Hey guys. Here is the situation. I am running 13/41 sprockets. My carb is rejetted to a 138. I started out running 10 discs in my supertrapp IDS2 quiet series exhaust. I am now down to 4 discs and the problem has not gone away. Here is what it is doing. 1st, 2nd, and 3rd gear scream without one bit of hesitation. the last 5% of 4th gear you begin to notice that something isn't quite right. You shift into 5th and (bear in mind you have the throttle wide open!) when it reaches about 70% of the range of 5th it bogs down completly. The only way to make it stop bogging is to totally get off the gas and downshift into 4th.

What do you think? Is it running too rich, too lean, starving for air? Don't know about the starving for air part because I totally removed the air filter for one run down the road...still did it.

The plug. That's another story. At ten discs the sparkplug was totally clean, as in nothing...(I know that's not good...is it?) At 4 discs I am showing alittle slight tinge of blackening on the plug. Just to confuse you even more at 6 and 8 discs I showed alittle graying of the plug.

Help me guys because 5th gear at this point is useless.

Thanks in advance,

 

a friend of mine has a 2000 mojave, its all stock, when he is in 5th and starting to wind it out, it starts breaking up, He has only had it a week and it has been dooing this from day 1. as well as he already busted 1 front shock, not even on a big jump. whats up with this, whats up with kawasaki?

ride hard, ride red
86 ATC250r Fast
91 250(soon 2 b 350)X

 

Must of been one hell of a landing. I've owned two mojave's and never broken anything. And I did some scary things on them. Are you sure it's not the rev limiter kicking in?

 

That is a good point. You may want to check with Kawasaki or a local dealer regarding a rev limiter on your bike. I have an '87 Mojave and since a rebuild top end in 5th sputters a tad. Not enough to bother me, but nonetheless.

You did however make a common mistake. Never change numerous things at once! This only leads to confusion as to why "things aren't right".

The gearing shouldn't have too much to do with your problem, however how does the bike run with stock jetting and the new muffler?

Try returning the bike to stock and install one component at a time, starting with the muffler, then gear, THEN jetting.

Regarding the plug, it should be slightly soiled, not white nor grey, and not sooty black.

Hope that going back to basics will help you. Let us know how it goes.

 

I just pulled this from Supertrapp's website, this should help you understand how that muffler works exactly...


The SuperTrapp uses a patented radial diffuser system. A series of discs with a precise gap form an exhaust outlet. By adding or subtracting discs, you can virtually wave tune your engine and carburetion.

You can increase or decrease the exhaust outlet size; adding discs opens the system and removing them reduces it.

The fewer the discs, the quieter the system; the more discs, the nosier it becomes.

SuperTrapp dispenses exhaust gases radially rather than straight out, it is greatly effective in reducing noise levels.

This opening and closing of the exhaust exit is very important to tuning. Allowing you to adjust your powerband, according to the type of track you are running.

Remove discs to decrease the exhaust opening and increase back pressure.

-This decreases the powerband to give you more low-end torque.

-Decreases the exhaust tone.

-Enriches the carburetion.

Add discs to increase the exhaust opening and reduce back pressure.

-This increases the powerband to give you more top-end.

-Increases the exhaust tone.

-Leans out the carburetion.


GOOD LUCK!

 

I had the same problem I thought it was the spark plug then I found out that It is the rev-limiter on the mojave thats why it keeps on beaking up.

 

Hey MXracer98,

Was it a defective rev limiter? The reason I ask is because I get more rev's out of the bike in 1st, 2nd, 3rd, and 4th. And when it happens to me in 5th gear just letting off the gas will not make it stop. You let off the gas and let it slow down to around the middle range of 5th gear and give it gas and it stills bogs. The only way to make it stop is to totally get off the gas, downshift into 4th and then give it some gas.

Was this some of the same problem?

Thanks,

 

In high 5th the rev limiter will kick in and make the engine break up and if you let off the gas a little if will break up still but the rev limiter just stops you from going to high in rpm's and floating the valves and seizing the engine you could get a klr250 rev limiter and be able to rev your engine higher before it kicks in. It has nothing to do with the pipe and except it makes you engine rev higher and it is not a defective rev limiter it is just doing it's job.