eccsmk
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 posted on 3/5/09 at 09:29 PM |
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videos of gear changes
has anybody got a video of them changing gear without the clutch and without the aid of a trickshifter??
ive been having another practice today (mainly downshifts) and my heel and toe down shifting leaves a little to be desired!!
thank you
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Moorron
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| posted on 3/5/09 at 09:50 PM |
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are you using the clutch or not? Heal and toe is using the clutch?
Anyway, i found the ZX12R easier to do clutchless changes than my old CBR engine. On up shifts just back off the throttle a little and force it into
gear should be easy. On down shifts i leave the clutch alone and just brake with one foot and blip the throttle with the other and it goes straight in
gear. Only 1-2 and 2-1 are the ones that are hardest, all others are smooth.
Dont know how long the gears will last tho lol
I only use the clutch when cruising and downshifting and also pulling away hehe
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eccsmk
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| posted on 3/5/09 at 09:56 PM |
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i can upshift ok
i do use the clutch coming down after missing the gears far too much
infact i snapped a gear nob and have broken my lever mount (wasnt the strongest) but i think it was mainly me panicing about trying to change gear
without the clutch its all still very new to me
i suppose getting someone to show me would be better.
how are you getting on with the zx12??
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A1
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| posted on 3/5/09 at 10:15 PM |
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erm...forgive me if im wrong...but i was under the impression that clutchless downshifts were a no-no...?
cant see how it would work cause everythings under load when slowing...
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Moorron
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| posted on 3/5/09 at 10:20 PM |
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Yeh its just timing and knowing how much to blip the throttle. Once youve done it a few times you will wonder how you got it wrong.
ZX12 is great, went to stoneliegh today in it with her sitting next to me (so had to drive slowly  ) managed 30 mpg but so boring on the motorway
for an hour each way.
I have to get a new bonnet after the last one flew off and also get it rollin roaded to tweak my attempt at the fueling but im happy with the cost and
effort to upgrade.
Sorry about my spelling, im an engineer and only work in numbers.
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eccsmk
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| posted on 3/5/09 at 10:42 PM |
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30 mpg
i think a rolling road session is in order then
ive not been far but ive worked it out to 20 mpg so far
thats on zero map tho
looks like i need to spend more time in the driving seat
thank you for the advice
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eccsmk
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| posted on 3/5/09 at 10:45 PM |
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quote:
Originally posted by A1
erm...forgive me if im wrong...but i was under the impression that clutchless downshifts were a no-no...?
cant see how it would work cause everythings under load when slowing...
maybe your right
i guess the powers that be will appear and give us a theoretical slap on the wrist if we are wrong about this
thanking you
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nitram38
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| posted on 4/5/09 at 03:31 AM |
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I know that trickshifters aren't cheap, but neither is an engine/gearbox.
I can heal and toe, but a trickshifter is easy and can also help if you get the timing wrong.
Long term I think that it is a good investment.........
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ReMan
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| posted on 4/5/09 at 06:38 AM |
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Sorry I don't see what is so wrong with giving the cluth a dab on the downshifts?
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oldtimer
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| posted on 4/5/09 at 07:21 AM |
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An aunt of mine was a disabled driver with a Triumph. This was fitted with a hand operated paddle accelerator fitted behind the wheel - perfect for
blipping the throttle on downshifts, and super simple.
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Dangle_kt
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| posted on 4/5/09 at 08:01 AM |
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if you cock up a down shift with no clutch on a bike, then the rear locks up for a second - a bit squirly but not to bad for the bike.
You do the same in a car with two massive tyres (compared to bike tyre contact patch) and it weighing in at over half a ton wet with driver and your
asking for knackered selectors or gears IMO.
Its hard enough on a bike with your hands, why risk it with your feet?
Up changes seem to work fine, but down the box I'd not feel like I was having much mechanical sympothy!
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zilspeed
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| posted on 4/5/09 at 08:09 AM |
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The guide to gear changing by William Hewland.
That'll be William Hewland of HEWLAND transmissions.
So, he'll know a thing or two about shifting gears.
-------------------------------------------------
Methods of Changing Gear By William Hewland.
July 2000
The following is some info regarding shifting gear and face dog wear. I am in the fortunate position where I have a good amount of knowledge on the
subject, as I understand the mechanical side and the user (driver) side equally well.
