Gasket case!
By TMX Archives on 17th Jul 03
YZF450 I currently have as a long-term test bike is, bluntly put, too damn fast - the thing hits like a two-stroke with the awesome power of the 450. THE YAMAHA YZF450 I currently have as a long-term test bike is, bluntly put, too damn fast - the thing hits like a two-stroke with the awesome power of the 450. Even though the bike's in the truck everywhere I go I don't get to ride it as much as I should and while I can continue making excuses for as long as anyone will listen, I just can't avoid the truth any longer - I'm actually scared of it.I've never hurt myself on a bike before but I broke my leg riding this ******d and even though I'm riding it at the big national tracks out here like Glen Helen and Southwick it's still too much for me. Something has got to change. After asking around the pits I found that some of the pros who race these bikes are having the same problem so I don't feel too bad.Taming the beast isn't a hard job, it's just a little time consuming having to fit a flywheel weight and adding thickness to the base gasket - either by getting a specialist 1mm gasket or simply running two stock ones which is what I'm gonna show you how to do.Seeing as I'm still not super-confident when it comes to major mods on a four-banger I thought I'd better get some advice on this deal. So I enlisted the help of Team Mach 1 Yamaha's Christian Kibby (we used him for the 'day in the life of a factory mechanic' a couple of months ago) as he's fully aware of what to do with these things.First of all, make sure you've got a very well-lit working area and a nice clean surface to lay all of the parts on - a towel lifted from a hotel seems to be the tool of choice for most pro-mechanics. You'll also need the owner's manual for torque settings and tightening sequences.Now you need to get access to the parts in question so you need to remove the seat, tank, rad panels, pipe and head-stay.Dump the water and remove any water pipes that are in your way. The carb is easy enough to remove, just loosen the bolts on the clamps and pull it to one side. You may also find it easier if you undo the hot start plunger. Next up the inlet rubber needs to come off and the clutch cable needs disconnecting. Now you should just have the cylinder and head to work on, so take a deep breath and get stuck in - trust me it ain't as bad as it looks...A full step-by-step guide is featured in the August issue of dbr