Heavy AK
Novice Class
Posts: 64
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posted December 28, 2007 07:25 PM
Max Torque or Max horsepower
For a top speed run is it better to shift just after peak horspower or peak torque? I ask this because I'm not sure that winding out the throttle is the best method to get to max speed. I run a '00 ZX-12R and we have a mile and a half straight to play with. I don't seem to be getting the best results by shifting at 11500...it just doesn't seem that I'm reaching top speed.
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A little GAS is a good thing!
  
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woppi
Pro
Posts: 1362
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posted December 29, 2007 09:24 AM
my mine:
at first -
look at your oil - that there is enough in your engine !!!!!
i have seen many destroyed german zx12r engine´s !!!!!!!!! many !!!!!!!
they are riding full throttle half an hour on there freeway´s -- and then -- PEEEEENNNG
the 2 or 3 rod want take a look out of the case !!!
i would shift at 11700 - 11800 rpm
take a look at your air pressure ( tire), demount your mirror´s and turn signals
do you have an air shifter ??
woppi
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1st TFA Member / Austria !
" if it has wheels or titts - sometimes you will get troubles "
2000 Limited ZX12R NOS
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shiphteey
Needs a job
Posts: 2529
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posted December 29, 2007 02:31 PM
For a top speed run is it better to shift just after peak horspower or peak torque?
---While I don't have an exact RPM for you, part of when you shift on the 12 depends on whether or not you have a stock exhaust. An aftermarket exhaust not only makes more power but holds peak power over a longer period of time, whereas RPM close to the limiter really have the stock piped 12 falling on its face in terms of HP.
I ask this because I'm not sure that winding out the throttle is the best method to get to max speed. I run a '00 ZX-12R and we have a mile and a half straight to play with. I don't seem to be getting the best results by shifting at 11500...it just doesn't seem that I'm reaching top speed.
----Personally, I shift as late as possible, about 12k indicated, on my 2000. 12,200 indicated is about 11,600 actual, which is the rev limiter. What is your weight if you don't mind me asking? As woppi mentioned ditch the mirrors and signals. Lube the chain well, not too tight and if its really 1.5 miles you should have your bike pretty much tapped out. Do you remember what RPM you are seeing tapped out in 6th? Are the RPMs still rising at your shutdown point? We can help you figure out what your actual MPH is depending on your tire size, sprockets (presuming stock so 18/46) and RPM. Try and be accurate with what RPM you claim to have seen...as 100 rpms is more than a 1 mph variance deep in 6th. But for a stock to stock-ish zx12 and an avg guy, 180-anything is pretty respectable IMO.
A.
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Heavy AK
Novice Class
Posts: 64
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posted December 31, 2007 11:22 AM
I have a full Muzzy Exhaust, K&N airfilters, PCIII USB and I weigh 267 pounds I am now running 17/46 gearing and I have run it to 11500 in 6th. I run the Bridgestone BT014 tires and I flop between the 190 & 200 rear tire. I usually run 36-38 front and 38 - 40psi rear.
Last year I was 250 lbs with the same setup running 18/46 gearing and I could only run it to 9,500 - 10,000 rpms in 6th.
Any tips helpful...
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shiphteey
Needs a job
Posts: 2529
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posted January 01, 2008 07:40 AM
267 lbs....you are a BIG GUY THERE! That is part of the problem, no offense! Its hard for BIG GUYS to get down and out of the wind! It is
RARE
for almost ANYONE even in the best conditions to pull to the stock rev limiter in 6th with just the mods yo've mentioned and stock gearing. Doug Meyer has just about or basically has done it, Jason McVicar has too, but these are highly experienced riders who aren't 267 lbs.
11,500 RPMS in 6th gear with 17/46....you were in the 170ish mph range! LOW 170s! You have about 700 more RPMS indicated on your tach....
17/46 is good for roughly 183 mph, give or take a little.
17/46 to 18/46 is a significant difference. Can you get your hands on a 45 and 44 tooth? You can still use the stock chain.
I'm wondering if 17/46 has you pulling past peak HP too much (harder for your 12 to do with your weight and aeros than say my 115 lb ass) and 18/46 has you almost pissing in the wind.
Given your mods and size, maybe 17/45 or 44 may yield you the highest actual MPH, but you'd need a way of measuring this. I just picked up a nice GPS from ebay for about $50.
Just as an aside, here is my inexperienced Bonneville tuck.
Even then I'm probably out of the wind a lot more than you! After you play with gearing you'd probably need to work on your aeros or add HP, no way around it.
Best of luck, check everything twice and be safe bro.
Ali
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aliveagain
Needs a life
Posts: 5033
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posted January 01, 2008 03:46 PM
Damn Shiphteey,my stomach ends about where your shoulders are!
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I wondered why the baseball kept getting bigger. Then it hit me.