N.B. For succesful gear shifting, remember that it is critical to ensure that all mechanical elements between the drivers hand and the dog faces are
in good order and properly set. This includes the gear linkage in the chassis!
Successful up-shifting, (defined as fast and non dog-damaging) will be achieved by fully moving the dog ring as rapidly as possible from one gear to
the next, preferably with the engine's driving load removed until the shift is completed. (The opposite is true of a synchromesh gearbox as used
in passenger cars, where slow movement helps). It should be remembered that it is not possible to damage the dogs when fully engaged (in gear). The
damage can only take place when initiating contact during a shift, (the `danger zone`) therefore this element must be made as short as possible. If a
driver moves the gear lever slowly, or if the linkage is not rigid and effective, dog wear will occur. We always recommend lightweight yet solid rod
linkage, not cables ideally.
I list below the different methods of up-shifting that are used in racing most commonly. The best at the top, the worst at the bottom:
Automated (semi automated). The movement of the dog ring is powered and the engine is cut / re-instated in a co-ordinated manner. Gear-shifts take
milliseconds. This system produces zero dog wear when set up well. It is not applicable to most cars, but it illustrates that speed of shift is a good
thing.
Manual with engine cut. This system is almost as good as an automated one as long as the driver pulls the lever very quickly. Again it is not
applicable to many cars, but it illustrates that speed of shift is a good thing. A `cheat` version of this is to shift on the engine rev limiter,
which can work well. With this system it is especially important to move the lever ultra fast, otherwise the engine will be reinstated during partial
dog engagement, causing damage. The damage can usually be felt by the driver.
Manual.
Best method: With no assistance from the engine management, the driver must lift off the throttle sufficiently to allow the dog ring to be pulled out
of engagement. He should then stay off the throttle long enough to allow the dog ring to engage with the next gear. In practice, the driver can move
the gear lever faster than he can move his foot off and back on to the throttle. Therefore the effective method is to apply load to the gear lever
with your hand and then lift the throttle foot off and back on to the pedal as fast as physically possible. In lifting your foot, the loaded gear
lever will almost involuntarily flick to the next gear before the foot is re-applied to the throttle.
Another method is to load the gear lever with your hand, stay flat on the throttle and dab the clutch to release the dog ring. The overall effect on
the gear shift is similar to the above method, but clutch wear may become a big issue.
The worst method (most destructive and definitely slowest) is to attempt to change gear in a `passenger car / synchromesh` way, i.e. lifting off the
throttle, dipping the clutch, moving the gear lever, letting the clutch up and re-instating the throttle. The method causes unnecessary clutch wear,
does absolutely nothing to help come out of gear and usually causes dog wear whilst engaging the next gear. This wear is due to several reasons.
Firstly, it is impossible for a driver to co-ordinate the complicated sequence of all five physical movements accurately. Consequently the engagement
dogs often find themselves engaging whilst the throttle is applied. The lever is usually pulled more slowly as it was not pre-loaded, lengthening the
`danger zone`.
Successful down-shifting, has similar rules applied regarding speed of shift. Unloading the dogs is done in the opposite manner obviously. Whilst
braking, the dogs must be unloaded by either touching the throttle pedal or- my preferred method- by dipping the clutch. However, one sharp dab of
clutch or throttle is appropriate per shift. Continued pressure on either will cause dog damage for different reasons. `Blipping the throttle` just
before engagement is advisable if the rev drops between gears are over 1300 rpm, as this will aid engagement and stabilise the car.
TOP TIP for ease of downshifting: Make the downshifts as late as possible in your braking zone (i.e. at lower road speed), because the rev drops
between each gear are then lower. So many drivers make the mistake of downshifting as soon as they begin braking, causing gearbox wear, engine damage
and `disruption` to the driving wheels.
This is a subject which can be much expanded on, but I feel that these are the basics, which I hope are of use.
[Edited on 4/5/09 by zilspeed]
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ReMan
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| posted on 4/5/09 at 08:48 AM |
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I rest my case
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nitram38
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| posted on 4/5/09 at 09:01 AM |
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Is Hewland talking about his own gearboxes?
His racing boxes are mostly straight cut gears and won't even go in if you don't have the revs right, plus they are very fast short
changes compared to syncromesh boxes.
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gingerprince
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| posted on 4/5/09 at 09:17 AM |
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This video has some pedal box footage (little bit at 1:30 then from 3:15ish): -
clicky linky
From before I got fitted electronic paddles. Still didn't fit a downshift blipper, just flat upshifter - I want to improve my heel and toe.
