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offroadsubaruguy

1100cc motorcycle engine and tranny in a justy?

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just wondering if anyone has thought of this...... i think it would be awesome. all you need is a 4wd four door justy with a bad motor and trans.... find a motorcycle with an 1100 and a tranny with a driveshaft instead of a belt or chain drive.....remove the motor and trans from the justy, drop in motorcycle motor and trans, connect the driveshaft to the rear diff and there you have it! instant power gains and weight loss so you would have better power to weight ratio, plus you now have a motor that turns around 14,000 rpms!!! if you wish, add a turbo and you have one smoking justy......:brow::brow::brow:

 

the only issue i could see with this is the emissions.. how would it work? motorcycles ony do emissions once, and thats it, cars on the other hand at least once every two years..... anyweay, it was just a thought.... let me know what you guys think....

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its do-able. this months c/d had a lotus 7 replicars article, one of which ran a 919cc honda engine and tranny. the engine leans to one side, and if you were looking to have good handling, the justy would have to be rhd.

 

and it wouldn't need smog testing if you lived in a state that didn't have smog testing, like virginia

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reverse: electric motor attached to one front axle or to the driveshaft somehow

the best part IMHO would be the sequential 6sp. I would do an older GS1100 with a small turbo maybe 10psi or so to not break the trans. yet get a little torque as well.

also would be cool to just cut a hole in the rear floor and mount the bike trans output straight onto the justy diff.

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reverse: electric motor attached to one front axle or to the driveshaft somehow

.

 

Thats what we came up with too, 24 volt cordless drill!

 

( hypothetical Moto Guzzi 1000cc into Fiat 500 scenario about 3 years ago )

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BMW bikes just about all are shaft drive,

Moto Guzzis as well (hence the idea for the Fiat heart transplant)

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why not just use a suzuki swift gt engine and trans? they are 1300cc, with 5sp and reverse. they are very simular to a crotch rocket motorcycle engine, dohc. heck, they even sound like a crotch rocket lol. those motors have a crazy power band like a bike, it kicks in at like 6-7k rpm.

 

just something to consider........

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3 reasons a bike engine would be cooler:

weight(~ 170-250 lbs for complete bike engine setup)

revs

6sp sequential shifting

though any swap into a justy would be totally bad rump roast.

 

there are several large bikes that use a shaft drive, but are all aircooled which wouldnt be the best for a car

suzuki GS1100

yamaha XS1100

yam virago 920

honda GL1000 aka goldwing(eh mudrat357?)

etc etc

these older motors are available for under $500 all day(oftentimes much less) and can possibly take some boost because the CR is quite low, at least on the yamahas. the real issue in my mind is wether or not the trans could handle any kind of abuse when you triple the weight it has to move.

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the main idea behind this thougth is less weight, more power... thats basically it. i had actually thought of doing the mid rear idea, but then figured i might want the rear seat still..... all in all it would be pretty simple to do ... i just need the car and the motor and i could do it.... till then, its just a thought.

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... but are all aircooled...

honda GL1000 aka goldwing

Ummm... The GL1000 through GL1500 are all watercooled. I suspect that one or two others in the list are also watercooled.

 

The transmissions would not likely hold up in a car. There is a difference between accelerating 800lbs and 2000+lbs.

 

I also have not seen anyplace near me that sells inexpensive motorcycle drivetrains. Perhaps buying a wreck from its owner, but not by buying something from a dismantler.

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sorry, you are correct the GL's were watercooled. I added that to the list after writing the aircooled bit.

gs1100's, viragos, and xs1100s are definitely aircooled.

bike motors tend to go cheap on ebay if you do not mind buying an engine sight unseen or parting out a bike can get you a cheap motor.

a bike engined justy would weigh 1500lbs or so. and even lower would be possible with some cutting.

there are many bike engined cars, but mostly minis which are light as heck, and lotus 7 type cars which are even lighter. personally I would use an R1 motor as they are proven in cars, watercooled, make a ton of power, and can be had for a grand.

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Another thing is torque. These bike engines may have high HP ratings, but that's because they rev at 12K to 14K RPM.

 

Been done to lots of other cars before. Sometimes people keep the cars gearbox and just have 4th (straight thru gear) and reverse. Personlly I'd use a flat four in a justy, but that's just me.

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i would be all about using a 360...... except for the fact that i cant find one that doesnt run in the area..... heck, the only ones i can find are in new york, kinda far to go for a car....:-\:-\:-\

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Me and My Brother have been working on this very senerio for a while now and It seems it might come true for one or both of us. I Have an MG Midget and just bought a Suzuki TL1000R as a donor bike. (only $900 for a banged up one) My Brother Josh is currently looking for a 360 to use as his platform So if anyone has one for sale just let me know.

 

Here's Where I need some help. I've got a Front-engine rear-drive car.

 

How do I keep the driveshaft still? The bike is chain drive so Theoretically i could just weld the drive sprocket to the driveshaft. I'd like to gear it down though. Any Ideas? Josh suggested using a Transfer case from a justy or something small. Let me know what you think.:brow:

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I'm not sure if the driveshaft would be geared down enough, does anyone know if shaft driven motorcycles are geared down at the rear wheel? Also most shaft driven bikes don't red-line at 12,000 RPM. And I already bought a chain driven one.

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if its going to be rear drive then all you have to do is change the gears in the diff right? you might want to see about mounting the motor in tranvsverse style and play with that..... just a thought.

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most of the modern cruisers from honda, ect are shaft drive.. the bmw boxer is shaft (and a 2 cyl boxer :brow: ) but your only looking to get about 100 to 150 HP from a motorcycle engine :burnout::lol:

 

i would find a wreked hayabusa, and try to get that chain driven thing to bolt up somehow.. it could be done.. just build a sproket adaptor somewhere in the car.. or build a front diff that is chain driven... :rolleyes:

I still thing a justy might be too heavy for even a fast bike engine?

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a lot of bike motors stand up to turbos ok, which gets you some torque.

I would imagine that getting a justy down to 1400lbs or so would be pretty simple especially once you break out the cutoff wheel and go from a heavier car drivetrain to a bike one.

R1 motors are super light and compact.

 

would be cool to have the motor in the hatch to put another sprocket on the diff input and run a chain drive that way, or put a driveshaft yoke on the motorcycle trans output sprocket and put the motor up under the hood like a legends racer.

 

2 bike motors would be better than one though.

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