The RM00018 is a brand new ignition source coil supplied for the repair of the stator on the Yamaha YZ 250 of 1987 and 1988. The source coil is the winding inside the stator assembly that generates the charge the ignition system relies on, and it is commonly the component that fails while the rest of the stator plate remains serviceable. Fitting a new source coil rather than a complete stator keeps the original backing plate, the timing reference and the remaining windings exactly where they were.
This coil is wound with the highest grade copper on the highest grade lamination materials, and its insulation is resistant to 200 degrees celsius so it survives the heat inside a two-stroke ignition cover. It works with all other OEM parts on the ignition side, and all product shipped are tested. Source coils in this specification are often unavailable from the OEM manufacture, which makes a quality aftermarket replacement the practical route for keeping an early YZ 250 running.
Key Features
- Brand new ignition source coil for repairing your stator
- Highest grade lamination materials
- Highest grade copper windings
- Windings resistant to 200 degrees celsius
- Works with all other OEM parts
- All product shipped are tested
- Often unavailable from the OEM manufacture
Technical Specs
| Specification |
Detail |
| Fixation holes centre to centre |
48 mm |
| Big coil resistance |
Between each leg 350 ohms +/-20% |
| Small coil resistance |
Between each leg 50 ohms +/-20% |
| Temperature rating |
200 degrees celsius |
| Part number |
RM00018 |
Vehicle Fitment Guide
| Make & Model |
Years |
| Yamaha YZ 250 |
1987-1988 |
OEM Part Number Cross Reference
Aftermarket replacement. OEM part numbers are listed for reference only.
| Part Number |
Manufacturer / Brand |
| 2HH-85510-K0-00 |
Yamaha |
| 2VM-85510-K0-00 |
Yamaha |
Frequently Asked Questions
Will this source coil fit without modifying my stator?
Yes. The fixation holes are 48 mm centre to centre, matching the original, and the coil is designed to mount to the existing stator plate on the 1987 and 1988 YZ 250. No drilling, cutting or rewiring of the backing plate is required.
What is included?
The ignition source coil itself, ready to fit to your existing stator. The backing plate, flywheel and the remaining stator windings are not part of this listing and are re-used from your original assembly.
How can I tell that my source coil has failed?
The usual signs are no spark at all, a weak or intermittent spark, a machine that refuses to restart once hot, or a misfire that appears under load. A meter gives the definitive answer: the big coil should read approximately 350 ohms between each leg and the small coil approximately 50 ohms between each leg, both within plus or minus 20 percent. An open circuit, a short, or a reading well outside those figures points to a failed coil.
Why replace the source coil rather than the complete stator?
On these machines the source coil carries the heaviest thermal and electrical load and generally gives up while the rest of the stator is still sound. Replacing only the coil retains your original backing plate and timing reference, and complete stators for these two model years are frequently no longer offered new by the OEM.
Dispatched from the UK · 12-month warranty · Fitment support from our technical team