Don't bother trying to downshift without clutch, not worth it. Just practice your heel and toe. The hardest thing is reprogramming your brain
to only have part of your foot on the brake when barrelling into a corner! It's a great feeling when it works though
[Edited on 4/5/09 by gingerprince]
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eccsmk
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| posted on 4/5/09 at 10:22 AM |
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thank you for the help folks some good info as usual
gingerprince
thats brilliant!! just what i was after
im now going outside for another practice
why dont more people video their feet while driving?? 3 pages of reading explained in 3 seconds of video
**edit**
ive got to repair my gear lever before any practicing can commence
[Edited on 4/5/09 by eccsmk]
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nstrug
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| posted on 4/5/09 at 12:27 PM |
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I'm pretty chuffed that Hewland's description of how to shift a manual dog 'box is exactly what I do: no clutch on the upshifts,
heel-and-toe+clutch dip on the down shifts. Certainly on idl1975's Indyblade it works really well, and I hope that the R1 'box in the Dax
will be equally responsive.
Nick
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Mellow Matt
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| posted on 4/5/09 at 04:53 PM |
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That's an interesting read, think I'll be doing more clutchless shifts now!
Gingerprince - that's a great video, can I ask what happened a couple of times when going down that straight? Was it a false neutral or
accidentally going down a gear instead of up or something else? I ask as I'm hoping to take my locoblade on track soon, so any advice on driving
a BEC on track is handy
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gingerprince
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| posted on 5/5/09 at 07:43 AM |
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quote:
Originally posted by Mellow Matt
Gingerprince - that's a great video, can I ask what happened a couple of times when going down that straight? Was it a false neutral or
accidentally going down a gear instead of up or something else? I ask as I'm hoping to take my locoblade on track soon, so any advice on driving
a BEC on track is handy
At the time my car was missing 4th from time to time. Worn dog grooves caused I think by sloppy gear linkage.
See here for pics of what had worn.
Just make sure play in your gear linkage is minimal, otherwise you don't get a positive gear change and your cogs look like mine!
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motorcycle_mayhem
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| posted on 5/5/09 at 11:46 AM |
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Yes, I have, here's 3 laps of St. Eval with both up- and downshifts without a clutch, it was destroyed on the startline.
http://www.youtube.com/watch?v=BcLo8NhJdEA
Here's the usual upshift only, just release the throttle a little and slot the next gear in..
http://www.youtube.com/watch?v=h4-p58KlDYY
Here's my solenoid system in use:
http://www.youtube.com/watch?v=_e2tIaFbFhE
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eccsmk
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| posted on 5/5/09 at 01:30 PM |
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fantastic stuff thank you
the last video
1) looks like its a bit bumpy
2) seems strange you not moving you hand to change gear (just googling solenoid system)
quote:
Originally posted by motorcycle_mayhem
Yes, I have, here's 3 laps of St. Eval with both up- and downshifts without a clutch, it was destroyed on the startline.
http://www.youtube.com/watch?v=BcLo8NhJdEA
Here's the usual upshift only, just release the throttle a little and slot the next gear in..
http://www.youtube.com/watch?v=h4-p58KlDYY
Here's my solenoid system in use:
http://www.youtube.com/watch?v=_e2tIaFbFhE
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wheezy
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| posted on 5/5/09 at 01:51 PM |
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Here is another video to look at of some footwork on a radical SR3. The website has some other footage of heel toe techneque.
Link
Dave
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eccsmk
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| posted on 5/5/09 at 04:36 PM |
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looks my two left feet need some practice
changing up is now a doddle
changing down using heel and tow i still dont take my foot(heel) of the accelerator quick enough
practice
practice
practice (as soon as i can get to my car again)
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Mellow Matt
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| posted on 5/5/09 at 05:51 PM |
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quote:
Originally posted by gingerprince
At the time my car was missing 4th from time to time. Worn dog grooves caused I think by sloppy gear linkage.
See here for pics of what had worn.
Just make sure play in your gear linkage is minimal, otherwise you don't get a positive gear change and your cogs look like mine!
Thanks for that, that's really interesting! I'm actually going to attempt exactly what you did with your gearbox on my GSXR as the dogs
are worn (at least I suspect they are!), so those pics were quite helpful
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