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How to up the torque on the baby ninja

Posted: Thu Aug 30, 2007 1:00 am
by zxrman
Can somebody tell me? Lol

I have no idea what i can do to up the torque on the zxr?
I just need more torque and dont want to get rid of any top speed or the zxr... Anyone got any ideas? :smt006

Re: How to up the torque on the baby ninja

Posted: Thu Aug 30, 2007 7:18 am
by masterofinsanity
why do you want more torque?

Re: How to up the torque on the baby ninja

Posted: Thu Aug 30, 2007 7:45 am
by Rob636
masterofinsanity wrote:why do you want more torque?


maybe so it can wheelie,

i think some of the racers might agree here, even with money spent on the engine the torque increase isnt going to go through the roof, inline 4's dont generally have much torgue doesnt the zxr have less than 40 torques ?, i think gem knows the answer to that one, but yeah your gonna need a bigger engine for bigger torque figures and if you want a machine that chews rear tyres from imense torque you need a twin,

just be happy you got a bike that can take 30 mph bends quicker than anything else,



Rob

Re: How to up the torque on the baby ninja

Posted: Thu Aug 30, 2007 9:18 am
by rene
you'll find it hard to up the torque loads as torque "genraly" comes from CC what the zxr dosnt have loads of.

best bet is down gearing it you will lose a few mph off the top end tho

Re: How to up the torque on the baby ninja

Posted: Thu Aug 30, 2007 9:57 am
by Rob636
rene wrote:you'll find it hard to up the torque loads as torque "genraly" comes from CC what the zxr dosnt have loads of.

best bet is down gearing it you will lose a few mph off the top end tho




Well said bro

Re: How to up the torque on the baby ninja

Posted: Thu Aug 30, 2007 2:23 pm
by Jamz
Ask any Yank - cc's = torque.

Go on - get it bored out!!! :smt003

The 444cc kit gave me about the same torque at 6000rpm as a normal ZXR has at 14000rpm.

I'm not really one for wheelies, but my few ham-fisted attempts not long before I sold it seemed to get the front up quite nicely off the clutch in 2nd gear. I'm sure anyone with wheelie skills would have found it no problem - but then, you can wheeley a moped if you know how...

Re: How to up the torque on the baby ninja

Posted: Thu Aug 30, 2007 2:27 pm
by rene
peds are piss easy compaired to sports bikes as all the weight is in the back of the bike insted of the front :P

Re: How to up the torque on the baby ninja

Posted: Thu Aug 30, 2007 2:40 pm
by Jamz
Smartarse! :smt019

lol

Re: How to up the torque on the baby ninja

Posted: Thu Aug 30, 2007 3:25 pm
by Rob636
Have You Noooo KnEeEeEeS

Re: How to up the torque on the baby ninja

Posted: Thu Aug 30, 2007 10:12 pm
by Boonie
You get more torque from having a longer stroke in the engine and you get more BHP from having a wider bore. To get more of one you have to sacrifice the other. High BHP engines generally have higher reving engines due to having shorter, wider pistons. They have less travel up and down so produce lots of power at high revs, but when the engne isn't spinning don't do a lot. I believe this is refered to as being over square.

The opposite is a long stroke engine. Under detonation the rear wheel is under force for a longer period, due to valve timings being longer and holding the pressure in longer. However, they don't rev as high due to the longer piston travel. Typically twins are long stroke and 4's are short stroke. Ultimatly the middle ground is a sqaure triple, giving what Triumph feel is the best of both worlds. (I think they actually use a long'ish stroke triple for the 675.)

To give the ZXR400 engine more torque you would need to change the piston stroke. Adjusting the crank pivot position isn't an option without making a new crank case, but you might be able to change the piston rods to longer ones and extend the barrel length with an additional section and another gasget. You'd end up with say a 430cc engine with maybe a slight drop in maximum rpm (down to 12k revs fo safety reasons) but torque might be up by 15%.

I love my book shelf. :smt003

Re: How to up the torque on the baby ninja

Posted: Thu Aug 30, 2007 10:29 pm
by Boonie
...And given that the bike produces maximum power at 12,500 revs it probaly wouldn't drop that much BHP either.

Hmmmmmmmm... :smt017

Re: How to up the torque on the baby ninja

Posted: Thu Aug 30, 2007 10:31 pm
by masterofinsanity
what the f*** are you torqueing about :smt005 you've lost me :smt017

Re: How to up the torque on the baby ninja

Posted: Thu Aug 30, 2007 10:49 pm
by Boonie
:smt003

From a given engine size you can chose to go short stroke & wide bore and have higher BHP (like the new R6 which is gutless below 8000rpm), or you can go long stroke & small bore (thin pistons) and have more torque due to the longer piston travel.

There are ways to assist either configuration you choose to follow and this involves.... Hmmmm, do I write another paragraph about Big Bang configurations? Or maybe go on about the 2007 R1's variable length intakes? Or maybe the benefits of power valves in the exhausts and ram air systems? Ooo-Ooo-Ooo... Or tunable length of exhausts..

LMAO :smt024

Re: How to up the torque on the baby ninja

Posted: Fri Aug 31, 2007 10:07 am
by mycallsevern
I like Boonie he thinks like me :smt003

Re: How to up the torque on the baby ninja

Posted: Fri Aug 31, 2007 10:26 am
by Jamz
What about V4's?

All the revs and top end power of an IL4 with all the low down grunt of a V-twin!

It's just the perfect engine, and I have no idea why nobody makes them for sportsbikes?!

The only thing I can think of is cost of manufacture... or more likely - the fact that they don't ever break, which is bad for the parts business...