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Foghorn
18-08-2010, 12:10 PM
Last night I read a post by Skizzi regarding gear selection (how too and where too) it got me thinking because Throttle Control and Gear Selection fit hand in glove, within our ranks there at Racers and Coaches who no doubt can add input as well. So I did some searching and found this write up below.

Most riders look at the throttle simply as the "go-fast" control: open it to go faster, close it to slow down. But in fact the throttle is much more than that. Because the engine affects the motorcycle's dynamics so much-especially in the middle of a corner-the throttle can be used as a tool to help your bike's chassis work better. When the motorcycle is under power, there are several factors that work in your favor. The chassis is more stable as the engine's spinning internals add more gyroscopic effect to the mix. There is less load on the front end, allowing the suspension and tire to work better as well as reducing the risk of a front-end crash. And opening the throttle brings the rear-end squat characteristics into play as well, improving the suspension action and tire grip at the rear end as well. If you've ever found a false neutral in a turn or experimented with coasting down a twisty hillside, you'll know how much the engine can influence the chassis. With no power applied, both the steering and suspension work differently and can cause some tense moments midcorner. (And no, we aren't recommending that you coast down a twisty road to try this)

It's important to know that the act of opening the throttle doesn't necessarily mean you will speed up. The initial application of power is usually not enough to overcome the friction and aerodynamics involved, and the motorcycle will continue to lose speed. In faster corners, data shows that the throttle needs to be as much as 20 percent open before the bike will begin to pick up speed. Expert-level riders know this and have the throttle open well before the apex of a turn, while the motorcycle is still slowing down. This is one aspect you can experiment with: On a straight stretch of deserted road, practice closing the throttle and then smoothly opening it just enough so that you are still slowing down but you can feel the slack taken out of the drivetrain.

When you are braking, you should be gripping the tank with your knees to take the weight off your arms; keep your elbows bent, and this will give you better control of the brake-to-throttle transition. Release the brake gradually as you lean into the turn and the cornering forces take over. Once you've completely released the brake lever but before you reach full lean is the time to open the throttle. You want to keep the time you are coasting with no brake or throttle applied to a minimum, and how you open the throttle initially is just as important as when. In Reg Pridmore's book "Smooth Riding the Pridmore Way" and at his CLASS riding schools, Pridmore advises leaving the index and second fingers on the brake lever and using just the third and fourth fingers to apply the throttle. This is an advanced technique, but can significantly reduce the downtime between braking and throttle application.

In a long sweeping corner, hold the throttle open just enough so that you maintain a constant speed, and avoid the temptation to grab a handful of gas if you think you are going too slow. It's better to smoothly and gradually apply the throttle for two reasons: One, you won't have to abruptly close the throttle when you end up gaining too much speed, wasting all the hard work up to that point. And two, this is the area where the chance of a highside crash is greatest. Be smooth with corrections, and avoid closing the throttle completely if possible.

The smoother you can apply the throttle at this point, the better. Ideally, you want just enough power applied to take up the slack in the drivetrain and unload some of the weight from the front wheel, while still reducing speed as you near the apex of the turn. Another benefit of having the power on at this point is that you unsettle the chassis less at the apex if your bike has notchy throttle response-the abruptness will have occurred while the bike was a bit more upright and not as affected. Smoothly roll the throttle on so that you reach your minimum speed right at the apex of the turn and can add speed from there. Note that this is easier practiced on longer, faster turns, where you have more time available and quite a bit of power is necessary to overcome the aerodynamics before acceleration can actually begin.

With the throttle already open at the apex, the slack taken out of the drivetrain and the suspension settled and ready for acceleration, you will get a much better drive out of the corner than you would otherwise. This pays dividends all the way down the next straight with more speed. With practice, you'll find that getting on the gas smoothly and early pays off in many aspects, allowing you to ride quicker on the racetrack and more safely on the street.

Wattie
18-08-2010, 12:19 PM
hmmmmmmm

i tend to just get on it nice and hard when im past the apex, and hang on for dear life.

Kris
18-08-2010, 12:24 PM
This may be common knowledge to alot of people, but it wasn't to me and was given to me by a very experienced/fast racer.

For T4 and T8 especially at the creek, turns that can be tricky due to camber etc or dips/crests and where you can come unstucky quite easily, its best to be in a higher gear with less rpm to maintain chassis stability and gently roll on, rather then being in a lower gear with alot higher rpm. It will mean you'll need to drop 1 more gear but the benefit of midrange torque and chassis stability is worth its weight. Youll be using the torque/midrange of your engine then outright grunt in the higher rpm

I now use 4th gear through T8 just to increase the bikes stability - it made a huge difference and the roll on out of T8 into T9 is smoother and more controlled.

