Scooter fastener torque record

The problem it solves

Torque figures for these machines are hard to find and, where they exist, disagree between sources. So fasteners get tightened by feel — which is fine on a bodywork screw and is how cylinder heads get distorted, alloy threads get stripped and crankshaft nuts come loose.

We searched for a torque table for these engines and did not find one we would print. What exists is scattered, inconsistent, and often lifted from a different engine entirely. Printing a figure under those conditions would be worse than printing nothing, because somebody would tighten a head bolt to it.

What is genuinely useful is a record. If you have a figure from your own manual, or from a supplier who provided one with a part, write it down along with where it came from — and the next time that fastener comes out, you are not starting from scratch.

The second half of the sheet is about the things that matter regardless of the number: clean threads, the right sequence, and knowing which fasteners on these machines are the ones worth being careful with.

The mistakes this sheet exists to prevent

• Using a torque figure from a different engine because it was the only one findable.
• Torquing a fastener with dirty or damaged threads, which makes the reading meaningless.
• Tightening a multi-bolt joint in a circle rather than a criss-cross sequence.
• Applying a dry-thread figure to an oiled thread, which overtightens substantially.
• Trusting a cheap torque wrench that has never been checked and lives on a shelf clicked up.

How to use it

1. 01Clean the threads before torquing anything. A dirty thread gives a false reading.
2. 02Record where each figure came from, not just the figure.
3. 03Work in the correct sequence on any joint with more than two fasteners.
4. 04Store a click-type torque wrench wound back to its lowest setting.