Flat Shifter vs Geartronics vs ---

[Christopher Crowe]

Would folks like to give their opinions on the merits of the two systems? Weight vs performance vs cost...

I've also heard of a few new shifter units that are said to be coming to the market -- anyone know anything about these?

Thanks,

Chris

[F1000champ]

IMHO, the new Pro-Shift PS3 is the way to go.....sorry Nicholas, I know you have other ideas...LOL

[starkejt]

Flatshifter is much less sophisticated, doesn't physically actuate the shift, basically just provides a timed ignition cut when it senses you making an upshift. Some of the models have timed blip as well for the downshift.

Geartronics has a fancy sensor on the shifter drum, an air compressor, an air tank, fancy paddles with microswitches, pneumatic actuators on the shifter and throttle, trick solenoid vales, and a processing unit. Nothing is timer based, it is all based on the sensors and the other values it is reading from the engine. There are also a whole bunch of parameters that get adjusted. Once it is setup, basically every shift is a textbook shift. Because it is closed-loop, each shift may have different ignition cuts, different blips, etc based on the sensor values. There is also the infamous, much-debated over rev protection. Obviously, it's way more complex and way more expensive. Probably 4-5 times as much as Flatshifter, depending on models.

I don't think any individual has used both Proshift PS3 and Geartronics, so be wary of someone that says for sure that one is better than the other. F1000champ's series has Proshift as a sponsor, and Belling sells Geartronics, so they may not offer an objective view on one system vs. the other. I am a Geartronics owner, I think it's a great system, but Proshift might be just as good as far as I know.

Many people have had success with Flatshifters. I think it depends largely on your shifting mechanism and your technique. Flatshifter is inexpensive enough and simple enough to install that you can buy one to try, and sell it off if you don't like it without taking a bath. Geartronics is expensive and adds maybe 15 lbs. depending on installation, which is labor intensive, but it truly works as advertised.

[VehDyn]

The Proshifter in the past has had problems with the solenoid actuator due to heat issues in the engine compartment. I think the PS3 system has advertised they have solved those problems. John Berg has used it successfully in his IMSA lites West car last year.

The air based systems seem pretty robust. Geartronics has been around for a while and has them in quite a variety of cars on the other side of the pond. Its a bit heavy though with the pump, but wont need a bottle refill like the other air based systems. Its also a pretty sophisticated system.

What new systems are you referring to? Links?

[F1000champ]

Starkejt,

You are right on your assessment. Both Geartronics and Pro-Shift are good systems, as is the flat shifter.

The Formula 1000 Championship Series does have Pro-Shift as a sponsor, so yes I am probably a bit biased. But here is what I can tell you about the Pro-Shift system. The PS3 has no air tank, no pneumatics, its electronic. Therefore, less weight than the Geartronics. The install was fairly simple, as the brackets to install are made especially for each type of engine. The shifts are immediate and precise. There are numerous parameters that you can set in relation to shift timing (engine cut off, etc.), but we are still using the factory settings.

We've used it now for two events (Road Atlanta & Charlotte) and it has worked without any hiccups. We did have to realign the shifting mechanism at Charlotte, but that was our own doing, not the shifter's fault. And yes, the PS3 has resolved the heat issue that was a problem in the past.

And yes, it has the infamous (save your engine from overrev) downshift feature that enables you to not worry about going down through the gears too fast under braking. I won't say one is better than the other, as I've never worked with the others out there. All I can say is that the Pro-Shift system is fantastic.

[starkejt]

About Geartronics or other pneumatic systems, there are MUCH lighter compressor options available now. I forgot the numbers, but the original one is like 7 lbs., there are some that are maybe 2 lbs or so now.

Geartronics requires you to rely heavily on the dealer for software configuration since they will not allow users to have the full version of the software, and there is no telling what part of the world he might be in at any time, and it's rarely the East Coast. Most of the time you can email him the config off your system for tweaks and changes, but there are times when you need him at the track with you, namely the initial install. It hasn't been a problem for me, but I would prefer being able to make a lot of the changes myself.

[graz]

Flatshifter do have an electric solenoid gearshift system and paddles, also the Flatshifter expert system also has a built in downshift over rev protection system built in lawrence loshak uses the flatshifter expert system,see below.

