revs out to just under 5 grand.
    The 212 has a tweaked gov and it flattens out powerwise at 4200.
    Both engines re-jetted a bit richer.

    Whatever you put on a cruiser bike- put GOOD brakes on the front end!
    One day you will need to stop RIGHT NOW. And if you can't you can get hurt bad.
    ElGordo67 likes this.
  6. ronphelps

    ronphelps New Member

    Thanks Professor, Can you tell me how fast your 79cc bike will go and what type bike you installed it on. I already have the 212 predator 6.5, I'm not as interested in going fast as much as getting through intersections and up hills without hesitations, safety is important but being able to go fast does not mean that I will. Also do you think you could have done something different at the start of your 212 build to curve the vibrations. I do auto body work for a living and welding and fabrication are no problem. Thanks for your feedback
  7. professor

    professor Active Member

    Hi Ron, I just got back from a ride on the little one-(fabulous Jan. thaw with 65 degrees) it power peaks right at 5 grand, mounted on an old Huffy mountain bike that I stretched 3 inches. With gastank and muffler removed, it sits up in the frame.

    I put the gastank on the top tube covered with a camera bag (like a motorcycle "Tank bag"). The bike looks like nothing one would want to steal- engine is covered with bags too.

    I am using a sturmy archer 3 speed as a jack shaft, the bike goes just over 30 (depending on the weather- goes faster in the cold).
    I was looking at the tach and not much at the speedo- second gear will rev out to 5 thousand - maybe 25-27 mph and high gear flattens the motor out rev-wise but goes a little bit faster.

    Most of the time I am crurising at around 20 with a very relaxed engine speed. That is bike one.

    Both bike one and two need to be registered (NY) and need lights, so I use 24 volt scooter motors driven off a pulley (half speed of the engine) to drive lights. Both bikes have the engine mounted on a plate welded to an added cross bar. Both use belt primary drive with idler and HT type handlebar lever.

    Bike 2 uses the 212 and single speed drive (not sure of the ratio), moped wheels, full suspension stretched bike frame.
    What I don't like about this is I can't pedal with the bike beyond 10 mph- no multiple gear-set like the bike one. But it rides and handles like a small motorcycle- nice.
    Currently, am using cruiser bike chain on the engine final drive, but because of clutch slippage (really need a bigger engine pulley for more wrap around)- I have not shredded the drive chain. Probably would brake it if the clutch would bite hard.

    Other guys mounted the 212 on an angle onto the seat-post tube and used a cvt - works real well, but I do not know wether the vibe issue is any better mounted that way.
    The cvt is a couple of hundred bucks and would surely turn the bike into a small rocket.

    To control vibration, I use "Isolators" from Mc Master Carr. they are cylindrical rubber deals with bonded in studs. I placed one each instead of the normal engine mount bolts, and one on each side of the top (to control engine twist).
    These work very well. Fortunately, I had allowed just enough room to the top tube of the frame to raise the engine with them.

    The 212 actually makes about 9.5 hp @4400 rpm when the exhaust is opened up and the aircleaner off (actually the stock air cleaner may not restrict it but the dyno test done by a member of Bob's 4 cycle gokart forum had done the test minus the aircleaner).
    I run a real long exhaust system with a gutted moped muff and re-jeted carb. On a 120 pound bike you feel some power.

    I took some pics, but this computer is a puzzle to me- tomorrow I will try to post some on the other computer.
  8. Shep0317

