Choosing an Exhaust

I just bought a new WR450..all stock..in process of doing all mods to unleash the power...I have a question, I need a spark arrester on the bike and for it to pass sound test..

Do I just buy the $60 pro motion insert? Or go with a new sparky ($300+)?

The insert claims 6.3 hp gain...how much more gain will I get if I buy an

FMF Q w/sparky?

Your new wr450 should already have a sparky and is green sticker legal

Just modify your existing muffler.

Thanks, but maybe I should re-phrase my question...

Who here has converted the stock exhaust and added the pro-moto insert for $60 and then bought a aftermarket pipe (without header).??.

Did you notice a great amount of power gains??? And what exhaust did you try? I'm trying to save $$$ to get other things done...suspension, etc..thanks.

Well... I do. I have an FMF factory 4 pipe. i bought my bike used with it on already. That pipe, far as I could tell, was absolutely great. No bogs, no power loss, good on the top and bottom. But especially on the top.

However, I find drag racing down fire roads extremely boring, and I prefer trails. So I usually ride no more than 35mph before I get bored. But, that is pretty fast considering the trails.

I am running in my first enduro next week (Ghost Riders). So I put back on the stock header and pipe, removed the inner baffle and gave it a try. For my type of riding, I can't tell the difference. But if you are into drag racing...

There is one major difference though... the stock pipe with the baffle remove is a lot quieter. Its AMA legal and friendly to those around you.

I would think that only the best riders would really notice a real difference. I will probably sell my factory 4 pipe.

Well... I do. I have an FMF factory 4 pipe. i bought my bike used with it on already. That pipe, far as I could tell, was absolutely great. No bogs, no power loss, good on the top and bottom. But especially on the top.

However, I find drag racing down fire roads extremely boring, and I prefer trails. So I usually ride no more than 35mph before I get bored. But, that is pretty fast considering the trails.

I am running in my first enduro next week (Ghost Riders). So I put back on the stock header and pipe, removed the inner baffle and gave it a try. For my type of riding, I can't tell the difference. But if you are into drag racing...

There is one major difference though... the stock pipe with the baffle remove is a lot quieter. Its AMA legal and friendly to those around you.

I would think that only the best riders would really notice a real difference. I will probably sell my factory 4 pipe.

Thanks...that's more of an answer I was looking for....I already removed the baffle, haven't riden it yet...suspension being sent in.

Any other responses would be appreciated..

I had a stock pipe, put the PMB insert on it, had it that way all summer. Felt sluggish and sounded brutal (we don't have sound issues here); put on a PowerCore4 Ti and I absolutely love it. Just my 2 cents...

I have a 06 wr450 with all the free mods,AIS, promoto insert and jd jet kit and love it power on demand everywhere from single track to desert and its quite.

I would NOT buy my Big Gun Evo X again,

Insert or FMF Q- both are quiet.

Thanks..I think I will buy the insert and run it...And LATER if I need MORE power, I might splurge for the fmf Q....Isn't it also lighter than the stock exhaust????

I have the FMF Q2 muffler along with the free mods. It is quiet and has unleashed the hidden power in this bike. I recently added the powerbomb header (supercross model) and found it to add a noticible midrange hit, just about the time I would have shifted. It actually adds more rpm's and extends the pull in each gear.

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