[FONT= ][FONT=Calibri]we have won every race except one where we decided to run intermediate tires in heavy rain and finished 4th. We also have set a new track record every race weekend. Been quite a fantastic season.email email rec from lawrence on 25/08/2011[/FONT][/FONT]
[FONT= ][FONT=Calibri][SIZE=+0][SIZE=3]VIR In-car video is up on YouTube!! Check it out and it will show you [SIZE=4]how awesome your system works.[/SIZE] [/SIZE][/SIZE][/FONT][/FONT]
[FONT= ][FONT=Calibri][SIZE=+0][SIZE=3]It worked great at VIR! We won both races and we set a new track record by 1.1 seconds! [FONT=Arial Black](Expert system)[/FONT][/SIZE][/SIZE][/FONT][/FONT]
[FONT= ][FONT=Calibri][SIZE=3]Feel free to use it or any of my videos for your promotion.[/SIZE][/FONT][/FONT]
[FONT= ][SIZE=3][/SIZE][/FONT]
[FONT= ][FONT=Calibri][SIZE=3]http://www.youtube.com/watch?v=MfoQ01ZoxcY&feature=channel_video_title[/SIZE][/FONT][/FONT]
[FONT= ][SIZE=3][/SIZE][/FONT]
[FONT= ][SIZE=3][/SIZE][/FONT]
[FONT= ][FONT=Calibri][SIZE=3]Thank you,[/SIZE][/FONT][/FONT]
[FONT= ][SIZE=3][/SIZE][/FONT]
[FONT= ][FONT=Berlin Sans FB][SIZE=3]Lawrence loshak[/SIZE][/FONT][/FONT]
[FONT= ][FONT=Berlin Sans FB][SIZE=3]Vice President of Manufacturing[/SIZE][/FONT][/FONT]
[FONT=Tahoma][SIZE=+0]'10 DSR National Champion USA[/SIZE][/FONT]
[FONT=Tahoma][SIZE=+0]'09,'10 Cendiv DSR Champion
'05,'07 Cendiv EP Champion
'06 EP National Champion USA[/SIZE][/FONT]
[FONT=Tahoma][SIZE=3][/SIZE][/FONT][FONT=Tahoma][/FONT]

h[FONT=Times New Roman][SIZE=+0]ttp://www.youtube.com/watch?v=lpJ-Y-9otO8[/SIZE][/FONT][SIZE=3]Lee Adams GWR Raptor at Doune hill climb with new class record (Blip system)[/SIZE]
[SIZE=3](3rd in British championship at time of writing)[/SIZE]
[SIZE=3][/SIZE][FONT=Arial][SIZE=3][/SIZE][/FONT]
[SIZE=3][/SIZE][FONT=Calibri][SIZE=4][SIZE=+0]http://www.youtube.com/watch?v=MdYDvNP0md8[/SIZE][FONT=Arial][SIZE=3] Megabusa Sweden [SIZE=3](Expert[/SIZE][SIZE=3] system)[/SIZE][/SIZE][/FONT][/SIZE][/FONT]
[SIZE=3][/SIZE]
[SIZE=3][/SIZE]
http://www.youtube.com/watch?v=FAEJbHqA7-M[SIZE=+0] [SIZE=3]And here's another video where we broke the lap record and 1st place [/SIZE][SIZE=3]. [/SIZE][/SIZE]
[SIZE=3]at a sprint event the same year both using flatshifter (Expert system)[/SIZE]
[SIZE=3]regards[/SIZE]
[SIZE=3] graz[/SIZE]

[RobLav]

I am announcing the introduction of my TorqueShifter (TM) shift system. Made up of bent 4130 steel rods and a torque crossover tube made with genuine Taiwan-cheap roller bearings housed in 7075 aluminum pillow blocks, this system has proven itself on multiple track events to be reliable, accurate, and quick. You can shift down four gears just as fast as your brakes allow. A premier advantage of my system is that when you jam the shift lever backwards looking for that 7th gear, the stresses are taken up by the bent rods and torque tube. One system is already sold, and I can make up new ones for the grand price of $150.00. This system is far more effective than a cable and is orders of magnitude less expensive than automatic systems.

