Author Topic: Exhaust Alternatives for 300 sef  (Read 1110 times)

jamracing

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Exhaust Alternatives for 300 sef
« on: January 14, 2021, 06:06:46 PM »
Hey all - is it worth replacing the header/muffler on the 300? Anyone have dyno numbers to show the bigger headers like the fmf powerbomb?


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« Last Edit: January 15, 2021, 05:33:50 AM by jamracing »
2020 300 SE Factory

jamracing

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Re: Exhaust Alternatives for 300 sef
« Reply #1 on: January 23, 2021, 06:59:39 PM »
Wow, no responses! I guess the bike is perfect


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2020 300 SE Factory

DEL107

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Re: Exhaust Alternatives for 300 sef
« Reply #2 on: January 26, 2021, 09:28:25 AM »
Wow, no responses! I guess the bike is perfect


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LOL it's not KTM talk that's for sure.

I only remember watching a YouTube video while I was trying to decide what bike to buy. They said the Akrapovic that came on the factory model was worth 5 HP. Akra has always made good if not some of the best pipes for years so If you're gonna upgrade it's a safe choice.

You'll get more power with an FMF just because it's a straight thru muffler. As shipped they are too loud for off road, but decent if you get the quieter spark arrestor insert. The other open spark arrestor insert does nothing to tone it down
« Last Edit: January 26, 2021, 09:31:21 AM by DEL107 »

jamracing

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Re: Exhaust Alternatives for 300 sef
« Reply #3 on: January 26, 2021, 10:21:00 AM »
Tnx for the insight. I thought the limiting factor was the smaller diameter header, not the muffler. Can a non-Akro header be mated to the stock muffler? I don't want a loud bike, that's for sure
2020 300 SE Factory

eagle

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Re: Exhaust Alternatives for 300 sef
« Reply #4 on: January 26, 2021, 01:27:15 PM »
There was a write up about the fresco exhaust in 2017, & Jam you made the comment, that's a piece of art ! The fresco are a fair bit cheaper that the Akro also, which is a bonus !
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DEL107

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Re: Exhaust Alternatives for 300 sef
« Reply #5 on: January 26, 2021, 01:34:37 PM »
Tnx for the insight. I thought the limiting factor was the smaller diameter header, not the muffler. Can a non-Akro header be mated to the stock muffler? I don't want a loud bike, that's for sure

I don't know. for some reason FMF usually says there headers don't work with stock muffler but not vice versa. Usually it'll say something in the description if you dig around.

I just came off a steady diet of KTMs which actually have pretty good exhausts stock.  My last, a 350 SXF came to me with the 4.1 RCT can and it woke the dead, the long 94 d insert made it reasonable in the woods at part throttle. I asked people I rode with and they had no complaints. Still made some noise at full throttle. As soon as I put the insert in, I could feel it trimmed the top end a bit but that was never felt except ripping across a field. I think it reduced the outlet by 1/4 of an inch.

If your header is on the small size it's probably helping the grunt. If swapped out you'd probably feel that it revs more freely, but there could be a minor loss down low. Beyond it just being fun to buy parts, it might be a good choice if you are riding faster stuff.

There, we just increased the post count around here by 50% haha

Rick

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Re: Exhaust Alternatives for 300 sef
« Reply #6 on: January 26, 2021, 08:55:20 PM »
Hey all - is it worth replacing the header/muffler on the 300? Anyone have dyno numbers to show the bigger headers like the fmf powerbomb?


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Which bike and model year?  I see you're asking about the four stroke, but your signature says two stroke.
I purchased a new 2017 300SEF-R Six Days and the stock muffler was the most restricted unit I've ever seen. You wouldn't want that muffler with any head pipe.
If you don't have a performance system on now, you'll definitely want to remap the ECU when you switch it out.
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eagle

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Re: Exhaust Alternatives for 300 sef
« Reply #7 on: January 27, 2021, 02:30:29 PM »
The heading is, exhaust alternatives for 300sef ;)
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jamracing

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Re: Exhaust Alternatives for 300 sef
« Reply #8 on: January 27, 2021, 03:01:13 PM »
Hey all - is it worth replacing the header/muffler on the 300? Anyone have dyno numbers to show the bigger headers like the fmf powerbomb?


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Which bike and model year?  I see you're asking about the four stroke, but your signature says two stroke.
I purchased a new 2017 300SEF-R Six Days and the stock muffler was the most restricted unit I've ever seen. You wouldn't want that muffler with any head pipe.
If you don't have a performance system on now, you'll definitely want to remap the ECU when you switch it out.

Yup, just upgraded to a 2020 300 SE Factory, but also looking for a 2020/2021 300 SEF Factory...

This thread was prompted by reading about Cody's Endurocross 300 SEF, and was curious about the difference between the stock and FMF headers. I would rather it be as quiet as the two stroke, and how much power do i pay for that silence
2020 300 SE Factory

Rick

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Re: Exhaust Alternatives for 300 sef
« Reply #9 on: January 28, 2021, 06:20:02 PM »
The heading is, exhaust alternatives for 300sef ;)

Did ya notice it was missing the -R?
Thinking he might have keyboarded a F instead of an R...
 :-\
Your turn
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