car build

One thought is it could be done the chain drive to a transaxle....but would involve alot of fabbing. Another thought would be to use a shaftie like a GW engine or Beemer, left in first gear and only use the transaxles gears. Or go way weird and use both trans' gears and what 5X4 or 5X5 gears to play with. You could end up with 5 or 6 speeds in reverse.

All wheel drive seems such a baaaad idea.

Why?

Presumably you are after a light efficient vehicle?

I'd adopt Dels famous philosopy of 'wrong as quick as possible' (rather than 'right first time'.)

Get something quick and simple built first .... you will learn soooo much. Then you can build the mk2 which will be how you really want it.

Good luck and have fun

Del

If you are determined to have all wheel drive, try looking at 4-wheel ATVs and see how they do it. It might be exactly what you want (or a slightly beefier version thereof).

First, I don't know how well the engine will cope with added torque, as most m/b engines are designed to move a small weight fast.

Have you looked at a small 4WD offroader for ideas/components?

Suggestion: do not design the vehicle to work (just) without passengers, then expect anywhere near the same performance once loaded. (as a rough guide, a 2.5l petrol car is more economical than a 1l, with a half-ton payload).

smc

I have built a few Three Quarter Midget race cars and they weighed in at around 700 pounds with a 750 cc Yamaha FZ750 m/c engine. We ran a stock engine to its rev limit 11,200 rpm on about 20 consecutive saturdays under full racing load on quarter mile paved ovals in 100+ deg F temps approx 40 hard laps per night. We then pulled the same engine out and put it in a snowmobile for approx 10+ more weeks in the dead of winter at -15 deg F temps. When we pulled the engine apart (for no reason, other than to freshen it up) the engine builder said it was like new inside. The engine already had 23,000 kms on it when we got it from a hard driving motorcyclist who happened upon a deer too quickly. We mounted the engine 90 deg from its position in the bike frame, so that the output shaft on the transmission was facing the rear of the car. A specially made hub was made with a spline matching the output shaft spline, and included a mounting flange for a driveshaft yoke. From the hub to the rear ring and pinion axle we used a driveshaft with a built in slider to compensate for fwd and bwd motion of the rear suspension. This configuration is bullet proof, in fact the only problem we had in the driveline was tearing out a pinion gear in the rear end. Since this time the racing club we used to race with (Can Am Midget Club ; see website) has been ongoing with these exact drive arrangements but with now even more HP than ever. You may want to check with some of the guys racing them now, but my understanding is that the transmissions are pretty bullet proof. As for AWD, I would say if you can find a transfer case out of ???whatever and run a similar driveshaft set up as I mentioned earlier, I see no reason why if you had a differential in the front and back of this car, that you couldn't run AWD. You probably should go to the biggest m/c engine you can to keep the same relative power to weight ratio that we had 700 pounds to 100 HP. It will be very fast as well, if you can acheive this.

GS

Thank you for the write back. I was wondering if you used the Yamaha's clutch. Also, what kind of gearing did you end up with. Was it low enough to be a daily driver.

Thank you for the write back. I was wondering if you used the Yamaha's clutch. Also, what kind of gearing did you end up with. Was it low enough to be a daily driver.

Yes we did use the stock clutch, but it is also possible to get stronger aftermarket clutches. The stock one never gave us any problems, but with alot of stops and starts on the street and hard driving, you will probably want to upgrade. We had a quick change rear end with approx. 3.5:1 final drive ratio and approx 22" o.d. tires. We would typically be using 3rd gear in the trans for a 1/4 mile oval. The speed was probably in the neighourhood of 80+ mph. Keep in mind that in most m/c engines have a reduction of approx 2:1 between the crankshaft and the transmission input shaft, so if you plan on not using the transmission (I feel this is a mistake), then you have to work out the issue of your output shaft being at 13,000+ rpm. Homemade gearboxes are scary and the transmissions on the m/c engines are very strong (including the clutch). If you are considering using another transmission, consider a Honda Civic trans, because there were AWD models back in the late 80's that had everything you would need to go AWD built in. The only problem there is the reduction required again, since these were designed for 6,000 rpm engines.

