Hello from thaddeus... also question...

[thaddeus]

Hi,

I am getting deep into the design of one of these autos. So here I am. Seems like there's a nice group of like-minded folks here.

I am still in the planning stages. (Although I spent some time working on the pedal box today; seemed like a relatively generic subcomponent that wouldn't be changed much by my other design decisions-to-be and I wanted to start working metal). But anyways:

The idea of using a motorcycle engine seems very attractive to me. High-efficiency, high revving, compact, light. Ideal for a pocket rocket.

I am puzzling over how to implement this though, as regards to actually mating the engine to the rear wheels. Having read a number of threads, it seems as though some people turn the engine sideways and use a shaft, but run into oiling issues; others run a chain back to a differential that has a big sprocket attached, but have issues with lubing the diff and anyways a big old chain doesn't seem that attractive an option...

I'm just wondering: is there a FAQ somewhere on these 2 methods, with pros and cons to each, and a parts list? Or is this new ground for a lot of people? Or is there a third, better way?

thanks in advance,

Thaddeus

[trialsmangasgas]

Check out robertwa's posts. He has built a cool Yamaha FJR1300 powered Locost and the engine sits just like it is in the bike. It is shaft drive touring bike. The only issue is that the diff must be flipped over and run upsidedown. So he has a pump circulating the fluid around. He just got it licensed so he has not put a lot of miles on it yet. He is a good guy and should answer any questions you may have. Russ

[KB58]

FWIW, it'll have oiling issues regardless how it's mounted, due to the car not leaning like the bike does.

[robertwa]

Thaddeus,
Welcome to the site!
You already mentioned the likely configurations. Most common is the engine mounted longitudinally with a driveshaft adapter bolted on in place of the bike sprocket. There are many cars built this way - some have modifications to prevent oiling problems and others don't. Some engines such as the Yamaha R1 survive with only a slight over-fill of oil, others like the Blackbird and Hayabusa need dry sumping or a baffle plate in the sump (this info is all just from what I have read before, I'm no expert).

However I think it will depend on what you are building and how you are driving. For track day driving using sticky tires it is probably more important to have a modified system than a road car built for spirited driving.

Unless you are building a mid-engined car I think a long chain would be impractical.

[thaddeus]

I'd say the car I build will be used for 'spirited driving about town'. And my town does not include the Nurburgring, unfortunately.

That workaround to flip the differential over was pretty creative. How has it been holding up?

Is there a listing of engines and the rotation of the driveshaft for each? Seems like it would be a pretty handy spreadsheet to have....

[robertwa]

Flipped diff is holding up fine so far, although I have put limited mileage on the car yet.

General guide to bike engines rotations - look at the side of the bike that the chain or shaft drive is on , that will give you the rotation.

All chain drive bikes I have ever seen have the sprocket on the left hand side. When turned 90 degrees in a car the output spins the correct way

Some shaft drives like Yamaha have the right angle drive on the left hand side of the bike. Unfortunately this means the drive spins the wrong way for a standard rear differential

BMW bikes on the other hand have the shaft output on the right hand side, meaning the drive spins the correct way. I think the Honda ST1300 V-4 is the same configuration

[impishsprite]

Flipped diff is holding up fine so far, although I have put limited mileage on the car yet.

General guide to bike engines rotations - look at the side of the bike that the chain or shaft drive is on , that will give you the rotation.

All chain drive bikes I have ever seen have the sprocket on the left hand side. When turned 90 degrees in a car the output spins the correct way

Some shaft drives like Yamaha have the right angle drive on the left hand side of the bike. Unfortunately this means the drive spins the wrong way for a standard rear differential

BMW bikes on the other hand have the shaft output on the right hand side, meaning the drive spins the correct way. I think the Honda ST1300 V-4 is the same configuration

Or you could use a 4WD front axle...

[trialsmangasgas]

On the front 4WD axel, Has any one actually done that and what donnor did they use? I was wondering on Honda CRV's (the 4WD one) , was there ever one that had an engine that rotated the wrong way and used a rear diff that would rotate the right way for a BEC?????? Just brain storming or more like drizzling. Russ

[robertwa]

On the front 4WD axel, Has any one actually done that and what donnor did they use? I was wondering on Honda CRV's (the 4WD one) , was there ever one that had an engine that rotated the wrong way and used a rear diff that would rotate the right way for a BEC?????? Just brain storming or more like drizzling. Russ

Russ,
I wondered about that, and also the about the Civic wagon AWD, but never followed up to find out.

FWD diffs are a good idea too, but could also suffer from oiling issues since the ring gear will be spinning the opposite way in a rear configuration, and the oil may nlot get flung into the channels as well.

Of course the easiest way is to stick with the regular sprocket drive engines, R1, GSXR, ZX12 etc since they all spin the correct way. Apparently the R1 makes for the easist packaging in a LHD car due to the sprocket placement

[trialsmangasgas]

Yeah, but an engine in the same position as yours (as on the origional bike) is the way to go IMHO. And RH shafts are rare. I think I'll call a Honda dealer monday and talk to the service mgr. and ask him. He will probably think I am off my nut!!! I don't know how the motor sits in a CRV or the wagon. If it is transverse, I bet the prop shaft rotates just like all RWD's do. Russ