[starkejt]

Your ideas are intriguing to me, and I would like to subscribe to your newsletter.

[ASRF1000]

There you go, another shift system.....but, beware....it could get outlawed.....LOL

In the spirit of this forum, don't you think you'd be better off if you offered a discount on your $150 system to ApexSpeed members?

[R. Pare]

Peanut gallery discount puts it at $275 each.

[VehDyn]

Not whizzy enough. How much for a carbon fiber version.

[RobLav]

Carbon is not elastic enough. Subscriptions to my Newsletter can be had for $20 per month. Otherwise subscribe to my blog called "The Use of Cost/Benefit Analysis in Racing" and then tolerate all the popups.

I guess my main point to all this facetiousness is that at some point, the marginal cost of certain items in racing far outweighs the marginal benefit given a reasonable man's budget. My second point is to just get the cars on the track and stop worrying about all these little things. There is far more variance within the nut behind the wheel than there is in any shifter system.

[VehDyn]

The by all means, just wrap it with a carbon sticker. Same effect.

[starkejt]

The by all means, just wrap it with a carbon sticker. Same effect.

Not true, the carbon sticker is also +5hp.

[DonArm]

Another system. Looks interesting

http://www.shiftec.com/

[Nicholas Belling]

At Geartronics, we believe that pneumatic (compressed air) actuation is
superior to actuation using 12v electric solenoids.

Of course, don’t just take our word for it, do some research on the ‘net and
ask your fellow competitors what their experiences have been of the various
systems that are available, both air and electric. If you’ve taken the time to
read this document, you will at least be in a better position to ask some
important questions before handing over your hard-earned cash.

Here are ten FACTS to get you started…

1. A gearshift takes a variable length of time to complete. This remains true
regardless of vehicle type or the method of actuation, be it manual, solenoid,
hydraulic or pneumatic. The shift time is influenced more by engine
characteristics and track conditions than by gearbox type or method of
actuation. When asked how long the Geartronics system takes to change
gear, we simply reply “as long as it takes!”

Always remember the above, it is crucially important!

2. Different gearboxes require differing forces to operate them. As a general
rule, motorcycle gearboxes require less force to operate than car gearboxes.
Once manufactured, the force produced by a 12v electric solenoid cannot
easily be altered without sophisticated power control techniques. Adjusting the
operating force of a pneumatic actuator is as simple as altering the operating
air pressure.

3. Pneumatic (compressed air) systems are NOT unreliable. This is one
reason why pneumatic systems are used in industrial applications that operate
24 hours a day, 7 days a week. The duty cycle of a semi-auto shift system is
considerably less than an industrial application and reliability is not an issue.
Claims of unreliability are regularly made by some of our competitors without
them citing any examples, and they expect you to believe them.

4. A 12v air compressor does not sap any measurable power from the engine
as some of our competitors incorrectly claim. The Geartronics compressor
draws approximately 13 Amps (at typically 20% duty cycle) from the vehicle
electrical system. This equates to approximately 180 watts, in other words,
less than one quarter of one horsepower! This is clearly insignificant and it’s
wholly misleading to claim otherwise.

5. 12v electric solenoids consist of a coil of copper wire wound around a
moving armature, usually made of iron. To produce greater force from a 12v
solenoid requires that it is made bigger, and consequently heavier.

6. Despite many years of top-level gearshift development in professional
motorsport, we know of only one solenoid based shift system used by an
entire grid in a global race series. This being the highly respected Zytek
Motorsport system (as used in A1GP, Formula Nippon & LMP sportscars etc.)
Ask yourself why. The Zytek ‘EGS’ system does not use 12v solenoids, but
instead uses high voltage high efficiency solenoids and a highly sophisticated
gearbox control unit (GCU) that doubles as an energy storage unit.

7. At least one manufacturer claims that their system has protection strategies
to prevent gearbox damage and engine over-revs. The fact is that it’s
impossible to have such a protection strategy if the gearbox control unit
(GCU) does not measure the gear position or the engine speed.

