Why is my 2011 EC300 so snappy?

[Ryderod]

Howdy, I have an 07/08 (not sure) EC300, love the bike, very smooth power and great traction in tech stuff, the only non standard item on the bike is the rear canister. The original straight shaped tailpiece fell apart and I got hold of the old type banana shape pipe for a good price.
Sprocket combination is 13/52.

I have recently added a 2011 EC300 to my stable, this is running the stock FMF canister.
Sprocket combination is 13/50.

The power delivery on this 2011 bike seems a lot more aggressive, the bike feels snappier, almost like my old YZ, with the rear spinning out easier, and the front lifting easier than my older Gasser.

I would have though that the longer gearing would have smoothed out the 2011. I also notice that the mapping seems to make more of a difference on the older bike, with there being nearly a stutter or bog when revving up set in tech mode, which works quite effectively. The mapping on the 2011 seems to have virtually no noticeable effect no matter where it is set.

Is there a difference in flywheel weights between the two models, and could that banana pipe be responsible for the bulk of the difference? Any other areas I should look at?

I would like to try get the 2011 as smooth as the older bike..

[Jakobi]

Port casting
Port timing
Head setup (compression and squish clearance)
Suspension setup
Powervalve tension (shims and spring tension on the governor)

Quite a few things that could be causing the variance. Even between my 2010 and 2013 250s, both have been setup similiarly both in terms of chasis and engine. Both share a 38mm AS2 (although minor variance between them). They both jet differently and run as such, but I believe most will be due to changes in porting from year to year.

You won't really know whats what unless if you go about comparing and possibly swapping parts between bikes to identify the source. My guess would be that is a combination of the above.

[wence]

Fly wheel weight also?

[Ryderod]

Thanks for the replies. So it looks like the pipe wouldn't be such a factor. I will compare the head set up, PV tension, and flywheels to see if there are any distinct differences.

[pscook]

Jetting. Jetting. Jetting.

Pull down both carbs and compare what's inside. I would bet that jets, needles, slides, maybe even the carbs themselves are different. Could be a 38mm ASI on the older bike, and a 36mm ASII on the newer one.

My bet is jetting. Maybe the pipe, but more likely jetting. Your comment that the map switch is more effective on the older bike leads me to believe that jetting is the key here, as numerous owners state that the map switch is only truly effective on bikes with well sorted jetting.

Grab a screwdriver and get to work!

[Jakobi]

Agree. I thought I added that to my list but didn't, but as per my post even with 2 very similar engines running 38mm AS2 carbs there are noticable differences between them when running the same jetting and what they require jetting wise.

To the op, swapping the entire carb from one bike to the other would be a crude test. Be aware if the new bike does have an AS2 (shallow bowl carb), that it will require different setup to the older carb. If the 2011 is still running the stock jetting it will probably have the needle in a high clip pos and the snappy power or hit will be from the rich to lean transition in the off idle to midrange area.