KZScott
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posted December 13, 2008 05:36 AM
 Edited By: KZScott on 13 Dec 2008 13:50
logging clutch slip via speed sensor and rpm?
is it possible? I allready log rpm. does the speed sensor put out a 0-5v signal? It doesnt really say in the manual. if i put rpm and input from the speed sensor together on a graph I could REALLY see what the lock up is doing and not just guess what it felt like. going by rpm and time slips does work with the DRs help, but this would be the ultimate setup. when the clutch was locked in the lines would be on the same path, but when the clutch was slipping you could see where and how much by how different the lines are on the graph. it would be really easy to see if you have enough static spring pressure off the line, where the arms are kicking in, if its kicking in too hard ect ect
I remember being told i need a digital to analog (or vice versa) converter to log rear wheel speed, which Im pretty sure used the same sensor and possibly the gear pos sensor? I could care less about wheel speed at the moment (i may later on to see about tire slip) just need to get clutch slip now 
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01 ZX-12R 8.84 @ 156.3 no bars, DOT tires. Pump Gas, NA.... turbo 8.47 @ 164.
00 ZX-12R 8.62 @ 165.2 no bars, slicks, Pump Gas, 55 shot.... turbo 8.32 @173
00 ZX-12R Fastest NA Kawasaki in the world 1: 222.046 1.5: 226.390 Loring AFB
00 ZX-12R street turbo 1: 227.9 1.5: 234.1 Loring AFB
00 ZX-12R LSR turbo 1: 263.1 1.5: 266.5 Loring AFB Worlds fastest ZX-12R
CMG Racing RCC Turbos
  
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Stuart Racing
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posted December 13, 2008 08:19 AM
Scott, That would be VERY helpful with one the lockup clutch setups that we have....To actually see where it`s slipping....Keep up up on this please.....as much as possible without giving out any secrets,lol....
Paul....
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flite leader
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posted December 13, 2008 09:08 AM
ok both of you
you always have to have a baseline
engine RPM is not you baseline & yes everyone knows you can datalog rpm
clutch slip after 1st gear should be nil..............maybe a single digit percentage
changing up to second
if you donr know rear wheel rpm [which can be equated to speed.....simple calculation]
how can you know your percentage slip.... ? ? ? ? ? ? ??
the comparison would be engine rpm......clutch rpm & wheel rpm
how could you not consider wheel rpm ? ? ? ? ? ? ? ?? ?
if you wheel & your clutch were slipping.........how would you know which
if you werent keepin track of both
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Shane661
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posted December 13, 2008 09:18 AM
Edited By: Shane661 on 13 Dec 2008 17:18
If the wheel spins, rpm and the wheel speed will increase in tandem. If just the clutch slips, wheel acceleration will remain relaitvely constant while rpm spikes up.
Shane
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flite leader
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posted December 13, 2008 09:24 AM
Edited By: flite leader on 13 Dec 2008 17:26
quote:
If the wheel spins, rpm and the wheel speed will increase in tandem. If just the clutch slips, wheel acceleration will remain relaitvely constant while rpm spikes up.
Shane
true but if you aint keepin up with wheel rpm
how do you know that ??? ? ? ? ? ? ? ? ???
no less what most riders dont know is that these bikes exhibit
wheelspin at speed over say 120mph
at bonneville it can be double digit % wheel spin...... at maxton not as much yet significant
if they didnt you could tack on a few more MPH ! ! ! ! ! ! ! top end
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Shane661
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posted December 13, 2008 09:33 AM
Edited By: Shane661 on 13 Dec 2008 17:33
Personally, I calculate rpm vs. wheel speed using gearing calculators, wheel circumference, and a small percentage modifier in order to account for slight wheelspin or clutch slip. It has proven very accurate, to within about .5% at Maxton.
In the drag racing application it should be much easier to see the slip than to detect the relatively slight amounts encountered at top speed.