    Shep0317 New Member

    I put the predator 6.5 H.P. on my stretched beach cruiser trike, it's scary fast and does around 55 m.p.h.
  9. ronphelps

    ronphelps New Member

    Hello, Professor. Thanks for the reply and information. Don't think I will be riding here for a while, it's 3 degrees in the day and below zero at night. Can't wait for spring. I think I will also lengthen my bike or the next one I get to take the 6.5. The one I have now is an 80cc engine kit and it is very unreliable but it does go about 25 to 30mph. This one I will be getting a 79cc from HF. It will have a jackshaft and centrifugal clutch along with all the lights also removing the governor. This I think should be simple and good enough for me. I do have a Laser 5 49cc moped that will only go 30 to 35 mph and is a gutless wonder at stop signs and hills. It's all fun to work on. looking forward to your pictures to size up the frame Thanks Ron
  10. ronphelps

    ronphelps New Member

    WOW. That's just too fast for me but good to know that you can, which is what I would like. Also being able to stop is a must Thanks Shep0317.
  11. professor

    professor Active Member

    Three inches is a good amount to add to the frame. It smoothes out the handling.
    Here are some pics of the 212 bike.
    Now, this bike is real long (looks weird - handles awesome) because I extended the rear section (a little too much) for the full suspension.
    I just figured out how to attach pics with this new format :rolleyes7:-

    Attached Files:

  12. professor

    professor Active Member

    Here is bike one, a pic of an isolator and my thumb throttle made from a gear selector-

    Attached Files:

  13. Milkshake

    Milkshake Guest

    Hi everyone. I weigh 203 pounds and I currently have the 49 cc 2.5 horsepower. And it barely pulls me up hills. I have to pedal and the engine strains a little. so I thought about getting 212 CC Predator engine, but I read that that one has 6.5 horsepower and I was thinking it should have no problem pulling me up the hill. But I don't really want to spend that much money so my question is will the smaller Predator engine the 79 CC marked at 3 horsepower be good enough to pull me up hill? I don't really know what half horsepower more would do.
  14. Frankfort MB's

    Frankfort MB's Well-Known Member

    The 79cc is right at the same price as the 212cc.
    I'm actually in the process of building a 212 predator bike

    The hardest part about a 212 is the shear size of such a big motor:p
    I had to chop up an old frame to get it too fit...
    I'm also working on wheels for it too. It's going to have a double wall rim with disc brake in front with a double wall rim in the rear (I'm not running pedals so hub mainly just spins lol)

    My engine actually has been used for a racing go kart engine that's been rejetted, shorty straight pipe exhaust, UNI high flow air filter, heavier valve springs, removed governer.... I can't remember something else:)
    It has a CVT clutch that came with the engine that takes a 35# chain I'm going to use but I don't know how to put a sprocket like that on the hub.....
    Any suggestions or comments???

    I haven't rode the bike yet since I'm still building it:) but so far the engine seems like a good powerplant (It's a foot wide so that will be fun:p)
    I'll post later with my feelings on how the 212 can be used:)

    Attached Files:

  15. bakaneko

    bakaneko Active Member

    i dont think the 49cc is actually 2.5 hp. lots of funny conversions and which hp metric used and etc going on
  16. bakaneko

    bakaneko Active Member

    gluck, man. looking forward to seeing the it running
  17. saw

    saw Guest

    Well Milkshake, it sounds like something is geared wrong here...I've built a few of these with the same engine to include a tandem that the wife and I ride up hills without problems. Is your engine reaching max rpm? Using the right fuel? 87 octane..the good ole cheap stuff? Did you make sure the fuel tank was nice and clean before the build? You would be surprised at what I've found inside of them. A clean fuel filter? I've had to take the carb apart before..cause there was junk in the jets also.
  18. darkangel

    darkangel Guest

    Putting a 212cc on a bike is not impossible, hundreds of people have done it including me, just have make sure you have good parts, beefed up rims are a must and brakes, im building a 212cc with a turbo, and fuel injection kit, about 4k just in the engine, yes some will say its stupid but i want to build my dream bike. To give an idea about rims, mine are being custom made and are costing 600, and doing a custom low rider frame, when thinking about a frame just keep in mind you will need 16"x13" high just for the engine and that is without a gas tank on top, but you can remove the oil sensor and mount it vertically (valve cover sticking up) i was told i couldnt do a turbo and im going to proove everyone wrong. Hope this helps any.
  19. Yeah i guess you'd recomend to watch a skydiving movie instead of accualy doing it IRL.