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914World.com _ 914World Garage _ Harley style Vtwin swap?
Posted by: SLRPY MN Oct 7 2015, 10:44 PM
Pulled the 1.7L out of my 1972 914 the other day to chase down some issues ive been having trying to get the engine to turnover properly. and being the freedom loving harley davidson riding american i am (also with constant shit getting i recieve from my roommates) we've been throwing the idea of using an Aircooled V-twin 100cu in plus Harley engine as a powerplant to reduce weight and add power and i can't help to ask why haven't i seen this yet.
so far our idea is build a Flange on the Crank that bolts to an aluminum flywheel then the 914 transmission...
I'm open to ideas and criticism... 
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Posted by: Mueller Oct 7 2015, 11:09 PM
Sell Harley motor, buy S&S motor instead 
Not too crazy...
http://thekneeslider.com/motorcycle-powered-cars/
A few pretty neat ones using motorcycle engines...even the V-twin
http://thekneeslider.com/harley-davidson-powered-cars-four-wheel-cruisers-with-a-hint-of-milwaukee/
Posted by: SLRPY MN Oct 7 2015, 11:13 PM
To be completely honest the idea is to use an S&S 113cu in or 124 cu in...
Posted by: cali914 Oct 7 2015, 11:36 PM
To be completely honest the idea is to use an S&S 113cu in or 124 cu in...
how much hp does the Harley motor put out? Thanks Harry
Posted by: Reno914 Oct 7 2015, 11:38 PM
To be completely honest the idea is to use an S&S 113cu in or 124 cu in...
That would be awesome! Those motors make good torque too, I think over 125 ft-lbs.
Reno
Posted by: SirAndy Oct 8 2015, 12:05 AM
My best guess would be because those engines were not built to schlepp around a 2000+ lbs car.
What does the torque curve look like on one of those?
I would hate to have to sidestep the clutch at 8000 rpm every time i want to get going ...
Posted by: gfg3 Oct 8 2015, 04:46 AM
I'd be a little worried about cooling. Those big twins normally sit out in the airstream.
Posted by: DBCooper Oct 8 2015, 06:09 AM
My best guess would be because those engines were not built to schlepp around a 2000+ lbs car.
And that's a pretty good guess, I'd say. All the cars I've ever seen with motorcycle engines are exceptionally light, unlike the 914. Although some of those big ol' Harley riders, two up, do probably come close to that 2000 lb. barrier.
And as a heads-up I just read about the adaptation of the S&S engine to the new Morgan, and they found that the torque pulses from the big V-Twin hammered the drive train so much it broke things. They ended up using a rubber coupler between the engine and transmission to soften the blows.
Posted by: Olympic 1.7 Oct 8 2015, 06:11 AM
My best guess would be because those engines were not built to schlepp around a 2000+ lbs car.
What does the torque curve look like on one of those?
Being a big Harley fan you would think I would jump on this idea. But I would recommend against it.
First I think cooling would be an issue. Second the money you would spend on a built Harley type S&S engine would be better put towards a SBC conversion. Or just building up the stock engine you have.
My touring bike has a built 117 ci engine or about 1920 cc. with a bike weight of around 800# and add another 450# of passengers and gear loaded for a trip = 1250# now it does run really good and has no problem exceeding 100 mph for extended periods. ( on a closed course obviously
) having it pull around 2000+ lb car would be underwhelming. when you consider the barrels of cash I dumped into this engine to get it to this point, you would be better served to spend that money on rebuilding the 1.7 into a 2.0, a 2056cc or larger. and everything just fits in. FWIW here is a copy of my Harley 117 dyno run.. top line is HP read on left. bottom line is torque read on right.
rev limiter is set at 6250 thats why dropoff at end.
Posted by: DBCooper Oct 8 2015, 06:18 AM
Wow, that's impressive torque. I've never seen a Harley (or S&S) graph before. Very cool.
Posted by: RobW Oct 8 2015, 07:43 AM
Wow, that's impressive torque. I've never seen a Harley (or S&S) graph before. Very cool.
That's a nice readout for a Harley....
Posted by: HalfMoon Oct 8 2015, 08:08 AM
Hmm...perhaps a water cooled motorcycle engine? Hybusa?
Posted by: mbseto Oct 8 2015, 08:15 AM
Get 2 twins, and just swap in the cylinders and pistons. :-)
Posted by: veekry9 Oct 8 2015, 02:32 PM
A shroud and fan to cool the whole block is needed to keep things unmelted.
An expensive way to arrive at an aircooled 4.A six however is more appealing. 
A unique solution to the need for speed.
SportyPrincess,at what weight is too much?500Lbs?
Posted by: ClayPerrine Oct 8 2015, 06:14 PM
Something like this:
That is a Toyota Prius with a Harley motor in it. They call it a "ToyoHog Hybrid-Davidson". It was built for the 24 hours of Lemons racing series. It is the slowest, loudest thing on the track.
Here is a video of it running. We were there watching it race.
https://www.youtube.com/watch?v=yK2AxFpOh14
Fun idea, but if I remember right, it kept eating clutches.
Posted by: SLRPY MN Oct 8 2015, 08:21 PM
So I agree with the concern for cooling In which my major ideas to solve this is to fabricate some duct and shrouds to scoop air from under the car and behind driver and passenger side of the roof... possibitily of using some electric fans to drive some fresh air in...
Second the weight the weight of Stock harley built Triks already push 1100 1200lbs using their factory engines which i intend to use the built S&S motor, which later in time if successful may consider the investment to upgrade further to the S&S T143 just so i can be pushing close to 150 ft lbs and 160 HP, as linked below.
http://www.sscycle.com/files/9714/1444/1300/t143-dyno.PNG?
but someone mentioned something about the oddfire causing Pulsing that may actually be one of the biggest concerns i've heard about...
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