Shane
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Shane661
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posted December 13, 2008 09:35 AM
Scott, I am not certain about using the speed sensor of the bike for your purpose. Several people are logging this data at Maxton, but I believe they are using an additional pick up.
Shane
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flite leader
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posted December 13, 2008 09:43 AM
yeah but if you read the orig post
he said he wasnt interested......................a flawed approach
& at maxton many racers are experiencing 8-9 percent wheel slip
thats lost traction.........................................
think if that were transmitted into foward motion
easily a record in most classes
if you had 8% more HP
8% better aerodynamics..........or reduction in CD
& 8% better traction everyone would think you cheating
if not at least youve discovered the holy grail of racers
it seems like an insignificant number...........really depends on where you use it
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Shane661
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posted December 13, 2008 10:05 AM
Nobody at Maxton is seeing 8-9 percent wheel slip through the traps. That would equate to 16 mph at 200 mph.
You may see an occasional exception when a 600 hp turbo blows the tire away, but otherwise, no way.
Shane
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flite leader
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posted December 13, 2008 10:19 AM
quote:
Nobody at Maxton is seeing 8-9 percent wheel slip through the traps. That would equate to 16 mph at 200 mph.
You may see an occasional exception when a 600 hp turbo blows the tire away, but otherwise, no way.
Shane
ok if you insist
at the lamborghini test trackthey see similar numbers
most that try to see or brak 200 mph are aware...........pushing a lot of air
if you go out to the last few hundred feet b4 timing you will see
tyres are printing..............black marks
no less vincent hill & others have mentioned traction a problem
& you are correct in the math....... the very point i wanted to makes
no less at bonneville i think Doug might concur
no less the surface varies almost every year
if you seen it hard......softy.....slushy...........
even hard it can be so rough as to make you eyeballs bounce around
almost like running on agravel country road
salt aint asphalt
simply a loss of traction
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almost_les
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posted December 13, 2008 10:26 AM
should be pretty simple if you can log it. just graph it out on excel or whatever, have rpms on the x axis and wheel speed on the y axis and you should get a couple lines, anything that isn't linear would indicate clutch slipping. you could even use some basic calculus to figure out the curvature at any given point to figure the exact amount.
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flite leader
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posted December 13, 2008 10:34 AM
motoGP guys do this all the time
& they been loggin & analyzing this info since forever
coming up off a turn laying down HP
[ even they are aware of % wheelspin slip on usually pristine track]
wheelspin & the associated 1/2 ways they have for traction control
this is old news
my point is on the orig post he stated engine & clutch with disregard to wheel rpm
simply a flawed approach
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Shane661
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posted December 13, 2008 10:48 AM
Edited By: Shane661 on 13 Dec 2008 18:51
He really doesn't need to know wheel speed to determine clutch slip. Per gear, the relationship of rpm to output shaft speed will remain constant...unless there is clutch slippage.
For example, if 1st gear is x countershaft revolutions/1000 rpm, that will remain a constant unless RPM exceeds countershaft speed, which is clutch slip (all he wants to monitor right now).
Shane
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flite leader
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posted December 13, 2008 11:05 AM
i agrre shane.....& wheel speed & wheel RPM are essentially the same
yet if the clutch is locked tight & the wheel is slipping.........
you would have to show a differential at the clutch..........very difficult to do
[not impossiblr]
id almost be willing to bet its easier to log wheel rpm
as opposed to primary gear rpm
for the sake of a starbux conversation .................................you are right
& if we wanted just the cerebral ............no less everything is possible
yet practical reality = a headache & very little info
slipper clutches have been nset up for decades without any electronic needs
in fact its very much a guesstimate
your clutch a midday practice aint the tyre .....clutch ot motor you will have
for evening or nite time run offs........................& there NO way to mathematically index it
you will make changes apprx every 2 hours ! ! ! ! ! ! !
or you will be going home early
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KZScott
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posted December 13, 2008 11:47 AM
the main point is to see where the clutch is slipping in first gear(and if its slipping on the top end with nitrous). I have a lock up set up very similar to a slider, only its hand operated. flite you seem to have little drag racing background. I pop the lever off the line and the lock up takes over slipping the clutch the right amount and eventually locking in fully (all of this happens in first gear) there is no slip in second or any other gear unless its at max rpm if i dont have quite enough weight on the arms.
my approach is what i want. one step at a time I allready log AFR, RPM and TPS. its not flawed  keep your degrading opinions to yourself, im not interested in wheel spin. im not on SALT. first you say Maxton, then Bonneville. stay on topic or stay out of the topic. if you knew anything about tuning a lock up in first gear you would know we are talking about drag racing not motogp or lsr. in lsr the purpose of a lock up is for the top end not first gear.
Paul gets it, Shane gets it, Vic gets it. try to stay focused on the topic at hand and dont go of on random tangents untill the discussion is over. or just dont reply to my topics if you insist on talking about unrelated events. this is getting really annoying....
Shane, I believe Karl had something to measure wheel speed at one time before he upgraded to the DL-32. Im pretty sure that was using the factory speed sensor and some sort of box RR made and I think connected to the GPS (other wise it would only work for 1 gear). the sensor is there, the bike knows how to tell how fast that shaft is spinning, i just need the LM-1 to know too. there has to be a way without putting another sensor on it
Dont worry Paul, I can tell them if I added or removed static pressure or weight and they wont know where im really at without knowing the baseline. especially if i dont tell them how much was added or removed  Nox is going to want one of these if I get it figured out, he could tune way faster
____________
01 ZX-12R 8.84 @ 156.3 no bars, DOT tires. Pump Gas, NA.... turbo 8.47 @ 164.
00 ZX-12R 8.62 @ 165.2 no bars, slicks, Pump Gas, 55 shot.... turbo 8.32 @173
00 ZX-12R Fastest NA Kawasaki in the world 1: 222.046 1.5: 226.390 Loring AFB
00 ZX-12R street turbo 1: 227.9 1.5: 234.1 Loring AFB
00 ZX-12R LSR turbo 1: 263.1 1.5: 266.5 Loring AFB Worlds fastest ZX-12R
CMG Racing RCC Turbos
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flite leader
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posted December 13, 2008 12:00 PM
Edited By: flite leader on 13 Dec 2008 20:10
quote:
the main point is to see where the clutch is slipping in first gear(and if its slipping on the top end with nitrous). I have a lock up set up very similar to a slider, only its hand operated. flite you seem to have little drag racing background. I pop the lever off the line and the lock up takes over slipping the clutch the right amount and eventually locking in fully (all of this happens in first gear) there is no slip in second or any other gear unless its at max rpm if i dont have quite enough weight on the arms.
my approach is what i want. one step at a time I allready log AFR, RPM and TPS. its not flawed keep your degrading opinions to yourself, im not interested in wheel spin. im not on SALT. first you say Maxton, then Bonneville. stay on topic or stay out of the topic. if you knew anything about tuning a lock up in first gear you would know we are talking about drag racing not motogp or lsr. in lsr the purpose of a lock up is for the top end not first gear.
Paul gets it, Shane gets it, Vic gets it. try to stay focused on the topic at hand and dont go of on random tangents untill the discussion is over. or just dont reply to my topics if you insist on talking about unrelated events. this is getting really annoying....
Shane, I believe Karl had something to measure wheel speed at one time before he upgraded to the DL-32. Im pretty sure that was using the factory speed sensor and some sort of box RR made and I think connected to the GPS (other wise it would only work for 1 gear). the sensor is there, the bike knows how to tell how fast that shaft is spinning, i just need the LM-1 to know too. there has to be a way without putting another sensor on it
Dont worry Paul, I can tell them if I added or removed static pressure or weight and they wont know where im really at without knowing the baseline. especially if i dont tell them how much was added or removed Nox is going to want one of these if I get it figured out, he could tune way faster
dude it nothing new about a slider or lock up clutch
theyve been around for decades
& if its slipping any gear past 2nd youve got it set up wrong ! ! ! !! !!!
pee wee gleason & ricky gadson perfected launches by maniplulating
their clutches off the line.........or loading & slipping during the launch
the very first lockups were used on harleys..........................o let me see the last 20 years !! !
no i know not of what you speak of
but i do know any clutch you have its its slipping more than have way thru 2nd gear
AINT RIGHT
now a days theyare mostly used by riders that are used to throwing away the clutch
as opposed to riding out of the hole
whatever you style electronic babysitting aint goin to make you faster
you already stated its slipping up top
its set up Wrong !
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or break your ass...!!
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KZScott
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posted December 13, 2008 12:13 PM
Edited By: KZScott on 13 Dec 2008 20:14
its not slipping up top or in second . read what I just posted!, it only slips up top if theres not enough weight on the arms. I havent had it slip up top yet. but if i take weight off or add more power it might. if its doing it a tiny bit you may not feel it, but the data logs would pick it up, letting you know to put more weight on it. its locked in in second. I throw away the lever on the line. monitoring slip lets you fine tune it better and will make you quicker. you obviously havent tuned a lock up for drag racing, stay out of this topic. I dont need a history lesson, and sure as hell dont need your help to set up a clutch.
____________
01 ZX-12R 8.84 @ 156.3 no bars, DOT tires. Pump Gas, NA.... turbo 8.47 @ 164.
00 ZX-12R 8.62 @ 165.2 no bars, slicks, Pump Gas, 55 shot.... turbo 8.32 @173
00 ZX-12R Fastest NA Kawasaki in the world 1: 222.046 1.5: 226.390 Loring AFB
00 ZX-12R street turbo 1: 227.9 1.5: 234.1 Loring AFB
00 ZX-12R LSR turbo 1: 263.1 1.5: 266.5 Loring AFB Worlds fastest ZX-12R
CMG Racing RCC Turbos
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flite leader
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posted December 13, 2008 12:24 PM
i read what you posted.......
it might go into low earth orbit if it were inside the space shuttle
not used to tryin to discern ifs ......ands......... & maybe's
if you are talkin about possibilties....... [not what i was getting from what you wrote]
yes anything is possible
on the other hand i thought you were problem solving........
altogether a different form of reasoning
why state or talk about something if it doesnt apply..........
no less if thats not what you are dewaling with in reality
like i said lock ups are not new
if you get more traction as the ttrack gets cooler.......more HP as the day goes on
the electronic do hickey wont tell you what to do...........................
you will have to compensate
something electronic is going to tell you that........ no way
or as you might indicating now .........you want to keep the SAME amount of slip
as conditions change
is that true
history lesson
help
i didnt offer you either
you post stuff that is very flawed.......... very
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Stuart Racing
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posted December 13, 2008 01:42 PM
Hey it`s not like we are racing for hours or miles at a time...Our races are over in mere seconds then we go back and make changes as needed if needed.....The electronic duehickey would let us know wich way to go....Then wait to make a few min.`s to make the next pass....(not hour`s or miles)GP RACING.ect. ect.ect......Dragracing, if a mistake in adjustments are made,it can be changed....In road racing, you`re stuck with what tune up call you made at the start.....Yes lockup have been around for years, but for what we have and the way we use it (not millionaires),we get the best use of it for this type of racing....The electronics will only help out on Scott`s setup....No big high dollar racing operations with us.....JMO.....
Paul.....
