megabomb header

8 replies to this topic
  • crush6742

Posted August 21, 2010 - 05:32 AM


I was thinking about adding a Megabomb header to my '08 YZ450F, and leaving the stock exhaust pipe to save costs. Will this be a good investment? They claim it improves to bottom end an brings 5 more horse power.

  • crf450319

Posted August 21, 2010 - 05:59 AM


I've got a megabomb header on my bike and can tell you without hesitation that it doesn't add anywhere near 5 horsepower. If you want to improve the performance of your bike, the first thing I'd start with is replacing the stock can (muffler/silencer). They are incredibly restrictive and rob horsepower.

From my understanding the megabomb header is designed to broaden the power delivery throughout the range.

I'd almost guarantee that there's no header that will increase your hp by 10%, if there is... I want it !

If you replace the stock can, or better yet replace the whole exhaust system you could be looking at a 5 hp increase & you'll more than likely enjoy the power difference.

Good luck !! :bonk:

  • grayracer513

Posted August 21, 2010 - 07:35 AM


If you want from 4-8 more hp at around 5-6000 RPM, throw your stock muffler away and replace it with...almost anything.

Like the above post said, the PowerBomb won't do anything like 5 hp.

  • crush6742

Posted August 21, 2010 - 11:29 AM


What exhaust system would you guys recommend?

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  • Steel Panther

Posted August 21, 2010 - 11:36 AM


I run the megabomb with 4.1 system on my 09 and it works and looks great. Really wakes the bike up.

  • crf450319

Posted August 21, 2010 - 02:46 PM


I'm running an FMF Megabomb header with a Pro Circuit T4 slip-on. MRD, Dr.D pipes seem to be well liked. If $$ is an issue, start with a slip-on as you will see the biggest difference in power with that alone.

  • crush6742

Posted August 22, 2010 - 04:07 AM


Thanks for the feedback. I will look at replacing the whole exhaust stystem. I know this may sound crazy, but I want to ask anyway. The one thing I love about the stock muffler is it's small and hidden. Does FMF, Pro Circuit, or anyone else have a muffler that that is similar in size, but offers better performance? The one thing I hate about the four stokes is the huge muffler.

  • dvn

Posted August 22, 2010 - 04:50 AM


I also like the "out of the way" design of the shorty muffler. For that reason, I am running a megabomb header with a PMB endcap (with the cone removed) on the stock muffler. It is a nice gain over stock and fairly inexpensive. I'm sure a full system would be a bit more hp but I race +40 and +50A MX and this setup works fine for me.
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  • crush6742

Posted August 22, 2010 - 04:59 AM


That looks great!!!

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