cylindar forward 212 preddy

Through a lot of reading here, I am aware that other people think the motor should face forward and that cooling would be better when oriented that way. I never thought my idea would be an original one. With the speed of things now days, someone will likely have something for sale by the time I start a second bike build. This first one is just for transportation and is a friction drive with the engine placed in the frame, where it belongs.
I actually made one back in the 60s by just taking a couple seat clamps and wrapping them around the lower tube beside the rear wheel with a bolt through the mounting holes in the engine and a chain to keep it from falling down. Had to ride with the bike layed over almost on its side so it didn't last long but I remember it was fun.
 
MotorBicycleRacing said:
B & S Animal hand built in Milwaukee, Wisconsin
HP Ratings out of the box: Stock Max RPM 6100

Pump Gas - 8.8
Race Fuel - 11
Methanol - 12
3/4" Shaft

CNC mastery by Joker Machine Inc.

376827_10150954696082212_1951204541_n.jpg
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8.8 on pump gas? Makes me wonder what my stock preddy is putting out. Is there a thread on that bike? I'd like to read up on it and see how it all comes out.

To address some of the other comments, weather the engine cools better in this configuration I don't know. But I do know with this configuration you can get alot bigger engine into alot smaller frame. The frame I'm using is just a cheap mountain bike frame. Seem to see them all the time out at the dump. I guy I met while riding my china girl gave this one to me for nothing. Of the most common 26" frames I see, this one is on the small side. The top tube is 21" long and is 31" off the ground, and I still have enough room to put in a bigger engine.
 
usflgSorry. Better cooling is just a hopeful opinion. For all I know, cooling the bottom where the oil is may be better than cooling the cylinder. And the way that a bike frame is made with the front support tilted as much as they are towards the front, there is a lot more room to use the longer space up high for an engine where the cylinder is angled up to some degree with the engine facing forward. But the most important reason I believe is that they just LOOK RIGHT oriented that way.
Really, the ability to keep the engine lower in the frame with the cylinder forward is just as important as the way it looks but you gotta admit they do look a whole lot better situated with the cylinder forward.
usflg
 
Is that a jackshaft I see in the bottom bracket of the Joker bike? Sorry, new here and cannot find that build thread, but curious what the final drive plans are. Also curious for the method of reversing the primary drive; I assume it's meshed gears?
 
atombikes said:
Is that a jackshaft I see in the bottom bracket of the Joker bike? Sorry, new here and cannot find that build thread, but curious what the final drive plans are. Also curious for the method of reversing the primary drive; I assume it's meshed gears?
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There is no build thread here.
yes, they are using gears to reverse rotation.

The bottom bracket will be getting pedals with cnced wide cranks to clear the motor just like their GC 160 race bikes.
 
Ok, hope it's not too late to post an update.

First of all, I swapped out that skinny seat for a much wider one (approx. 12")

Second, I just broke my multispeed freewheel. The freewheel mechanism jamed up so I pulled it all apart and found out that the only two pawls are shot. I've seen cassettes that have more than two, just not any multispeed freewheels. Anybody know if there's a multispeed freewheel out there that has more than two pawls?
 
midwestmayhem said:
Does anyone know of a good cassette hub that doesn't cost so much?
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Most wheels are machine built in country's were labor cost a quarter of US. Call LBS and ask for trashed wheels. They may give them to you. I have found them in their dumpster trash. Even a cheap cassette would be better because of it's design than a freewheel IMHO. But the most I would power would be a 4 stroke 99cc, close to stock.
 
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mat_man said:
Most wheels are machine built in country's were labor cost a quarter of US. Call LBS and ask for trashed wheels. They may give them to you. I have found them in their dumpster trash. Even a cheap cassette would be better because of it's design than a freewheel IMHO. But the most I would power would be a 4 stroke 99cc, close to stock.
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Ya, it looks like from thier general designs that a cassette would be less likely to bend axles(which I'm also having problems with). I just figured there might be a way to throw the 3/8 axle swap in a 14mm. I know a machinist, maybe he'll be able cut in extra pawls. Just have to measure accuratly so they'll all engage simultaneously.


JonnyR said:
i dont know how good the brand is and i hope some one has the answer because they have what i need the disk brake mount is great for bolting a sprocket on

http://www.ebay.com/itm/Bicycle-Bik...Cycling_Parts_Accessories&hash=item1c2ba812e9
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I'll check into that one. I usually don't approve of a qr, I've broken them on a regular bike. But there are solid replacements out there. I was hoping to find a disk hub in the event of a hub swap.
 
midwestmayhem said:
I just figured there might be a way to throw the 3/8 axle swap in a 14mm.
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At least replace the quick release with a high strength solid axle.

midwestmayhem said:
I know a machinist, maybe he'll be able cut in extra pawls. Just have to measure accuratly so they'll all engage simultaneously.
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I think you are using a shift kit.
The Shimano FF (front freewheel) System's rear cluster does not freewheel.

I am wondering if you could braze, glue or pin the cassette cage solid and not freewheel? I think this would would work better with a V belt primary and a hand clutch. A belt would slip a little and give less shock to the secondary.
 
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mat_man said:
At least replace the quick release with a high strength solid axle.



I think you are using a shift kit.
The Shimano FF (front freewheel) System's rear cluster does not freewheel.

I am wondering if you could braze, glue or pin the cassette cage solid and not freewheel? I think this would would work better with a V belt primary and a hand clutch. A belt would slip a little and give less shock to the secondary.
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axle swap from a qr to solid would be a necessity. yes the motor is powering the multi speed freewheel. There is too much drag in the rest of the system to not use one. So if I was to run it solid with everything else the same, it would eat the derailleur. I'd prefer not to redo the primary if possible.
 
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