You didn't give much of a description of the head work. And we can't see the curve or test conditions without the sheet. SAE? Smoothing? What gear? Etc...
I'd have expected to see 110/120 out of that 107 if I was just WAGing. But dyno's and the way they're operated will vary.
Seems to me if you are going to spend the bucks, why not get the most out of it you can? One of the main issue's in my opinion is that there are thousands of dyno operators, but probably less than a hundred quality tuners. It pays to find a good one. For comparison below is my 103. A 107 with heads and cams should outperform it shouldn't it?
I wondered the same thing about the TB. The 777 cam and the 24d I'm running aren't very far apart from each other. Truth is I'm disappointed with my numbers too but it's fun to ride so that's what I going to do. Not worry about the numbers and just enjoy what I have because it really is a big improvement over the stage 1 103. On the dyno and by the seat of the pants.
When I had my 107" dyno tuned I told him I was only interested in having it perform across all RPM and throttle position ranges. I didn't care about the numbers, I just wanted it to pull smoothly everywhere. When I picked it up we didn't even talk numbers, I told him I didn't need to see the sheet, if it did not run correctly I would bring it back. The tuner liked the build and asked me for all the details of the cam and head work. The bike runs flawlessly and pulls strong everywhere so I have not been back for a re-tune.
When I had my 107" dyno tuned I told him I was only interested in having it perform across all RPM and throttle position ranges. I didn't care about the numbers, I just wanted it to pull smoothly everywhere. When I picked it up we didn't even talk numbers, I told him I didn't need to see the sheet, if it did not run correctly I would bring it back. The tuner liked the build and asked me for all the details of the cam and head work. The bike runs flawlessly and pulls strong everywhere so I have not been back for a re-tune.
Now that is some wisdom to follow right there, well said!
Well, the magic numbers that always used to be talked about were 1 HP per cubic inch. You are very close, and as stated the differences in dynos can explain a lot.
In my opinion (and I am BY NO MEANS any type of expert at all) looking at the sheet you posted I wonder if the early torque numbers wouldn't be better if the AFR in the same RPM range weren't as lean as shown. A little richer, closer to 13.8 or so, may make a bit more power. The curve maybe a little quicker to the high number, in my useless opinion.
Either way, ride it like you stole it!! Looks like a great ride!
I would agree with that estimate of the afr down low. I'm never at 100% throttle at low rpm anyway. From my understanding that dyno runs like this are measured at full throttle.
03-10-2019, 09:18 AM
