Contributing Writer: Frank Morton
After much careful deliberation (meaning a long period of indecision) I decided to have my Yamaha WR250R dyno-tuned, so I scheduled an appointment. I learned a lot throughout the process, but the most important lessons I learned were: any moron can buy a dynamometer but that doesn’t necessarily mean he’s proficient with it, and sometimes numbers are just numbers.
I should probably start at the beginning of the process, but I’m impatient, so here’s a printout of the end result:
Yes, you’re reading that correctly: 22.5 HP between 8 & 9,000 RPM. What the hell? Did all my mods result in an overall power loss? Thought I’d read in several publications that a stock WR250R was putting out somewhere in the neighborhood of 24 HP. (Editor’s note: There’s a longstanding debate over the validity of ‘claimed horsepower’ by manufacturers, with many believing the numbers have been fudged to help sales figures) I sort of mentioned this to the “technician/shop owner” that ran my bike, and got a definitive, “No, they don’t”. Based on this and some other comments he made about the WR, I assumed he was some sort of an expert on the bike. Then he asked me if it was “a street legal bike”, and all assumptions about his expertise on my bike when right out the window. Ah, but wait, there’s more incompetence to come!!!
But before I go there, the bottom line is that I am extremely pleased with the end result, regardless of the dyno numbers. Power is up noticeably, and fuel mileage went from as low as 36 MPG to between 45 & 50 MPG, depending on how I ride it. The increase in power and fuel mileage makes me strongly believe that my bike is running at its peak performance, which should only add to its reliability and longevity. Would I recommend that anyone else with an EFI controller and/or any other mods done, dyno-tune their bike? YES, without hesitation. But not at the shop I took it to.
Sooo, from here I’ll go into that, but I’ll warn you now, it’s a long sad story about a boy and his dog. Or in this case, and old man and his dual sport. If you chose to read any further, grab a cup of coffee and a hanky or two, and be prepared to find either a comedy of errors or a tragedy of incompetence.
I’ll start with a quick recap of the mods done to my WR250R: Power Commander III USB (with PC IV software cut and pasted into it), opened the air box, pulled the EXUP system and installed the 12 O’clock Labs replacement module, gut the stock exhaust including catalytic converter, and opened the exhaust tip to 1 1/8th inches. Total cost, about $280. One significant reason for dyno-tuning at this point in the modification process was to see just how close I could get to other WR’s with an aftermarket (see: expensive) exhaust system.
My story begins with a call to the shop that has a dynamometer. Can I bring my bike in for a tune? “Well sure, just bring her on down and we’ll get to it as quickly as possible.” Worst case scenario, I’m told, is a week, but “that ain’t gonna happen”. Six business days later I call and, “Oh, we stuck your bike in the back and out of sight is out of mind”. The call ends with the promise that they’ll get to it that afternoon or the next morning, and with me thinking, do we not know about service documents or scheduling appointments?
At this point, let me explain some of the conversation I had with the ‘tech’ about tuning my bike. As stated, he asked if my bike was street legal. Hello – license plate and turn signals might suggest that it is, but hey, I do get knit-picky sometimes. He told me he never tunes a dirt bike with knobbies as the results aren’t always accurate. Now looking at the WR, does it not scream dirt oriented bike? And aren’t the Dunlop D606’s I run more or less knobbed up? Perhaps being DOT approved removes them from the knobbie class.
I mentioned my desire to compare my bike (exhaust system) against other aftermarket systems, to which he explains that “We really like the FMF system on the WR, but they’re no longer available”. What, the WR or the FMF? Again, WTF?
Our conversation continues toward me eventually installing a Thumper Racing 280 big bore kit. He tells me he’s never heard of Thumper Racing. I look down into the glass display case between us and, bigger than life, a custom part of some sort with the words Thumper Racing engraved into it. Keep in mind that this is not only the tech, he also owns the shop!
At this point, don’t you think I’d have enough sense to just cut and run? Nope, not me. I’m in this for the long, albeit increasingly painful, haul.
After the tuning is finished and I’m handed a receipt, I ask for some sort of printout of the results. The owner/tech seems a bit confused by this outrageous request, but disappears into the shop, digs around a bit, and finally produces the printout posted above, then by way of excuse he states that the dynos Bluetooth isn’t working. Then I ask for the results of a pre-tune run for comparison, assuming he had done one, which quickly reminded me that my assumptions up to this point haven’t worked out very well. This was no exception; none run. I question the results and besides being told that WR’s don’t make 24 HP, “my dyno runs 10-15% low”. Have we never heard the word “calibration”?
Being the cranky old fart that I am, I’m pissed. And I stay pissed until my son-in-law asks me, “But are you happy with the results?” Well, crap…yes I am. My bike runs GREAT. And as I said, power and fuel mileage are up noticeably, so I got the most important results that I was after. Will I ever go back to that shop? Not even for a tire pressure check.
After all of this, I learned (or relearned) a very important lesson – performance modifications are only one part of the big picture and results shouldn’t necessarily be defined by numbers alone. What I initially wanted was a great handling bike on and off road, decent range, relative comfort, and adequate power, all at a reasonable price. I now have that in my WR250R, in spades. So much so that I’ve decided to break the dual sport barrier and expand my riding into the world of (somewhat limited) adventure touring. With the help of some Tusk Panniers and Rotopax Fuel Pack, I look forward to heading out in a cloud of dust to points unknown, just as soon as the snow melts.
About the Author: Life-sized action figure and scientific anomaly Frank Morton enlisted in the Marine Corps the day after graduating High School and went to Vietnam. After his Tour of Duty he joined the Oregon State Police and spent several decades fighting crime and scraping dead people off highways. Now retired, he divides his time between exploring the back roads of Oregon and repairing the damage he’s done to his dual sport in his workshop, all while ingesting copious amounts of coffee.