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Why is my 200 so LOUD !?!?! I have done the airbox mod and have a Bill's Pipe installed. I am working on Jetting it right, the guy I got it never did that and it is really rich right now, but that shouldn't have any effect on the noise level does it?

It is not too bad with the stock silencer on the bike, but it is still loud. I have tried the Pro circuit SA and the FMF Turbinecore 2 and they are both LOUD. With the aftermarket mufflers, it is louder than the neighbors CR250 with the Turbinecore 2 and it is louder that my other friends XR650R with the White Brothers. My old husqvarna 430 isn't nearly this loud either.

I always thought the 250 was loud, but it doesn't hold a candle to my 200 with aftermarket muffler.

What can I do? Can I wrap the pipe with header tape? What about these: http://www.thedbsnorkel.com/ Would this help a lot? Anybody got one?

Can anybody save my ears?

That snorkel kills the KDX's power output. Put a pipe guard on it... it helps... but the KDX is a quiet bike compared to others normally. Bill's pipe is probably thin metal....

Are you talking about the exhaust note...or noise from the pipe?

This:
'it doesn't hold a candle to my 200 with aftermarket muffler.'

..sounds like exhaust is the question.

This:
'Can I wrap the pipe with header tape?'

..sounds like the pipe is the question.

Pipe wrap will certainly quiet the pipe..and add a good amount of weight.

'Loud' being a matter of who's listening...do you have access to a db meter? A well packed silencer with an FmF pipe can get you 88db at the exhaust. More likely to be 92 or so.

Also could be an exhaust leak at the cylinder...

Indawoods wrote:Also could be an exhaust leak at the cylinder...

That's a good possibility. I had that happen on mine. I used some permatex and it went away.

I am pretty sure it is the exhaust noise.

I guess that I will look into a leak at the cylinder. As good a place to start as any. Thanks. Particular type of Permatex that you used? Do you just make a gasket and seal up the pipe where it connects to the motor?

Inda - do you have experience with the snorkel?

I do have a Pipe Guard, nothing special. It is one of the Universal metal ones that you bend around the pipe and hold on with clamps.

My neighbor with the CR has commented in the past that he can hear the 200 start up when he is at his place and I am at mine. That is almost a mile away.

I will go home and play with it a little more.

We had a member try it out and it killed all the power the KDX has... not worth the effort or money from his report.

http://www.kdxrider.net/forums/viewtopi ... ht=snorkel

This doesn't make sense. Did you buy the silencer used? If so, does it need to be repacked?

I have an FMF pipe and Powercore II on mine and it is still the quiest bike in my riding group - minis included. I can hear riders coming up behind me form a long ways back.

First thing I thought was PACKING. Need to repack my RM, on my last enduro I clocked in at 95 DECIBELS.

I played with it a little bit last night. I have taken the pipe off before but this is the first time that a spacer fell out. Didn't see it up in there before, hope it is not needed. I put it all back together without the spacer and it sealed up a little better. Cut the noise a little. There are no o-rings on the Bills pipe where it meets the motor, so I am thinking that making one with permatex maybe a good idea based on your comments. There is a place on the pipe where it would be easy to do.

I don't have any packing material on hand. Shop opens up today, I can stop by on the way home. New packing didn't make a lot of difference on my old Husky, so it is not something that I think of.

About the header tape comment, I have heard about it used to cool the headers in cars (to protect wires and such), and it also quited the motor down a little. This is where I got the idea about wrapping the pipe.

but this is the first time that a spacer fell out. Didn't see it up in there before, hope it is not needed. I put it all back together without the spacer and it sealed up a little better

You need that spacer to make a proper seal and not t fubar your cylinder because of the vibration with the pipe. Sounds like you didn't line up the pipe and cylinder properly before. Try it again with the copper ring. I also use some high temp silicone around the head pipe to make a really good seal (don't need a lot, just a small bead around the pipe, let it DRY before you put it on and fire it up, you don't want any silicone in your engine)

goood luck

This is one choice:



Clean the exhaust port. Put that copper gasket back in. Clean the pipe joint. Put a bead around the pipe just back from the end. Bolt it up. CURE the RTV before you start the bike (already said). Hang a trouble light (uh..incandescent bulb) under the joint overnight.

Don't fiddle with pipe fit for ten minutes after you make the pipe/cylinder joint. That will compromise the seal. Make sure the pipe fits BEFORE you put the RTV on.

