A local dealer is having a sale on the White Brothers R-Series slip on for the Raptor for $219. I can't find any info on the White Brothers web site that talks about the difference between the E-series and R-series pipes. The E-series is advertised as giving your more low-to-mid range power, but how is the R-series different?

Thanks,
Lorrin Lee

The difference is that the e-series is designed for a 4-stroke engine that will overall kill the r-series in hp and torque. The r-series is a product of demand.
The R-series is a straight-thru pipe (similar to no silencer at all) that will increase low-mid torque and HP with little or no gains on top end...the reason the r-series is for sale is because the new "fad" is to stick a 2-stroke type silencer on a 4-stroker.
Look into the recent magazine pipe/silencer tests for the 400ex. The e-series really shines.

i'm VERY happy w/ my e-series. Probably louder pipes w/ more HP out there, but i'm dealing w/ sound limits at the Oregon dunes at 93dB. my pipe w/ all discs (12) comes in at 95dB, so it's very "iffy". Anyway, the pipe looks great, easy to install and BIG difference in power ( could there be a more choked-up pipe than the stocker?) garyc660r is correct: HUGE gain in torque over stock, or it just felt so.
155/150 mains w/ 27.5 pilot did the trick ( WAY too lean before ) and only snorkel tabs cut. Runs awesome. Ordered the Graydon aluminum open airbox for the raptor. cannot wait. late.

Trublue.....what elevation do you ride at?

live at 900, but ride into mountains from house, climbing to 'bout 3800ft. ofcourse my fav spot are the oregon dunes at... um...??...huh...
YA ! SEALEVEL !!
out

A recent dirtbike magazine did a big shoot out on pipes for the new YZF250 screamin four stroker, the E-series sucked where as the R series produced a strong power gain, differnet engines respond to different exhaust systems, what works good on a 400EX may not be the "ticket" on a Raptor..............