8. There is far more to reliable downshifting than simply blipping the throttle
and pushing the shift lever! For example, what happens if a driver requests a
part-throttle or full-throttle downshift? Some solenoid systems that offer a
downshift ‘auto-blipper’ use a simple diaphragm device that is powered by
engine vacuum. On the face of it, this seems like a good idea, but remember
that a race engine will usually have separate throttle bodies for each cylinder,
and the available vacuum will be virtually zero because of the need to keep
the throttles open to maintain the engine idle. Also, at low engine speed, the
engine vacuum will be even less.

9. Paddleshift is faster than manual shift, but not by much. We have read one
claim that a solenoid shift system resulted in a saving of “over 1/5 of a second
per shift”. First of all, any decent driver using a manual stick will be easily
capable of performing a shift in less than 1/5 of a second (200ms) to start
with. In our experience, a typical semi-auto upshift will take between 40 and
100ms to complete (see point 1). Even if this represented a saving of 50ms
over a manual shift (which is pretty optimistic), this doesn’t correspond to a
reduction in lap time of 50ms. The only reduction in lap time comes from the
extra 50ms of acceleration during each shift, so during a typical lap consisting
of perhaps 10 upshifts, the vehicle will be accelerating for 1/2 second longer
than the same vehicle with manual shift. Unless you have an extremely high
performance car (e.g. F1) the ‘straight line’ gains are unlikely to be big enough
to measure.

10. Pneumatic actuators provide high levels of compliance with the gearbox
shift mechanism – think of the cushioning effect of the airbags in a car.

So, back to point 1. This is the big one! Regardless of the method of
actuation, every gearshift (up and down) takes a varying length of time to
execute. We can show you high-resolution data logging to demonstrate this if
you remain unconvinced. Lets first look at upshifts, mainly because they are
easier to understand than downshifts.

When we initiate the shift, we operate the actuator and cut the engine power
to remove the torque from the gearbox to allow the dogs to disengage. At first,
nothing happens, and the barrel and selector fork don’t move beyond their
‘free play’. This is because of a phenomenon known as ‘transmission windup’,
and is caused by the minute twisting of the shafts in the transmission and
the flexing of the tyre sidewalls. This wind-up effectively stores energy in the
transmission and prevents the dogs from disengaging until the energy has
dissipated. It’s not too difficult to understand that the degree of wind-up
changes with varying conditions. Factors such as engine torque, gear ratios,
track grip, wheel-slip etc. all factor into the equation, and it becomes
impossible to predict the time it will take for the energy to dissipate and hence
the shift to execute. What you might not appreciate is the variation between
the fastest & slowest shifts. On the same car, in the same gear, we have seen
variations in shift times of more than 200ms!

So what happens if we use a fixed duration engine cut, as is the case with
many aftermarket shift systems? Sure, you can cut the engine for long enough
so that the shift is always successful, but then what if the shift completes in
only half the cut time? We are then into the situation where the car is
mechanically in the next gear but the engine is still turned off. Remember that
the throttle is wide open at this point and under these circumstances the
engine simply becomes a compressor and works as a very effective brake.
The momentum of the car is then driving the engine, and the gearbox is
transmitting negative torque, which suddenly slows the car. This can lead to
loss of grip and vehicle instability, contrary to the claims that are made on
some of our competitor’s websites. When the engine power is eventually
resumed, there is a sudden shunting of the transmission as the torque
reverses, and the shift is often very aggressive as a result. So instead of
saving time, the total shift event has actually lost track time and potentially led
to a loss of control.

You might think that the way to overcome this problem is to reduce the engine
cut time. This is definitely not the correct thing to do, and you risk serious
gearbox damage if you go too far. If the cut time is reduced too much, the
currently selected gear will never disengage because the transmission has not
been given sufficient time to un-wind. When the driver calls for a gear, he/she
will feel the engine cut, but there will be no gearshift. Frustrating, but not
usually damaging. However, there is a much more serious scenario – imagine
the situation where the engine cut is just long enough to disengage the
current gear but not sufficiently long enough to allow the next gear to engage.
Remember that the throttle is wide open at this point, and as the engine is
turned back on there is no drive to the wheels, so the engine RPM rapidly
increases to the rev-limiter (if there is one). Depending upon its design, the
gearbox may either try to drop back to the previous gear or carry on to the
intended gear. The extreme speed mismatch between the slowing dog ring
and the accelerating gear causes a failed shift and also severe gearbox
damage as the dogs rapidly skip across each other and fail to engage.