GS

I was also wondering if you used the chain drive or did you convert to a trans-axle. If you did convert, how. I think it would be really cool to the motorcycle Tranny but I don't know how to link it to a trans-axle. My goal would be to install a 1300cc hayabusa or equivalent m\c engine. I think I would need the larger size engine to offset the weight of the car. The car is NOT a BMW mini. It is an older European Austin mini cooper only weighting about 1320lb with the A series engine it came with ( which I do not intend to use).

The Mini I referred to was from BMC not BMV !!

BMC stands for British Motor Corporation, they were the ones (under the Austin & Morris names) who built the original Minis that took the world by storm in 1959.

They were designed by Sir Alec Issigonis, (deceased 1988). (See Wikipedia http://en.wikipedia.org/wiki/Alec_Issigonis)

The car will not help you much as they suffered rather badly from rust, unless properly conserved by after market products.

It is also steel (hence the rust problem), and heavy, why not go for a lighter and stronger build design of your own?

Maybe you could (for me at least) re-state your aims and objectives clearly again....I seem not to have followed your lines of thought somehow in some areas, sorry!

I have a kit car I built about 8 years ago and dreamed when younger, of building my own car with a motorbike engine and gearbox. The primary problem of them is, no reverse gear.....! But if the car was built very light, that might not be a problem! Many years ago, some very heavy motorbikes had a reverse to help manouvering, whether there is still bikes with such a gearbox I do not know, but some look heavy enough!!!

This link may give you some further good ideas!

http://www.morgan3w.de/

Although built a long time ago, modern up to date versions of this layout are still favoured by some designers! Good steering, good braking and better road holding that a single front wheel....

Honda Goldwings have reverse, using the starter motor for minor distances [parking stalls].

What I was looking to do was build a fast light all wheel drive street legal car. Originally, I thought I wanted to put a street bike engine in it but with mire research and everyones very necessary input, I have decided that is under power and very complex to end up with awd. So, I think the best route to go is trying to fit a sti engine and awd drive train in the mini. The other advantage is the fact that it is a flat four. That will be the big advantage to fitting an engine in this little car. All said and done, hopefully I will end up with a 300+ hp 1500 lb or so car. I REALLY appreciate everyones input. I would certainly like to know exactly the best option before I spend so much time and energy and money on such a project.

Thanks for the explanation. Best of luck.

Now you're cookin' - but ditch the mini and put the Scooby stuff in back to front. Then you'd have a proper mid-engined layout. In fact you might not need the WAD!

A drive shaft shop could help you adapt from the shaft that a gear or pulley would be mounted to. I used to have them made for custom machines and prototypes. Also not all Bikes use that kind of system, some are shaft driven. I believe the Goldwings are. Honda shadow i think was ... back in OH mid 80's. Don't remember the year, buddy had one.

Don't use the clutch, on the bike motor. come right off the primary shaft mount a duplex or triplex sprocket, support the end of the shaft w/a bearing. A harley [or s&s]motor would be easy, since the transmission & motor are separate.

on the transaxel side, you'll need the flywheel & to build short shaft to mount the sprocket & some sort of support for this short shaft.

You'll have to figure out how much faster the motorcycle motor spins & use the sprockets to reduce the speed [probably 3:1 or more] this will increase the torque. You probably only need a top speed of around 70-80 mph.

First try two wheel drive , you didn`t mention engine capacity ,power , most probably you try to pull the car with equlent bike if it works to your expectation ? go ahead and couple engine (perpendicularly) through modified gear ratio , clutch system , you will rather decrease the weight of the vehicle considerably , all wheel drive needs complex mechanicals , see for ATV`s through google

If you are a first class Engineer with lathe & milling experience, the equipment, the metallurgical knowledge and the metals as well..... you might get it working, but you have got a hard pull for the next 3 years or even more, especially if you have a family......setting up of 4 WD is a pain without the complication of a motor cycle engine conversion..........

