Bought a used rzr 900 xp in June 2012, 1100 miles and 120 hours, noticed oil usage soon after buying it. Never saw dirt in the intake system so the former owner forgot to tell me about it. And was not truthful when I asked him about it. Rode it for a few months adding a half qt after every day riding. So last week it started running poorly and dieing when cold, seemed to run ok when warm. Pulled spark plugs and found them carbon covered. Bead blasted them and it seemed to run better. Performed a compression test. 90 on the pto side, 200 on the mag side. Pulled all the body work off and checked the valve clearance. The exhaust was .012 and the intake was less than .002. Someone borrowed my thin feeler guage so I do not know what the valve lash was on the intake side. Called Nate at Alba, he told me if it would most likely need new cylinders and pistons and the exhaust valves would be very loose. Decided to tear it down and sure enough Nate was right.
So now the cylinder, head and cams are being shipped to Nate at Alba for new valve guides, valve job and stage 2 cams. Also getting a 96mm big bore kit. Nate kept telling me to split the cases and check the lower end. At first I refused but decided to go ahead and pull the engine from the frame. I split the cases, inspected the crank and bearings and all look good. So I used the service manual to determine the bearings I need and ordered all my parts to reassemble the engine.
Decided to bump up the power a little. I already have an Alba Dobeck fuel controller, bikeman header, and a SLP slip on muffler. I am adding a 96mm big bore kit, stage 2 Alba cams, Alba chain tensioner, and an Alba intake manifold. I guess I will have to figure out what I need to do to get the clutches to match the new power. I have really talked Nate’s ear off on the phone making sue I have a reliable engine when I am done with this project.