So what is the solution? The only way to ensure that a gear shift is successful,
but without cutting the engine for too long, is to monitor the position of the
gearbox selector barrel and cut the engine for exactly the right duration for
every shift. This constant monitoring of the barrel position is referred to as
“closed-loop” operation. By resuming engine power as the next gear engages,
we get the fastest and smoothest shifts possible. Closed-loop operation
eliminates any chance of dog damage because the engine is never turned
back on prematurely.

Downshifts are even more complex than upshifts and the potential for gearbox
damage is even greater. We can’t divulge specific details of our downshift
strategy because it would give the game away. Suffice to say, it’s far more
complicated than simply pushing the lever and blipping the throttle.

The importance of closed-loop operation cannot be overstressed. To
determine if a paddleshift system uses open-loop or closed-loop operation,
simply ask the vendor if their system connects to the barrel position sensor or
a linear position sensor on the gear lever. If it doesn’t, then it’s not closed-loop
and you run the risk of seriously damaging your gearbox!

One final thing to bear in mind when making the choice between the various

systems on offer is the means by which the system is set up and adjusted.
Ask the vendor if setup software is supplied with the system. You might be
surprised to learn that many systems don’t even have any setup software!
One solenoid-based system we are aware of is imprecisely adjusted by a set
of screws on the side of the box, another one by a set of 3 switches. This in
itself should give you a clue as to the sophistication of the system on offer. If
you read claims that a system will “work perfectly straight out of the box”, then
be very sceptical. The Geartronics setup software has more than 110 userdefined
parameters, and they’re not there just to keep our software engineers
busy!

As we mentioned at the beginning of this document, do some research before
handing over any cash. There is a wealth of information already in existence
on numerous web forums. Do a Google search on the system you are thinking
of buying and use words such as “problem”, “fault”, “reliability” & “unreliable” in
your search criteria – you might be surprised at what you find! When you’ve
finished researching our competitors, search the forums for Geartronics and
see what the motorsport world has to say about us…


Do not hesitate to call with any questions directly to me at 604-805-6201

[Christopher Crowe]

Does anyone know the precise "as installed" weight differential between the various systems?

And Nicholas, what exactly does the latest generation Geartonics system weigh (I've heard they've gotten lighter with development).

Thanks,

Chris

[Nicholas Belling]

[FONT=Calibri]As for weight geartronics has many customers running systems with carbon fibre bottles, and light weight aluminum airline fittings, as well as light weight wiring / heat sheathing for the harness and the weight of a total system goes down just below 4kg /8.8 lbs.[/FONT]

[FONT=Calibri]If you are looking run a compressor full time you we have a new light weight [/FONT][FONT=Calibri]compressor which adds off memory about 2kg /4.4lbs to the system - total weight then would put you into the 13.2 lbs approx. with onboard compressor and accumulator tank.[/FONT]

[ASRF1000]

At Geartronics, we believe that pneumatic (compressed air) actuation is
superior to actuation using 12v electric solenoids.

Of course, don’t just take our word for it, do some research on the ‘net and
ask your fellow competitors what their experiences have been of the various
systems that are available, both air and electric. If you’ve taken the time to
read this document, you will at least be in a better position to ask some
important questions before handing over your hard-earned cash.

Here are ten FACTS to get you started…

1. A gearshift takes a variable length of time to complete. This remains true
regardless of vehicle type or the method of actuation, be it manual, solenoid,
hydraulic or pneumatic. The shift time is influenced more by engine
characteristics and track conditions than by gearbox type or method of
actuation. When asked how long the Geartronics system takes to change
gear, we simply reply “as long as it takes!”

Always remember the above, it is crucially important!

2. Different gearboxes require differing forces to operate them. As a general
rule, motorcycle gearboxes require less force to operate than car gearboxes.
Once manufactured, the force produced by a 12v electric solenoid cannot
easily be altered without sophisticated power control techniques. Adjusting the
operating force of a pneumatic actuator is as simple as altering the operating
air pressure.

3. Pneumatic (compressed air) systems are NOT unreliable. This is one
reason why pneumatic systems are used in industrial applications that operate
24 hours a day, 7 days a week. The duty cycle of a semi-auto shift system is
considerably less than an industrial application and reliability is not an issue.
Claims of unreliability are regularly made by some of our competitors without
them citing any examples, and they expect you to believe them.

