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Discussion Starter · #1 ·
Well, I just rode the bike for the first time with the 14:1. I have to say, I love it. It turned the bike into a torque monster. It trys to pull the wheels in almost every gear if you hit it at the right time. To me, it feels like it makes a lot more torque at any point in the rpm range. It doesn't feel a whole lot faster, but it definetly has more grunt. I was also running in sand/ soft dirt, on the stock tires, so the lack of traction could make it decieving as well. I can't wait to get my paddles on it, and go run some hills. That will be the true test.
 

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sounds like a much better improvement over the 13:1 GYTR... now go smoke sum people! :rock :yfz
 

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I've been thinking of doing the same but have a few questions:
What fuel are you running?
How do you start electric or kicker?
Is it hard to start?
What other mod are you running?
Did you re-jet, and what is your jetting / altitude?
How does it change the exhaust note?

I'm thinking about doing the Boondocker Nitros kit but then I won't be going
with the 14:1
 

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Discussion Starter · #5 ·
What fuel are you running?
VP C12
How do you start electric or kicker?
Electric
Is it hard to start?
Not at all, usually starts on the first try
What other mod are you running?
UM airbox with K&N, Alba Pipe, Cam Mod
Did you re-jet, and what is your jetting / altitude?
180 main, 48 pilot, 4th clip ncvq, 1.25 turns on air mix screw. Alt is between 100-500ft, depending on where I am riding.
How does it change the exhaust note?
I can't really explain how it sounds different, but the sound has definetly changed a little. Maybe a little meaner sounding? I don't know.
 

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Could you please give more info on VP C12
Octane level? Where to get it?

Geoff.
 

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Discussion Starter · #7 ·
Originally posted by Aussiequadrider@Feb 22 2004, 10:37 AM
Could you please give more info on VP C12
Octane level? Where to get it?

Geoff.
C12
Recommended for compression ratios up to: 15:1 will satisfy the needs of 75% of today's race engines. Used in: Oval track, drag race, MX and endurance competition. Race cars, race boats, motorcycles, Personal WaterCraft and karts. Has won Modified Tour, GNN, D.I.R.T., Indy Lights, NHRA, AMA, and other local and national championships from coast to coast and around the world.

• Color: Green
• Leaded
• Motor Octane: 108
• Specific gravity: .717 at 60° F

Link to VP page
 

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Are you just running the C12 straight or mixed with like 91?If mixed,what percent?Did you have to jet up after you put the 14:1 in?Is there a difference in how many miles you get on a single gas tank?

Thanks
 

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Discussion Starter · #9 ·
Originally posted by 2000racing@Feb 22 2004, 11:42 AM
Are you just running the C12 straight or mixed with like 91?If mixed,what percent?Did you have to jet up after you put the 14:1 in?Is there a difference in how many miles you get on a single gas tank?

Thanks
Straight c12, and I went from a 175 main to a 180, and a 45 pilot, to a 48. Seems to run well. As for mileage, I have no clue. I don't usually ride far enough to worry about it.
 

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see, i would love to get a higher comp piston. but then my gas prices will about triple.
the only thing i dont like about it is paying 5 bucks a gallon for fuel.

but im jealous dude. i want that.
 

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My 14:1 will be here on Tuesday.

How does it rev now? With my 13:1 I had the same results as you, more torque, but did not seem to "rev" as good.

Oh well I will see how the 14:1 is and if I don't like it I will pass it on also.




And whoever said they wanted a 14:1 and then nitrous, you are asking for trouble. Boost or nitrous both need lower compression to do right and not explode. Any other questions please ask away.
 

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Discussion Starter · #12 ·
Originally posted by Pahrump@Feb 22 2004, 11:27 PM
My 14:1 will be here on Tuesday.

How does it rev now? With my 13:1 I had the same results as you, more torque, but did not seem to "rev" as good.

Oh well I will see how the 14:1 is and if I don't like it I will pass it on also.




