In the September issue of Dirt Wheels, they tested the Yoshimura slipon exhaust and only gained .4 hp! This was without the quiet core and with the open tip end cap and the sound level was 102db!! So, who in their right mind would pay $400 for only .4 hp and **** all their neighbors off? Usually, magazines inflate numbers so for them to only .4 hp, it must be somewhat accurate...is it?

 

I just saw that a few mins ago and couldn't believe the Yosh slip on only adds .4 hp. If i'm going to make my Z louder it better add some good hp. Where I ride I would rather have something that adds some hp but sounds somewhat to stock.

I have to agree with you about the noise factor Guido, I am wondering how the FMF with the quiet core will sound.

 

That test says it had the quietcore/spark arrester installed when they came up with the 30.2hp from the 29.8hp stock. When they took it off it went up to 31.2. Wow!!! 1.4hp for only $399. Hook me up.

 

Opps, I didn't read the whole article. Well thats a little more like it.

 

Ya,
I've been thinking the same thing. There is no way I'm going to spend a bunch of money for 1HP and end up with an obnoxiously loud quad I cant ride on the DNR trails.
Why can't they just make a rebuildable glass pack type straight through muffler for quads?
It would have zero backpressure and with a fresh repack, would be about the same DB's as the stock setup.
That I could live with.

 

I wonder if you have to fix a few things before you can see real changes in power. Like the carb. I was told that putting the stock 400ex carb on the Z really helped a lot.

MX

 

<< I wonder if you have to fix a few things before you can see real changes in power. Like the carb. I was told that putting the stock 400ex carb on the Z really helped a lot. >>



What's the difference between the two &amp; what makes the Z400 carb inferior?

 

I purchased the full Yoshi system and am completely satisfied with the HUGE power increase over stock. It FEELS more like 10 ponies over stock. It hits the rev limiter too fast in first and second but that will be fixed soon. One tooth larger in front and yoshi's rev box. This motor really needs to breathe and with the pipe you will get killer bottom and mid gains. It's no CRF450r motor but for a 400cc its radical and way worth the $440 for the full system!

 

This is what I have been told. The carb on the Z400 is pretty small and low tech. The ideal is the FCR but, a 400ex carb is a big improvement.

 

Rodsquad- got the crf up and running???????? The new and improved 686 raptor completed the breakin on monday. She is ready for action. She is a runner. I do not think she can pass Randy's DS760, but i do not think he will be far ahead.


Did you ever get those pink riding pants?

Nothing is worse than a ex raptor owner!!!!!! Got the new axle on the Z?