4. A 12v air compressor does not sap any measurable power from the engine
as some of our competitors incorrectly claim. The Geartronics compressor
draws approximately 13 Amps (at typically 20% duty cycle) from the vehicle
electrical system. This equates to approximately 180 watts, in other words,
less than one quarter of one horsepower! This is clearly insignificant and it’s
wholly misleading to claim otherwise.

5. 12v electric solenoids consist of a coil of copper wire wound around a
moving armature, usually made of iron. To produce greater force from a 12v
solenoid requires that it is made bigger, and consequently heavier.

6. Despite many years of top-level gearshift development in professional
motorsport, we know of only one solenoid based shift system used by an
entire grid in a global race series. This being the highly respected Zytek
Motorsport system (as used in A1GP, Formula Nippon & LMP sportscars etc.)
Ask yourself why. The Zytek ‘EGS’ system does not use 12v solenoids, but
instead uses high voltage high efficiency solenoids and a highly sophisticated
gearbox control unit (GCU) that doubles as an energy storage unit.

7. At least one manufacturer claims that their system has protection strategies
to prevent gearbox damage and engine over-revs. The fact is that it’s
impossible to have such a protection strategy if the gearbox control unit
(GCU) does not measure the gear position or the engine speed.

8. There is far more to reliable downshifting than simply blipping the throttle
and pushing the shift lever! For example, what happens if a driver requests a
part-throttle or full-throttle downshift? Some solenoid systems that offer a
downshift ‘auto-blipper’ use a simple diaphragm device that is powered by
engine vacuum. On the face of it, this seems like a good idea, but remember
that a race engine will usually have separate throttle bodies for each cylinder,
and the available vacuum will be virtually zero because of the need to keep
the throttles open to maintain the engine idle. Also, at low engine speed, the
engine vacuum will be even less.

9. Paddleshift is faster than manual shift, but not by much. We have read one
claim that a solenoid shift system resulted in a saving of “over 1/5 of a second
per shift”. First of all, any decent driver using a manual stick will be easily
capable of performing a shift in less than 1/5 of a second (200ms) to start
with. In our experience, a typical semi-auto upshift will take between 40 and
100ms to complete (see point 1). Even if this represented a saving of 50ms
over a manual shift (which is pretty optimistic), this doesn’t correspond to a
reduction in lap time of 50ms. The only reduction in lap time comes from the
extra 50ms of acceleration during each shift, so during a typical lap consisting
of perhaps 10 upshifts, the vehicle will be accelerating for 1/2 second longer
than the same vehicle with manual shift. Unless you have an extremely high
performance car (e.g. F1) the ‘straight line’ gains are unlikely to be big enough
to measure.

10. Pneumatic actuators provide high levels of compliance with the gearbox
shift mechanism – think of the cushioning effect of the airbags in a car.

So, back to point 1. This is the big one! Regardless of the method of
actuation, every gearshift (up and down) takes a varying length of time to
execute. We can show you high-resolution data logging to demonstrate this if
you remain unconvinced. Lets first look at upshifts, mainly because they are
easier to understand than downshifts.

When we initiate the shift, we operate the actuator and cut the engine power
to remove the torque from the gearbox to allow the dogs to disengage. At first,
nothing happens, and the barrel and selector fork don’t move beyond their
‘free play’. This is because of a phenomenon known as ‘transmission windup’,
and is caused by the minute twisting of the shafts in the transmission and
the flexing of the tyre sidewalls. This wind-up effectively stores energy in the
transmission and prevents the dogs from disengaging until the energy has
dissipated. It’s not too difficult to understand that the degree of wind-up
changes with varying conditions. Factors such as engine torque, gear ratios,
track grip, wheel-slip etc. all factor into the equation, and it becomes
impossible to predict the time it will take for the energy to dissipate and hence
the shift to execute. What you might not appreciate is the variation between
the fastest & slowest shifts. On the same car, in the same gear, we have seen
variations in shift times of more than 200ms!

