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[zap mc]

just watched the video and it was very impressive. The wheelbase was lengthened by 7mm to improve handling and the seat was positioned 30mm closer. These are the types of design perameters that are way out of the league of Zero. The Ducati is a production motorcycle designed from the ground up, the zero is more of a parts bin project bike and not in the same league at all.
I remember discussing rear shock sag setup with the EU main agent who tried to tell me that if you changed the preload that it would void the warranty.

[Marshm]

Sure it might be desired to have no engine breaking in some situations.  However, when quads started to use snowmobile transmissions beyond just Polaris, they received many complaints about not having engine breaking.  So now they added engine breaking to just about all of them.  I guess it depends on what you are doing whether you want engine breaking or not.  It certainly doesn’t appear people think it is always bad.  I have been known to reduce throttle and use engine breaking to slow it down a bit.  Down hills in rough offroad I often use it. 

[gasdive]

 It certainly doesn’t appear people think it is always bad.    

It's really only people who ride close to the edge of control that think engine braking is always bad and in every situation.  It's fine if you're in traffic and you just want to slow down a bit.  Riding down a steep hill off road or riding into a corner on the tar as fast as you can engine braking is *always* bad.

I used to crash my brains out down hills when I first switched from twostroke to fourstroke.  Everyone told me to just pull in the clutch and I'd be fine.  It was one of the hardest things I've ever done, the brain just didn't want to do it.  

Finally I did and suddenly hills that I'd been *terrorfied* of were no problem.  They were just as easy as they'd been on the twostrokers.  Suddenly I could ride down loose scree slopes that were right on the point of landslide without a care.  I could change lines and jump in and out of ruts as I chose.  

Now I see people picking their way slowly down hills and falling off I say "just pull in the clutch".  They can't do it any more than I could.

On road or off road, engine braking is *never* a good thing.  It destablises the bike just when you need the stability the most.  Without it you can carry *far* more entry speed into corners (both on and off road).  The suspension remains more supple and follows the ground better giving you more mid corner speed.  You can brake harder and later on the front.  The front grips better giving you even more corner speed.  When you get back on the power there's less transition shock so you can get back on the power earlier in the corner, apply more power and come out of the corner much harder.  

All of that applies to both on and off road.  

Here's what racers think about engine braking: http://www.sigmaperformance.com/slipperclutch.html

The slipper clutch is still just a coverup for the basic problem.  Look at the last ever GP where twostrokes competed.  The 990 cc fourstrokes were something like 60 km/h faster down the main straight at Phillip Island than the only 500 cc twostroke in the field.  Yet the twostroke was able to get pole position.  (well ahead of Valentino Rossi).  There's no way he could have won the race as the fourstrokes streaked ahead down the straight then just blocked the road around the corners and indeed in the actual race, despite starting on pole he was last by about the 4th corner.  

The fact however remains, that without engine braking, the much slower bike was able to lap much faster.

[manlytom]

yeah - good points gasdive. Hence I was proposing a handlebar controlled engine breaking. So you can slow down the bike on demand. Especially commuting you have a lot of stop starts or come up to a red traffic light. In addition to cruising to a halt whenever possible I have been using the brakes a lot (great on the 2011 now) - for that I could have done with engine braking to top it up.

cheers
Tom

[gasdive]

Tom you're exactly right.  I think a controllable regen would be great and it could be much stronger than any "automatic" regen.  Personally I'd like it as a left hand lever, but of course preferences would vary.

The ideal would be a frontwheel regen but it would be *very* difficult to implement.  Swigz has done it but it's left no room for batteries!

Perhaps something a little less complex would be good.  Maybe a telescoping shaft from the front wheel to a generator mounted on the top part of the fork or triple clamp.  (so it's unsprung)

Still for the extra weight you could just have some more batteries.

=:)