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Tomos Torque Specifications for A35, A52 and A55 Engine Blocks
Use the torque table below when assembling a Tomos A35, A52 or A55 two-speed automatic engine block and related frame parts. Always tighten with a calibrated torque wrench, not by feel.
Correct tightening torque is important when you build, rebuild or service a Tomos engine. If a fastener is too loose, parts can move, leak or vibrate loose. If it is too tight, you can damage threads, crush sealing surfaces or break small hardware.
Tomos A35 / A52 / A55 Torque Specification Table
The table below is intended for Tomos two-speed automatic engine blocks and related frame hardware. For modified engines, aftermarket parts or worn original parts, always check the part supplier's instructions as well.
| Part | Thread | Nm | kpm | ft-lb |
|---|---|---|---|---|
| Spark plug | M14x1.25 | 18 | 1.84 | 13.28 |
| Cylinder head nut | M7 | 12 | 1.22 | 8.85 |
| Cylinder stud | M7 | 15 | 1.53 | 11.06 |
| Flywheel nut | M10x1 | 30 | 3.06 | 22.13 |
| Clutch 1st gear nut | M10x1 | 25 | 2.55 | 18.44 |
| Sprocket 2nd gear nut | M14x1 | 80 | 8.16 | 59.00 |
| Engine frame bolt | M8x1 | 25 | 2.55 | 18.44 |
| Clutch cover bolt | M6 | 7 | 0.71 | 5.16 |
| Flywheel cover bolt | M6 | 6 | 0.61 | 4.43 |
| Crankcase nut | M6 | 10 | 1.02 | 7.38 |
| Main axle sprocket nut | M22 | 60 | 6.12 | 44.25 |
| Rear swingarm nut | M12x1.25 | 35 | 3.57 | 25.81 |
| Shock absorber bolt | M10 | 25 | 2.55 | 18.44 |
| Steering head nut | M12 | 35 | 3.57 | 25.81 |
| Wheel axle nut | M11x1 or M12x1 | 35 | 3.57 | 25.81 |
How to Use These Tomos Tightening Torques
Start with clean threads, good hardware and a torque wrench that matches the range you need. A small 5-25 Nm torque wrench is useful for many engine fasteners, but it will not cover higher values such as 30, 35, 60 or 80 Nm. For those fasteners, use a larger calibrated torque wrench.
Tighten evenly where a part uses multiple fasteners, especially around the cylinder head, crankcase and covers. Work in stages instead of going straight to final torque on one nut or bolt. This helps the part sit flat and reduces the chance of leaks or distortion.
- Clean threads: dirt, damaged threads or old sealant can change how the fastener tightens.
- Use the correct range: a small torque wrench is best for small Nm values, while higher torque values need a larger tool.
- Tighten in stages: bring multi-bolt parts up evenly instead of fully tightening one side first.
Conversion Notes and Tolerance
Nm is the main value to use. kpm is sometimes also written as mkp, and for quick workshop reference 1 kpm is approximately 10 Nm. The values in this guide have been normalized from the Nm figures so the conversions stay consistent.
Use these tightening torques as reference values with a practical tolerance of about +/- 10%. If a Tomos workshop manual, a performance part manufacturer or a specific product instruction gives a different value for your exact setup, follow that specific instruction.
Why the Nm value should be your main reference
Most modern torque wrenches and workshop instructions use Nm. The kpm and ft-lb columns are useful conversions, but setting your wrench directly to Nm reduces confusion and keeps the job more consistent.
Back to topTorque Wrench and Assembly Tips
Torque values only help when the parts are prepared properly. Before final assembly, check that the hardware matches the part, the threads are not stretched or damaged, and the mating surfaces are clean.
After the first heat cycle or short test ride, inspect important parts for leaks, movement or loose hardware. Do not simply over-tighten a part to stop a leak. Find the real cause, such as a damaged gasket, uneven surface, worn thread or incorrect part fitment.
Back to topFAQ: Tomos Torque Settings
Which torque wrench do I need for a Tomos engine block?
For most small engine fasteners, a 5-25 Nm torque wrench is very useful. You also need a larger torque wrench for higher values such as 30, 35, 60 and 80 Nm.
Do these values apply to Tomos A35, A52 and A55 engines?
This overview is intended for Tomos A35, A52 and A55 two-speed automatic engine-block and frame assembly. Always check your exact engine version and any aftermarket part instructions.
Should I set my torque wrench to Nm, kpm or ft-lb?
Set the wrench to Nm when possible. The kpm and ft-lb values are included as conversions for tools or manuals that use other units.
Can I tighten Tomos engine parts by feel?
You can do basic disassembly by feel, but final assembly should be done with a torque wrench. This is especially important for the cylinder head, crankcase, flywheel, clutch and axle hardware.