So what happens if we use a fixed duration engine cut, as is the case with
many aftermarket shift systems? Sure, you can cut the engine for long enough
so that the shift is always successful, but then what if the shift completes in
only half the cut time? We are then into the situation where the car is
mechanically in the next gear but the engine is still turned off. Remember that
the throttle is wide open at this point and under these circumstances the
engine simply becomes a compressor and works as a very effective brake.
The momentum of the car is then driving the engine, and the gearbox is
transmitting negative torque, which suddenly slows the car. This can lead to
loss of grip and vehicle instability, contrary to the claims that are made on
some of our competitor’s websites. When the engine power is eventually
resumed, there is a sudden shunting of the transmission as the torque
reverses, and the shift is often very aggressive as a result. So instead of
saving time, the total shift event has actually lost track time and potentially led
to a loss of control.

You might think that the way to overcome this problem is to reduce the engine
cut time. This is definitely not the correct thing to do, and you risk serious
gearbox damage if you go too far. If the cut time is reduced too much, the
currently selected gear will never disengage because the transmission has not
been given sufficient time to un-wind. When the driver calls for a gear, he/she
will feel the engine cut, but there will be no gearshift. Frustrating, but not
usually damaging. However, there is a much more serious scenario – imagine
the situation where the engine cut is just long enough to disengage the
current gear but not sufficiently long enough to allow the next gear to engage.
Remember that the throttle is wide open at this point, and as the engine is
turned back on there is no drive to the wheels, so the engine RPM rapidly
increases to the rev-limiter (if there is one). Depending upon its design, the
gearbox may either try to drop back to the previous gear or carry on to the
intended gear. The extreme speed mismatch between the slowing dog ring
and the accelerating gear causes a failed shift and also severe gearbox
damage as the dogs rapidly skip across each other and fail to engage.

So what is the solution? The only way to ensure that a gear shift is successful,
but without cutting the engine for too long, is to monitor the position of the
gearbox selector barrel and cut the engine for exactly the right duration for
every shift. This constant monitoring of the barrel position is referred to as
“closed-loop” operation. By resuming engine power as the next gear engages,
we get the fastest and smoothest shifts possible. Closed-loop operation
eliminates any chance of dog damage because the engine is never turned
back on prematurely.

Downshifts are even more complex than upshifts and the potential for gearbox
damage is even greater. We can’t divulge specific details of our downshift
strategy because it would give the game away. Suffice to say, it’s far more
complicated than simply pushing the lever and blipping the throttle.

The importance of closed-loop operation cannot be overstressed. To
determine if a paddleshift system uses open-loop or closed-loop operation,
simply ask the vendor if their system connects to the barrel position sensor or
a linear position sensor on the gear lever. If it doesn’t, then it’s not closed-loop
and you run the risk of seriously damaging your gearbox!

One final thing to bear in mind when making the choice between the various

systems on offer is the means by which the system is set up and adjusted.
Ask the vendor if setup software is supplied with the system. You might be
surprised to learn that many systems don’t even have any setup software!
One solenoid-based system we are aware of is imprecisely adjusted by a set
of screws on the side of the box, another one by a set of 3 switches. This in
itself should give you a clue as to the sophistication of the system on offer. If
you read claims that a system will “work perfectly straight out of the box”, then
be very sceptical. The Geartronics setup software has more than 110 userdefined
parameters, and they’re not there just to keep our software engineers
busy!

As we mentioned at the beginning of this document, do some research before
handing over any cash. There is a wealth of information already in existence
on numerous web forums. Do a Google search on the system you are thinking
of buying and use words such as “problem”, “fault”, “reliability” & “unreliable” in
your search criteria – you might be surprised at what you find! When you’ve
finished researching our competitors, search the forums for Geartronics and
see what the motorsport world has to say about us…


Do not hesitate to call with any questions directly to me at 604-805-6201

Great sales pitch Nicholas....LOL

[mousecatcher]

At Geartronics, we believe that pneumatic (compressed air) actuation is
superior to actuation using 12v electric solenoids.

I'm sold, but ...

