HOME OF THE $125 DYNO TEST!
BUILT ON DECADES OF DIRT, GREASE & DYNO PULLS.
Performance tuning, dyno testing & powersports modifications in Rochester Hills, MI. We don't guess what works. We measure it.
WHAT WE DO
Thirty-plus years of pulling things apart, figuring out what makes them faster, and putting them back together better. Every modification gets validated on our in-house dynamometer.
DYNamometer TESTING
State-of-the-art chassis dyno with high-speed data acquisition and ETAS Lambda air/fuel analyzers. Our $125 dyno session tells you exactly what your machine is making, not what the spec sheet says it should.
PERFORMANCE MODIFICATIONS & TUNING
Carburetor jetting, EFI mapping, fuel and spark timing optimization. Every adjustment measured and verified with back-to-back dyno pulls until the numbers are right.
ATVs, SNOWMOBILES, JET SKIS & MOTORCYCLES
From trail rigs to race-prepped machines. Full builds, big-bore kits, clutch calibration, and suspension work for quads of all sizes.
DIAGNOSTICS & TROUBLESHOOTING
Something's off and you can't figure it out? We've seen it before. Decades of hands-on experience means faster answers and fewer dead ends.
our services
Kennedy Power Sports is a full-service machine shop and performance center specializing in power sports vehicles and automotive dyno tuning. From precision cylinder work to chassis dyno testing up to 5,000 HP, we have the equipment, experience, and obsession with quality to get your machine running at its absolute peak. Dirt bikes, ATVs, side-by-sides, snowmobiles, cars, and trucks: if it has an engine, we can make it better.
Dyno Tuning (Power Sports)
Dirt bikes, ATVs, and side-by-sides. DynoJet 250ix chassis dyno, up to 800 HP.
Whether your engine is bone stock or full race, proper tuning is the only way to guarantee peak performance. Our DynoJet 250ix handles power sports vehicles up to 800 HP. We're an authorized DynoJet tuning center specializing in Power Commander fuel controllers. Carbureted or EFI, we have the capabilities to extract every ounce of horsepower out of your machine.
- $125 — Base Dyno Pull (setup + pulls, HP/torque/air-fuel chart included)
- Starting at $599 — Carburetor Tune (up to 3 hrs tuning, re-jetting, before/after charts)
- $399 — EFI Tune, Pre-configured Map (download map, before/after charts)
- $499 — EFI Tune, Custom Map (programmed for your specific application)
- $179 — Power Commander III/V USB Installation
EFI models require purchase and installation of Power Commander III/V USB for tuning (10% discount with dyno tune). Additional labor may apply for turbocharged, nitrous, or complex secondary air injection systems.
COMING SOON
Dyno Tuning (Automotive)
Cars and trucks. DynoJet 424LC2 all-wheel-drive chassis dyno, up to 5,000 HP.
Our DynoJet 424LC2 all-wheel-drive chassis dyno handles cars and trucks up to 5,000 HP. From stock baseline pulls to full custom tunes on boosted or naturally aspirated setups, this is where serious power gets dialed in. FWD, RWD, and AWD platforms welcome.
- $199 — Baseline Pull (setup + pulls, HP/torque/air-fuel readings)
- Call for Quote — Custom ECU Tune (full custom map, before/after charts)
Vehicle must be in good mechanical condition (no check engine lights, fresh oil, proper coolant levels). Additional setup time may apply for high-horsepower applications.
Cylinder Boring
Precision bore and hone for Cast iron-lined cylinders. Restored to factory-fresh tolerances.
Proper piston-to-cylinder clearance is critical to engine life. Our machine shop measures and evaluates every cylinder to guarantee correct fitment and ring sealing. We bore steel-lined cylinders using our Quickway boring bars (up to 8" bore) and finish with our Sunnen hone, capable of honing nickel plating with diamond stones.
