V-Twin Diagnostics is a Harley-Davidson EFI diagnostic app for 2007–2017 Delphi fuel-injected motorcycles — Sportster, Dyna, Softail, Touring and CVO. It's free to start, and built around tools every Harley rider should have on their phone.
FREE — every rider should have it
★ Smart Service Scheduler — free maintenance reminders so you never miss a service interval
★ 71 DTC trouble codes with plain-English probable causes
★ 119 torque specifications for Twin Cam and Sportster Evo engines plus per-platform chassis
★ Service intervals and bike-specific specs
★ Your garage — register your bike with service records & notes
HOW DIAGNOSIS WORKS — When something's wrong, you skip the $500–$1,000 dealer diagnostic and use a simple symptom-based Q&A: answer plain questions about what your bike is doing and the app correlates those behaviors to the probable component failure — won't start, check engine light on, no spark, stalls when hot, spongy brakes, charging issues and more. Look up Harley trouble codes and diagnostic codes in plain English, read circuit and wiring diagrams for every system, and stay ahead of service with a free maintenance schedule. No Bluetooth adapter, no OBD scanner, no dongle, no scanner tool.
PREMIUM — 3-day free trial, then $9.99/month
★ 12 guided symptom-based diagnostic paths (ignition, fuel, starter, sensors, security, ECM, brakes, wheels, suspension, steering, clutch, leaks/noises)
★ Circuit diagrams for all 12 systems
★ 49 component cards showing the real part behind each probable cause
★ Mechanic's checklist with pass/fail grading + printable PDF
★ Up to 3 garage profiles, service records & notes, diagnostic history
★ Branded PDF diagnostic reports
COVERAGE — 2007–2017 Harley-Davidson with Delphi EFI: Sportster 883/1200, Dyna, Softail, Touring, CVO 110ci. Motor-specific filtering shows only the specs and diagnostics for your exact engine (Twin Cam or Evolution Sportster).
Download free and start with the Smart Service Scheduler — diagnose, not guess.