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shiphteey
Needs a job
Posts: 2529
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posted January 01, 2008 05:56 PM
lol
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Heavy AK
Novice Class
Posts: 64
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posted January 02, 2008 04:47 PM
Yeah...I know that the whole weight thing is a problem...as is my shoulders in the wind. I intend to get the Muzzy 1270 kit this winter and add that little bit of extra grunt...hopefully it'll push me into the 190mph range or at least get me up to speed faster. The reason I haven't went down to 17/45 gearing is because I thought the bike would take longer to ge there with that gearing...I know you gain quickness by dropping one tooth in the front and gain top speed by dropping one in the back but I thought I would take me longer to get there by dropping one in the back. I intend to get a 46 tooth Vortex rear sprocket to drop some weight.
I'm really hoping to get up to speed quicker without sacrificing too much top speed. I run a lot of races against GSX-R 1000, ZX-10R, CBR 1000s and Hayabusas most of those guys are 150-170ish people...they jump out to about 3-4 bike lengths as soon as we shift into 3rd and I have to reel them in at the end....
There's only one person who is my weight and he rides an 06 Busa....we tend to run damn near identical...the winner usually wins by half a bike length.
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shiphteey
Needs a job
Posts: 2529
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posted January 02, 2008 05:37 PM
 Edited By: shiphteey on 2 Jan 2008 17:38
Yeah...I know that the whole weight thing is a problem...as is my shoulders in the wind. I intend to get the Muzzy 1270 kit this winter and add that little bit of extra grunt...hopefully it'll push me into the 190mph range or at least get me up to speed faster.
----Headwork while you're at it otherwise you may be a little disappointed with just a drop-in piston kit. Hell a 30-40 shot on the top end would be fine for the 12 and offer much more thrust up top when you feel aeros are really slowing you down.
The reason I haven't went down to 17/45 gearing is because I thought the bike would take longer to ge there with that gearing...I know you gain quickness by dropping one tooth in the front and gain top speed by dropping one in the back but I thought I would take me longer to get there by dropping one in the back. I intend to get a 46 tooth Vortex rear sprocket to drop some weight.
----Right, I was just thinking maybe your aeros are holding you back to the point where 17/46 is a little past peak power and the bike can't keep pulling there with 180+ wind and your body out there. Maybe 17/45 will yield you a higher actual top speed ... if it hangs at the same RPM then that should be a few mph more! But I hear ya....until I could personally wring out 17/46 on the rev limiter or at least deep on red I'd keep at it too. Careful with Vortex Aluminum. They sharkfin very quickly! There are other light sprockets that last much longer than them.
I'm really hoping to get up to speed quicker without sacrificing too much top speed. I run a lot of races against GSX-R 1000, ZX-10R, CBR 1000s and Hayabusas most of those guys are 150-170ish people...they jump out to about 3-4 bike lengths as soon as we shift into 3rd and I have to reel them in at the end....
----You have said quite a bit there! "Top Speed". If the top speed is theoretical (196) that you can never hope to achieve given your current set-up, then it means NOTHING and you would have been better off with shorter gearing than 18/46. Going -1 would help with the liters....but as you said they jump out on you 3-4 bikes....SIGNIFICANT on the streets! Have you considered 16/46? Gearing would be on the extreme side, but a true 170 mph on the rev limiter should be doable, although not much more. Since you said 170-ish, I would recommend to you 16/45! Sounds PERFECT! You still use your stock chain it if itsn't too stretched.
There's only one person who is my weight and he rides an 06 Busa....we tend to run damn near identical...the winner usually wins by half a bike length.
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TRNorBRN6001
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Posts: 2021
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posted January 03, 2008 09:36 AM
Yep, I hear ya. It takes a lot to get big fellas moving and then you have the bad aeros.
I'll have to find a pic of my bro at the Texas Mile, its kind of funny. He is 6'6" and at least
150-175lbs heavier than my little 250-260lbs.
His best is around 185mph. We picking up a sloped tank (Thanks Jon Amo) to get him tucked a little better.
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shiphteey
Needs a job
Posts: 2529
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posted January 04, 2008 06:56 AM
For Comparision.....TX MILE tuck:
A.
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TRNorBRN6001
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posted January 04, 2008 08:21 AM
Thanks Shiphteey, that's my Brother. Notice the svelte tuck!
It's taken him years to bulk up so he could create his own mobile
balast system and keep that rear tire from slipping at speed.
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entropy
Moderator
Posts: 8671
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posted January 04, 2008 02:18 PM
Robert = 3.5 Ali's
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osti33
Needs a job
Posts: 2973
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posted January 04, 2008 06:34 PM
quote:
Yep, I hear ya. It takes a lot to get big fellas moving and then you have the bad aeros.
I'll have to find a pic of my bro at the Texas Mile, its kind of funny. He is 6'6" and at least
150-175lbs heavier than my little 250-260lbs.
His best is around 185mph. We picking up a sloped tank (Thanks Jon Amo) to get him tucked a little better.
