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Discussion Starter · #1 ·
Ok guys and gals, here is something that is bothering me and I need to fix it. Who has owned a 600rr loves the center up exhaust, and I am wondering if any of you have encountered someone who can fabricate such an exhaust for the 300r. Yes obviously the mudflap crap in the rear will need to bleed and be removed, but with license plate mounting aside, I believe it may very well be the sexiest modification to the 300R.


Any suggestions? Or do I need to get the mandrel out and bend me an exhaust?
 

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give the older 250r forums a look the bikes are almost the same. You might find your answer there. The 300 is still a little new in most areas so not a lot of people have done much with them besides basic bolt ons and such
 

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Ok guys and gals, here is something that is bothering me and I need to fix it. Who has owned a 600rr loves the center up exhaust, and I am wondering if any of you have encountered someone who can fabricate such an exhaust for the 300r. Yes obviously the mudflap crap in the rear will need to bleed and be removed, but with license plate mounting aside, I believe it may very well be the sexiest modification to the 300R.


Any suggestions? Or do I need to get the mandrel out and bend me an exhaust?

This question of the feasibility of a under tail exhaust has come up numerous times on CBR250.net.

If you've got a lot of time, money, & fabrication equipment, anything is possible. But it would take a whole lot more than just buying some tubing and bending it... take a close look at a CBR600RR, and you'll see that not only the tail/seat section is designed for clearance around the muffler, but that the swing arm is also designed with a cut away section to allow clearance for the mid-pipe. None of this was done as an afterthought on the 600RR, it was integrated as part of the original design of the bike.

Honestly, it would probably be more cost effective to just go out and buy a new 600RR than it would be to buy a 300R and then spend the time & money necessary to fabricate everything needed to create an under tail exhaust.
 
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Discussion Starter · #4 ·
MotoMike, you may be correct to an extent, but I believe that aside from the price of the muffler, this can be had for about $340-380. The issue at this point would only be clearance, and at that point with the rear shock removed completley and the swing arm collapsed to the max, a quality fabricator should be able to create the same piping from the location of the original up under the seat. Or my goal is to have a connection point with a gasket where as I may remove the motor without removing much else from under tail. I may seem crazy, but trust me, this can be done. We've created a bit more tighter spec jobs before, and this is no different. As I heard a wise man once say, its only impossible when you quit.
 

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Would likely require too much surgery and would play with the factory engineering. As @MotoMike mentioned, better to go out and buy a 600RR instead (not only for the sake of cost savings).

Bright side of the side exhaust: Won't heat up the passenger's a$$, and plus the side exhaust may be better performance-wise for the bike, from what I've read.

Honda designed this bike the way it is for a reason, and I wouldn't want to eff up their finishing touch. To each his own. :)
 

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An interesting idea/concept Vlad, not one I had thought of. I do a fair amount of metal fabrication in my daily work so was naturally curious how much of a mission it would be.
Where were you thinking of bringing the pipe through/up?
Looking at the bike there is a 38mm gap between the right hand side of the rear spring coil and the side of the swingarm. This is a snug fit for a pipe of the same diameter as the header pipe but leaves no room for clearance. Cant see where else it could go tho.
 

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Discussion Starter · #7 ·
kiwi rider, have you ever seen a rectangular pipe?

Yes, not you may picture my idea. With a rectangular pipe whos bottleneck is the same volume of the original diameter, a tight clearance such as the 38mm you speak of can be achieved even with some thermal tape to protect the integrity of the farings, or some aluminum backing for the afore mentioned purpose. Yes i know this all seems crazy, but my main concern is not the heat in the rear seat as it will be replaced with a carbon crowl, but the balance that is achieved and the aerodynamic advantage that a streamlined bike has. It's about more than the power or speed, winning in all sports is about balance.

I believe that a proper center up exhaust will give the bike better aerodynamics, more power, better flickability, and a better riding experience by not having a bloody exhaust be in the way.

All in all, it is better to try and fail, than to have never tried at all.
 

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... I believe that a proper center up exhaust will give the bike better aerodynamics, more power, better flickability, and a better riding experience by not having a bloody exhaust be in the way.
I don't think those items are huge concerns for these bikes. It's not a case of possibly scraping the muffler in a corner, as you would be well into a low side slide long before the muffler would make contact with the road. I really doubt you'd see more power... the "low pipe" routing of the stock exhaust (as well as any of the aftermarket slip-on's) is about as efficient and free flowing design as it gets for a single cylinder bike. For example, this FMF Apex slip-on...

DSC_0076.JPG

I can't see how a heavier (no denying, it has to be heavier) under tail exhaust, with all the additional tight pipe bends and length, could possibly be more efficient power wise than what you'd have with something like the FMF unit as shown above. Also, that FMF Carbon Fiber slip-on weighs less than 4 lbs.

As for better "flickability", that is really a function of the quality of the tires, as well as rider skill.


All in all, it is better to try and fail, than to have never tried at all.
It's your bike (or should I say, it will be your bike once you buy it)... go for it. You would be the very first to fabricate such an exhaust system for these bikes.
 

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Flickability is something aided by a low center of gravity, I think if anything a center up exhaust would have an opposite affect... but not a huge one.
 

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Interesting to note that the new Interceptor has gone from the under tail version (2009), to the plain looking can on the right side (much like ours). I can't help but wonder what they were doing this time around. I like the look of the undertail exhaust better, but no doubt it was much heavier than the one on the current version.
 

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While an under tail exhaust design has its fans due to visual appeal, it is interesting that there are not very many bikes incorporating the design... the current Honda CBR600RR is among the few. From what I've seen, far more models of sport bikes have either conventional low mounted exhausts, or the more recent design trend of the main body of the muffler being tucked under the engine, with the exhaust outlet just behind the right side foot peg.
 
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