The 'noise' from a leaking exhaust is not at all the same as the 'noise' from either a thin pipe OR a silencer that is need of packing.

Ever see any exhaust smoke anyplace but the exhaust tip?

No o-rings on the pipe? That's bogus.

What's your assembly procedure? IF your place the pipe in the cylinder, attach the springs, then the mounts...does the spark arrestor line up perfectly...or you do put the SA on the pipe stinger, then lever it to line up with the SA mounts?

IF the latter..that pipe likely never has sealed.

Sounds like you might have a torque ring (spacer) added in the e-port, which is not necessary. What is necessary is the crush washer that shecka mentioned.

Sorry, I haven't updated this thread in a while. I got busy at work and didn't get back to it here.

I ordered parts over 3 weeks ago and am still waiting for them to arrive. I pulled the exhaust off of the bike and cleaned up the motor and got to looking. I don't have the gasket and my local bike shop is having trouble getting it in. I don't know why, but the one shop is the only option that I have to get Kawi parts. They are not a dealer, just a general bike shop. The only other shop will only touch Yamaha's, they won't even order parts unless it is for a Yamaha. I try to support my local shops when I can, but I got sick of waiting and just went to Bikebandit and ordered it. Should be here this week. Haven't really had any time to work on the bike anyway.

I did go ahead and put some silicon around the pipe in the groves at the end of it like you suggested and that did help some. It seals better there now. Yes, there are no o-rings on my pipe, but I don't know if that is normal or not. If there are supposed to be o-rings in those groves, then they would be some of the thickest o-rings that I have ever seen.

I always mount the expansion chamber first. Loosen up the mounts so I can move them. Line up the pipe and bolt it on. Hook up the springs. Then I line up the silencer to the pipe and bolt it on. Is this wrong? It is how I have always done it.

I am hoping that when I get the gasket in there that it will seal a lot better and get the noise down to a reasonable level. If this doesn't fix it, then the shop has packing in stock.

Re: 'Yes, there are no o-rings on my pipe, but I don't know if that is normal or not. If there are supposed to be o-rings in those groves, then they would be some of the thickest o-rings that I have ever seen.'

There are supposed to be o-rings in those grooves...that is how the pipe seals to the cylinder.

Although...they don't usually work that great, thus the silicon idea. I wouldn't say the rings are necessary-or-die, but my choice is to use them, seal or not, as a cushion between steel (pipe) and aluminum (cylinder).

THAT said having never seen a Bill's pipe on a KDX. I could not say they are NOT different. Still...having a sealed exhaust system in a 2-stroke is very important to engine tune and performance. Any leaks will compromise. IF the Bill's pipe does not HAVE o-rings that is rather stupid.


Re: '.. Line up the pipe and bolt it on. Hook up the springs..'

That's a good way to have a leak.

Put the springs on first...THEN tighten the mounts, watching for inordinate headpipe movement. It's not having the mounts 'right' that determine if the pipe fits...it's having the headpipe seated in the exhaust port...which isn't going to happen if it can't move...which it can't if the bolts are tight (or sometimes even if just hooked up!).

I suppose others have a different sequence of doing it. We know they are simply wrong.


It is conceivable, having maybe a tweaked pipe, that the head/cylinder joint is completely goobered if the mounts are lined up. Conversely, if the pipe is seated in the cylinder, the mounts may well be impossible to bolt up.

It doesn't take that much of a hit to tweak a pipe, either.

Good luck!

Look below... Let Bandit bring you your parts! They have them and send them fast!

I have played with it a couple of times now. The muffler packing looked good so I didn't bother to replace it. I have tried putting the air box lid on and off. Changed out the stock for aftermarket muffler and back. I put on new springs and got the copper gasket to seal up the pipe at the motor. Siliconed it too.

I think that Inda hit it on the head when he said the metal on the Bill's pipe is just thin.

Thanks for all of the suggestions and tips.

september9 wrote: About the header tape comment, I have heard about it used to cool the headers in cars (to protect wires and such), and it also quited the motor down a little. This is where I got the idea about wrapping the pipe.

Wrong! The exhaust wrap keeps the heat inside the exhaust to negligably increase exhaust scavenging. It pretty much holds moisture against your exhaust in order to help accelerate the rusting.

Don't do it if you care about your bike.


The permatex is the chit for exhaust sealing, EVERYONE on the CR500 websites uses it instead of the exhaust gaskets because it is more durable. Use the red high temp silicone.