Gary,
If your bro is 6'6" I must be getting shorter.  I am 6'5" and about 6'6" with shoes on and he is at least a couple of inches taller than me.
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osti33
Needs a job
Posts: 2973
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posted January 04, 2008 06:35 PM
quote:
Robert = 3.5 Ali's
+1
LMAO!! 
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lietoome
Needs a job
Posts: 2033
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posted January 04, 2008 07:18 PM
Edited By: lietoome on 4 Jan 2008 19:19
Make sure you remove your kneesliders, they cause excessive drag
---inside joke w/ Ali. Listen to him, he (and the other 'Milers') has a lot of knowledge on going Faster. Looking forward to the next trip to Goliad.
BTW, I'm XXL too. Gearing is the key.
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shiphteey
Needs a job
Posts: 2529
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posted January 06, 2008 08:19 AM
Funny stuff guys! 3.5....dayum! Then again, I remember a while back ... 2 years or so ago I had a run against an LAbusas board memeber....275 ish RWHP Turbo Busa....against my small shot nos 12...I rememeber stating my weight and he said he was double my weight. So here I go, calculating power to weight....trying to figure the best gearing for our run...I think I rolled up with 17/46....meet up w/him, and he's TRIPLE! Even from
4,000 rpms in 6th gear, about 70 mph.....roll-on OFF spray I walked away....
On spray 9k 2nd gear as soon as I clicked 3rd it was over, partly due to turbo issues.
The weight matters!
A buddy on a bone stock 04 cbr 1000 who weighs 40 lbs more than me always gets toasted as soon as I click 3rd....when we swapped....we LOCKED
LOCKED!
till early 6th....
I didn't think that would happen! Anyways, I hope maybe its inspirational for some of you big guys to drop ... hell even 20 lbs will be noticable in the Standing Mile.
But between Aeros, HP and gearing....if you feel that your aeros can't change much due to your size...then the gearing will help.....but the HP will be needed.
Best of luck to you all again....we're all built differently...he'll I'll never be a pro football player (maybe a kicker??!!? LOL) or serious powerlifter....its all about using what you got. Chances are almost everyone on the board is heavier than me, but I bet most make more money than me too! A little more money into your 12 and that would level the playing field! After all, the goal is ZX12 World Domination.....right?
A.
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Phantom13
Zone Head
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posted January 06, 2008 10:22 AM
Edited By: Phantom13 on 6 Jan 2008 10:23
Heavy AK- Welcome to the wonderful world of LSR!
That being said, here's a few facts and tips you may be interested in knowing.
1. Get yourself a GPS!!!! Without a gps, you have NO CLUE what you're running. A GPS will help you test different tucks and/or modifications to see what's working and what's not.
2. Get yourself to a gym. I was once 250lb's and racing.... I was not very fast. I'm 210 lb's now and I'm MUCH faster due to aerodynamics and sheer weightloss.
3. Get yourself some more horsepower! At your weight, it's going to take roughly 210rwhp to achieve 190mph on GPS..... and that's if your bike is set-up and tuned extremely well and you're very experienced. You won't get anywhere near 210rwhp with a 1270 kit.... you're going to need some NITROUS.
4. Practice, Practice, Practice..... and then practice some more! Try out different things and do as much research on the forums as possible. You'd be suprised at how much you can learn from years of posting by fellow LSR guys.
Just as a little motivation.... my humble beginings were much like yours. I started out on a piped/pc3r/lowered ZX-12R. My first time at the races, I only mustered up 173mph on GPS. I was at 230 lb's back then too. I kept practicing and keeping my eyes and ears open when around other racers. About 50 passes later, I was running 187+mph with the same exact weight and horsepower.... I just learned how to ride it better and how to fine tune my set-up.
Later on, I went on to Nitrous and with a 40 shot, went 194+mph. Time went by and I moved on to a Stage 2 Ace Performance 1287cc engine.... and now I'm running 200mph ALL MOTOR. Next step is putting the Nitrous back on and hitting 205+mph with a small shot.
All you need is persistance and hard work and you'll go as fast as you want in due time.
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before Work is inside the Dictionary."
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TRNorBRN6001
Needs a job
Posts: 2021
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posted January 06, 2008 04:22 PM
Don't get discouraged, I went 195 and heavy change at the mile a few years back on a stock ZX12 motor , foot shifting and a nice shot of juice. I also went 192 or something this last time all motor (not stock!), foot shifting and a bad clutch. You may just need a little something extra on the top end to get ya moving.
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Heavy AK
Novice Class
Posts: 64
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posted January 07, 2008 12:42 PM
Info
quote:
Headwork while you're at it otherwise you may be a little disappointed with just a drop-in piston kit.
And what Headwork would be beneficial with the 1270 kit?
I certainly will take into acount all of the info being shared and I am looking forward to getting back down to 250 by this summer just to see my bike run better. I am thinking of even going to a BMC air filter to run with the new setup.
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A little GAS is a good thing!
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