Since this is totally unrelated to Mercedes, I put it in the general area.

This winter I'm tearing down my 600cc inline 4 Ninja, and hackjob-ing it into a "streetfighter"
The engine runs on 91+ octane, has 4 carbs, and a redline around 11k

I'm a diesel guy, so all this gasoline junk has me confused.

I have adjusted the valves(all 16!!!!), cleaned and checked the AIR valves (they operate properly), installed new plugs, a new AGM battery, and refreshed the ground straps.

I want more low-end torque(Yes I know the engine is a high-revver by nature) and as far as I can gather I can achieve this by:

Increasing my carb-head runner length from 1" to 4"
Increase my air filter-carb runner length from .5" to 3"
Balance my carbs (1-3, 2-4, then 1/3-2/4)
Add a baffled & more restrictive muffler (currently I have 4 equal length runners going into a straight-through 2" glasspack)

Am I on the right track?

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$60 OM617 Blank Exhaust Flanges
$110 OM606 Blank Exhaust Flanges
No merc at the moment

I'm not sure that you'll ever be able to see a 'low end' rpm gain. I've never heard of anyone wanting to do that for a bike.

Your lengthening the runners might help, but there are some resonance calculations that really should be done first (they are beyond my ME skill...) You might be making them too long and hurting power/tq everywhere in the rev range. Is there an equation or method you used for this ?

Since you are stuck with the factory bore x stroke, is it possible to change cams ? or pay for a new/re-ground cam ? I have no idea what this would cost.

Have you looked into bigger carbs ? (what size are they now - My Katana 750 runs 36mm's, the Bandit 1200's which are closer to your liking run 34mm carbs.)

What year is the bike/motor ? (can't be too new if its carburetted) - EDIT

I don't think its possible to increase the low-end on a motor that is already tuned to rev so high. The bore x stroke affects this curve, as does the cam grind, as does the variables you are changing, but at best, it'll still be a 600cc engine (think suzuki burgman - how much low end do they have?). Is there a 1000cc swap out there for that model year ?

-John

edit - okay, its a 1990. not sure if they made a liter ninja back then or not.

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12006 Jetta Pumpe Duse
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Husband, Father, sometimes friend =)

I have to imagine that someone has been down this road before. Furthermore, there have to be some engine tuners who sell proven components with documented performance gains. Any Kawasaki forums that could be of any help?

Well, I know nothing about Ninja-style bikes, but on Harleys low end torque is all about the exhaust system. See if they make a 4-1 header for the bike or look for some other after market set up that supplies the correct back pressure for low end torque. "Reversion cones" are also and old drag racers trick, they are coned shaped devices that surpress exhaust pulse feed back that robs low end torque.

As far as not knowing of anyone who would want to do this, heck dude, I'll give you one reason: burn outs. Sportsters are built with a bias towards low end torque, that's why they may not beat many "Ninja's" in a race, but they damn sure will burn that back wheel to the rims for any idiot who wants to burn em. There are actually burn-out competitons at some rallys. If that's why you are trying to do this, go buy a Harley and make your neighbors hate you.

Why not just change the sprocket size to take advantage of the power that's already there?

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1983 M-B 240D-Gone too.
1976 M-B 300D-Departed.

"Good" is the worst enemy of "Great".

Or sell it and buy the type of bike you want.

I understand that it isn't a V-twin (That's why I'm saving up for one )
I'm just looking to do some tuning while the bike is torn down for the winter. It is a dog below 7,000rpm. A different sprocket combo is on the to-do list (7,000rpm at 65mph makes for an unpleasant commute)

It currently has an aftermarket 4-1 that is completely unrestricted (3.14sq in cross-section).
IIRC, I have Keinhin 34mm carbs, that are jetted 2 sizes above stock, and oversized pods in place of the air box.

The numbers I listed are just the maximum lengths that I can fit without modifying the frame. I think I'll play around with the carb-engine runner lengths, and add some baffles to the exhaust. The stock exhaust was dual 2-1's, each with an exit diameter of 3/4" (.88sq in cross-section COMBINED)

If I ever fix my camera I'll post some photos.

__________________
$60 OM617 Blank Exhaust Flanges
$110 OM606 Blank Exhaust Flanges
No merc at the moment

You may need to rethink your riding style. You are riding a machine that reaches the sweet spot in its powerband at 9K RPM (you have a 14K redline, right?)

Low-end grunt is for v-twins and singles.

I rode a 2-stroke Yamaha RZ350 in AHRMA for three years, and you get used to the buzzing after a while.

Otherwise, I'd suggest a Yoshimura 4-into-1 pipe and a jet kit.

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1972 W115 220D/8 SLS, Coffman Starter "Ümläüt"

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(='.'=) This is Bunny. Copy and paste bunny into your
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not sure which 600 you have but the bore vs stroke numbers do not lend themselves to low end torque, they are designed for RPM. you cant really change the fundamental design of the motor.

Specifications-----Ninja ZX-6R-----Ninja ZX-6-------Ninja 600R
Displacement-------599 cc-----------599 cc-----------592 cc
Bore and stroke-----66 x 43.8 mm----64 x 46.6 mm-----70 x 52.4 mm

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1982 300CD Turbo (Otis, "ups & downs") parts for sale
2003 TJ with Hemi (to go anywhere, quickly) sold
2001 Excursion Powerstroke (to go dependably)
1970 Mustang 428SCJ (to go fast)
1962 Corvette LS1 (to go in style)
2001 Schwinn Grape Krate 10spd (if all else fails)

Have you ever run compression and cylinder leakdown tests on the engine? Just wondering if engine wear is a contributing factor to the lack of power below 7k.

the first thing you need to do is dyno the bike before you loose the base line

our race dyno has a time element on it meaning we plot the power cerv in real time during a pull

we only do pulls from a fixed RPM ( like 2500 ) to red line 10 11 thousand in one gear we use 4th and keep in mind. changes to the good ( torque ) is measured in speed of power ( torque ) not how much power does it top out at -

so i am saying do only 4th gear pulls and the CP can lay one over the other

Pro road race crews always look at torque and at the speed it makes the torque
rear wheel HP is only a number to sell the bike

find a shop that has a time element on their dyno and everything you do can be seen for sure did it work or not --

My shop won 3 USA National championships Road Racing one in 1998 and 2 in 2000 - jz