Improving Low end Torque

hazy

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For those who had a after market exhaust fitted,did you notice any improvement to your lower end of your RPM range like 3-5k rpm?I'm seriously looking for at option that will helps within these ranges.Most of the times when i view at those Dyno charts,i noticed that is virtually little or no gain at all as compared to a stock exhaust within 4-5k rpm.I am hoping to spend my money wisely where i spend most of the time(4-5k rpm).
 

Dennis in NH

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I added Scorpions to my 2008 FZ6. I really didn't notice any low end torque increase. I did notice mild mid range increase.

On these inline-4 bikes, I don't pay attention to low end torque because I'm not sure they were designed for that. This is where the V-twins come in (e.g., Ducs).

When I had a CBR 1000RR (inline-4), low end torque (specifically, starting out in 1st gear from 0 mph) was noticeably improved by opening up the intake more. It was called the "flapper mod". The idea was that although the intake flapper opened up at 5K RPMs by design, you can make it so that flapper stays open all the time and the extra air helped a bit (even if it wasn't ram air).

For the FZ6 in stock form (and with Scorpions), it seems under 4K is not so great. On the other hand, this makes an FZ6 a reasonable beginner bike because under 4K it's relatively easy to keep things under control.

Dennis
 

urbanj

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Gear it.

Go down one tooth in the front or up two in the rear or do both for ultimate torque increase. Torque applied to the rear wheel is all about gearing and unlike cars or trucks, it's extremely easy to do on a motorbike.
 

hazy

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Gear it.

Go down one tooth in the front or up two in the rear or do both for ultimate torque increase. Torque applied to the rear wheel is all about gearing and unlike cars or trucks, it's extremely easy to do on a motorbike.

This is not what i am looking.Your method just playing with the ratio of the torque,not improving.Maybe a PC3 helps in this area?
 

champion221elite

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Inline 4 cylinder engines are not known for producing large amounts of torque (especially at low rpms). Rather, I4 engines are known for producing good horsepower at high rpms as smoothly as possible.

There are ways to add significant torque to an I4 engine, but it's nothing that's going to "bolt on" in a few minutes. Increasing torque will involve serious engine modifications to the bore and stroke ratio, or the addition of a turbo and intercooler. This will almost certainly involve changes to the stock EFI system including an aftermarket computer, intake manifold, injectors and so on.

Aside from the gearing changes as previously mentioned, there is no such exhaust system that will produce the low end torque you desire. If you're really looking for low end torque, you would be better served by finding a motorcycle that is fitted with a V-Twin engine.
 
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tweak89

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If you're really looking for low end torque, you would be better served by finding a motorcycle that is fitted with a V-Twin engine.

As you don't seem too keen on re-gearing the bike. This is really the only viable solution.

You chose the wrong type of bike if you really have to have that low end grunt.
 
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hazy

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I am not looking for low end torque of a crusier in a fz6,but any method to improve the almost next to nothing torque.I.E by keeping the bike stock or a PC3?

From my best of knowledge,after market exhaust will most likely sacrifice low end for high end HP.
 

RJ2112

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I am not looking for low end torque of a crusier in a fz6,but any method to improve the almost next to nothing torque.I.E by keeping the bike stock or a PC3?

From my best of knowledge,after market exhaust will most likely sacrifice low end for high end HP.

Not trying to sound negative..... the only way to get this motor to have more torque and low RPM power is to sacrifice top end power.

This is exactly what was done to create the FZ6R.... Valves with less overlap, and less lift will increase the intake charge velocity, but seriously strangle the motor 'on top'. Altering the mapping of the FI is not going to increase the low end HP much... maybe 2-5%. Hardly noticeable.

Altering the timing of the valve opening and closing makes the rush of mixture into the chamber much 'crisper', is you shorten the available time to 'fill' the cylinders. That means the air flow has to move faster, through a smaller opening. That rips the droplets of fuel into a finer mist, which burns more completely.

The FZ6 is optimized for 5K-10K RPM use..... compared to the YZFR6 intended use from 7K-12K. That was accomplished by changing the cam timing, and altering the intake tract.

If you want the power band to move to lower RPM than where it is now, it would be most effective to alter the cams again, and get an exhaust with a power valve in it to cork the exhaust at low RPM to keep the charge in the cylinder.

The FZ6R has done most of that already.
 

tweak89

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I am not looking for low end torque of a crusier in a fz6,but any method to improve the almost next to nothing torque.I.E by keeping the bike stock or a PC3?

From my best of knowledge,after market exhaust will most likely sacrifice low end for high end HP.

Your not really listening (or reading). You can't get what you want with minimal changes. Adding exhaust and playing with your fuel map won't change the torque curve. It will give you, at best, a minimal HP/Torque gain...but not where you want it.

Again, changing the gearing is the best and cheapest way to get the feel that you want.

Otherwise, pop a for sale sign on the FZ and look into the myriad of V-Twin powered sport bikes.
 

n3lrk

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A PC3 will help some with low end power (not Night and Day) the other benefit of a PC3 is improved throttle response and overall drive-ability. For dollars spent I thought the PC3 a good deal.
 

stryken

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Again, changing the gearing is the best and cheapest way to get the feel that you want.
.

AGREED... you shouldn't rule this out. Who cares if you are not really getting torque that can be measured on a machine. As long as your body and mind feels an increase that should be all that matters!! :thumbup: You will enjoy it and there is no losses to the bike to do it, only gains.
 
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hazy

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Thanks for all the input,I guess i got to live with it.There is really not much to complain about FZ6 for the money that i spend.Some of the smaller CC bikes available locally costs more than FZ6.

I guess some of you guys do agreed that a little more low end torque will make FZ6 a better bike.
 
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McLovin

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Thanks for all the input,I guess i got to live with it.There is really not much to complain about FZ6 for the money that i spend.Some of the smaller CC bikes available locally costs more than FZ6.

I guess some of you guys do agreed that a little more low end torque will make FZ6 a better bike.

Dude, you dont have to live with it. Changing the gearing is exactly what you are looking for. It is true that pipes/air filter etc will NOT get you any kinda power you are looking for. Riding on high rpm's is also fun, you havent really ridden the fz if you havent taken it above 8-9k IMO
:thumbup:
 

Phil/TX

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Torque is not in the picture with a FZ6, it's like a 125 MX bike Just rev the hell out of it, and row the gear box. If you want serious torque get a Guzzi.
 

OneTrack

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Thanks for all the input,I guess i got to live with it.There is really not much to complain about FZ6 for the money that i spend.Some of the smaller CC bikes available locally costs more than FZ6.

I guess some of you guys do agreed that a little more low end torque will make FZ6 a better bike.

As others have suggested, install a 15 tooth front sprocket and you'll have exactly what you want for about $20.
It's the best bang-for-the-buck performance mod you can do to an FZ6.
 

krid80

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cork it up! Increase your backpressure! This will increase your low end torque at the severe expense of horsepower.

Want torque? As stated before, trade it for a Buell. Want speed? Rev what you got.
 

SeekGod1st

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Dude! Gear the bike, you will get front wheel lifting torque.

It's very inexpensive and puts you in the RPM band on the freeways.

I haven't read one complaint after doing this mod.
 
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