Why do you want to make something with 4 WD anyway, is it for off road, if yes, go and buy some bashed up 4WD car and use its components, forget the MC engine.....

If you want a light but fast road car, easy to build (relatively!) go for a three wheeler with a single rear wheel and forget 4 WD....you can fit your engine and rear wheel drive from your Motorbike.....and get good braking and handling with two front wheels. Look at all the Morgan three wheelers that were built over 60 years ago!!!!

The front end can parts come from a light car and use the brakes and steering. (Never build a trike with a single front wheel, you cannot steer single handed for more than a few seconds as the weight of your arm starts pulling a curve and braking in the wet is like a bad bike!!!)

I wish you well and I apologise for being so negative, but you may be biting off more than you can chew if you do as you stated......

See Blink's Project on a different thread. If you want a easy economical runabout, if you are looking for a off road, buy one yamaha makes some dandy 2 seaters. As Andy suggests use the running gear out of a old 4 wheel drive, if you just have to build something your self!

Hook a generator to the bike tranny ... probably 3rd gear and mount electric motors on each wheel. or use 2 identical trans-axles (standard and in the same gear) and mount a elect. motor on each axle. The limited slip in the axles will account for any minor strain in the motor when turning. Couple of bat. for a kind of an accumulator. Remember if its an air cooled motor that most cars don't have adequate airflow under the hood to keep it cool and they use hot water to run the heater ... so get one thats water cooled or build a heat exchanger to go on or around the head. .... Have fun.

The hot exhaust can be used to warm water for a heater if you are going to use an air cooled Motorbike Motor, but I would recommend a 4 stroke water cooled engine, they usually live longer because they can be built to closer specs and are kept well within a predetermined temperature range. (unless something goes wrong of course!

But you might have problems ducting enough air to an air cooled motor anyway....too much and the engine runs too cool, too little and you have overheating and wear problems....

Water is quite a nice cooling media and you can also have a gauge to let you know the actual temp and warning lights with very little extra effort! Plus you can keep your feet warm with a small heater using the hot water circulation!

So my money goes on a water cooled, 4 stroke engine with the biggest meatiest clutch that comes as standard, or can be easily uprated with after market bits and pieces. A "Big Bike" engine with a separate gearbox such as Orange County Motor Bikes use might even give you even more clutch options and that nice wide rubber toothed belt that they always seem to fit on the TV programs, to drive between the two, that runs quieter than a chain.....its so massive, I am sure that it will handle all you can give it!!

One last point about 4 WD, it costs fuel to run it, that is even if you can disconnect it on the road, the hardware is still there and the weight.

Do not forget that with a trike with two wheels at the front, there are a great many different car front ends, including also the gearbox and axle all in one relatively small unit, you could even have a diesel from a VW or similar.....economy pure.

Wow, you guys all have great ideas and I apologize for the lack of details. This is the first time I have ever used an open forum like this. What I am trying to do is install probably a 1300cc newer water-cooled engine. The car is a 70's mini cooper weighing hopefully less than 1400 lbs. The reason for the 4wd is for traction. This is definitely a street car. My hope is the engine will have at least 230 hp. I know I could put say a b18 or equivalent 4 cylinder car engine with 220hp in but I think the m/c engine would give me much less weight per hp. I also think I would gain great advantage with the rpm range of a m/c engine (15000 and higher). However I do realize that I will have to gear it down considerably, but thats ok considering the m/c's top speed is over 200mph. I'm not looking to go much over 100 in this little car. You all have mentioned ATV trans-axle. Do you really think they'll hold up to the abuse of 0-100 hard acceleration, even clutch "dropping". Thank you all for all your advice.

P.S I am very blessed to have access to a shop with machine lathes, mills, and iron workers for what ever I need to make in the way of adapters.

