Onyx 29 inch with 79cc Predator

Wichita

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Jan 10, 2019
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I picked up an Onyx cheap, rode it down the block, and decided it needed a motor, and I needed something to kill some time with this winter. I've been tinkering with it for a couple of months, I'm in no hurry, a few hours a day figuring out what works and what doesn't, and way to much time standing in the isles of Ace Hardware, lol.
The start of the project.

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Will'smotobikes19

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Do you have the motor yet? I’ve noticed a 49cc gxh50 clone can be a better choice it’s smaller can rev to over 7,000 rpm, get in the high 30’s the predator is only 3600rpm so it may be sluggish especially with a 29” I think my clutch was crap though so might just be me. Even with full throttle I had to pedal to get going or the bike would sit still. Once it got going I estimate about 30 even mph. The lf160f (lifan) may be a better choice it is 118cc more power. The 79cc bike is in my profile pic. Running a 2 stroke now.
 

Wichita

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Jan 10, 2019
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I bought the Beast kit from Bike Berry, I used some of it and chucked a lot of it in the trash I figure I still got my monies worth but you would think they would have a deluxe kit with better quality parts to go along with the cheap just barely get you running kit. I started with the big question, will the engine fit, the answer was barely, I removed the bottom oil plug that sticks out almost dead center of the engine as it was going to ride the frame, Ace Hardware and a flush hex head plug and all was good, I will just tip the bike up to dump the oil. The valve cover was a no go, so I ordered the shorty cover from Gas Bike, the engine now had plenty of valve cover and sparkplug clearance. The motor mount was questionable, the platform was a deformed mess, if you set it on a flat surface two corners were off the ground by quite a bit, a trip to Ace Hardware and I purchased a steel plate from their stock metal bin, perfect width no cutting with two inches off the end, sturdy 1/8th steel nice and flush. The engine has to sit as far forward as you can with out riding the frame, and the rear corner just clears not super tight but close.

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I thought the addition of the steel plate would cure my woes, nope, the end mount bolt holes are drilled to high so with bolts installed the plate rides the head of the bolt. At this point I will add that I used no bolts provided in the kit, trust me Ace Hardware is your friend, I ended up having to file a corner off of all four bolts to get my plate down flush with the mounts, not enough to effect the integrity of the bolt just enough to clear. Yo, bike kit sellers tell the manufacturer their holes suck, as does this mount in general, It can be made to work barely.

The bike is nice in that I can work on it in my hobby room, I like heat, lol.

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Wichita

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Joined
Jan 10, 2019
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18
Do you have the motor yet? I’ve noticed a 49cc gxh50 clone can be a better choice it’s smaller can rev to over 7,000 rpm, get in the high 30’s the predator is only 3600rpm so it may be sluggish especially with a 29” I think my clutch was crap though so might just be me. Even with full throttle I had to pedal to get going or the bike would sit still. Once it got going I estimate about 30 even mph. The lf160f (lifan) may be a better choice it is 118cc more power. The 79cc bike is in my profile pic. Running a 2 stroke now.
I pulled the governor and oil sensor, not that I'm looking for fast, low and slow works for me, but we will see, I'm still in the putting it together stage, mainly for lake bikes this summer when we camp.
The twelve year old in me bought the Apes.
 
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Will'smotobikes19

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My frame was a good fit for the predator it happens to be called the micargi predator it’s a stretched beach cruiser. My coil went bad for some reason but I got a new one and I think it will run again, has spark. Going to throw away the crappy clutch it wobbles like crazy and I think it was slipping. I have mag wheels on the bike and I think it would look good if I put the predator back on.
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Wichita

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Jan 10, 2019
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I installed front and rear brakes with single pull lever along with steel stiffener trim piece down the fender centers, a cheap speedo, the better Bike Berry throttle control and bobbed the rear fender, a hub adapter was also installed, you can also see the steel plate motor mount in this pic, and played with the tank mounting a little.

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Wichita

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Jan 10, 2019
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I really didn't care for the exhaust provided in the kit, and the after market exhaust pickings are pretty slim, the air filter is pretty lame also and is going to get kicked off the mount with pedaling. At this point I had declined using these parts from the kit, the throttle grips, the platform of the motor mount, the rag joint and sprocket, the air filter, and the exhaust, and all nuts and bolts. I painted the fender braces and underside of the fenders along with the kick stand fire red for a little color. I used aluminum shimming material between the frame mounts and frame, it is used in the aircraft industry, you can peel it down three thousandth at a time enabling the making of a tapered shim, grinding was out of the question with these mounts, it would take way to much meat out of the mount. The aluminum shim should prevent damage to the aluminum frame.

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Will'smotobikes19

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What do you think the chance is that the motor will break a rod without the governor? 2.5 hp I'm assuming it's only 4 or 5 horse without the gov so it may hold up. I think they make heavy springs. May have to put my 79cc back on but how wide it is is kinda annoying after having the 2 stroke though. I used gasbike parts (transmission and top shield). I got the motor from harbor freight about 3 years ago.
 

curtisfox

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May 13, 2010
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What do you think the chance is that the motor will break a rod without the governor? 2.5 hp I'm assuming it's only 4 or 5 horse without the gov so it may hold up. I think they make heavy springs. May have to put my 79cc back on but how wide it is is kinda annoying after having the 2 stroke though. I used gasbike parts (transmission and top shield). I got the motor from harbor freight about 3 years ago.
Governor does not give any more hp, it just limits the rpm's, little more rpm's a little more speed..........Curt
 

Will'smotobikes19

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How do you tell it doesn't add hp have you dyno tested? if the gearing isn't changed you can't add more speed without getting more horsepower don't they rate stock motors with the governor? Stock the minibike went 22mph but without the gov 32mph 10:10
 
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