Electronic Circuits and Projects Forum

You have the obvious problem of finding a low voltage three phase AC supply to feed it, so what would be the point?.

An typical auto alternator generates a current of about 50-70A so a 3-phase inverter to drive it would be large. That amounts to about a horsepower at 12V. Since alternators operate at high speed (2-3 times engine speed) their torque output would be relatively low as compared to a standard electric motor.

Automotive GENERATORS used to be used on the International Cub Cadet lawn tractors of the mid-1960s as both a generator for battery charging and as the starter motor for the 7-10 hp Kohler engine.

I can't imagine trying (or wanting) to use an alternator as a motor because of the 3-phase problem.

Dean

Originally Posted by Dean Huster

Automotive GENERATORS used to be used on the International Cub Cadet lawn tractors of the mid-1960s as both a generator for battery charging and as the starter motor for the 7-10 hp Kohler engine.

The Yamaha RD200 two-stroke twin did the same thing, it used a dynamo rather than an alternator, and used it backwards as a starter motor.

A friend of mine had one, and actually stalled it on his motor-bike test (big no no), but because it has no need to engage like a normal starter motor he restarted it instantly without the examiner noticing

Interestingly, three or four other friends borrowed his RD200 and passed their tests on it as well, it was a really nice bike to ride, and went like a rocket.

The Yamaha RD200 two-stroke twin did the same thing, it used a dynamo rather than an alternator, and used it backwards as a starter motor.

Actually it was preceeded by the Yamaha CS3 which had the same setup.

Yup, it was a shunt wound dynamo or a series wound starter motor...I had a P reg one,....The regulator doubled up as the starter contactor.

Tuned mine up and had just over 100mph on it! (on the clock of course..)

Originally Posted by Chippie

Tuned mine up and had just over 100mph on it! (on the clock of course..)

At the time I had a 350cc Suzuki, another two-stroke twin, and one night we left our local pub and went down to Bakewell (where the tarts/puddings come from) - we both had pillion passengers. Going into Bakewell there's a nice long flat road, and we were flying

As you reach Bakewell you hit a 40mph speed limit, so I slowed down as we entered it, but my mate Alan didn't - he flew past me, giving it so much thrash on his RD200 that both exhausts were on fire, with pieces of burning carbon bouncing down the road behind him. One way to de-coke the exhausts

RD200's really shifted, they certainly wouldn't be far off 100mph.

Incidently, he bought it on the recommendation of Mick Andrews (multiple world trials champion) who lived in the same village, and was a works Yamaha rider. Alan picked it up brand new, rode it home (about 15-20 miles), and took it to show Mick. Mick jumped on it, wheelied it the entire length of the main street and back again - on the back wheel all the time.

Originally Posted by Hero999

They were two strokes though, yuck.

Great performance from two-strokes!

They might be fast but they're also noisy, dirty and thirsty. Get a 600cc four stroke, same performance if not better, cleaner, quieter and half the fuel cost.

Certainly two-strokes are much more thirsty, that's where the power comes from - but they are also much lower revving.