XR650R E-series Midrange, Top end ??

I just installed a White Bros. E-series S bend slip on for my 650R.. It took the place of the stock exhaust and HRC tip.. I have a K&N air filter, B52 needle, intake, 68s, and 175 otherwise stock.. I feel stronger low-mid range power with the WB but it seems to sign off earlier on top.. Question is for some of you guys with this combo, did you think it actually increased the mid range that much or did it just hurt the top end making the mid feel bigger ?? The stock pipe seemed to have a flatter torque curve but this one has a "Bump" in the middle then seems to flatten out quicker in the upper revs.. It put the power in a good useable range but feels allot differant.. I hope someone has dyno sheets to verify.. thanks

i have had my bike on the dyno but haven't compared pipes on it. The "E" Series is very tuneable. I usually run 12 discs with a quiet core insert. that should easily give you more top end than the stock pipe w/HRC tip. How many discs are you running right now?

I have had the same experience with the e-series as you. I was running the stock pipe with the HRC tip and then I went to the S bend e-series and it had a stronger low end and mid range but is flater on the top end. I like the sound better from the e-series but I think the stock pipe with the HRC tip is actually hard to beat from a performance standpoint. It's hanging in the garage in case I want to change it out someday :applause:

Isn't the e series more free flowing than stock with an hrc tip? that would make me think that you would be running lean a high rpms and would lose power. when i installed my e series i also installed an fmf header and went to i believe a 180 main and found gains all the way through. shortly after that i installed a QS carb so i didn't run that jetting for more than a couple of weeks and i never fined tuned.

I am running 12 discs with the arrester plate.. I think the WB is more restrictive than the stock pipe, thus the improved low-mid and the decrease on top.. The power is good but it did flatten it on top, the sound is much better.. You feel as though you are short shifting it now to keep it on the pipe, but the mid feels much stronger, just a little harder to keep it in the sweet spot but when it's there it's pulling hard.. Guess you have to sacrifice something, if you open it up more free flow you will increase top end.. If you restrict it you get bottom end.. Needs an EXUP valve..

I never ran more than 8 discs in mine and never wanted for more power. With 12 you might be a little lean (depending on temp and altitude). I had the Pro Meg though. The megaphone design is a must have. If you've never ridden a XR with one you're missing out. WAY better than that HRC tip setup.

I never ran more than 8 discs in mine and never wanted for more power. With 12 you might be a little lean (depending on temp and altitude). I had the Pro Meg though. The megaphone design is a must have. If you've never ridden a XR with one you're missing out. WAY better than that HRC tip setup.

It's not lean I promise you that, If I ran 8 discs it would be choked to death puffing black smoke, if that was enough power for you maybe you need a 250, I'll take all the power I can get.. Matter of fact the plug has gone from a light tan with the stock pipe and tip to a darker chocolate brown with the E-series .. That says it all, the E-series with 12 discs IS in fact more restrictive than stocker/HRC tip.. And to no suprise thats why you get a better low/mid range performance.. As far as the megaphone type E-series I ran both types on my last dual sport bike (XR600R) and noticed little difference between them.. My conclusion is that you get better low-mid from the E-series but sacrifice some top end, which only stands to reason, your not gonna get both.. The stock pipe with the tip is perfect split the difference.. Am I gonna yank the E-series ?? Nope, it sounds too good... :applause:

There's a lot more to pipe design and power characteristics than just being restrictive or non restrictive. If it's major high rev top end you're looking for on a long stroke thumper... :applause: You might want to check into your choice of headpipes while you're at it.

I realize that, and I'm not looking for killer over-rev top end especially from a long stroke 650R.. But fact is you almost never get both.. It takes back pressure to help in the lower revs and more flow to help on top, you have to sacrifice somewhere.. Thus all the 2 smokes with the power valve in the exhaust, along with street 4 strokes like Yamahas with the Exup valve.. That lets them tune around the pipe a little.. But the WB pipe does flow less than the HRC tip pipe.. If you open it up your gonna get lean with a whiter plug, more restrictive and the plug darkens due to a richer mixture and cooler operating temp.. Have you guys never jetted any 2 smokes, you GOTTA read the plug.. It's all about combustion temperature.. :applause:

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