Finally finished uncorking my R

I did all the mods except the removal of the exhaust baffle (to be nice to the neighbors), but today I took out the spark arrester as a unit...........holy crap!

I didn't expect much difference, besides noise, but the difference was huge. Now I am thinking about an aftermarket head pipe and exhaust. What can I expect from a new exhaust versus a totally open stock exhaust? The open stock unit is a little too loud for my taste.

I would like an aftermarket pipe that is a happy medium between stock restricted and stock open exhaust (spark arrestor removed). Something that sounds low and smooth (loud is OK) but not tinny and with that rattling sound.

Any advice?

What have you been happy or dissappointed with?

I was thinking FMF with a powerbomb or maybe a yoshimura pipe with stock head pipe. Or maybe a white bros so I could tune it myself.

Go with a White Bros Pro Meg. Tunable, megaphone, great power. I think a lot of people miis the boat with open non tunable exhausts. They're great for wide open high speed stuff, but you lose out on that wonderful, useable low end and mid range grunt that only a megaphone shape brings to the party, and makes the big XR so fun.

I like my FMF Q..Good tone not loud.......The BRP is pretty sweet uncorked right.. :):)

The White Brothers "E" series is the best all around muffler. I don't run it but, it is the best for tunability. You can go from a wisper to full on killer loud! It comes just about right with all 12 disks and the back plate on (spark arestor). Not real light like the R4 and T4 but, the R4 and T4 are not tunable.

I was having a great off line discussion about horsepower and where

you can move it and how much you can add and where with different header muffler setups. Lots of rambling

and I am sure there is some small mistakes but, food for thought for

you horsepower mongers ;o) This is a cut and past of some of it.

With just changing the muffler tip, you get more hp but, look at the

dyno charts and the horsepower mod's page

and you will see that it starts to flatten out @4000 rpm. You should


gott'n more everywere but, not a full 20hp climb between 3,500 and

5,500 rpm.

That is what I am talking about when I say, mid rpm hit. Your setup


on longer then stock by far but, falls flat @ 5,000rpm. This is

where the extra 4hp pops up on the final horsepower numbers at about

5,600rpm to the end. I went through all

of this step by step, over and over again with three BRP's. We

tested Stock

head/2" tip, Stock/ header "E" series, xr's only header/R4. The big

problem with this testing is the XR's header/R4 setup always has had

a pumper carburetor on it. This setup (XR's head/R4 muffler) we tried a Mikuni TM40, Mikuni HSR42, Stock Edelbrock, 42mm X 40mm Edelbrock and now it's on a different XR650R with a stock Edelbrock. This does make a better low end. It is

allways informal. The Stock/

header "E" series was the most responsive in the low rpm's and held


longer then the stock/2" tip. It had 12disks no back plate (wide

open), The

XR's header had a much harder punch @ 4,000+ rpm. Over all top


reading from the 2" tip to the XR's/R4 setup (with pumper carburetor, holes in the air filter cover) was only 4hp but, there


places in the curve that there is over 7hp difference! There is a


horsepower difference @ 4,500 rpm with a stock 2" drilled out setup


Header/R4. Everyone talks about losing bottom end torque but, with

the BRP

any mod you do you gain torque everywhere. But, you gain more up top

compared to what you gain at the bottom. You never lose torque with


modifications (if jetted right) to this bike. Just "Feels Like It" . at 2,400 rpm you

may only

gain .5 foot pounds of torque but at 5,200 you gained 10! (HRC tip


header/R4 with holes in the side cover) All having free flowing air


Look at the torque chart half way down this page:

The White Brothers "E" series is the best all around muffler.

Did you say I did something right? And bought the best ?


he he

you rock BWB :)

White Brothers has discontinued the ProMeg. They aren't available any more, at least from White Brothers. There might be a few dealers with 'em still on their shelves, but I think it'll be tough to get parts for 'em, or get them fixed/ replaced in the event of a failure/ break. Too bad- I think they were probably the best all-around pipe. I just missed getting one- as of last week they had 9 on hand, this week- zero. Dang!

I would try XR's only and/or Thunder alley. I think they both make a megaphone design. :)

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