- $149 — Bore and Hone (per cylinder)
- $25 — Hone Only (per cylinder)
- $40 — Additional charge if boring exceeds 2mm
- $45 — Remove and Replace Head Studs
- $45 — Scrap Gaskets Off Cylinder
- $90 — Service Power Valves
Steel-lined cylinders only for boring. If your cylinder has Nikasil plating, see our Nikasil Re-Plating service. Turnaround is typically 2-3 weeks depending on workload.
Cylinder Porting
Hand porting for maximum exhaust and intake flow. Measurable HP gains on the dyno.
Hand porting reshapes your cylinder's port openings for optimal gas exchange, directly translating to measurable horsepower gains on the dyno.
This is precision handwork, not CNC shortcut work. We verify results on our Super Flow bench.
- Starting at $600 — Cylinder Hand Porting (price varies by application and complexity)
Contact us with your make, model, and year for an exact quote. Porting is typically paired with cylinder boring and/or re-plating for a complete top-end package.
our gear
Kennedy Power Sports runs a fully equipped machine shop built for precision engine work and high-performance tuning. From chassis dynos that handle 5,000 HP to diamond-stone honing for nickel-plated cylinders, this is where serious work gets done. Here's what's on the floor.
DynoJet 250ix
Power Sports Chassis Dynamometer
Electro-magnetic load simulation chassis dyno for dirt bikes, ATVs, and side-by-sides. Wide-band air-fuel ratio sensor technology for precision tuning. Authorized DynoJet tuning center.
DynoJet 424LC2
AWD Automotive Chassis Dynamometer
All-wheel-drive chassis dyno for cars and trucks. Handles FWD, RWD, and AWD platforms. From stock baseline pulls to custom tunes on boosted and naturally aspirated setups.
Our Services
- High-speed data acquisition system
- High-speed ETAS Lambda air/fuel analyzers
- 800 HP Eddy current absorber for steady-state testing
- Inertia acceleration dyno runs
- Pressure transducer and thermocouple integration
- Custom testing configurations on request
Baseline Dyno Testing
Find out what your machine is actually making. Every baseline includes one cold run to bring the exhaust system to operating temperature, followed by two hot runs at real-world riding conditions. You leave with a printed dyno chart and our honest assessment of where your power is and where to find more.
$125 · 1 cold run + 2 hot runs
Carbureted Tuning
Jetting, needle position, timing adjustments: we dial in your carbureted setup on the dyno with back-to-back pulls until the air/fuel ratio is spot-on across the entire RPM range. Includes setup and up to 3 hours of testing. Jetting hardware is at customer expense.
Starting at $400
EFI / Fuel Injection Tuning
Full reconfiguration of your ECU map: both fuel and spark timing tables, optimized on the dyno for your specific setup and modifications. Whether it's a Power Commander, Vance & Hines FP4, or a factory ECU flash, we tune to your machine, not a generic map.
$450 · Full ECU map optimization
Cylinder Boring & Honing
Precision boring to the next oversize with a proper crosshatch hone pattern for optimal ring seal. We measure, bore, and verify with the attention to detail that a machine shop should.
$65 per cylinder
Cylinder Porting
Hand-ported intake and exhaust ports matched to your specific build goals. Whether you're looking for peak horsepower or a broader powerband, porting is where the real gains hide on two-stroke and four-stroke engines alike.
Call for pricing
Engine Kits & Custom Builds
Complete engine packages tailored to your goals: big-bore kits, cam upgrades, head work, and full race builds. We also handle custom machining and welding for one-off fabrication needs.
Call for pricing
Our Services
- High-speed data acquisition system
- High-speed ETAS Lambda air/fuel analyzers
- 800 HP Eddy current absorber for steady-state testing
- Inertia acceleration dyno runs
- Pressure transducer and thermocouple integration
- Custom testing configurations on request
Case studies
When you love what you do, some projects become personal. Here are a few builds, including client work and passion projects that we're proud of.
Honda Grom: Small Bike, Serious Gains
Custom dyno tune using a Power Commander 6, optimizing both fuel and ignition maps across the full RPM range. On a platform where every fraction of a horsepower matters, the results speak for themselves.
