How about twin engines?



:cool:just wondering if any member has twin engines on their bikes, such as V-2, inlines, even front and rear rack mounts?


Twin engines were a real pain in motorcycling. One ends up pulling the other or they develop sympathetic vibrations as they run in and out of sync.


grrr!!! i wanted to make the first dueling engines, and i thought about front anbd rear mount! too bad i cant do it...not old enough to get a over these chinese pieces of junk. im goin 4 stroke honda. no problems there!!!



Heh heh heh...A man after my own heart....I was thinking the same thing...Side by side driving a jack shaft that ultimately drives the rear sprocket...Of course the pedals may have to go bye bye in such a conversion unless somehow the frame is lengthened.....How about 2 engines...One driving the rear wheel and one driving the front wheel....2 wheel drive!!! Oh yeah!

just for kicks

How about two pocket bike engines arranged front to back, each motor keyed/timed to a common center gear that has a clutch that then outputs to a jackshaft.
So two 8+ HP 2-stroke pocket bike engines (W/boost bottles) and a small gear on each crankshaft timed to fire 180 degree's apart (every stroke) and driving a large center gear that has a clutch with either a chain or gear driven jackshaft.

LOL it would probably self destruct.


If you gotta take the pedals off, you might as well go buy a big scooter or even a V-twin Hardley Davidson.
I like the thinking out side the box though.


Completely do-able with minimal welding!

:cool:how about two 80cc chinese engines, side by side on a mounting plate, midframe like the single engine. both engines share the same chain-driven jackshaft, which then drives the rear sprocket. none of the sprockets are free-wheeling. chain adjustment to the engines' sprockets made by slotted engine mounting holes. chain adjustment to rear sprocket via axle adjustment in rear dropout. both engines are individually or simultaneously kick-started,then controlled by their own clutch and throttle levers.

actually this idea is not too far-fetched or involve expensive exotic parts and extensive labor. welding should cost less than $100. since two engines measure 9.25" wide, side-by-side, start with a 12" square steel plate, one jackshaft w/3 sprockets, 2 short lengths of #35 chain, t-fitting on the gas petcock, extra clutch and throttle levers and the rest of the single chinese engine kit.

as an added bonus, gear ratios are easily changed at the jackshaft. the rear sprocket remains untouched.

if one engine fails or ya wanna run just one engine, just disengage the clutch and pin the lever.

what i would need is an old cruiser with lots of room in the midframe to clear the crankset.

and i JUST happened to have two new chinese engine kits in my cabinet.:cool:

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How about this custom? Now this is NOT mine, but belongs to an acquaintance.
It has some those problems, and isn't very fast, but the point was in the building of it, not the ultimate top speed.
It uses two Whizzer cylinders, the rest is custom fabricated. There are 9 seperate pieces that make up the crankcase...
It runs fairly well.
There's also the now known, 'Double Whiz' with two whizzers mounted in tandem with a flex coupler from a Cushman truckster, and run through an Albion three speed... Also not my bike, but a friend's bike


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:cool:i thought about searching for an engine coupler, but that'd make a twin-engine project more complicated/expensive/frustrating for me.

in my case, it'd be "form before function". the second engine need not run; just being in the frame looking good is its primary goal.

and methinks it WILL run. maybe not run well, but baby, all i need to do is start both engines, crack open both throttles...and idle.:eek: