ZX12Girl
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posted November 09, 2001 11:13 AM
Tire Pressure at the Strip!!!
How many lbs. of air pressure are you guys running at the track!!!!
It seems that when I run a lower tire pressure, I am getting awesome traction but slower ET / MPH!!! If I slide all over the track at launch, I am gaining time and mph after the 60ft. mark...
What I am looking for is what lbs of pressure and how that effected your MPH....
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bbirdxx2000
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posted November 10, 2001 05:57 AM
ZX12FIRL I am assuming yourtalking street tire not slick. Anyway I have been doing this for about 20 years (on and off) a couple factors come to play 1- Is the dragstrip a concrete starting block, most are, which you will get better traction. 2-what kind of rear tire a Bridgestone BT-10 is going to stick far better than a Metzeler MEZ4. Lets assume your on a cocrete starting block with a BT-10 O.K. I am also going to assume seeing you are a girl your gross body weight (gross meaning you ,leathers, boots, helment) is about 140-160Lbs. (I appologize if I am way off) this may hurt you because your front end is likly to come up. Solution- kep your gas tank filled to the rim, the extra 30Lbs. of gas is not going to hurt your E.T. on a 160HP. bike.The biggest mistake in dragracing street bikes is everybody backs into the water and does a burnout. Meanwhile while you are aat the staging area all those drops of water are dripping down from your inner fender onto your tire. Solution go around the water then do a dry burnout. Tire pressur your 60-foot time is a great indicator learn how to use it. You do want a lttle wheel spin for momentume and its ok to have the front end come up a little bit 2-6" as long as you don't have to let off on the gas. the lower the tire pressure the more whell resistance you have. to prove this in your drivway take both your tires down to 15LBS . no try to push your bike it will fell like your bike gained 100Lbs. I generally run my front tire pressure at 45lbs. and rear 42Lbs. If you need more traction do a longer burnout By the way you see all these guys smoking their tires in the pit. this is all show .It only takes about 5-10 seconds to heat a tire. so keep that tire pressure up and maybe change to a differant tire and read your 60' feet time 1.70 and under is really good. hope this helps
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MadMike
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posted November 10, 2001 06:16 AM
Hey girl..
Ok depending on the track, if it is loose I run around 12-13 lbs, and if it is sticky I run around 16lbs, and this is with my M/T shootout tire. when I ran the stock wheelbase, I would run between 25-40 depending on traction of the track. and look at your 60 foot times, when you dont spin and your et's are slower then I would say your bogging your motor off of the line you may not notice this but watch and listen to your video's,, and if that is really the case, then maybe you need to soften up your suspension, that will allow the rear to squat instead of spin, try that out and lets see if it helps.
oh and for stock wheelbase bikes almost any GP compound tire is way sticky enough at the track...
Mad Mike
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ZX12Girl
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posted November 10, 2001 09:19 AM
bbirdxx2000
All of your assumptions were correct...
150lbs with leathers.
Concrete pad.
BT010 rear street tire
and I do not get in the water or burn-out!!! I do understand that this doesn't help with street tire traction.
Guess I should have gave a little more info.
I dropped my tire pressure down to like 12lbs and had awesome traction, but my mph did go down as well. I am wondering what the average tire pressure is for the rest of you that run a street tire and what you deal with at the line...(major spin/wheelie/etc,,,)
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bbirdxx2000
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posted November 10, 2001 10:13 AM
your MPH went down because you have abigger contact patch to pushdown the track run higher pressure. post your 60' time ET. and MPH and if the bike is stock I can give you more Imfo. thanks. I run 42Lbs.
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ZX12Girl
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posted November 10, 2001 12:59 PM
 Edited By: ZX12Girl on 10 Nov 2001 13:01
Thanks!!
Here is best to date on my ZX12R (Stock Motor)...
Here is a couple on the Hubby's Busa - My best to date on the Busa is 9.71@151.75
I do leave the line kind of soft......I am working on a more aggressive launch...That's why I am getting some help with starting at the correct tire pressure!!!
I did try the full tank of gas and it slowed me down as well.. On the ZX12R, I am power lifting in every gear...I just ride it out....
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bbirdxx2000
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posted November 10, 2001 01:54 PM
ZX12GIRL, what ever your doing keep doing it!!!! I can't see any flaw with your slips, If I were to nitpick I would say your 60' can come down a hair ( I do mean hair) .05-.10. The only other question I have is where on the tach> are you shifting? A lot of racers shift at redline thinking that were the power peak is. The peak is between 9500-10,000 but by the looks of your MPH I maybe wrong. Youalso have a great weight advantage over most guys 50+ Lbs.Like the saying says "If it's not broke don't fix-it" Your doing great and you would kick my ass. If you do want to SQUEEZE out another tenth try regearing, which is a whole other subject I have a secret on shifting also but I would have to kill you if I tell you. Good luck
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ZX12Girl
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posted November 10, 2001 02:48 PM
Thanks
I have an airshifter and I am shifting at 10,500 on the tach.
I just want to go faster!!!!!!!!!! I wanna see a 9.50ish time slip with a stock motor bike!!!
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bbirdxx2000
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posted November 10, 2001 03:12 PM
Your not going to beleive this but my secret is the Airshifter (MRE)dame your good!!. Your ET does match your MPH, So your next step is to get a few more ponies out of her and still keep it stock I have two Ideas 1) K & N aircleaner and having your throotle bodies sinked at the same time 2) mill your head down to about 30 thousands, will bring your compression up amybe .5 or 20-25 Lbs. per cylinder. If you persue this you will have to run premium gas 93+ octane or booster (carefull with the booster they will eat the inside of your fuel lines) #1 will cost you about $150-$175 #2 about $400 another idea is get a hold of a good machanic and check the cam timming. They should be close to specs If they are off by more than 5 degrees (which I doublt) I will make a slight differance
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ZX12Girl
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posted November 10, 2001 07:38 PM
"Good Mechanic".....Ha, Ha, Ha...... 
Yeah...I've got an awesome mechanic.....I married him!!!!
My engine is top notch as far as Cam timing, Ignition advance, carb sync, etc....
My problem is that I know guys that are running 9.60's on a ZX12R with the same exact mod's as mine!!! And that's what I want to do!!!
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kcadby
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posted November 10, 2001 10:10 PM
Edited By: kcadby on 10 Nov 2001 22:11
Hi Ang...
If the traction is GOOD (VERY RARE) you can run as high as 35PSI Even here at Gainesville though...I usually start a 30 and go down 5PSI at a time till she hooks...
Don't go much (if at all) below 12PSI because you run the risk of the tire coming off the bead if the bike does "something stupid"...
I'm tired as hell from the ProStar race right now so I didn't read everything but...are you shifting your ZX12 at 10,500 or the Busa???
If it's the Busa???never mind...but if it's the Ninja...REV IT HIGHER...Take it to red-line...
The tachs read high so you HAVE to take it to at LEAST 11,500 on the tach for it to run as "quick as it wants to"...11,700 would even be better...
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ZX12Girl
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posted November 11, 2001 08:11 AM
Busa is at 10,500 and the ZX12R at 11,500....
But I do think that I am not as consistant at shifting the ZX12R.
The Busa has a shiftlight...Ya can't really screw that up!!!!
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entropy
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posted November 11, 2001 12:07 PM
my 2 cents for Angi!
As long as folks are giving you free advice, here's mine:
1. listen well to KCadby, MMike
2. get a Dyna shiftlight
3. learn to slip the clutch a bit
4. learn Ron Ayers tel # and clutch plate part #'s
5. lay over the tank till your bosoms are actually on it, stay that way until into 3rd.
6. listen again to KCadby, MMike
I am not implying that Bbird is wrong, just that I have tried to listen to KC/MM and with the same set up you have (add the shift light), I got down to 9.63 (755lb me + bike)
The only thing KC says which I know is right, but I seem to go deaf on is "no hot laps"... 
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ZX12Girl
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posted November 11, 2001 12:26 PM
Edited By: ZX12Girl on 11 Nov 2001 12:27
1. listen well to KCadby, MMike.....Check
3. learn to slip the clutch a bit...Check
5. lay over the tank till your bosoms are actually on it, stay that way until into 3rd........Check
6. listen again to KCadby, MMike...Check
The only thing KC says which I know is right, but I seem to go deaf on is "no hot laps"...Check - Me too
Well 4 out of 6 isn't too bad ....You guys are gonna make me dangerous!!!! LOL
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entropy
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posted November 11, 2001 03:23 PM
I woulda (tried) to give Angia a big kiss!
Angi,
you made my day yesterday, and you surely didn't even know it.
I was despairing over perceived "excessive crankcase pressure", because oil was coming out of my oil filler cap on my newly buily 1361, Some folk on the boards said that excessive pressure is usually due to screwed up rings and I was envisioning a teardown. 
But, I had an inspiration! Check the parts manual which ZX12GIRL aka Angi aka YOU, sent me last year. Yeap (like you say), it showed I was missing an o ring on the cover. Trip to sears automotive and 69 cents later, I was good to go. DOH!
anyway, your kind works follow you, and I thank you: Muuuuuuaaaahhhh! xoxox
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CrotchRocket
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posted November 11, 2001 07:59 PM
Better late than Never...
I run 25lbs. in a Michelin Pilot Sport...I really like that tire!!!
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MadMike
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posted November 11, 2001 09:11 PM
Hey angi,, Kevin is dead on rev that puppy as high as you can, the 12's power is up high... and this may sound weird but on your pcIII map. what are the readings at 100% from oh around 8000rpm to red line, go ahead and just list them off. I made some small changes to mine and I picked up almost a tenth.., also this sounds weird but at my last race in memphis, I was running 144's all weekend long, on my last pass I noticed that my arms were still in my launch position,(you know what I mean I hope). so I pulled them in tight agenst the tank, and I dropped a few hundreths on my et, and ran 1 1/2 mph faster?? I couldent believe it but it was right on the time slip.. oh and entropy. thanks dude!
Mad Mike
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ZX12Girl
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posted November 12, 2001 06:34 AM
Edited By: ZX12Girl on 12 Nov 2001 06:35
That's cool entropy!!!!That book has saved me a couple times as well....Thank God RedElk was sharing!!!!
MadMike,
The last few times that I raced, I did start working on the wind resistance and I lost a tenth as well. But I was drag racing the Busa... I will start paying attention to the arms...(Next Year).
I am putting a list of things together to try out for next season..... So I have now -
1. Learn how to slip the clutch to perfection.
2. Start the tire pressure at 30-25lbs. (I think that I was starting too low.
3. Watch for wind resistance (Arms / Body).
4. Shift just before redline.
Anything else????
What RMP's are you guys leaving at??? I can only leave at 4,000...Everytime I leave at 5,000 (The next step), I am bogging the engine.
Mike - I will get the map numbers when I get a minute at home
Thanks Guys,
I am gonna be freaking dangerous come 2002!!
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RAC4IT
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Bergie
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posted November 12, 2001 05:51 PM
pressure
quote:
How many lbs. of air pressure are you guys running
I run stock D207 @ 32psi. Don't bother lowering the pressure if you're not spinning, and even so on a street radial it doesn't help that much.
Dropping it to 20psi yielded nothing for me. You want to run as much pressure as possible without loss of traction for better MPH.
I see some 'tards putting 15psi in a stock tire and they are complaining about traction and within 5 minutes I bust off a 9.6 w/1.65 60' (stock motor, stock arm) @ 32psi on the stock tire.
Dropping pressure is only necessary if you need it. Might help more on a drag tire though, I couldn't tell you about that since I haven't tried one yet.
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entropy
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posted November 13, 2001 03:59 AM
tire pressure
I run with 41 unless the track is bad, but it usually only takes a few passes of a heavy duty slicked car to put down enough rubber to make the 41psi stick. real soft rear suspension also helps me hook up, but opinions seem to differ on that. I have gone down to 30 if it is real slick, but never lower.
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ZX12Girl
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posted November 13, 2001 05:37 AM
Well....I am not sure.......
I have never been able to run over 25lbs of air with-out spinning.....I mean Bad.....
Maybe its a lightweight thing...I am not sure. But I remember this summer, I tried to leave off 32 and I fishtailed the Busa so badly that I thought I was gonna have a personal introduction to the track.... Then I tried this on the ZX12R as well and it was like riding on a slip and slide......
I always start out around 25 and almost every time, I have to reduce the tire pressure even more....
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entropy
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posted November 13, 2001 05:38 AM
Yeap, you are too skinny. What I did to cure that is go to Popeyes every chance I get!
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ZX12Girl
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posted November 13, 2001 05:47 AM
I can see it now.....
ZX12Girl from Team Lardass has sucessfully increased ET - 10.2@130....Major Sponsors are Popeyes, KFC and McDonalds!!!! Special thanks to Entropy...I couldn't have done it with-out him
LOL....hahahahahaha
I don't think that Kzz1 would care for that!!!!
Too funny!!!!
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entropy
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posted November 13, 2001 05:54 AM
LMFAO!!!!
Hey, Angi, you are really onto something!!!.
Sure, all yr sponsors look great, probably ought to add a Rib Joint and Old Milwaulkee, eh?
But, you pointed out something significant. We have been all trying to do the wrong thing, i.e. DECREASE ET's. Getting lower ET's is harder than hell. Let's see who can get the highest ET's!!!!
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OzRed12
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posted November 13, 2001 07:51 AM
Clutch
Angi, I have found that if I rev too high on launch I end up riding the clutch out more than I should and launching much softer. If I launch at 4-5K rpm it seems I get the right amount of clutch slip/grab on launch. In other words the rpm suits my current ability. I don't think I have the experience to launch harder at higher rpms just yet but practice should cure that.
Half the time I will wheelie the bike for a short distance but will focus on keeping my chest HARD on the tank passed 2nd gear. I am with you on your list of key learnings though. Practice DOES make the difference!
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