Free printableComplete packsTSP-PK-02FLAGSHIP
The GY6 Workshop Pack
Identification, transmission measurement, service records and the two diagnostic chains that cover most no-start faults. Seven sheets.
Layout preview of page one. The PDF itself is typeset text, not an image.
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21 pages. No account, no sign-up, no newsletter. Print it, copy it, hand it to somebody else.
TSP-PK-02 · version v1.0 · September 2026. Opens in your browser's PDF viewer, where you can print directly.
The sheets inside this pack
Every one is also available on its own, free. The pack exists so you can print once rather than 7 times.
- 01GY6 engine identification chart and worksheetTSP-ID-03
- 02Short case or long case? How to tell, and why it decides everythingTSP-ID-04
- 03GY6 belt size chart and measuring sheetTSP-ME-02
- 04Variator roller size chart and measuring sheetTSP-ME-03
- 05CVT service record for a GY6 or Chinese scooterTSP-MA-05
- 06Chinese scooter won't start: diagnostic chartTSP-TS-01
- 07GY6 no spark diagnostic chartTSP-TS-02
The problem it solves
Working on one of these engines means answering the same four questions over and over — what is it, what size are the parts in it, what has been done to it, and why will it not run. Those answers live in four different places, and on a machine with no manual and no history they usually live nowhere at all.
GY6 is a family, not a specification. The name covers several displacements, two crankcase lengths, air and liquid cooling, and fifteen years of component changes made by different factories. Which is why “it's a GY6” is where most people stop and why it is not enough to order a part.
This pack is built around the things that actually distinguish one from another and can be established with a tape measure and a torch: the code stamped on the crankcase, the distance from the crank to the axle, the belt and roller dimensions, and what the plug looks like after a run.
It closes with the two diagnostic chains — will not start, and no spark — because those are the faults where the most money gets wasted on parts that were never broken. Both end at observations rather than at components, which is the only honest way to write a diagnostic for a machine you cannot see.
The mistakes this sheet exists to prevent
- Treating GY6 as a specification. It is a family covering several quite different engines.
- Ordering a belt by displacement rather than by case length.
- Replacing the CDI first when there is no spark. It is the most expensive part in the circuit and among the least likely to have failed.
- Servicing the transmission without recording what went in, so the next service starts from nothing again.
- Reading the crankcase code as containing a zero where there is a Q, then concluding the engine is unrecorded.
Who it is for
- Anyone who works on their own GY6 or Chinese scooter engine
- Owners of a machine with no manual, no history and a badge that leads nowhere
- Anyone diagnosing a no-start before buying parts on somebody's guess
What is on it
- Engine identification by measurement and casting marks, with the code decoded
- Short case versus long case, and what that answer decides downstream
- Belt and roller measurement with true-size scales
- A CVT service record that produces your own wear rates
- The will-not-start and no-spark diagnostic chains
How to use it
- 01Start with the identification sheet, even if you think you know what you have.
- 02Do the case length measurement before ordering anything that runs between the crank and the axle.
- 03Check the calibration rule on any sheet before measuring against a printed scale.
- 04Keep the CVT record with the machine and fill it in every time it is opened.
Use it with the registry
Other sheets you may want
- GY6 engine identification chart and worksheetThe measurements and observations that tell you which engine you have when the label is gone — recorded in the order a parts supplier will ask for them.
- Short case or long case? How to tell, and why it decides everythingOne measurement and one count decide which drive belt, which wheel and which brake your engine takes. Take them before you shop, not after.
- GY6 belt size chart and measuring sheetHow to read the three numbers printed on a scooter drive belt, how to measure a belt that has no readable markings left, and a record sheet for the one you have.
Free to print, copy, and share — including in forums, clubs and workshops. If you find a mistake on this sheet, tell us and it gets corrected. Quote TSP-PK-02 and the version so we know exactly which sheet you mean. All printables.