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Hi All. Just looking to get some feedback on the Dyno runs below. The graphs below are from before and after some performance upgrades I just had done. The bike is a 2003 Dyna Low Rider. The before\blue trace is basically a stock TC88 with V&H Long Shots and a Screamin Eagle (SE) Stage 1 air cleaner. The after\red trace includes the following upgrades; S&S 98” Big Bore Kit, S&S Ported Heads, S&S 583 Easy Start Cams, D&D Fat Cat Exhaust, S&S Premium Tappets, SE Premium Tapered Adjustable Push Rods, SE Hydraulic Cam Tensioner & Oil Pump Kit, Mikuni Carburetor HSR42, Roland Sands Air Cleaner, Dynatek 2000 Digital Performance Ignition TC88-2P. It looks like I gained about 33% in HP and Torque. I know I could have gained more with a different Cam like the S&S 585, but I preferred it over the entire RPM range rather than just kicking in at 3500 RPM. I still have the new S&S 585 Easy Start cam that I originally was going to go with and I may install it over the winter just to see if\how I like it; would I need another Dyno tune if I did that? Anyway, the bike is a completely different animal now and I'm thrilled with it... except the loud lifter noise the builder couldn't adjust away.... I will be following up with other professionals on that. Anyway, just looking for feedback\thoughts on if this is what I should have gained with this build. Thanks in advance.
Don’t take this the wrong way, but I think you still need another dyno tune... I know lean is mean, but I think you need to richen up the main. I bet that will bring up your peak torque, and boost the upper HP. What timing adjustments did the dyno guy try? Did he load in a custom curve? The power seems on the lower side for a 98” with ported heads. You should really be closer to or over 100/100.
Im surprised the bike even ran with the fuel curve on the “before” pull, he must have not had the sniffer in the right spot or something.
also, I’d look into rocker lockers or rockouts. I just put them in my 103, and they do make a huge improvement on the noise.
Something seems odd about the dyno results both before and after. I don't understand why your bike makes NO torque below 2500 rpm with the easy start cam. Even the before doesn't make anything at 2000 rpm..maybe an artifact or peculiarity of the dyno or it's set up (shrug). I just posted my dyno results for my 95 CI..at 2000 rpm it is making 100 FT/lbs of torque. I wonder if the easy start cams are not a bit to easy. But that does not explain the lack of torque on the before trace. (shrug)
What compression ratio do you have?
Another thought..you mentioned lifter noise..It's important to adjust the lifters on the heel of the cam AND also NOT on the easy start mechanism..go to the 8 minute mark of this S&S video..he explains it better.
The "no torque below 2000 rpm" is just a result of when the dyno operator hits the start button on the remote and cans it. He just didn't start the pull at a low rpm.
Originally Posted by EL in NH
Something seems odd about the dyno results both before and after. I don't understand why your bike makes NO torque below 2500 rpm with the easy start cam. Even the before doesn't make anything at 2000 rpm..maybe an artifact or peculiarity of the dyno or it's set up (shrug). I just posted my dyno results for my 95 CI..at 2000 rpm it is making 100 FT/lbs of torque. I wonder if the easy start cams are not a bit to easy. But that does not explain the lack of torque on the before trace. (shrug)
What compression ratio do you have?
Another thought..you mentioned lifter noise..It's important to adjust the lifters on the heel of the cam AND also NOT on the easy start mechanism..go to the 8 minute mark of this S&S video..he explains it better. https://youtu.be/5q5mg0C4Rfg
The "no torque below 2000 rpm" is just a result of when the dyno operator hits the start button on the remote and cans it. He just didn't start the pull at a low rpm.
Originally Posted by EL in NH
Something seems odd about the dyno results both before and after. I don't understand why your bike makes NO torque below 2500 rpm with the easy start cam. Even the before doesn't make anything at 2000 rpm..maybe an artifact or peculiarity of the dyno or it's set up (shrug). I just posted my dyno results for my 95 CI..at 2000 rpm it is making 100 FT/lbs of torque. I wonder if the easy start cams are not a bit to easy. But that does not explain the lack of torque on the before trace. (shrug)
What compression ratio do you have?
Another thought..you mentioned lifter noise..It's important to adjust the lifters on the heel of the cam AND also NOT on the easy start mechanism..go to the 8 minute mark of this S&S video..he explains it better. https://youtu.be/5q5mg0C4Rfg
06-19-2018, 10:51 AM
Thoughts on Dyno After Upgrades
