Any possibility of a motorcycle motor?

[Rickieh]

I'm a bike guy, I currently have 6 bikes and one of which was just laid down. The bike still runs and shifts just fine but the plastic is beyond repair. That being said has anyone ever toyed with the idea of a motorcycle powered 4 wheeled kit car? I know there's trimagnums and what not out there, but I've seen four wheeled cars powered by bike engines before. does anyone know how the drivetrain would work? Is there an adapter to hook it to a car transmission? Would it use the bike transmission? The bike is chain drive and the car is shaft...what can we use?

The perks I see to this are...
Compact engine size. very rarely will you See a 1600cc bike engine or more. The one I have is a 750 and puts out around 110 hp. this would be plenty enough for a fiberglass car and should fit.

it's air cooled.worst case scenario I would just be relocating an oil cooler but the bike engine I have spare is air cooled.

more power more speed more acceleration

A cheap alternative to modifying a car for a bigger engine

 

[islandman]

There are plenty of bike engined kit cars and variants out there. These are all typically in very light weight small cars. This is for a reason, Bike engines typically don't have the required torque for heavier vehicles.

 

[letterman7]

Been discussed before, but as David mentioned, bike engines are HP at high RPM and a modest torque curve. Even my flat 6 1500 cc Honda Goldwing engine wouldn't be enough to motivate a Sterling safely. It's rated output is about 100hp with 110 lb/ft of torque at 4K rpm. Which means you'd have to really run up the engine to get off the line. Keep in mind the average wet weight of one of these cars is still close to 1700 pounds... most motorcycle driven cars are less than half of that.

 

[islandman]

To give you an idea of a car's weight I have actually weighed my car on a weighbridge, with half a tank of gas and no driver and it comes in at 1,000 KG, which is 2,200 Lbs. This is with an alfa Romeo 1.7cc cloverleaf engine, which obviously has a radiator as well. So the VW units will come in lighter but probably not by much.

 

[Brett Proctor]

does anyone know how the drivetrain would work? Is there an adapter to hook it to a car transmission? Would it use the bike transmission? The bike is chain drive and the car is shaft...what can we use?

The perks I see to this are...
Compact engine size. very rarely will you See a 1600cc bike engine or more. The one I have is a 750 and puts out around 110 hp. this would be plenty enough for a fiberglass car and should fit.

it's air cooled.worst case scenario I would just be relocating an oil cooler but the bike engine I have spare is air cooled.

more power more speed more acceleration

A cheap alternative to modifying a car for a bigger engine

As mentioned this has been brought and I think what really killed the idea for me was the engine wasn't designed to handle the loads that would be put on it.

People have done it and there are videos of it being done so it is possible but as I said the engine wasn't designed to handle the loads being exerted on it.

What I'm talking about is the crank and the main bearings. The surface area of the main bearings and the size of the crank is the achilles heel.

Cranks can break and the bearings wear out prematurely.

Because of the weight of the car the rear wheels wont break loose as easy(under acceleration and compression breaking) and the crank is subjected to higher loads, as for the bearings, the width is very narrow and the loads can't be spread out over a greater area so they may wear out faster.

I believe the bikes transmission and clutch are used also in the conversions and that may be a weak point also. Gears and clutch aren't designed to handle the loads either so those may be open to failure.

If your still going forward with the idea do a search for "dwarf cars". You should be able to find all the parts and info you need to do the conversion. I'm sure there are forums out there on dwarf cars that you can join and get better answers to your questions or call the companies that are selling parts for them and ask them.

As for us, nobody has done it so comments are just guessing at it(that includes my comments also)

Here's a place to get you started
Driveshaft Adapters | Hawk Machine Co

 

[Nic]

Hayabusa engines have been used in buggies, but those are a lot lighter (less fiberglass, glass and chassis). So a motorcycle engine has been adapted to a VW trans and can be done. But again, like everyone else said, they probably can't handle the extra weight of a fully loaded Sterling. Sadly.