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I haven't seen anything predone that you can order. doesn't seem like it'd be too difficult to get done since the exhaust comes form the center of the front of the engine. It drops under and goes back and to the right. If you straighten it out and find a way to get it up between the wheel and suspension without killing the integrity of the bike's structure, you only would have to add a foot or so of pipe. You'd also have to find a way to get the exhaust to fit between the wheel and the seat.

Oh yeah, I've heard of concerns int he heat resistance of the plastic under the seat since it wasn't produced to withstand the heat of the exhaust.
 

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Primary pipe length for the CBR250R is 19 inches and secondary pipe length is 18 inches (exit point inside the silencer box), unless you are prepared to have a very long snake under the sump, then this is practically not possible
 

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I was just curious if anyone has tried anything like what is shown in the pic. I love my CBR250...but I cannot stand the exhaust design/placement.
There are a few small cans available (can't really call them mufflers considering how insanely loud they are), that only extend 6" or 8" beyond the end of the header pipe. While you're not alone in you're opinion of the appearance of the stock muffler, the majority of CBR250R owners who replace it with an aftermarket unit have done so with a proper sized slip-on that won't rattle the neighbor's windows.

If you look at the stickies at the top of the Performance forum, you'll find an extensive index of exhaust threads that covers virtually everything available in the aftermarket.
 

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You probably could rig up a small can in the under cowl. Wouldn't point out the side perfect, but if you really wanted to rig it up.

Not sure how accessible the oil drain bolt would be anymore though. And with the pipe being that much shorter and a tiny can, I could imagine how loud it would be. Loud enough to make people mad. ;)
 

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I replaced mine with a coffmans shorty exhaust it's only about 10 inches but insanely loud, most of my neighbors have noisiey dogs so if they complain I just say that. Plus I leave at 7 and get home around 3 so no one is usually home or just getting up around d that time.
 

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Primary pipe length for the CBR250R is 19 inches and secondary pipe length is 18 inches (exit point inside the silencer box), unless you are prepared to have a very long snake under the sump, then this is practically not possible
secondary pipe is actually longer than that because it goes back and forth an additional 2 times. But good call, your one of the people that actually get it ;)
 

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secondary pipe is actually longer than that because it goes back and forth an additional 2 times. But good call, your one of the people that actually get it ;)
The reflection / pressure wave that forms the tuned length is cause by a pipe end or change in section. The primary length from exhaust valve to mid pipe joint is 19 inches (pipe section change caused by the carbon gasket and slip on), the 'tail length' is to just past the foot rest hanger mounting bolt, (18 inches to the end of the pipe in the silencer box), the 2-3 passes in the silencer box are not helping in the tuned length.

exhaust pipes

BBDC 40°, 8500rpm, 249cc

The majority of slip-on's have a longer mid-pipe and silencer tube causing the secondary tuned length to increase the low end torque at the expense of high rpm power.

Nearly everyone who fits a slip-on comments on the slight increase of the bottom end but indicates you need a power commander to get the top end back as it feels lacking.

In my opinion the slip-on's need resigning to be more compact as not to alter the secondary tuned length.
 

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I once thought of modding that underbelly exhaust can from LeoVince than I imagined the amount of work put on it to make it perform well as stock:
-New pipe (if you want to keep the stock thing): 130$ (in my place probably cheaper but I will give the US price for better calculation)
-Custom-made chamber (it's the big box-like mid-pipe on big bikes like the CBR1000RR or CB1000R). Reason for having this thing is to keep a little back-pressure up AND the noise down. Trust me with the sound part, you don't want to hear it scream at 7-8k rpm everyday after work. Price will varies, if you have access to a CBR150R mid-chamber, go for it, it's small and compact and really does the job well on the 150cc machine.
Here it is, the black box before the exhaust can

-The LeoVince can: 500$. may have to add 50$ for labor retrofitting stuff to "hang" it under the bike.
-The fuel control unit: why, you may ask. It's because you've just changed the exhaust into a full system: 300$. You can calibrate the thing yourself but it's best to leave that to a professional. NOTE: this does not include dyno fee or labor time.
-This is optional (I think): new airfilter for the added thirst for air of the new system ~ 10-20$

The total is almost 1000$ solely for the look good effect on a 5000$ machine. I'm not trying to talk you out of this, I simply state my opinions. I welcome modders because they can do what I am too afraid to do. Hope you find this informative.
 
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