2 Harleys, 4 Woods Cams, 2 Thunderheaders, 2 tuners and a day with Bob at RC Cycles
Would be nice to find out which Dyno Bob has.
Last edited by Faast Ed; Nov 7, 2009 at 09:58 AM.
Props to both tuner and JCleary.
Last edited by UltraKla$$ic; Nov 7, 2009 at 09:37 AM.
"The best" at starting debates and arguments, then deleting, changing posts to look like a saint. Loves to start threads on touchy subjects. The Master at baiting.
Pretty knowledgeable guy though, if he could only lose the attitude.
BTW: I do recall him bragging that he does all his runs in SIXTH gear! (splains your doubt in the numbers a bit?)
He claims it is the only "proper" way (even though your rear tire might come apart at that speed). Gear ratio @ WOT.
Last edited by Faast Ed; Nov 7, 2009 at 10:07 AM.
Both bikes are box-stock 96" motors except for cams, intake, exhaust and tuning.
Last edited by JCleary; Nov 7, 2009 at 11:28 AM.
Numbers were done on a dynojet with a SAE correction factor of .97.
Any given Dynojet model has the same roller, the same resistance, anywhere in the country by model. Period. It takes a given amount of horsepower/torque to spin a given weight up to speed in a given amount of time. This is a constant, and why a Dynojet is so good for comparing dyno numbers from location to location.
SAE correction factors are there to even the playing field, whether you're in the SF Bay Area with good air, or huffing thin air in Colorado. A Colorado correction factor might be 1.15.
Really the number that matters is UNCORRECTED horsepower. The SAE skewed numbers on the dyno sheet are LOWER than our bikes made yesterday. Add three percent to any of our numbers, and you get what OUR bikes put out YESTERDAY. On a 90 degree day, it will most certainly be different, much lower in fact.
Believe it or leave it, the bikes made what they made.
It's not like a pure eddy-current dyno, where you can actually tweak the resistance and skew numbers.
I learned a lot about dyno brands and styles over the past 6 years with my diesel truck addiction...
And the tuner is key. If your tuner doesn't have the experience, he will leave a LOT on the table. Run-to-run I could have a 10%+ difference in performance based on the settings of my fueling/timing devices in my Dodge. Only once did I have a magic day with 555/963 uncorrected fuel only. The torque curve looked like a HP graph though. I threw on a smaller turbo, changed some settings and dynoed again, lost 50hp and 20 tq, but the torque curve was flat as a table. Tuning is key.
Last edited by JCleary; Nov 7, 2009 at 11:31 AM.
JCleary, I thought I recognize the name, your on the DTR forum? I was a trainer for Cummins Diesel till I got laid off three months ago.
Last edited by JohnCA58; Nov 7, 2009 at 12:38 PM.
The Best of Harley-Davidson for Lifelong Riders
Any given Dynojet model has the same roller, the same resistance, anywhere in the country by model. Period. It takes a given amount of horsepower/torque to spin a given weight up to speed in a given amount of time. This is a constant, and why a Dynojet is so good for comparing dyno numbers from location to location.
SAE correction factors are there to even the playing field, whether you're in the SF Bay Area with good air, or huffing thin air in Colorado. A Colorado correction factor might be 1.15.
Nothing personal, but "any Dynojet" is NOT equal.
Do some research on the DJ250 "i" model that superseded the others.
The DJ150 gave you numbers that made you think you had a rocket bike.
The DJ250 became a little more accurate, but still generous.
The DJ250 "i" model became known as the "honest" dyno, and some even call them the "stingy" dyno. (I do). The TRUE ruler of comparison! (Winpep 7 software).
Then there is the "which gear" problem. MOST dyno tuners use 5th gear (on a 6 speed) and 4rth gear (on a 5 speed). Using any other gear skews the numbers.
Bob at RC himself told us at HTT that he uses 6th gear and feels it's "proper". (ask him yourself).
You aren't the only one who's spent a lot of time around dyno's, the difference is that I have been around "bike" dyno environments.
Your numbers look good and I would be proud. (yes we look at correction factors).
But 6th gear will make the tuner look better as well as a happy dyno.
Numbers aren't relative until you compare what the "before" numbers were (on the same dyno). Where's your base run? My tuner always trys to get a base run (before build).
Unless you plan on painting the numbers on your tank, all that TRULY matters is that your bike runs great!
You don't need to defend your numbers. We all know the bike runs great. The 6's are indeed a great cam. (And we know that Bob can tune).
.
Last edited by Faast Ed; Nov 7, 2009 at 01:32 PM.
Unless he's changed his methods,..... and I doubt that he has.
(Should be in the dyno notes, which gear the run was in).


