G-Tech/Pro

[OB_Dirty Pete]

Anybody got a G-Tech/Pro? You see them advertised on SpeedVision all the time.

www.gtechpro.com

They're $139 accelerometers that tell you 0-60 times & speeds, 60-0 times and distances, 1/4 mile ets and speeds, rear wheel horsepower (you input vehicle weight to get hp) plus longitudinal and lateral Gs either instant or continuous.

My dyno tuner, who is well respected, uses one all the time on his own bikes. I went and inspected one today and it seemed very well built.

I'm on the verge of popping for one of these as it seems like a real-world instant dyno test, and a great way to practise your dragging technique.

Would probably be very helpful for self tuning with the PC2.

Who has some experience with them?

[This message has been edited by Dirty Pete (edited 10 April 2000).]

 

[OB_godzuki 31]

I used mine for almost two years .Its very accurate if you have smooth level and straight ground.Never tried it on a bike though.It will measure G-S IN a turn also.Instructions are very clear,take em with for referance.How was the one you saw wired up???

 

[OB_JohnC]

Had mine about a year. Same as godzuki, never used on the bike. Some of the Vette guys have used it at the track, and claim it's very accurate. I get consistant 0-60's in the cage, as well as 60-0 feet. It did show the couple of tenths I picked up changing air-boxes. As long as you keep the front tire down, it should be accurate on a bike.

 

[OB_Bob]

Yes
It works on a bike.
Dynos be gone
Bob

 

[OB_Dirty Pete]

Doesn't matter if the front wheel goes up. It just has to be level at the moment you stage so as to activate the silicone accelerometer. It rotates on a good hinge so it's easy to level when you stage no matter the attitude of your bike. It tells when it's level by displaying "-GO-"

It didn't see it mounted on a bike; just inspected it on display at a cage speed shop. It's a suction cup mount, but a good one. You could mount it on your speedo dial face, or make up a custom solid mount. I'd do the latter.

It has a conventional 12 volt accessory plug...you guys are all wired for that with your radar detectors/jammers, etc., right?

I've asked Chuck of Cyclestuff to see if he can do better than the factory-direct $139 price.

One nice thing that the site doesn't tell you: You don't have to read your results as you run. It stores them and displays the maximum values for your runs so you read them after you shut down.

 

[OB_vortech347]

A lot of the Mustang guys have run them and they say that the Gtech is very consistent but is usually about .2 quicker on the et than the clocks at the strip. I think it would be a good tool to measure performance gains. Especially if used in say 4th gear where you could baseline the bike, make a change and then check to see if the change made a difference in performance.

 

[OB_Kaw9R]

I also have a G Tech, I've never used on a bike. You won't be able to baseline in 4th, because the unit requires you to start from zero. Also, the HP value will only be as accurate as the user inputted weight of bike + rider + gas, etc.

What is the wet weight of a '00?

 

[OB_godzuki 31]

Are there any extra leads to draw power from?This shouldnt be too hard to wire up.Igot lots of time.Will someone please make it stop snowing!!!!!!!!!

 

[OB_Dirty Pete]

Kaw9, 4th gear rollons are more than possible. The unit doesn't require that you start from zero velocity. It requires that you start from zero linear Gs. So coasting on neutral throttle at the botton of 4th, setting the unit to "-GO-" then dropping the hammer and holding it to the top of 4th will give you the maximum G value obtained. The only challenge on bike will be manipulating the button with a gloved finger. I figure you'll have to perform tests with a bare right hand.

Anyway, I'm going for one.

 

[OB_JohnC]

>>
Doesn't matter if the front wheel goes up.
>>

I think it does. It doesn't swivel. If you hold it in your hands, get the "GO", and press start, you can fake a 1/4 run by just tilting it. That same tilt(front-end lifted), will give you an exaggerated acceleration time.

>>>
It's a suction cup mount, but a good one.
>>>
It looks quality, but it's not so good. Mine was porous. I couldn't see the flaws, but it fell off, in the middle of runs. G-Tech replaced it with just a phone call, claimed they had a bad batch. I haven't tried the new cup yet.

 

[OB_GSXRTURBO1]

I have one, but haven't used it on the bike. DP, coasting in 4th would be negative G's, the unit actively displays G's and you can see how minor inputs greatly affect G's. The unit is VERY sensitive, any fraction of + or - G's will not allow the unit to read. The only problem I see with a bike would be leaning from side to side. For accurate results you would have to go completely straight and not lean either way. It's worth the $140

 

[OB_Dirty Pete]

JohnC and Turbo1, thanks for the real world info.

