|Posted on Saturday, August 14, 2010 - 08:29 pm: ||
I have an 06 XB9SX, with a K&N, Race ECM and Buell Race Exhaust.A recent trackday has brought to my attention a condition which has never come to light while street riding.I don't push hard on the streets....
There seems to be a "lack of power" or a soft spot in the power band in the neighborhood of 3500 to 4500 RPM's. The bike would seem to pull fairly strong until about 3500, slowly gather speed until about 4500, then of course,around 5000 would start to pull very well.
I suppose with more skill on my part I could bypass this condition, but I don't feel comfortable on some corners to have the RPM's around 5000 at the entry..
SO anyway, my question is:
Is this a tuning issue that I could hammer out, or what can I do to eliminate the soft spot I have found.
(Message edited by loud_and_low on August 14, 2010)
|Posted on Sunday, August 15, 2010 - 12:16 am: ||
Somehow, you're making the whole process sound very slow for a race bike.
Try riding a gear lower so that you're always above 4000. Let the rpm determine the gear you're in, not the other way around.
It's meant to be a high revving engine.
|Posted on Sunday, August 15, 2010 - 05:08 am: ||
I'm no expert...but I think there is something about a "white wire trick" but maybe that was on euro only models...."9's" are known for that flat spot...
I think I read somewhere that it is a timing trick for epa smog or noise reduction.
It can be largely tuned out...contact E.B.R they have the technology.
|Posted on Sunday, August 15, 2010 - 07:29 am: ||
The "flat spot" is notorious with certain aftermarket exhausts on XB9, from the very beginning, especially the Buell Race Muffler. I ultimately chose a better muffler for trackday use, to gain some powerband flexibility. Go to American Sportbike's "Exhaust Shootout", and you can see the dyno charts for yourself: http://www.americansportbike.com/Exhaust_Shootout. html
"It can be largely tuned out"
Not with that Buell Race Muffler; its chronic. And there is no "white wire trick" either, except possibly on heavily restricted Euro models.
(Message edited by nuerburgringer on August 15, 2010)
|Posted on Sunday, August 15, 2010 - 08:11 am: ||
That Exhaust shootout is excellent. Thanks for that. It certainly does corroborate my thoughts of the "flat spot". The race muffler graph shows exactly what I felt.
At this point I am thinking I have 2 options.
1. Contact Erik Buell Racing to find out what their solution is.
2. Pony up for a new muffler that has a more linear response.
|Posted on Sunday, August 15, 2010 - 03:49 pm: ||
Drummer and custom tune, theres my opinion
|Posted on Tuesday, August 17, 2010 - 01:12 pm: ||
yes you can help the dip but its going to need tuning in the timing table and the maps as well as one other area.
next you need to look at the American Sport Bike shootout xb9 pipes and pick a pipe that fits your riding rpm zone.
i cant stress on how many dont match the pipe to how they ride which can yield a more than less perfect use.
|Posted on Thursday, August 19, 2010 - 12:58 pm: ||
|Posted on Thursday, August 19, 2010 - 04:59 pm: ||
Opinion 1: Make it right, before you "tune" it.
Professional advice: SET YOUR TIMING. "Off" timing causes EXACTLY what you describe. It has nothing to do with EPA or any of that, it's just a fact that the timing isn't always perfect. Remember, it controls BOTH spark AND injector timing on your bike, and on a common manifold, that means that one cylinder is being overfed and the other starved when your timing is off!
Example? I "cured" (magically) an XB9 just a few days ago that exhibited similar symptoms. Timing timing timing. Set it by the book!
|Posted on Saturday, August 21, 2010 - 09:13 am: ||
From my experience on my 9 with buell race ECM and race pipe and cleaner....
From idle to about 3700 is smooth but not real peppy.
Right at 3700 it's like hitting a switch! You get that "thrown back" feeling and she pulls like a train until about 3 or 400 under redline.
No flat spots... Just not full of life until just a hair under 4 grand.
|Posted on Saturday, August 21, 2010 - 04:51 pm: ||
Ditto to Rah7777777. I couldn't have said it better. My experience exactly.
|Posted on Saturday, August 21, 2010 - 05:08 pm: ||
When I checked my static timing last year it was off a hair, but not too much.
Maybe yours is off??