Automatic motorcycle trannies?

[vifferman]

Interesting Yamaha have developed the 2 Trac versions of their dirt bikes that drive the front wheel by hydraulic drive. Now that would be one way to get the fully variable drive at constant engine speed, just have a computer control the oil supply valves while the engine keeps pumping the stuff.

So far they are still using chain drive to the rear but it suggests that it would be easy to drive the back wheel hydraulically too. (Just like a lot of large machinery)

That thing actually worked really well; if the back tyre started to spin up, the front got more drive and started pulling the bike, transferring weight and stopping the wheelspin.
A fully hydraulic drive would have to be lighter and/or more reliable than chain or shaft drive to be worthwhile, because there would no doubt be some power loss due to slippage, heat, blah blah blah...

[Paul in NZ]

I think (rarely) that the Moto Guzzi "Convert" was the only really successful automatic motorcycle ever made. Even then, it was not really an auto, just a 2 range manual box (low = town, High = country, don't shift on the fly if you want the clutch from a 160 stornello to last) with a whacking great torque converter. I know of one up our way (I did offer to buy it) and the one for sale on bikepoint so at least 2 in NZ.

They can reach about 105 mph and can be fired off the line like a missile (well a GUZZI missile) by dropping it into low, holding the brakes on hard and revving the bejezzus out of it until steam and smoke boil out of the tranny, let of the brakes and away you go... Cor!

The cops in the US bought heaps. If you look on the swingarm of a late 70's tonti framed Guzzi you will notice an extra lug for a disk caliper. Joe law would puull you over with his guzzi plod mobile (how he kept the lights, the radio and everything else running with the weedy alternator is a mystery). Throw out the special side stand which would put on the park brake (hence the special caliper)

If you tried to do a runner in your 'Dukes of Hazard' replica, johnny law would leap on the Guzzi (engine still chug chugging away on a lazy southern afternoon and simply dial in the power after you. No messin with gear and the clutch.... Cool eh!

One bike crazy not mentioned was triumphs 'Slick Shift'. A face cam in the gearbox operated the clutch throw out when the gear lever was pressed down. You could (in theory) idle in gear (assuming your Triumph would idle) with your foot on the lever. Let the lever up and ride away. No need to use the clutch during shifting either.

It was NOT popular and is generally disconnected. Cool idea though...

Paul in NZ

[Mongoose]

I think (rarely) that the Moto Guzzi "Convert" was the only really successful automatic motorcycle ever made. Even then, it was not really an auto, just a 2 range manual box (low = town, High = country, don't shift on the fly if you want the clutch from a 160 stornello to last) with a whacking great torque converter. I know of one up our way (I did offer to buy it) and the one for sale on bikepoint so at least 2 in NZ.

Paul in NZ

One lives in Dunedin.

[Motu]

We put the slickshifts back in our pre units - as we got the power up with late model parts and the odd 11.1,wild cam and big carbs stuff they were so wound up with stiff clutch springs we had Pop Eye left arms and clutch cable life was weeks (specialy with our cable skills) the slickshift took the load off the cable - a few puzzeled looks when we did a clutchless start too!

[moko]

Dutch car maker DAF used to make little run-abouts with automatic transmission consisting of belts and pulleys .They were really popular in Holland but didnt catch on elsewhere.To prove it worked they ran a couple of F3 racing cars with it fitted fairly successfully and Williams tested a similar system for their F1 Car.The FIA banned it in 1994,probably because they were shit-scared it might lead to over-taking or something.Daf were later bought out by Volvo and concentrated on commercial vehicles.

[moko]

The cops in the US bought heaps.
Paul in NZ

Yep,heaps of crap with Harley badges on the tank

[Paul in NZ]

Oh course....

Choosing 'some' bikes automatically makes you a trannie.....

Paul N

Tassels anyone?

[Motu]

The DAF transmission is still around,these days called CVT or some such badging on cars - they were horrible in small cars as first used,but the ones out now seemed to go well - hugely expensive to repair.

Jap scooters sometimes have them too - centrifical expanding pulleys,like all stupid ideas it works.

[scumdog]

Yep,heaps of crap with Harley badges on the tank

Funny how no other company had the business smarts to make that sale

[Paul in NZ]

Funny how no other company had the business smarts to make that sale

Yeah! Must be as hard as heck to sell HD's to increasingly paranoid american police forces.....

Imagine chasing even an old munter like my Guzzi on a bloater glide with extra crap tacked on.. Yikes!

Paul N

No need to chase me, just follow the trail of parts...

[scumdog]

Yeah! Must be as hard as heck to sell HD's to increasingly paranoid american police forces.....

Imagine chasing even an old munter like my Guzzi on a bloater glide with extra crap tacked on.. Yikes!

Paul N

No need to chase me, just follow the trail of parts...

What do you mean by "increasingly paranoid" and how does that influence what bike they buy? as a non-sequetuer that comment rules supreme.

Yank cops have being using H-D since year dot, some have flirted with other brands for a bit and others still use Kwakas etc, "different strokes for different folks"

As I've mentioned before, the trade-in value is a major influence in the bikes they use, more so than alleged patriotism and/or reliability/performance.

Have a nice day y'all

[pete376403]

The DAF transmission is still around,these days called CVT or some such badging on cars - they were horrible in small cars as first used,but the ones out now seemed to go well - hugely expensive to repair.

Jap scooters sometimes have them too - centrifical expanding pulleys,like all stupid ideas it works.

CVT - Continuously Variable Transmission. Incidentally, The Zenith Gradua had a variable transmission way back in the 10's or 20's or thereabouts. The expanding mechanism was controlled by a hand lever, but the principle was the same. IIRC it was so successful in the TT (compared to the fixed gearing that most other bikes had) it was banned. Thereafter the Zenith logo was an image of a five barred gate (ie barred from cometition). Or I might be thinking of the Rudge Multi.

[pete376403]

Funny how no other company had the business smarts to make that sale

Not so much business smarts as a protected market and the police specification tailored expressly to suit one brand of bike. Ducati tried to break into this market with the Apollo V4 but the bike made too much power for the tyres, which the police specification stated had to be of one particular size only.

[Morepower]

Automatics

Have not found a modern one in a car I like . Much rather drive a manual and they certainly have no place on a bike in my opinion unless its a electronicaly shifted full manual box that shifts when you push the button not 2 seconds later when you are in all sorts of trouble.

My 2c

[Morepower]

.Rover had a ''freewheel'',a fancy version of Maori Overdrive - wind a big knob and it would coast when you throttled off,so you could make clutchless shifts....down hills in a very overweight Rover 90 with drum brakes in ''free wheel''

Been there not much fun on a steep gravel road

Dave