I've recently installed one underneath the seat attached to frame on the right hand side about level with the exhaust mounts. Then fed the oil tube across the bike down the left hand side of the air box and next to the spring then used the holes in the swing arm to feed it to the back without being on show too much.

I've recently had to adjust mine as I was getting loads of over flow and it spraying off. It was dripping off every surface, must've knocked it once or twice when adjusting its position and set the flow to max. One of the reasons I like where I've put is that the dial is hidden underneath part of the frame so won't be knocked now its in place.

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Yamaha XT660X '08' Blue | DNA Stage 1 | MTC 2 into 1 Carbon Oval | OTR Tail Tidy | Engine Painted Black |