Not dreaming - I did put engine oil in. I stopped using fork oil years ago. I think it is a giant con and if you want to use a specific weight oil, you can mix say a 5-40 and 10-40 multigrade "synthetic" oil, to get the right weight. So if you want 7.5W, just mix 5-40 & 10-40 50/50. I have an 2001 triumph bonneville that I put 15-40 oil in back in 2002. No problems, no seal failures and it fixed the topping out issue with the stock 10W fork oil Back in the 70's, I had a BSA, Triumph and Honda bikes. The BSA & Triumph recommended engine oil, the Honda automatic transmission fluid (ATF). Engine oil is fine, specially car oil, it has all kinds of friction lowering additives in it (ATF doesn't), is more thermally stable than fork oil, which I think smells like lathe cutting fluid. The viscosity is more stable and reliable. I have seen charts that measure viscosity of different brands of fork oil and the viscosity is quite variable between them... Here's one transmoto.com.au/comparative-oil-weights-table/ Ultimately, the choice is yours, of course. The viscosity will vary based on what aftermarket stuff you may or may not have in your forks. For stock forks after trying 10W (too stiff) and 5W (a little bouncy) in my bike, I recommend 7.5W Just checked my maintenance log and I used 5-40 Shell Rotella synthetic. Good luck - watch your hands if the fork is hard to get out of the triple clamps

Can you tell me what weight a 10w40 oil is please?

This video will go viral for all the wrong reasons #engineforkoil

😄😄😄 Sorry, I don't usually use emojis.

Because???