I've decided to spend my KLX $$$ on suspension. I'm willing to perform the cheap/free mods for power cause every little bit helps.

My question is - does modding the stock exhaust add anything in the way of power? Or is it just to change the sound of the puny stock exhaust? By mods I mean simply drilling a 1/2" hole in the last baffle and maybe a 3/8" hole in the second to last.

I've seen a lot of people allude to this mod but never a difinitive answer as to whether it's worthwhile or not.

People who have done it - did you keep it or move on to an aftermarket can?

BTW, how much louder is the stock can once it's been modified? I guess if it's a lot louder AND doesn't add anything, then I'll probably drop it from my "to do" list.

 

It seems like a lot of folks drilled through years ago, but not so many recently. The spark arrestor WILL be ruined if you drill through.

 

Why waste your money on suspension. Unless you do serious off road in which case you bought the wrong bike. Seriously the bike needs un-corked (Curse the EPA) more than it needs suspension. You will more than likely not see any gains until you rejet and do a slip on. Best of luck whatever you choose to do.

 

Do not drill the exhaust. All you will be doing is ruining the spark arrester and won't gain anything. What you need to do is replace the end cap.


09 KLX250S Custom Exhaust Sound - Kawasaki D-Tracker - YouTube

https://www.kawasakiforums.com/forum...inished-35018/

 

IDRDR - I definitely want the SA.

2veedubs - I'm uncorking with the free/cheap mods including jetting. But that level of power is perfect for the serious offroading that I do. Any more power would be necessary for street only. More power does not equal better offroad. Suspension does. I plan on trying appropriate springs first and then revalving if necessary.

Wildcard - that sounds great...but did it add anything to the power? Also, is there welding involved with the end cap change? Unfortunately, I don't weld.

 

I agree with your approach. I uncorked and re-sprung at about the same time. Then added valves in the forks. I learned a lot about suspension in the process, with one thing being I probably did not get heavy enough springs as TNC was discussing recently. I load this thing up, and the Race Tech recommendations for the KLX300, a lighter bike, were probably not adequate. I also underestimated how much time I would spend on the trail with camping gear.

 

Personally I think a new slip-on is worth it. I noticed a little boost in power and like the sound much better. IMO, not much louder then the stock muffler.

 

...that sounds very similar to a fmf q4...good job..

 

Your suspension must still be as delivered.

"Bill Blue 331, Q4, P-Bomb. "

Are you sure you bought the right bike? There must have been a reason you wasted money on these modifications^^ If your suspension was left alone, your bike still handles poorly.

It's more fun to ride a slow (read: underpowered) bike fast than it is to ride a fast(er) bike, slow.

 

Hey Scott, I didn't find a cheaper source for the 6.3 Eibach rear spring, but I was able to locate a 6.4 Race Tech spring which is on its way...I get parts through my old shop where I used to work at cost. I pulled everything down yesterday. The fact that the 300 spring is 15mm longer than our '06/'07 spring requires you to keep an eye on the clearance between the airbox boot clamp and the shock spring collar nuts. My soft, OEM airboot clamp was eaten through fairly quickly with no contact to the soft rubber boot. I replaced the OEM clamp with a stainless steel version, and all the wear it shows at this time after much use is some chaffing. Still, the ultimate solution is to insure the airbox is pushed over away from the shock as far as possible. I'm even going to open up the bolt holes a tiny bit for insurance against any future contact. Just something to consider.

On the issue of suspension over increased power, it's always debatable and how you use the bike will determine which is best. Frankly I want both, but I really use my KLX in some fairly gnarly conditions. Having 50 hp would have done me no good with the OEM suspension damping IMO. It sucked.