XT225 FAQ - Engine
My XT is just a bit down on power for my taste, are there any simple modifications I can make to it? I understand it is not a power monster and am not trying to make it one, just simple mods to give it a little more oomph.A:
As far as performance, there are a couple of easy things you can do. First, you can do what is often referred to as the Z1 muffler modification. This comes from the XT225.com forum and you can click here to see the images and detailed instructions on that web site. This modification will open up the exhaust and allow the motor to breathe a little better. Be forewarned that it will make the machine slightly louder. Not excessively so, but slightly. It does not affect the spark arrestor at all, so you will still be USFS legal. It is recommended that you also remove the snorkel on the top of your airbox. This allows more air into the motor.
You will of course have to re-jet your carburetor after making these changes. These are not cast in concrete, but a good starting place is a 130 main jet, 42.5 pilot and then a shim or two under the needle. We have all of these jets (and more for adjustability) and the shims in our jet kit for the XT225. Once you start making adjustments to the carburetor, you will want to remove the brass plug over the fuel mixture screw so you can adjust that as well. This will be a very important adjustment!
I don't have the tools to do the Z1 muffler modification, what other options are available for pipes?
What other options are there for exhaust pipes?A:
You can put a FMF Power Core IV silencer / spark arrestor on your bike. This is considerably louder than stock, but it does have a USFS approved spark arrestor. It also opens up the little dragon and lets it breathe better as well as being lighter than stock as well. I have not installed one on my wife's bike, but have read some really good reviews of it and have had great results with other FMF products.
Why is it that the XT doesn't come with a kickstarter? I see that the hole is in the cases and all, but the rest of the package is missing. Is there a kit to install a kickstarter?A:
Yamaha probably left it off for cost savings, but I really don't know. Yes there is a kit that consists of all the parts you need to install a kickstarter on your machine. The only thing that is not included is the clutch basket holding tool. This really is a fairly simple installation that most folks can do if interested. If you haven't worked on your bike yet, now is a great time to put on your work clothes and get some oil under your nails. Click here to see a really good tutorial with pictures and all so you can see what the project will be like before you start. This will even help once you get started!
Should I follow the stock, recommended break in for a new top-end or is there a better way?A:
Yes there is a better way! Click here to go to mototuneusa (http://www.mototuneusa.com/break_in_secrets.htm) and follow his break-in method. I started doing this a few years ago and have never had a problem. It just makes sense. The factory does us all a disservice recommending a slow break-in. I think the real reason for this comes from their legal department. They want you to ride your new bike cautiously until you get familiar with it. The break-in period is for the new owners brain - not the mechanical parts in the motor.
I was recently watching a documentary showing sport bikes coming off of a Kawasaki assembly line. Every bike was gently warmed up then went right onto a dyno and did a 'full throttle through the gears' dyno run. Then went off to have the oil drained and get crated up. They wouldn't be doing that if there was some harm to be done to the engine without a slow break-in.