Does anyone know if there is another Suzuki pump that will fit the GS and offer uprated oil flow. I'm building a hybrid engine, using a later set of crankcases and oil pan, but want to use a larger oil cooler compared to the standard GS unit. something like a 10 or 13 row or such. and as i know one weak point of the GS is oil flow to the head, and the balance shaft bearings can go. I figured if there was some way to improve the flow, and the quantity of the oil and keep it at a nice temp, that it will help on the long distance runs I'm building this motor for.

I don't know of any, and I don't have any experience upgrading stock systems. But here's something to think about - a friend of mine burnt up a few heads on his Honda CB360 due to lack of oil flow. So he ended up adding an electronic oil pump that specifically oiled the top end. I never asked for all the details, but hopefully that gets you started....

I have some experience using uprated parts on small honda engines (passport type for the US forum members) i built a 110cc motor using a TRX90 oil pump compared to the standard honda 90 type as it offers a far higher flow.. and you open the oil ways using a post drill by a extra mm so it improves flow to the head and cam.

I was hoping a similar upgrade could be done using a Suzuki pump and some mild machine work to improve oil flow to the head and more volume using the cooler to hold say and extra 1/3 to 1/2 litre and improving cooling.