I have experienced the hard way about the issue with the breather hose. Luckily it seems like most of the sand is gone by a couple of oil changes, and no more sand will enter again with the re-routing mod. At least not by that passage.. What I have accomplished by sand riding so far: Sand in engine Seized two chains Eaten up sprockets Rear bearing worn out Destroyed mud flap Chewed up one side of the smaller alu frame (next to chain) And that's after 2 days at Pismo beach. My new modifications to make the bike last longer: Scotts steel filter Re-routing of the breather hose Womens stockings on the small intakes on the sidepanels Grease on the air filter contact surface Filled the small holes in the airbox Extra link in chain to get the wheel as far back as possible PCV pipe on the left side of alu-steel frame for stop the chain from chewing it up Use GREASE instead of teflon on the chain. I have no clue why people recommend teflon lube, at least I did never manage to use it without seizing the chain. I did avoid the grinding paste problem, but rather that than bent shaft in the gearbox. The sprockets got chewed up anyways.. Any comments on more mods to add? I dunno if its possible to save the rear bearings though, they get a pretty good beating with the 10 paddle. My jetting is also a bit rich, but I want to stay safe considering the hot sand dunes. Current setup: Pilot 54, Starter 70, Needle: Dynojet, middle click, Main: 170, Fuel screw 3 + 1/4 out. Pipe: spark arrestor of some sort, stock header. The ride is a YZ450 2005. Stock airbox as well Comments on the jetting is appreciated. I feel I still have to try some other setups too before posting it on the database. I found it a bit strange when it has this huge demand for rich mix at idle. With this setup it only starts with choke, but on the first or second kick. The carb (not completely sure about the specific model) has the fuel screw available under the floater chamber stock, so no need for the R&D lid. Thinking about it now, the fuel screw setup would make sense if its leaning out when turning out, but I'm pretty sure that its the opposite way.