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[feeutfo]

Honda have had this in Motopg for a while, rumored to be coming to road bikes possibly in 2012. Changes gear with zero loss of drive. No need for double clutch gear box such as DSG or the like, can be automatic or manual due to the minimal force needed to change gears.

On bikes it does away with need for gearbox destroying quick shifters that cut ignition spark to allow gears to disengage/engage during loss of drive. Traditionally bikes use angled dogs to pull themselves together as they engage, meaning there must be a drop in drive to shift gears.

Not anymore. Cheap to make, compact, and best of all Zeroshift are a British company.

[media]http://www.youtube.com/watch?v=HJHjiUheod8&feature=youtube_gdata_player[/media]


Xtrac have a similar less compact idea, so I guesss formula 1 have had something similar for a while....?

[Kevin Wood]

Hmm. The way I see it, the speed of the bike cannot change instantaneously. Neither can the speed of the engine, so something has to break if you don't lift off a little during a shift?

Kevin

[feeutfo]

The onboard shots from behind the rider look very similar afaict. Old style quick shifters gave the rider a jolt as the next gear engaged. Something that makes me wince through mechanical sympathy as, if it was my bike, as the gear box would be breaked in 6 months, so I'd retard the shifter timing to give a smoother change. But they get a new engine sooner so who cares.

With this the rider still gets a jolt from what I can see as the taller gear engages. The difference is, the dogs are slid in to the next taller " floating"(?) gear while the drive gear is still engaged. The taller gear takes up the slack, as its taller, and away you go. The jolt is transferred between the gears on a flat surface full on, rather than the old way of angled dogs pulling themselves together meaning the point of the dog wares on the corner with all that drive on such a small area. The slightest ware on those corners/tips of the dogs can give a lot of sift problems on a traditional bike gear box, meaning the gears don't pull themselves together, and no next gear...    WAAAAAABABABAB

[feeutfo]

Should add, ime DSG's give a similar surge, although less abrupt.

[Kevin Wood]

The slightest ware on those corners/tips of the dogs can give a lot of sift problems on a traditional bike gear box, meaning the gears don't pull themselves together, and no next gear...    WAAAAAABABABAB

Whereas, on this box, if you have the 2 gears engaged for more than a nanosecond, the whole transmission locks solid, and you need a new bike and new underwear, leathers, etc.

I'm sure it would work OK, just can't see how it would make a massive difference except to the physical engagement of the gears since you haven't done anything to mitigate the massive transmission shocks that an instantaneous shift would cause. (Whereas with a DSG gearbox, for example, you have clutches that you can fine tune to compromise between slow shifts and massive wear, albeit they are a pain in the crack in most other respects).

[feeutfo]

The slightest ware on those corners/tips of the dogs can give a lot of sift problems on a traditional bike gear box, meaning the gears don't pull themselves together, and no next gear...    WAAAAAABABABAB

Whereas, on this box, if you have the 2 gears engaged for more than a nanosecond, the whole transmission locks solid, and you need a new bike and new underwear, leathers, etc.

I'm sure it would work OK, just can't see how it would make a massive difference except to the physical engagement of the gears since you haven't done anything to mitigate the massive transmission shocks that an instantaneous shift would cause. (Whereas with a DSG gearbox, for example, you have clutches that you can fine tune to compromise between slow shifts and massive wear, albeit they are a pain in the crack in most other respects).

It is minimal advantage, but for racing,  race simulations show 1.5 seconds a lap advantage. Over a race distance that's a different world. 

For road bikes, or anything else for that matter the clutch can still be used, it's still there they haven't done away with it, as is the Cush drive in the rear hub. You can ride sensibly, or get angry and just kick the lever, don't even shut the throttle.

[feeutfo]

Plus the back of the dogs in the video are angled, so disengage themselves.

[Kevin Wood]

I guess the proof of the pudding..

Nice to see someone working on a simple, elegant solution to a problem rather than trying to shoehorn 2 of everything in like DSG. Less is more...

[feeutfo]

I guess the proof of the pudding..

Nice to see someone working on a simple, elegant solution to a problem rather than trying to shoehorn 2 of everything in like DSG. Less is more...

Indeed, it's so simple... And all that.


They have designs from scooters to Trucks, can add a double clutch if needed for refinement on autos I guess...? Would it need double clutch? I've run out of brain. 

[feeutfo]

Some bumpf

http://www.zeroshift.com/assets/pdf/Zeroshift%20AT.pdf

[TheBoy]

I just accept that my poor old Kwaka won't do 1st to 2nd at anything above 40mph, double clutching or brute force...

[feeutfo]

I just accept that my poor old Kwaka won't do 1st to 2nd at anything above 40mph, double clutching or brute force...

I had my zx6 gear box apart, very poor from Mr Heavy Industries. It looked like the crank case wasn't lined up correctly when they machined it, everything was off/twisted.

Time for a new/other one J. Zx9 c1 or 2 I reckon. 

[TheBoy]

I just accept that my poor old Kwaka won't do 1st to 2nd at anything above 40mph, double clutching or brute force...

I had my zx6 gear box apart, very poor from Mr Heavy Industries. It looked like the crank case wasn't lined up correctly when they machined it, everything was off/twisted.

Time for a new/other one J. Zx9 c1 or 2 I reckon. 

Or just change gear before about 8k rpm in first...  ...helps keep the front down as well.

Wouldn't mind having the gearbox apart, I have an annoying oil leak from gear change shaft.  But I haven't got the first clue where to start

[Martin_1962]

I guess the proof of the pudding..

Nice to see someone working on a simple, elegant solution to a problem rather than trying to shoehorn 2 of everything in like DSG. Less is more...

To me DSG looks like a bodge

[feeutfo]

I just accept that my poor old Kwaka won't do 1st to 2nd at anything above 40mph, double clutching or brute force...

I had my zx6 gear box apart, very poor from Mr Heavy Industries. It looked like the crank case wasn't lined up correctly when they machined it, everything was off/twisted.

Time for a new/other one J. Zx9 c1 or 2 I reckon. 

Or just change gear before about 8k rpm in first...  ...helps keep the front down as well.

Wouldn't mind having the gearbox apart, I have an annoying oil leak from gear change shaft.  But I haven't got the first clue where to start

Depends on that model, but usually lump out, turn it upside down, remove the lower half of crank case etc. Remove the gears on their shafts and find the damaged ones,or any bent/worn selector forks, re fit.

As an example, gears can range from £120 to £60 per gear depending,on a gsxr 1000 01-04. Plus you need your shims doing, and carb needles and jets most likey will be worn too. Cam chain? Clutch wear....?   I'd balance that lot against a lower miles lump tbh, seeing as the engine needs to come out anyway.