Running rich or lean? Read the plug and tune your carb
A rich or lean symptom means something different at idle than it does at wide open throttle. Garagely walks you through the right circuit for where the symptom actually happens, and keeps a history of every change you make.
Garagely diagnoses a carb symptom by where it happens in the throttle range - idle, transition, top end or a mechanical issue - then points you to the exact field to change and explains why. A plug reading guide backs up the call, and every jetting change is saved so setup history always shows what you actually tried.
What a wrong guess costs you
- A too-lean mixture near the top of the throttle range can detonate or seize a piston, turning a jetting mistake into an engine rebuild.
- Running rich fouls plugs, wastes fuel, and leaves a sooty film that hides other problems underneath it.
- Guessing at a jet change with no record of what you tried means re-diagnosing the same symptom again next month.
- A shop visit for "it doesn't run right" often can't reproduce a symptom that only shows up at three-quarter throttle on the trail.
Myth vs reality
The myth
If it's running rich or lean, just adjust the main jet and hope.
Why people believe it
Most riders were taught one universal fix for a carb problem, so reaching for the same jet every time feels like the safe move.
The reality
The right circuit depends on where in the throttle range the symptom shows up. Idle, the transition through the midrange, and the top end are each controlled by a different part, so the same symptom description can point to completely different fixes.
What to do instead
Match the symptom to its throttle range first, read the plug, then make one change, test-ride it, and log the result before trying the next idea.
Riders like you
After a pipe swap the bike four-strokes and blubbers at the top end, and guessing at the main jet has not fixed it.
The symptom advisor narrows it to the top-end group, suggests a jetting direction with a reason, and the test ride comes back marked Better, but not fixed - one more increment gets it dialed in.
After cleaning the carb the bike bogs off idle, and it is not obvious which of a dozen possible fixes actually applies.
The idle and off-idle group flags the pilot jet and air/fuel screw, the plug reading guide confirms it is running rich, and the change gets logged as Fixed.
Inherited a bike with unknown carb settings and no notes on what a previous owner already tried.
Recording the current jetting gives the setup a real baseline, and every change from that point on is saved with what changed and why.
How guided carb tuning works, step by step
- 1
Record your current jetting
Enter the pilot jet, main jet, needle and clip position, slide and air/fuel screw turns you're running now, so every future change has a baseline to compare against.
- 2
Tap "Something's wrong?"
Tell the app what the bike is doing and it groups the symptom by where it happens: idle and off-idle, the transition through the midrange, top end, or a mechanical issue.
- 3
Pick the exact symptom
Choose from symptoms like bogging off idle, sputtering in the midrange or detonating at the top, and the advice narrows to the circuit that actually controls that part of the throttle.
- 4
Read the advice, and why
Each suggestion names the field to change and explains why, plus a plug reading guide and a lean-condition warning when the symptom could mean a seizure risk.
- 5
Make the change and save it
Enter the exact value you set on the bike, or mark it inspection-only if you checked but changed nothing.
- 6
Test ride and log the result
Report back Fixed, Better, but not fixed, No change or Worse, and the app tells you whether to keep going, repeat the step or revert.
- 7
Apply or revert
A fixed setup becomes your new baseline; a change that made things worse comes with a checklist to set the bike back to its previous values.
Before and after
Without Garagely
- Jetting changes based on trail-side guesses, with no memory of what you already tried.
- A rich or lean symptom gets the same generic fix, whatever throttle range it happens in.
- No way to tell whether the last change actually helped or made it worse.
With Garagely
- Every symptom is matched to its throttle range, with a specific field to change and why.
- Setup history tracks each change and its test-ride result.
- A lean or seizure risk is flagged before you keep riding through it.
What is free, what is Pro
Free
- Guided symptom advisor by throttle range
- Jetting setup history with what changed
- Plug reading guide
- Resumable sessions, works offline after your first connection
Pro
Nothing here needs Pro.
Questions riders ask
Do I need to know my exact jet sizes to start?
No. Enter what you're running now, even approximately, and the advisor still points you to the right field to change.
Does the app tell me exact jet numbers to install?
No, it gives you a direction and a reason - bigger or smaller, richer or leaner - because the exact part depends on your carb and mods. Log what you install so setup history stays accurate.
What if a change makes it worse?
Mark the test ride as Worse and the app gives you a checklist to set the bike back to its previous values, then suggests the opposite direction or a different symptom.
Is carb tuning a Pro feature?
No. Guided carb tuning, the symptom advisor and setup history are free.
Does it work without a connection?
Advice needs a connection the first time you look something up. Your session is saved so you can pick up later, and setup history keeps logging offline.
Related features
Troubleshoot by symptom
Offline fix-it guides plus guided diagnostics online: symptom, likely cause, quick checks and the fix, with safety flagged.
One-tap service log
"I changed the oil today" in a tap. A complete, trustworthy history builds itself as you ride.
Pre-ride checklist
Run a quick tap-to-tick check of tire pressure, spokes, fasteners and controls before every ride. Catch the small thing before it strands you.
Stop guessing at your carburetor
Get symptom-by-symptom jetting guidance, right on the bike.
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