1400#'S is @ least twice the weight of a 1300cc motorcycle, so holeshots will definitly going to be hard on a moto clutch.

minimum weight for a midget is 900#'s & there aren't alot starts & stops in a 50 lap main.

But still keep all us motor heads informed, Sounds like a fun project!

You may find this all a bit negative, but I did know the BMC "A" Series motor well when I was much younger and you would be advised completely against tuning for more than 100BHP......

The BMC Mini engine is not the way to go as I believe strongly that it is most probably an "A" Series motor (That was all that was ever fitted to Minis).

If true it has only 3 main bearings, is extremely heavy for its capacity(cast iron) and will most likely have a cast iron head as well.....there were some after market alu heads around.....but this is not the place to start tuning.

Going to the BHP you are talking about is probably not worth the effort as the life of the engine would be very short and expensive....

I know this engine well......it started life in the 1950s and was originally a side valve engine (803cc if I remember correctly), later it was OHV, but the block remains the same with a side mounted cam shaft....They were bored out to around 1300cc by BMC and private owners could take some blocks to a max of 1360cc if I remember correctly, with a long stroke crankshaft....

We tuned them a bit in the 60s and the first part that breaks is the crankshaft with anything over 6000 RPM, There were special cranks made the 60s & 70s of steel, you would need to try and find one of these if it is not already fitted from a previous owner....I doubt if anyone still makes them as this engine has already gone to the Engine heaven......

They lasted forever in their original forms and not over revved. Some have clocked up over a 1,000,000 miles....when looked after.

If you want power, look for something better.......the "small block" all Aluminium 3.5 liter V8 from the Rover V-8 (early 70's) is a better bet, lighter than the mini engine and can be tuned without a Turbo to around 300BHP. With Turbo, the sky is the limit with. Very strong and difficult to burst!!

But I am a bit old fashioned and I am sure that you will find other engines equally good, especially with less capacity, that will tune up well.....

Checkout the following web site for BMC A Series Engine for all the official designs sizes and power outputs etc., none exceeded 100BHP if I remember correctly:-

http://en.wikipedia.org/wiki/BMC_A-Series_engine

The long stroke versions are to be avoided completely when tuning as they had even less tolerance to high revs than the others....so you would be limited to a later 998 Extra motor......which you don't have as it came out in the 90s I believe.....but still very heavy!!

I wonder if you could salvage and modify the drivetrain from a John Deere 4x6 Gator tractor. It uses a centrifugal clutch mechanism, but I bet you could figure out a gear lockup of some sort, and it has 4 drive wheels you could modify maybe with longer axles and torque tubes, and it basically runs on a lawnmower engine, so adapting a bike engine into that should be somewhat trivial.

Are you really sure you want to do this with a Mini? Going the wrong way if you ask me especially if youre talking overweight BMW Mini! I'd start with the Mini engine and try to do the vehicle properly, i.e. lose 60% of the mass. Mini engine then becomes more than twice as good!

Fabricated aluminium monocoque (or CFRP hand laid-up in shed) Fabricated aluminium suspension, or slender steel tube for ease (welding etc). NOT huge fat overwieght wheels and tyres, maybe 3 wheels a-la Blink.

I agree with most of your post completely, especialy i layout etc..

But I personally feel that a more than 50 year old design of motor, fairly welknown that it gets quite delicate at 6000 RPM or more, with a decided handicap in weight (cast iron) and maximum performance tuning 100 BHP for safety, (although I have to admit that private people have managed a better output to around 130 BHP, but reliability as well?) is not really what he needs.....

I personally liked his original motorbike engine idea (the mini engine idea came later) as there are some really fantastic engines with masses of BHP, with water cooling and relatively lightweight around.....for many years too....

Going for track performance (Jedi, OMS style)) the motorcycle unit is tremendously efficient in terms of power/weight. Pulling a load of lard? I think too little torque and too many gears reqiured. Bore/stroke yer A-series to 1400cc and fit a supercharger!

"Looking for a team for the automotive xprize" is one such discussion. I have also expounded on others, such as "air car".