My set-up is like this: I have the main oil bottle (reservoir) with the oil feed line coming from it (plastic tube, similar to fish tank tube) , that line then goes into a syringe (small one, with the plunger removed),it is held into the syringe via a piece of 2cm long rubber fuel hose (the oil pipe is pushed through the rubber fuel hose, nice snug fit)

which in turn fits into the top of the syringe (again, it has to be a snug fit). The syringe (conveniently) has ml measurement marks on it, so I give the reservoir bottle a squeeze, until I have the required amount of oil in the syringe ( depending on the weather, or how far I intend to ride), that oil then makes it's way south through more plastic tube (gravity) towards the rear sprocket, and then oils the chain

No moving parts, all parts easily replaced almost anywhere in the world, cost, considering the years I have had this set-up, nil

Also tried and tested over 35,000 miles so far, with the only mod being the syringe and the copper brake pipe, which has proved to be most reliable, speaks for itself

All this talk of dual feed is OK, but oil will run and spread on it's own, keep it simple and reliable, you don't want to be faffing about with oil, if you can help it
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