More a point for novices, as I said, common knowledge to 99% of you but it wasnt for me :)

Dunno
18-08-2010, 12:52 PM
I once read P.F Chilli used to race with the bike idling at about 4000 rpm for the same reasons stated above. Even when he was off the throttle the bike was still propelling him forward & the engine spinning. I might have to try it one day.

HYPE
18-08-2010, 01:05 PM
i usually run the 600 idle between 2.5-3000rpm

use to run the R1 @ 2-2200rpm

oldblade
18-08-2010, 01:21 PM
I run mine at near 2k rpm cause of the big jolt forward I get when I turn the tap from off to on
This fixes that problem now I know it also helps in other areas cool

Naked Twin
18-08-2010, 01:36 PM
I found on the old zx7 that running with a higher idle around 2000 gave a good feeling at tip in, more experienced (read better) riders were up around 3000 where Hype is talking. I tried it but felt it was pushing too hard on the entry. As I said a better ride would have made better use of the additional revs. The big difference to me was it made the turn in very smooth as it was essentially applying a little bit of throttle, perfect for tip in.

Now I am just a broken down hack who can't even tip the bike in.

Nick

WET4URacing
18-08-2010, 01:40 PM
my bikes idle at the manufactures specs

Wattie
18-08-2010, 01:48 PM
i tried running a higher idle a massive 1800 revs, and didnt like it.

back to stock idle for me.

Vid's Z1
18-08-2010, 02:53 PM
Very good write up FogHorn :ayyy:

I guess we can all improve and be more smoother, as time goes.

I believe in the slow in, fast out theory, whilst in the corner no need to apply further gas as this will cause problems.
Just keep it level as per how the corner rolls..

Anyhow im a newbie, with a steep learning curve...:rolleyes:

stetto
18-08-2010, 05:20 PM
I found on the old zx7 that running with a higher idle around 2000 gave a good feeling at tip in, more experienced (read better) riders were up around 3000 where Hype is talking. I tried it but felt it was pushing too hard on the entry. As I said a better ride would have made better use of the additional revs. The big difference to me was it made the turn in very smooth as it was essentially applying a little bit of throttle, perfect for tip in.

Now I am just a broken down hack who can't even tip the bike in.

Nick

I run my 7 at 2K aswell, more for smoother pickup though not so much corner entry

Blurr
19-08-2010, 03:10 AM
yep some advice from some more experienced riders saw me up my idle to 2-2500rpm.

SKIZZI
19-08-2010, 11:51 AM
Nice find..

I don't know if it true but I read somwhere that upplying that small amount of throttle mid corner transers weight to the rear and doesn't "squat" the bike like most think but actually raises the rear and shortens the wheelbase to tighten up the turn. ( this is of course in comparrison to not opening the throttle until after the apex).

warwick
20-08-2010, 01:33 PM
This sounds a bit away from it but my Triumph 600 revs to 14000 and i try to keep it at all times above 8000 when it gets to 8ooo slip it down another gear so at no time other than starting do i want it at 2000 revs .
I dont know what turn 1 revs are 2nd gear and pulling once i have my ear in I dont look near the instruments .Only down the straight to keep changing up before the rev limiter steps in.
These bikes are built to rev their tits off but make sure you use the good oil.
All that about throttle is true and will come more to play at slower speeds on the road but on the track I dont see any use in increasing your idle revs unless you brake way early and turn the trottle off -but dont you brake and just snick back the gears so as to be in the power range while holding the revs around the 8000 mark
My motor sounds tinny when not in the power so i find it happier to be up there. Just a thought it works for me.

warwick
20-08-2010, 01:48 PM
Sorry guys I forgot myself I am in general talk where I was thinking along the lines of track work -of course you should have the idle set up for a smoothe up tempo accelerate when you apply the gas You will be surprised by how many riders have sticky cables or kinked check yours out too . you can get a cable oiler for $10 learn to clean and oil them. Also chain oil and condition and tension Make a big difference just dont increase your idle to mask other problems.
he he lol it would look funny doing kmart car park at 8000 revs forgive this old fool:mad:

Dave75
20-08-2010, 07:37 PM
Hey does anyone know what the motogp And wsb run their bike idle at?

Foghorn
20-08-2010, 07:45 PM
Wetty, Wattie & Racegodr1 etc a bound to know - is it true that the GP bikes rev out at about 22,000 rpm?

Schtevo
20-08-2010, 10:02 PM
Wetty, Wattie & Racegodr1 etc a bound to know - is it true that the GP bikes rev out at about 22,000 rpm?

When they show the telemetry on the TV the GP bikes change up at around 18,500RPM - no idea how accurate the TV telemetry display is though