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BEC gearbox & shifting
bassett - 19/2/15 at 08:11 PM

Hi,
my R1 engine is currently away having most of the gears replaced as it was popping out of 2nd and the rest were found to be a bit worn. The bills are definitely stacking up so when it comes back i want to try and be a bit more sympathetic on the gearbox(even if it only lasts the first blat out) as im not always spot on with the shifting.

So any advice on optimal shifting/my current approach?
At low revs clutch down and pulling the lever hard for 1st to 2nd. Id also change 2nd to 3rd with the clutch if i cant get space in traffic to accelerate and clutch-less shift
At high revs im shifting clutch-less pulling the lever forward slightly then lifting off the accelerator and then pulling the lever all the way to shift into the next gear

Also what is the average expectancy of these parts in a bike and BEC?

Thanks
Adam


daniel mason - 19/2/15 at 08:20 PM

What about a closed loop setup? A bit pricey but in my opinion,with an expensive car and motor is the way forward!
That's the route I'm taking with the force and so far it's a similar cost to a flatshifter setup!


theprisioner - 19/2/15 at 08:24 PM

"What about a closed loop setup? A bit pricey but in my opinion,with an expensive car and motor is the way forward" can you explain about "closed loop setup"?


daniel mason - 19/2/15 at 09:20 PM

I can indeed!
Basically a flatshifter or any of the electronic systems cut ignition for a set time (say 50ms) before restoring power to the coils. The flatshifer then 'hopes' it's found a gear during that time and restores power.even if it's not in gear!
A closed loop setup uses either a sensor on the gear barrel which will only restore power when the shift has been made, or by magnetic sensors on the actuator itself so that it knows when the shift actuator is at full travel and therefore shift is made!
Some ecus have the function to do this otherwise it's a call to David loomes at xoomspeed in Scotland! ( that's what I've e got)
Other functions it can do are automatic up shifts at pre determined rpm's in individual gears, full throttle upshifts, and blipped clutch less downshifts,

[Edited on 19/2/15 by daniel mason]


ReMan - 19/2/15 at 10:53 PM

Technique wise I think your spot on,
I always clutch on downshifts


Johneturbo - 20/2/15 at 04:21 PM

Adam
I've just fitted a "factory pro shift star kit" over winter, this is a thread i found after i bought/fitted it.

http://www.locostbuilders.co.uk/viewthread.php?tid=169084

i've not tried it yet, as i took the engine out to make it easier to fit, it sits behind the clutch basket. but all the bike guys that do trackdays say it's an improvement.
http://www.factorypro.com/Install_pages/Install,EVO,Kaw,zx14.html


Sam_68 - 20/2/15 at 06:13 PM

quote:
Originally posted by ReMan
Technique wise I think your spot on,
I always clutch on downshifts


Yep, you're doing it right.

The alternative and equally acceptable method for upchanges on car dog boxes is to again apply light pressure to gearlever, then depress the clutch just enough to let relieve the load on the dogs, so that the next gear will engage. This way doesn't seem to work quite as well on BEC's though, presumably because the you get more drag from a wet, multiplate clutch than you do with the single plate dry clutch in most cars.

Unfortunately, the dogs in a typical bike gearbox are dainty little things compared to the big, beefy dogs in a box that's been designed for the weight and grip of a car, so you have to expect them to be rather less robust.