current wr, full system or slip on.

How much more will u gain going with say a fmf full system vs just a slip on. Is it worth the money? I dont race but i like to be conpetitive.

Full system if you can afford the header. More power everywhere.

Yes, as JDL said, more everywhere.

Jet and airbox mod to match.

Yes, as JDL said, more everywhere.

Jet and airbox mod to match.

airbox mod? please explain

airbox mod? please explain

Remove the snorkel piece under the seat. A few screws and comes right out.

FWIW I just did Q4 slip on. I don't race, and don't find the bike hurting for power in any way. I ride mostly tight woods so power delivery is more important than quantity. YMMV

just found a yosh full system for 10-13yz450. but i cant find if it will fir the 13 wr. nope just remembered yz is rear exit. cant tell if the slip on would work but doubt it.

Edited by EdgeR6

Im looking at the fmf pipe with the titanium mega bomb header cuts a couple of kgs off the bike plus adds another 7 or so horse power also looking at having it rejetted at the same time.

My ride is a 2011 wr450f

Are the full systems a straight header or do they incorporate the canister in the header like the new stock Wr's?

Just looked at Dr. D's wedsite and their pipes do have the canister on the header like the stock. I remember one of the bike reviews saying something about needing to add the canister to make up for the low end loss when they went to FI. I assuming going with a header not having the canister would result ina loss of power down low???

Just looked at Dr. D's wedsite and their pipes do have the canister on the header like the stock. I remember one of the bike reviews saying something about needing to add the canister to make up for the low end loss when they went to FI. I assuming going with a header not having the canister would result ina loss of power down low???

It doesn't matter what 'features' the pipe has, it's all about the motor character.

A resonant chamber (the 'canister' you keep referring to) is there for different reasons on different pipes.

Mostly, overall, it's purpose is to simulate a longer header, and to create an out-of-phase resonance, that cancels out 1 or 2 db sound, with no loss in torque.

But picking a pipe is like picking glasses. You can't possibly know what prescription without knowing EXACTLY what you already have.

That's why jetting, airbox, TPS, ACV, riding style, riding area, experience, etc, all play a part in choosing the pipe system.

For example:

Dr D pipes flatten the power, spreading it across the range, with virtually no peaks. Makes any bike easier to ride, but it is not the highest HP (as if that matters).

On the other end of the spectrum, Yoshimira pipes are designed for MAX HP output, which is usually around 7-8k rpm. Not trail rider friendly, unless you like to spin the rear wheel and slide and hit berms often.

Pro Circuit is about half way in between.

FMF is all over the map. Some of their pipes radically decrease back pressure, making a poorly jetted and plugged up bike run better (stock WR), but with a properly un-corked and jetting motor, the power is lackluster, and not snappy.

There there are pipes like DG, Lexx, Jardine, etc etc, which really aren't engineered at all. They are just designed to 'sell' and they are inexpensive.

Some are copies of other older brands (White Bros, XR's only, etc). Some work very well, but overall, you are buying on price, not value.

You can go with whatever pipe you want, but, if you want positive results, you should start reading posts, reviews, and manufactuers websites, so you know what you want, how to make it work, and how to get there.

I like Dr D because it responds very well to cams, porting, carb mods, without any compromises, and speeds up the revs with it's gradated megaphone design.

I don't like FMF because they usually slow down the rev's and have an un-even power delivery.

IMHO

Edited by Krannie

It doesn't matter what 'features' the pipe has, it's all about the motor character.

A resonant chamber (the 'canister' you keep referring to) is there for different reasons on different pipes.

Mostly, overall, it's purpose is to simulate a longer header, and to create an out-of-phase resonance, that cancels out 1 or 2 db sound, with no loss in torque.

But picking a pipe is like picking glasses. You can't possibly know what prescription without knowing EXACTLY what you already have.

That's why jetting, airbox, TPS, ACV, riding style, riding area, experience, etc, all play a part in choosing the pipe system.

For example:

Dr D pipes flatten the power, spreading it across the range, with virtually no peaks. Makes any bike easier to ride, but it is not the highest HP (as if that matters).

On the other end of the spectrum, Yoshimira pipes are designed for MAX HP output, which is usually around 7-8k rpm. Not trail rider friendly, unless you like to spin the rear wheel and slide and hit berms often.

Pro Circuit is about half way in between.

FMF is all over the map. Some of their pipes radically decrease back pressure, making a poorly jetted and plugged up bike run better (stock WR), but with a properly un-corked and jetting motor, the power is lackluster, and not snappy.

There there are pipes like DG, Lexx, Jardine, etc etc, which really aren't engineered at all. They are just designed to 'sell' and they are inexpensive.

Some are copies of other older brands (White Bros, XR's only, etc). Some work very well, but overall, you are buying on price, not value.

You can go with whatever pipe you want, but, if you want positive results, you should start reading posts, reviews, and manufactuers websites, so you know what you want, how to make it work, and how to get there.

I like Dr D because it responds very well to cams, porting, carb mods, without any compromises, and speeds up the revs with it's gradated megaphone design.

I don't like FMF because they usually slow down the rev's and have an un-even power delivery.

IMHO

Good info. I was going off of one of the bike reviews (12' Wr450) where they mentioned needing to add the resonant chamber to compensate for the loss of low end since they switched to FI. I have A Dr. D pipe off my old Yz450 that I will put on the new Wr I just bought but was going to leave the stock header as I thought it would be better than the Dr. D header. I'll try both to see what the difference is.

I disagree with the LEXX. IMO it is the best option for a quiet pipe out there. I have had FMF Q4.. it was OK, but the LEXX is much quieter. I don't like loud pipes, it closes riding areas.. which leaves few options.

I disagree with the LEXX. IMO it is the best option for a quiet pipe out there. I have had FMF Q4.. it was OK, but the LEXX is much quieter. I don't like loud pipes, it closes riding areas.. which leaves few options.

Every brand offers a quiet tip insert of one or more db levels.

Two Bros offers 5 different ones!

I put an FMF Ti PowerCore slip-on on my 2005 WR450 about 7 years ago. After some fine tuning with the jetting, the power difference was very noticeable. I haven't even considered swapping it out since. Best $300 I've spent on that bike, without a doubt.

I put an FMF Ti PowerCore slip-on on my 2005 WR450 about 7 years ago. After some fine tuning with the jetting, the power difference was very noticeable. I haven't even considered swapping it out since. Best $300 I've spent on that bike, without a doubt.

I had the same on my '07 since day one, never rode it stock. Just a month ago did I replace it as it was time with all the tip-overs. This time around I went with the Yoshi slip on and I love it. A bit more quiet than the

FMF was .

motoworks has the full sr4g2 exhaust for sometimes $400. This Is the same system used by championship winning racers. 2006-2009 yz and 2007-2013 wr exhaust will fit.

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