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2006 crf-250r

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Posted by: geraldo---------------------

So they are coming from the factory with the dual-exhaust. Is this for actual increased performance or is it just aftermarket support? I would be interested in hearing about a first hand ride.
http://powersports.honda.com/motorc...odelId=CRF250R6


Posted by: bigred455---------------------

It is for the AMA,(put it to the consumer,RIDERS) so they can mandate another rule for the factories and manufacturers,Just like with 2 strokes .Also the aftermarket companies have job security. Did you(not personally)think it was going to end when 4 strokes became mainstream in MX.


Posted by: Rich Rohrich---------------------

They are using two mufflers to get enough canister volume to meet the new sound level requirements without taking a huge hit on horsepower. Silencing while retaining good power power is very much releated to the volume of the absorption material and two cans is a logical way to package that additional volume.


Posted by: geraldo---------------------

I believe that this design does work. I had a honda nx650 which had dual mufflers and it was very quiet. I don't actually know what it did performance wise for the bike because it didn't have that much.


Posted by: holeshot---------------------

A rider I raced moto with several years ago had a 610 four stroke single Husky with dual exhaust (about 95ish model year). He got a lot of holeshots on that thing, even though he was as big as two or three average people. But then again, the bike was big (577 actual cc, I think).

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Posted by: bedell99---------------------

You really think it affects the CG of the bike with a dual exhaust. The bike is so narrow already. Its all about marketing and in the past Honda has done a real good job with it. i would of believed sound over handling.


Erik


Posted by: john3_16---------------------

Yeah....I really doubt handling was the purpose for doing the dual exhaust...They do say that (marketing) but what does that change effect most ? Lowering sound without restricting power...It would have very little effect on handling if any...

The sportbike crowd knows this as well...The dual exhaust on the RC51 didn't help handling one bit..That's why the race team ran a single unit for AMA superbike...The average guy could get more lowend with the dual unit but for those that wanted better handling and lighter weight an aftermarket 2 into 1 did the trick but the lower mid suffered a bit of a power dip on the dyno graphs. Plus, it was one of the LOUDEST aftermarket exhaust to be had.

The factory race teams had the resources to get the best of both worlds...Lighter weight from the single exhaust without much loss to the midrange because of their access to engine mods on a Vtwin that had nothing in common with the stock RC51.


Posted by: Chili---------------------

One of the 06's was raced here this past weekend. My uncalibrated ear testing tells me it doesn't seem any quieter than the 05. Word was it was quieter at the testing RPM but just as loud under power?


Posted by: syko---------------------

it's been reduced 2 decibels.
from 98 to 96.
generally this is almost untracable to the human ear so as spectators/racers we aren't gonna hear any difference.
However an actual reduction of 2 decibals can make a decent impact on power output of a bike so the twin pipe design, in honda's eyes, was worth the effort to increase power 'slightly' over the 05 and still keep it in line with various governing bodies ever changing sound restrictions.

as for handling, As far as I am aware this was not in anyway Honda's motivation for the design and did infact ditch an early twin pipe design because it was having a negative effect on handling. basically it's been done to reduce decibels whilst maintaining power and handling properties found in the 05 bike.

I tried an 06 this past sunday. it still handles great, it still has a nice smooth power output and doesn't sound any different.


Posted by: oldguy---------------------

Quote:
Originally Posted by Chili
One of the 06's was raced here this past weekend. My uncalibrated ear testing tells me it doesn't seem any quieter than the 05. Word was it was quieter at the testing RPM but just as loud under power?

I second this Chili. A good friend raced his this last weekend and when he and eric were riding to the start there was no noticable difference to my ear. On the track the honda might have been slightly quieter but not that I would swear to



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