Ron P posted:This looks like a filter to me. Not sure. Best pic I have. Sounds like that's not conclusive proof of engine size. Not brave enough to pull off the head and measure. Hoping it's written on the shroud.
You have something similar to this: http://www.cbperformance.com/product-p/1792.htm
The original pump is replaced with this one and the oil is filtered and returned. This is the cheapest and easiest way to add an external oil filter to the engine. Based on build information your's is most likely a 1915cc motor. I suppose if the previous paid to have it installed it could be the stock 1600 cc motor. Borrow your wife's mirror and head out to the garage. Just don't tell her you're using it.