Onyx 29 inch with 79cc Predator

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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The governor removal was a why not moment, the engine was lying on the table, I had a beer, I took it off, I really don't for see blowing the little feller up, and again I m just looking to tootle around the neighborhood not break any land speed records, lol.

I played with the clutch guard and riveted an old license plate onto it, I haven't decided if I like it or not yet, I have been using old bits and pieces on the bike where I can.

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The only hole needing drilled in the frame was for the rear brake, the front had an existing hole for the brake assembly, the brakes are Tektro, hooked into a single throw lever for front and back.

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Man the thing looks beat up in the pics, the camera flash on all that black is like a black light at a Holiday Inn, :LOL: it needs a good wipe down. I used old lions head furniture brass for the bar ends.

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I didn't care for the round speedo and picked up an old Dorcy, a little leather and silver conchos to tame the cables.

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I also used old brass furniture claw feet for hub covers.

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One small screw on top, the bottom is slotted to fit around the fender support and a small piece of rubber filling the bottom space, solid as a rock, easy to remove.

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Cable ties are leather with silver dollars, quarters, buffalo nickels, and a fifty cent piece for good measure.

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I switched the tires out to Thickslicks, I love white lettering on tires, I'm a product of the sixties and seventies.

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I installed a center stand making my life much easier, after a few hours of standing in various hardware store plumbing isles I came up with an exhaust solution, I cut the kit pipe down to about one inch, then used the kit adapter and slipped a 45 degree fitting over the cut off stub of the old jumbo ugly log muffler, 3/4 on each end of the 45 coupler, a 5/8 sleeve cut to where another 45 fitting would attach each together, 5/8 straight run down to rear hub, another 45 fitting and 3/4 out the back. I installed a bracket coming off of a valve cover bolt then bolts to clamp surrounding the sleeve and two 45 fittings, this applies pressure around the fittings and gives a good tension fit where the fitting slides over the one inch cut off coming off the adapter. At this point everything is rock solid at the start of the exhaust run, I cut my pipe to length slipped it into the top assembly, slipped on the bottom 45 and again used a two piece clamping from the frame then bolted to the exhaust clamp on the rear tail pipe which is 3/4.
That probably made no sense, lol.

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Just playing around with headlights. I made the first clamps from aluminum, the attachment bracket is steel, I have moved the rear clamp and fabed it out of copper to better blend in, the bike changes all the time as I try different things on it, which is actually kind of fun.

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Another trip to Ace Hardware and a small sheet of aluminum that I used to fab up a fairing for each side to cover the ugly thing known as the bicycle motor mount, that big gap under the engine bothered me, it needed a little more something something down there and I had a couple of old truck tonnage tags from the forties, and the holes matched the side holes in the motor mount ends perfectly, so 1 1/2 tons it is.

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The motor mount bolts are long enough to double nut, so the locking nut on each end holds the fairing, then two small screws into the preexisting holes in the side mounts through the tonnage tag holes, painted them black.

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Governor does nothing but limit the throttle from going wide open, there for limiting rpm's. take the gov. off and the motor revs higher Like i said before, with gov. 22 mph and take it off and 32 mph..............Curt
 
Governor does nothing but limit the throttle from going wide open, there for limiting rpm's. take the gov. off and the motor revs higher Like i said before, with gov. 22 mph and take it off and 32 mph..............Curt

The lower fairings add at least three mph, the brass monkey paw hub covers at least another two.
 
On the other side of the bike I ended up using an old brass cup for the air cleaner, it bolts directly to the carb so no chance its getting kicked off, it is still a work in progress, the Prince Albert can covers the motor mount bolts that stick up, and it makes a handy little tool box, adds a little color and fills an empty spot behind the engine.

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I am going to try and install one of those gravity brake lights into this assembly, dug the old bicycle tag out of my folks garage. I think mid seventies was when they went to a decal tag instead of the steel plate, I can remember riding down to Otascos as a kid in October to get a three dollar bike tag. I always removed them as they rattled big time, this one looks like I never even put it on the bike, the old tags would expire on a kids day, Halloween. I don't think they even tag bikes anymore.

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nice to see more peeps getting into the mid-size 4 strokes :D,, what back sprocket do ya have? Like Will mentioned a while back, I like the idea of a few more cc's with the LF160F. and yeah, stuffing any clone engine into a frame is not easy, I want to tape a bomb to the mount plate and mail it back to the seller lolz. What I'm doing actually is I got a much better plate, the CNC vertical one, but I'm not mounting it vertically. who says ya gotta? haha.
I almost got an Onyx too. can't wait to see yours all done
 
nice to see more peeps getting into the mid-size 4 strokes :D,, what back sprocket do ya have? Like Will mentioned a while back, I like the idea of a few more cc's with the LF160F. and yeah, stuffing any clone engine into a frame is not easy, I want to tape a bomb to the mount plate and mail it back to the seller lolz. What I'm doing actually is I got a much better plate, the CNC vertical one, but I'm not mounting it vertically. who says ya gotta? haha.
I almost got an Onyx too. can't wait to see yours all done

The sprocket is a 48 BBR from Bike Berry, I don't mind the extra work to get things to fit, that's the fun part, lol.
 
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