I'm just going by what my dealer said.

I'll also ask these questions of my dyno tuner who uses the G-Tech/Pro.

John: It makes sense that tilting the unit by wheelying would add gravitational G load to the forward G load and give you a false reading. However, as long as the maximum forward G load of your run takes place with your front wheel on the ground, you'll get a valid reading.

Turbo1: I was imprecise (which you can't get away with on this board!) By "coasting," I meant neutral throttle, not trailing throttle. That would give you zero forward or backward Gs. But I'm sure you're right that no rider could pin a perfect 0 Gs long enough to reset such a sensitive instrument.

Also, I understand that tilting the unit sideways will not affect it's readings. The accelerometer only works in the unit's longitudinal axis. For example, to measure lateral Gs (cornering power) in a cage, you mount the unit sideways to the vehicle's direction of travel.

QUESTION: Can you work this unit with a gloved hand?



[This message has been edited by Dirty Pete (edited 11 April 2000).]

 

[Guest]

I've used one in my Stealth for a couple of years. I ended up installing in-dash since I only use it for 1/4 mile and 0-60. It's a little optimistic compared to track times but it's very close and consistant. It's good for checking out changes made by mods on the street. I have heard that it has problems on bikes due to the front end coming up so much producing inaccurate results but I don't know this for a fact. It's a very small unit and the buttons are VERY small. Good luck with the gloves. The good thing is once setup and ready to record you only have to push one of the buttons in to start your 1/4 0-60 run.

[This message has been edited by Todd (edited 11 April 2000).]

 

[OB_Kaw9R]

It has one switch that has 3 functions left-right + push in to start. You probably won't have problems with gloves.

Here's their website: www.gtechpro.com

There's a ? regarding motorcycles in the FAQ.

 

[DaveO]

DP,

Here's the info.....

We tried the Gtech on a couple of bikes. They were both "street" bikes that we race. Slammed, stretched R's with big motors, run LOW 9's. The Gtech did NOT work on them from standing starts. It was reading 14 sec 1/4's on these bikes. We were trying to do some testing without renting the track, at the $140 price, it would have been great if it worked.

I believe the problem was the front end "lift" during acceleration. The Gtech measures "G's" in a single plane only, it must remain 90 degrees to plane of motion(forward). If this is not the cause, then the accelerometer/software could not handle the "G's" of these bikes launch. It worked fine in our tow vehicle, but we returned it and got our $$$$ back.

If someone can get it to work on these bikes, I'm all ears....

Dave

[This message has been edited by DaveO (edited 11 April 2000).]

 

[OB_GSXRTURBO1]

DP, I wasn't aware that tilting would not affect the G-Tech, thanks for the info. Regarding your question about the gloves, I think it would be difficult to manipulate the buttons (they ARE small), but it could be done. You can take your glove off to push the buttons to get the unit ready, then put the glove back on. The unit will stay "ready" until it senses movement. The 4th gear thing could also be done, but would be difficult. The only problem I see is that the G-Tech takes aerodynamic drag into account, so when you are really at speed in 4th the unit thinks you're stopped. Not sure if that would be a problem or not. I would think you could measure HP by going from a standing start in 1st, but not applying full throttle until 3rd or 4th gear. It may not be accurate, but it would be good for measuring improvements when changing things. Anyone that uses this on a bike please fill us in on your experiences.

 

[OB_Dirty Pete]

Yeah Dave, the site says the unit freaks if you give it more than 1.3 Gs, which your bikes undoubtedly do.

 

[OB_GSXRTURBO1]

(the tilting meaning side to side, not the front wheel coming up)

 

[OB_Dirty Pete]

Just got off the blower with Jeff Bloor, my dyno guy who recently came on the board to talk about his ZX12R dyno results.

He doesn't use the G-Tech/Pro for 0-60 or 1/4 info. He just uses it to tell him rear wheel horsepower in 4th gear roll-ons.

He says it's easy, sensitive and accurate. The results, he says, are VERY close to his dyno.

You preset the unit for weight, then when you're ready to lay on the throttle you just move the switch and hit the throttle.

He uses it to test changes as subtle as airbox mods.

Good enough for me.

 

[OB_Dirty Pete]

Yes, I understood you to mean that, Turbo1. Side to side acceleration does not activate the accelerometer. Only acceleration along the longitudinal axis does that.