Ferrino
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| posted on 21/1/07 at 11:09 AM |
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Downshifting Technique
I'm still pretty new to bike engines and gearboxes and was wondering what the best technique for downshifting is?
Forget heel-and-toe for the moment, let's say you are just conventionally using your left foot on the clutch and right foot on the brakes, as
you would in a boggo tintop. This is the way I have been braking so far and it seems to work fine on track - if I am going all the way down the box I
always 'engage' each gear, rather than banging down in 'batches' of gears (eg. 6th straight to 2nd). I read somewhere
that this conventional shifting could result in rear-wheel locking due to engine-braking, but I have never experienced this and it seems to work fine,
you just get the accompanying rise in revs from changing down a cog. Maybe it's because I tend to downshift quite late - ie. at slower
rear-wheel speeds?
So is this how everyone else downshifts? I'm not brave enough to try heel-and-toeing just yet 
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Wadders
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| posted on 21/1/07 at 11:14 AM |
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changing down like you would in a car, i.e using engine braking, is not so good for bec's it puts a lot of strain on the box. I try to avoid it
as much as possible. Its ok if your not going too fast mind.
Originally posted by Ferrino
I'm still pretty new to bike engines and gearboxes and was wondering what the best technique for downshifting is?
Forget heel-and-toe for the moment, let's say you are just conventionally using your left foot on the clutch and right foot on the brakes, as
you would in a boggo tintop. This is the way I have been braking so far and it seems to work fine on track - if I am going all the way down the box I
always 'engage' each gear, rather than banging down in 'batches' of gears (eg. 6th straight to 2nd). I read somewhere
that this conventional shifting could result in rear-wheel locking due to engine-braking, but I have never experienced this and it seems to work fine,
you just get the accompanying rise in revs from changing down a cog. Maybe it's because I tend to downshift quite late - ie. at slower
rear-wheel speeds?
So is this how everyone else downshifts? I'm not brave enough to try heel-and-toeing just yet
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TimC
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| posted on 21/1/07 at 11:20 AM |
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Heel & Toe
Practice in your tin-top and find a comfortable method. My feet naturally 'toe-out' so coventional heel-toe was very awkward for me.
I've taught myself to brake with my heel and dab with accelorator with my toe. Been working at it since I was 18 (8+ years) and am now
relatively effective. Natural part of my driving now. Pays dividends in any RWD car since matching engine revs greatly reduces risk of locking-up
when coming down the box. This results in spinning - as I can testify.
Practice practice practice. (currently working on double de-clutch for the distant day I buy a Ferrari 308!)
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DIY Si
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| posted on 21/1/07 at 04:42 PM |
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Same here. I can't comfortably turn my foot enough, but having size 12/13 feet means I can bridge the pedal gap ok and use both edges of my
shoes, rather than heel/toe.
“Let your plans be dark and as impenetratable as night, and when you move, fall like a thunderbolt.”
Sun Tzu, The Art of War
My new blog: http://spritecave.blogspot.co.uk/
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SixedUp
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| posted on 21/1/07 at 06:14 PM |
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Not trying to be confrontational, but never having driven either a bike or a BEC, I'm curious: why do you want to be using any engine braking at
all? Why not just use the brakes to slow down (ie with the clutch engaged), and then directly engage the appropriate gear to allow the engine to
speed you up again?
Cheers
Richard
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JoelP
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| posted on 21/1/07 at 06:21 PM |
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you waste a fractin of a second coming off the brakes and going onto the throttle, the alternative is to crack it through the gears and use the clutch
to rev the engine up, but thats not very sympathetic on the clutch, nicer to raise the revs whilst you are still braking and spare your clutch a
little.
When i was tracking a CEC i used to use the engine braking (as it reved up into the gear of choice) as the final part of the braking into a sharp
corner (if the car is already drifting slightly into the corner then engine braking is nicely enough to finish the braking off as you move your foot
across to balance the throttle through the corner), a bec doesnt have enough engine braking to do this. If you can heel and toe you have more
flexibility.
Must say thats all IMHO, and i never mastered the BEC as well as i did the CEC.
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ChrisGamlin
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| posted on 21/1/07 at 08:08 PM |
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The technique I use on track is to do most of the braking first whilst staying in the same gear, then banging it down several gears just before
turning in. This means the revs are always low so there's no chance of a rear wheel lockup, and again because the revs are low there's
less stress on the clutch etc.
If you can master heel/toe then obviously thats better, but its something Ive never really got round to trying in anger. I can do it when tootling
around town etc, but not yet got the confidence to do it when requiring maximum retartation into a tight hairpin on track!