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flite leader
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posted December 13, 2008 01:53 PM
from the time you & every body else races
sure it takes hours unless you have the strip to yourself
& an electronic gismo wont tell you what to do after the sun goes down.....track temps go down 30 degrees.......humidity goes up & you runnin close to sea level
what do you do ............................... please Tell inquiring minds want to know
no more than a tyre gauge tells you what to do........it only tells you how much ! ! ! ! ! ! ! ! !
if you add or subtract its as much as an educated guess or luck for most
ALL the drag racers i know that ARE successful keep a log of actual factors
no doubt nowadays thats a Cd or flashdrive but still retained info
& when condtions get close they use that as a baseline
having an accurate tyre gauge counts for Much in Nascar when sometimes
as little as 1/4 PSI makes the difference in winning & just being in the top 10
or drag racing making a 60ft time or not
f1 & nascar datlog as much as anyone....................only gives them a referenceon
most of those calls on top of the pit box are digested info
not some gizmo flashing leds at someone..........................
cept maybe they are about to run out of fuel
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entropy
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posted December 13, 2008 02:29 PM
Edited By: entropy on 13 Dec 2008 22:36
geeze, flite, you are going into orbit about simple stuff. It would be cool if you would carefully read Scott's post, then see if you could stay focused while you answer. I'm feeling you are correct in most stuff, just get "tangled up in yr shoelaces" when responding.
Scott,
the speed sensor "counts" teeth on an output cluster gear and sends a digital signal to the ECU.
You are correct, RR built me a digital to analog converter and for a time i did log wheel speed using the LM-1. This really measures rpm of the output shaft equivalent to x * rear wheel speed.
The intent was to monitor clutch slippage for 1/4 mile, but really didn't work out well because:
1. the Innovate boxes only take 10 samples per sec and it is difficult to see a correlation of rpm increase and rear wheel speed/clutch unless the slippage is really pretty big. Gotta assume the r wheel is not slipping, bc both clutch slippage and rear wheel slippage show up as an increase in rpm of the speed sensor.
2. to most easily isolate clutch slippage as opposed to rear wheel slippage, you really need to assure that the rear wheel is not spinning/slipping.
3. to most easily isolate wheel slippage you really need a sensor on the front wheel and use the speed sensor for the back.
I finally figured that my 10 samples per sec logging set up wasn't really up to that set of experiments.
Shane,
i think you might be having a lil more tire slippage on the big end more than you think, but the slipping is being masked by tire growth. Next time you go to the dyno spin it up one time without strapping the bike down. Put a tape measure on the r axle nut (BRAKE SIDE!!!!) as you go from 2000 rpm to 10,000...
We did this a JohnnyCheese's one time, Johnny LOVES experiments!
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Shane661
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posted December 13, 2008 02:32 PM
Edited By: Shane661 on 13 Dec 2008 22:37
quote:
Shane,
i think you might behaving a lil more tire slippage on the big end more than you think, but the slipping is being masked by tire growth. Next time you go to the dyno spin it up one time without strapping the bike down. Put a tape measure on the swingarm (BRAKE SIDE!!!!) as you go from 2000 rpm to 10,000...
We did this a JohnnyCheese's one time, Johnny LOVES experiments!
I know there is some slippage, Karl...but not 16 mph worth. That is close to 3 gear teeth in top gear.
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entropy
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posted December 13, 2008 02:37 PM
Edited By: entropy on 13 Dec 2008 22:38
i get about 3.5%slippage near as i can tell.
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Shane661
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posted December 13, 2008 02:39 PM
Edited By: Shane661 on 13 Dec 2008 22:41
You would be seeing about 4+" of slip per wheel revolution, even with tire growth to come near 8%. I lose about 5 mph at near 191..which is closer to 2.5%. You bike is pretty long, which may give it more slip than mine.
Nonetheless, 8% would be tremendous.
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entropy
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posted December 13, 2008 03:02 PM
quote:
You would be seeing about 4+" of slip per wheel revolution, even with tire growth to come near 8%. I lose about 5 mph at near 191..which is closer to 2.5%. You bike is pretty long, which may give it more slip than mine.
Nonetheless, 8% would be tremendous.
yep, my heap is a bit too long
I agree 8% seems like w-a-y high for an asphalt track.
Hey, MR Shane, are you and yr lovely sidekick gonna come to Texas this year??
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