9. Paddleshift is faster than manual shift, but not by much. We have read one
claim that a solenoid shift system resulted in a saving of “over 1/5 of a second
per shift”. First of all, any decent driver using a manual stick will be easily
capable of performing a shift in less than 1/5 of a second (200ms) to start
with. In our experience, a typical semi-auto upshift will take between 40 and
100ms to complete (see point 1).

ok, but

Regardless of the method of
actuation, every gearshift (up and down) takes a varying length of time to
execute. We can show you high-resolution data logging to demonstrate this if
you remain unconvinced. Lets first look at upshifts, mainly because they are
easier to understand than downshifts.

When we initiate the shift, we operate the actuator and cut the engine power
...
Factors such as engine torque, gear ratios,
track grip, wheel-slip etc. all factor into the equation, and it becomes
impossible to predict the time it will take for the energy to dissipate and hence
the shift to execute. What you might not appreciate is the variation between
the fastest & slowest shifts. On the same car, in the same gear, we have seen
variations in shift times of more than 200ms!

You're claiming first that there isn't 200ms to be saved, and then go on to note how hard it is to complete an upshift (quickly, correctly) when there is inherent variability of >200ms. These statements do not seem to agree with each other.

[glenn cooper]

Talking about the Geartronic's up shifting strategy is akin to looking at a photo of Rita Hayworth in her prime and pointing out that she had 6 toes on each foot*, like a barn cat.

The down shifting abilities are where the magic is, or more specifically the multiple downshifting segments of a racecourse.

* Toe count of Ms Hayworth may or may not be accurate.

[ghickman]

Awesome analogy Glenn. I miss the Coop Cronicals

I'm in total agreement with Glenn, the downshifts are where it all happens.

I recently switched to the Geartronics; now I can downshift without feeling like I have to rehearse it in my head before doing it.

Those looking to install a Geartronics I have some nifty parts that make the installation much easier. Feel free to contact me.

[mousecatcher]

Interesting. I never considered left foot brake manual downshifting a problem. For certain corners (not too heavy on the lat g's), eg there's one at MMP, I'm even quite confident to downshift mid-corner.

But obviously the human machine is better at some stuff than electromechanical machines.

I'm adding paddle shifters to a sedan car for gearbox reliability, not performance per se. It hadn't entered my mind that downshifting would be the trick part. Thanks for that insight.

Anybody have direct experience shiftec vs geartronics?

[glenn cooper]

Mouse - you're still not "getting it" in regard to Geartronics.
Do a search and read much more indepth info.

[mousecatcher]

Mouse - you're still not "getting it" in regard to Geartronics.
Do a search and read much more indepth info.

um, pretty sure I get it. downshifting is hard. geartronics does it well. what am i missing? AFAICT shiftec is also a closed loop pneumatic shifter that has their own strategy for up and down shift which isn't just simply fire and forget.

Help me out here, what am I not getting? I've read the entire geartronics site and other info on the web.

[Phil Picard]

weve installed and service both of these systems in our shop. I must say both are fairly sophisticated and do what they're asked of. both have their advantages and disadvantages. I suppose it's one of those less filling tastes great kind of things.

[Phil Picard]

delete repeated post

[glenn cooper]

]Interesting. I never considered left foot brake manual downshifting a problem. [/B]It's not. What is a problem in our cars, with their motorcycle transmission that was never designed to down change at anywhere near the rate we can do with car brakes and tires, AND having those multiple downshifts happen 100% of the time.

For certain corners (not too heavy on the lat g's), eg there's one at MMP, I'm even quite confident to downshift mid-corner. By mention of the lateral G's, I'm going to assume you are describing down shifting an "H" style, dogring box, ie Hewland Mk9, etc, which indeed does become tricky under heavy lateral G's.
But obviously the human machine is better at some stuff than electromechanical machines.

I'm adding paddle shifters to a sedan car for gearbox reliability, not performance per se. It hadn't entered my mind that downshifting would be the trick part. Thanks for that insight.

Anybody have direct experience shiftec vs geartronics?

If I have misconstrued your post, I apologise.

GC

[crice]

weve installed and service both of these systems in our shop. I must say both are fairly sophisticated and do what they're asked of. both have their advantages and disadvantages. I suppose it's one of those less filling tastes great kind of things.

Sorry to drag up an old thread, but please could you elaborate Phil on the pros/cons of each (Geartronics vs Shiftec) as I'm currently considering both (using either company's GCU too to feed into an SQ6). Many thanks.