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DIY Si
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| posted on 21/1/07 at 08:22 PM |
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Pretty much the same here too. Going slowly (ish) I'll heel & toe. Pushing on a bit I tend not to due to being a bit scared of breaking the
clutch diaphragm again. Most BECs tend to use the clutch as little as possible as they are under a lot of stress and I think, many struggle to get the
levers/cables/hydraulics set up just so ad don't want to break owt. Mine, for example, only requires the top half of the pedal, so holding it in
place whilst cornering/braking is hard.
“Let your plans be dark and as impenetratable as night, and when you move, fall like a thunderbolt.”
Sun Tzu, The Art of War
My new blog: http://spritecave.blogspot.co.uk/
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JUD
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| posted on 21/1/07 at 08:37 PM |
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Yup, ditto that technique. Heel and toe needs to be mastered soon though!
---------------------
MK Indy Blade
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DIY Si
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| posted on 21/1/07 at 08:42 PM |
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Other way of looking at it is that you can pretty much use 2nd and 3rd on most roads and not need to up or down shift much. 
“Let your plans be dark and as impenetratable as night, and when you move, fall like a thunderbolt.”
Sun Tzu, The Art of War
My new blog: http://spritecave.blogspot.co.uk/
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SixedUp
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| posted on 21/1/07 at 11:14 PM |
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I can see I'm going to have to get me a BEC one day, just to see what its like. Unfortunately I've already promised myself a big V8 (with
ludicrous fuel consumption) first, before the government outlaws them!
So many lovely machines, and so little time ...
Cheers
Richard
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DIY Si
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| posted on 21/1/07 at 11:17 PM |
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Just have both, go for the Cyclone V8! Nice V8, silly fuel, lots of mentalist noise! 
Just need £15-20 odd K!
“Let your plans be dark and as impenetratable as night, and when you move, fall like a thunderbolt.”
Sun Tzu, The Art of War
My new blog: http://spritecave.blogspot.co.uk/
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Ferrino
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| posted on 22/1/07 at 02:09 PM |
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Hi, I didn't say that I intended to use engine-braking as a means of stopping (the 4-pots do a pretty good job of that in such a light car!),
but it is an inevitable consequence of not blipping the throttle as you downshift. However, as Chris mentions, it can be minimized by shifting down
later, which is how I think do it, as I have never experienced any wheel-locking. Something I will play around with......
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cossiebri
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| posted on 22/1/07 at 09:18 PM |
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quote:
Originally posted by JoelP
Must say thats all IMHO, and i never mastered the BEC as well as i did the CEC.
BUT joel! it was the video of you on the track (and the noise) that sold me the car
If it doesn't fit MODIFY it!!
Cheers BriF
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JoelP
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| posted on 22/1/07 at 09:37 PM |
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lol, id call myself a keen amateur, but i'll be practising again soon.
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Fredrik Jönsson
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| posted on 1/2/07 at 09:27 PM |
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What about shifting up? Do you use clutch on a BEC?
Fredrik, Sweden
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Hellfire
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| posted on 1/2/07 at 09:39 PM |
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Only from 1st to 2nd if taking it nice n steady, otherwise clutchless upshifts all the way. Just need to get the revs to about 4K to make it smooth
once you're out of first.
Phil
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MOz
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| posted on 2/2/07 at 09:40 AM |
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Having ridden and raced bikes for 12 years plus now I can say with experience that locking the wheels on downshifts is alot more dangerous on a
bike......
What about slipper clutches?????? How well do they work on a BEC???? They are invaluable on a superbike especially if you track it/race it.
MOz
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G.Man
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| posted on 2/2/07 at 09:44 AM |
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Slipper clutches are good, as long as you dont mind changing clutch plates even more regular like...
I find a hand throttle is an excellent option.. Lots of people use hand clutches on gearbox karts so they can left foot brake, I prefer to use the
hand level connected to the throttle so you can blip the throttle by hand on the downshift..
then you can use your feet on the clutch and brake without any problems, and you get alot more feel than you do with heel and toe (which I am
presently using 'til i fit my hand throttle)
[Edited on 2/2/07 by G.Man]
Opinions are like backsides..
Everyone has one, nobody wants to hear it and only other peoples stink!
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Coose
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| posted on 2/2/07 at 09:48 AM |
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I never dump the clutch out on downshifts - I use it to control the rear wheels and stop them from locking up. It stems from racing Supermotos and
also classic bikes (see left!).
Saying that, I have been known to get carried away before and end up pointing in the wrong direction! 
Spin 'er off Well...
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bitsilly
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| posted on 2/2/07 at 07:48 PM |
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I must stop reading these threads, off to drown my sorrows in beer now as feeling rather inadequate.
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Coose
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| posted on 2/2/07 at 10:50 PM |
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Mmmmmmm.... Beer is good.....
Plus, the barmaid in my local was looking rather splendid tonight!
Spin 'er off Well...
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