And whoever said they wanted a 14:1 and then nitrous, you are asking for trouble. Boost or nitrous both need lower compression to do right and not explode. Any other questions please ask away.
It definetly does not rev quite as freely as before. This seems more apparent on deceleration. But, that could change a little as the motor breaks in more. Also, I suppose a lighter flywheel could help as well. I think the added torque outweighs the slightly slower revs.
 

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Originally posted by 24v@Feb 23 2004, 04:29 AM
It definetly does not rev quite as freely as before. This seems more apparent on deceleration. But, that could change a little as the motor breaks in more. Also, I suppose a lighter flywheel could help as well. I think the added torque outweighs the slightly slower revs.
I have the -4 flywheel on order from TrailTech as we speak, they are only $119 bucks. I need it cauce I want to take my battery off but the DynaTek ignition needs more juice than the stocker so therefor it willnot start without the battery.


But a fix is with the better flywheel and a 4700 capacitor in place of the battery. And I am sure it will help the bike rev out better also.
 

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they make a 14:1 compression 450 kit for the yfz....the yfz stock with a pipe is fast....let alone all this other stuff plus that kit...i can't even imagine how fast that would be.
 

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Discussion Starter · #15 ·
Originally posted by YFZ-TRX450racer@Feb 23 2004, 11:29 AM
they make a 14:1 compression 450 kit for the yfz....the yfz stock with a pipe is fast....let alone all this other stuff plus that kit...i can't even imagine how fast that would be.
Yeah, but you are looking at a minimum of $260 more, plus shipping both ways, for a mere 10cc gain. Seems a little steep for me for the 1-2hp gain.
 

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Originally posted by 24v+Feb 23 2004, 11:50 AM--></span><table border='0' align='center' width='95%' cellpadding='3' cellspacing='1'><tr><td>QUOTE (24v @ Feb 23 2004, 11:50 AM)</td></tr><tr><td id='QUOTE'> <!--QuoteBegin--YFZ-TRX450racer@Feb 23 2004, 11:29 AM
they make a 14:1 compression 450 kit for the yfz....the yfz stock with a pipe is fast....let alone all this other stuff plus that kit...i can't even imagine how fast that would be.
Yeah, but you are looking at a minimum of $260 more, plus shipping both ways, for a mere 10cc gain. Seems a little steep for me for the 1-2hp gain. [/b][/quote]
10-4 good buddy
 

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I have the 14:1 , It made my YFZ a real torque monster. I went up on the main jet with the C12. The sound has changed slightly. The 14:1 piston is awesome, but I'm tearing it down again and going to port the head and add 20 more cc's. Hopefully I 'll have it back together soon.

I wish there was a Honda 450 around this area. :lol
 

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Discussion Starter · #18 ·
Originally posted by YammerHammer@Feb 24 2004, 05:06 PM


I wish there was a Honda 450 around this area. :lol
No you don't. It isn't even a race if your YFZ is built at all. :sonic
 

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i have a question regarding nitrous and high compression in a quad i would like to know the reason why you can't do it? we run 15-16 to 1 in our race car and spray 500 to 700 hp of nitrous. if you have a quality piston and strong rod and run good fuel 118 and pull the timing back. i dont know why you would have problems? only problems i have ever heard about was bending rods.

our cr500 has 210 psi compression roughly 12 to 1 and we run nitrous no problems but it 2 stroke

i agree on the turbo needs low compression due to boost.


i believe the trinty raptor kit is 13 to 1 and have 40hp of nitrous on it. and runs a je piston and carillo rod.
 

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Detroit, you can run a high comp piston with the N2O but the problem is as soon as you spread the word that it can be done someone will try to run a 20 shot on their 13:1 GYTR piston and there will not be anything left of it.

It can be done with proper fuel and proper timing management.

The timing part is where most folks will not be able to do it, I for one can with the Dyna box.


BTW just helping ya out fix the KIT STARTER in your sig to KICK STARTER.

Later Scott
 
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