+19% MORE PEAK POWER
+29% MORE OVER-REV POWER
Verified on our Dynojet Research dynamometer with SAE correction factor. Multiple runs for consistency.
108+ Horsepower at the Wheel
Full dyno session on a liter-class sport bike: baseline pulls, data logging across the RPM range, and a complete picture of where the power lives. Peak output measured at 108.78 HP and 55.04 ft-lbs of torque, confirmed across multiple runs.
108.78 HP PEAK WHEEL HORSEPOWER
55.04 FT-LBS PEAK TORQUE
V-Twin Performance, Dialed In
Cruisers and V-twins respond dramatically to proper tuning. We see Harleys come through with rich factory maps leaving power on the table. A proper dyno session with fuel and timing corrections wakes these bikes up in a way you can feel from the first roll of the throttle.
Quads Are in Our DNA
This is where Kennedy Power Sports began: pulling apart quads and making them faster than everyone else's. Three decades later, we still build ATVs that dominate. Full engine work, porting, jetting, clutch kits, and every modification validated on the dyno.
Yamaha Side-by-Side
Custom Performance Build | Yamaha Side-by-Side
"This Yamaha came in for a basic tune and left as a completely different machine. Full exhaust, ported cylinder, custom EFI map. The owner wanted to keep up with his buddy's RZR. Mission accomplished."
Small bike builD
Custom Small Bike Engine Build
"What started as a simple rebuild turned into a ground-up custom engine project. New bore, ported head, hand-built exhaust. By the time we buttoned it up and strapped it to the dyno, this thing was making power it was never designed to make. Honestly? I almost kept this one for myself."
"Hey, I Think I'll Keep This One for Myself."
Custom Performance Build
Not every build leaves the shop. Some of them are too good. This is one of those. What started as a customer project turned into something Angus couldn't let go of.
Custom engine work from the crank up, ported and polished by hand, dialed in on the dyno until the numbers stopped climbing. When you love what you do this much, sometimes the best advertisement is the one sitting in your own garage. This section exists because Angus doesn't just build engines for a living. He collects them. He races them. He obsesses over them on weekends. That's the difference between a shop that does the work and a shop that lives it.
Every machine that rolls out of Kennedy Power Sports gets the same attention we'd give our own.
Because sometimes, it literally is our own.
Got a project in mind? Let's talk.
Whether it's a baseline dyno pull or a full engine build, the first step is a conversation.
ABOUT ANGUS
Kennedy Powersports was founded in 1990 by Angus Kennedy. The company started due to Angus's love for Quads, Snowmobiles and Jet Skis. Back in the early 1980's there wasn't a lot of performance parts, not to mention many people that Angus could turn to for performance related questions, changes and modifications.
Angus always wanted his stuff to run better than everyone else, so he would pull his apart and try different things. Some worked. Some didn't. Through years of trial, error, and broken parts, he figured out what actually makes power.
Well, as one can imagine, friends started to ask Angus if he could work on theirs. Once Angus agreed, his friends were beating up on their friends! This progression resulted in the beginning of Kennedy Powersports.
"Our business is based on friends, friends of friends, and we'd like to become yours."
Our mission is to provide what Angus didn't have when he started: someone who can answer your questions honestly, recommend the right hardware for your goals, and perform modifications accurately. We take the time to know you and your expectations. That matters to us, because your satisfaction is how we've stayed in business for 35 years.
We know what works and what doesn't through our dynamometer testing programs. Every claim is backed by data. Every build is verified with numbers. No guesses. No hype.
Our business is based on friends, friends of friends, and we'd like to become yours.
Thanks! We'll be in touch soon.
GET IN TOUCH
Ready to talk performance? We're in Rochester Hills, MI and we'd love to hear what you're working on.
Give Us a Call
Kennedy Power Sports
Rochester Hills, MI
Hours:
By Appointment
Call or fill out the form. Angus gets back to most inquiries within a day. If you're not sure whether we can help with your project, just ask. Worst case, we'll point you in the right direction.
Curious how dyno testing actually works?