On an oil change once, I didn't replace the copper washer on the frame bolt.

After a week or so, I noticed a rather large pool of oil under my bike at the petrol station, and the bolt had come loose and worked its way out.

I have no idea how long I'd ridden with it leaking oil, so my mate took a trip to the Yamaha garage, borrowed me a new bolt and a litre of oil and I limped home, nursing it carefully.

Changed the oil and haven't had any problems.
Fingers crossed, but that was over 20,000 miles ago!

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Bike: 2013 XT660Z, TKC70 tyres

Mods:
Barkbusters, Scottoiler, DIY Tail Mod, DNA Stage 3, Power Commander V & O2 Eliminator, Exan X-Black Stainless exhaust, Tool tube, Ohlins linear front fork springs, Nitron rear shock, JT front and Supersprox rear sprockets, D.I.D. VX 520 chain, Adventure Spec bashplate, DIY USB Outlet, DIY chain guide, Kev's Throttle mod

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