Exaust

I can get hold of a standard wr 450 pipe is it worth fitting to the klx ? Is there any gains to be had ? It won't cost me nothin bar a bit of stuffing about fitting it . my bike is a stock klx400 r what do you blokes reackon ?

It has to at Least save some weight

I can get hold of a standard wr 450 pipe is it worth fitting to the klx ? Is there any gains to be had ? It won't cost me nothin bar a bit of stuffing about fitting it . my bike is a stock klx400 r what do you blokes reackon ?

Are you talking about just the muffler or complete pipe?

Either way I would suggest you're wasting your time for fark all gain.

So yes do it but first do a dyno run with the OEM pipe, then an after run with the Yamaha pipe and post your results.

Try it and let us know how it turns out.  Depending on the year the WR pipe is either steel (not so light) or aluminum.  Either one will have baffles, not packing.  I think it will flow better then the DRZ pipe and still not be crazy loud.

It's off an 08 think alluminium pipe and just the muffler.

keep us informed please. i would like to do the same to my drz. my modified exhaust is too loud and heavy. wr mufflers seem like the best choice. i'm sure yamaha knew what they were doing when they designed there mufflers and always factory mufflers flow the best relative to sound level

The RMZ 450 oem muffler I fitted to my S (with below mods inc E model bigger header)flowed that much better over the E muffler I had to go from a 160mj to a 175mj on the DXP needle, the bark is a bitt much under load on the road but the performance gains were very noticeable, only cost me 80 buck for the whole shebang, refer to my user photo for how it looks.

The RMZ 450 oem muffler I fitted to my S (with below mods inc E model bigger header)flowed that much better over the E muffler I had to go from a 160mj to a 175mj on the DXP needle, the bark is a bitt much under load on the road but the performance gains were very noticeable, only cost me 80 buck for the whole shebang, refer to my user photo for how it looks.

 that looks great drzkiwi. did you notice any loss of torque going to the E header. i have the sm and was thinking to use the  bigger header but out right power is not my main need. i need low down torque. any body know of any dyno charts to show the effect of the bigger header on the sm or s models

The bike makes the same power at half throttle as it did full throttle right the way through, then when the std setup signed off this combo just continues for at least another 2500 rpm at a guess, however it was the combination of cams, compression, mild head work, exhaust and FCR carb that made the difference, one supports the other, synergy, but the header on the S or SM models is too small, an EARLY E model header is a good place to start (41 or 42 mm as opposed to 38mm), almost more important than the muffler, the latter you can relieve with a long drill bit, the muffler was off 2005 model RMZ 450, the bolt holes line up perfectly with my S mounting points, I cut 10 inches off the original muffler and grafted this into the shortened inlet on the RMZ muffler, one is a tight fit in the other, just weld the joint with a TIG, bolt up and go, however it has some bark, but at least people don't pull out in front of me and get out of my road, they hear me coming so I'm safer on the road, AND ITS BRIGHT YELLOW.

Got the wr exaust today let the fun begin !ImageUploadedByThumper Talk1381803240.516294.jpg

I modified the outlet on the RMZ muffler from 35mm to 43mm, made a massive difference power wise (before the bike seized) and it was quieter, not so raspy and deeper, check the outlet pipe is not too small, may be a source of restriction, at least balance the size between the muffler core and the outlet,cheers

Did a mock up of the pipe set up just have to sort out a joiner pipe and its a goer defiantly looks the part !ImageUploadedByThumper Talk1385459898.504271.jpgImageUploadedByThumper Talk1385459950.433520.jpg

Yeah but where's the fun in geting someone else to do it for you . Figuring it out is half the fun

Kawazuki , have you thought of moving the muffler mount ? An exhaust shop probably couldnt weld alloy , but a decent welding shop could , then you wouldnt have to make up a finiky joiner . Also I am not up on kawa/suzy models , does yours have the larger header pipe ? This could be a good opportunity to get rid of the old bottleneck if it hasnt , greg

Kawazuki , have you thought of moving the muffler mount ? An exhaust shop probably couldnt weld alloy , but a decent welding shop could , then you wouldnt have to make up a finiky joiner . Also I am not up on kawa/suzy models , does yours have the larger header pipe ? This could be a good opportunity to get rid of the old bottleneck if it hasnt , greg

Yeah mate is a real "E" as you blokes would call it has all the good stuff strait from the factory . No good moving the mount the wr exhaust bends at all the wrong angles to mate up with the header making a custom joiner is the only way . The wr pipe is 38mm I.D and the klx header is 41 O.D so a reducer is needed any way . Good excuse to spend some quality time in the shed I reckon

Yeah but where's the fun in geting someone else to do it for you . Figuring it out is half the fun

 

Most people don't have a pipe expander or bender... :p

Most people don't have a pipe expander or bender... :p

yeah me neither I'm using pipe I found the right diameter and cutting wedges out and welding them back together to get the bend where I want it ImageUploadedByThumper Talk1385950882.004688.jpg

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