Bonneville America Forums Forums Technical Forums Performance Mods FINALLY!! RoundSlide's Dyno Results (Long)

Greetings All,

Finally, FINALLY got a dyno run in this Saturday at a Suzuki / Yamaha Dealership in Mobile, AL. I'm going to try posting the pictures, and then show my bike's settings in the MPG Survey Format:



MPG: 31 or 32 Street, 38 Highway
Best Horsepower: 60.39 @ 7900 RPM (Out of 3 pulls)
Best Torque: 46.58 @ 5000 RPM (Out of 3 pulls)
Pipes: Decibel Reverse Megaphone Pipes (English and Loud!!)
Airbox: gone; Freaked with pre-filters
AI: Removed
Jets: 115 Main Fuel / 230 Main Air / 55 Slow Jet
Plugs: Stock spark plugs
Carbs: Keihin 35mm CRS RoundSlide carburetors
Needles: CRS 5183, 3 notches down
Drive: Chain - Stock X-Ring (16T front/44T rear)
Other: Stage I Equivalent Cams
Elevation: 10 or so ft above sea level
Temperature at Run: 85.8 Degrees Fahrenheit
Barometric Pressure: 29.84" Hg
Humidity: 36%
Mileage at time of Dyno Runs: 14,925

Commentary: My biggest hindrance was apparently operator error with respect to my jet settings; the operator told me that the bike was running incredibly lean. Regretfully, for legal reasons, they were unable to provide me with the Air / Fuel Curve superimposed on the printout, so I can't show you guys where the thing goes wacky. You'll notice the place around 3600 RPM where HP and Torque fall through the floor, this corresponds with the biggest spike in air per fuel. The operator seemed to think I could see an easy 65HP if my settings were richer. Regardless, bike pulled great, sounded great, and if you can manage to overlook that one dip, you'll notice that torque stayed between 40 and 44 ft-lbs through the entire spread. HP NEVER tapered off, and was still climbing until the rev limiter kicked in. There's the visual justification of the cams / carbs, too bad there's not a readily available ignition that will let me spin higher (hint hint, aftermarket!) Very happy with my results, now it's time to rejet!

2003 Kawasaki 1500 Vulcan Classic



MPG: 40 or so Street, 45 Highway
Best Horsepower: 59.06 @ 4600 RPM (Out of 3 pulls)
Best Torque: 77.91 @ 3100 RPM (Out of 3 pulls)
Pipes: Cobra Lo-Boy Shotgun Exhaust
Airbox: Replaced w/Coyote Airbox removal kit, K&N Air Filter
AI: Reed Valves removed / blanked with Sherms Cycle Coasters
Jets: DynoJet Kit, 165 Main, 48 Pilot Jet
Plugs: Stock spark plugs
Carbs: Keihin 40mm CVK Single Carburetor (Stock)
Needles: Stock, 2 shims underneath
Drive: Shaft, final drive ratio unknown
Other: Idle Mixture screw 3.5 turns out
Elevation: 10 or so ft above sea level
Temperature at Run: 89.83 Degrees Fahrenheit
Barometric Pressure: 29.84" Hg
Humidity: 30%
Mileage at time of Dyno Run: approx. 14000

Commentary: This is my best friend's ride, his tuning was pretty much spot-on. We found out that his bike has a Hard Rev Limiter that kicks in 6200 RPM, makes a very dramatic backfire with ensuing fire coming out the pipes.

2003 Suzuki Intruder Volusia 800



MPG: 45 or so Street, 50 Highway
Best Horsepower: 45.62 @ 6000 RPM (Out of 3 pulls)
Best Torque: 45.77 @ 4000 RPM (Out of 3 pulls)
Pipes: Stock
Airbox: Removed, UNI Air Filter UP4245 Installed
AI: Moccs Pair Valve Removal Kit
Jets: DynoJet Kit, 150 Main, 45 Pilot Jet
Plugs: Stock spark plugs
Carbs: Mikuni Single Downdraft Carburetor (Stock)
Needles: DynoJet Needle, 3rd notch down
Drive: Shaft, final drive ratio unknown
Other: Idle Mixture screw 3 turns out
Elevation: 10 or so ft above sea level
Temperature at Run: 92.43 Degrees Fahrenheit
Barometric Pressure: 29.84" Hg
Humidity: 28%
Mileage at time of Dyno Run: approx 9000 miles

Commentary: This is my best friend's wife's bike, and incidentally the only one with stock exhaust, had a really nice exhaust note without the volume that the other two bikes had. Mixture rich throughout entire range, but gives best running, bike has NO apparent Rev limiter, and was Revved to 7600 rpm, well beyond power drop-off.

Comments / suggestions / so on so forth are welcome! I'll say now that based on my results I'm no longer qualified to give recommendations on jet settings for CRS carbs, so kindly keep that in mind if I ever to give tuning suggestions.

Cool, the pics actually posted, BonnyUSA thanks for the post in the "help" section about posting pictures, that made this whole drill a heck of a lot easier. Of final note to the dyno runs, tire wear was negligible for all three bikes, there was about a 2" wide strip of new wear from the rolling road, after another hour of riding, the dyno wear was indistinguishable from the already-present tire wear. An all-around fun experience!

Thanks for the post Roundslide. Two questions. Are those the cams you got from Matt Capri at Southbay? Do you have plans to rejet soon and go back for another dyno run?

These cams are a grind that the Triumph Dealership in Pensacola came up with, and as far as I could tell, have no connection with South Bay Triumph. When I bought my Speedmaster, these cams were already installed. Yes, I do plan on re-jetting, I'd already ordered some richer needles before I did the dyno runs, so as soon as I can get the needles in, I'll re-jet and re-tune completely. I'd like to do another run soon before it starts to actually get cold, otherwise, I'll just wait till spring of next year.

Thanks for your comeback, have a good one!

RS,
To get rid of the 3.5k dip, change the needle diameter to a thinner needle, keep the taper close to what it is now though. This will richen up that area nicely and get rid of the big dip in torque and power.

Yeah, I'm also going to try to see if I can richen up the slow circuit so that it maybe might have more overlap on to where the needle takes over. Right now I'm running the leanest needle available for the carbs, the ones I'm waiting for are a little more aggressive, I'll probably stay at the same "notch" with the new needles, then go up to 120 mains from the 115's that are in right now. Too bad though, my fuel economy is already pretty low, guess it won't be getting any better anytime soon!

Thanks for the input!