2005 YZ250 Build

richardWhen Richard isn’t working at GearHead, he spends most of his free time on the seat of an mx bike or next to one with a wrench in his hand. In this this post, Richard will keep us updated on his most recent project, a 2005 YZ250, that he is fixing up to use as a track/race bike.

UPDATE 4: The Final Product
For the finished product I received and put on the rest of the parts. I added an oversized Braking Brake rotor which helps the bike stop on a dime! As for the pipe I threw a FMF Fatty on there, with the factory finish of course. I honestly couldn’t believe how big of a difference this made for the bike. On a 4 stroke adding a pipe just makes a little change in the performance but on this 2 stroke it made the engine act in a total different way. It completely changed where the power band hit. With the stock pipe the power band hit hard on the bottom end and signed off towards the top. The Fatty pipe changes the power band to pull pretty evenly. And I added the infamous Motoseat to help me stay on this wild beast! There is no better way to update the look of an 11 year old bike than to put 2016 plastics on it, so I called the guys up at gearhead.com to get the conversion kit for it. As for the graphics kit I emailed Black Diamond MX and told them a general idea of what I wanted and they absolutely hit it out of the park. They made any changes I wanted to the graphics kit and then sent them out to me. The graphics are made of quality material and are the best graphics I have ever put on a bike. I am really excited with how the bike turned out! It runs great and looks pretty great too.
GearHead Shopping List



filterMy first order of parts came in from Gearhead.com! I ordered all the stuff to get the bike in decent riding condition. The first thing I ordered with Gearhead was a uni air filter. I love their inner/outer filter design! The outside filter is supposed to grab the bigger stuff and the inner filter grabs the smaller things that usually cause engine damage. Use one of these filters and they will help you sleep better at night knowing that your engine is breathing the cleanest air it possibly can!

yz250 new suspensionI threw on some clean Tag grips as well. They are pretty similar to bike_2ProTaper’s pillow tops but they help cushion your hands a little more. I figure this will help with the 2-stroke vibration.
I robbed a works connection holeshot device and a set of Sunline levers from one of my other bikes. I used to go through levers all the time. One spring I snapped 3 front brake levers in a month. Then I got these Sunline levers. They flex forward like the ASV levers but they also pivot up and down so almost no matter how you impact them they just move out of the way. Now whenever I go down in a corner all I have to do is pick the bike back up and keep shredding! The best part is if they do break, they come with a warranty so all you have to do is call Sunline up and they will get you taken care of!

The last thing on my order from Gearhead was a set of Pirelli Extra X tires. I’ve tried out a lot of different tires since I’ve started riding and these are by far my favorite tires! The tire design makes it so the side nobs don’t come off prematurely like dunlops tires do. They must be putting some kind of magic in the tires at Pirelli because the tread doesn’t seem to round off near as fast as other tires. All these things make it so the traction is great and stays that way for at least twice as long as most other tires out there!

As for my suspension I decided I would just upgrade by getting a used suspension off a newer bike and sending that to rg3 for them to trick out! This way I will have the new SSS forks and a heavier duty rear shock! I checked around and found someone who had a suspension off a 2008 yz450f and they also had some spiffy wheels that I was able to snag from them for pretty cheap so why not kill two birds with one stone right?




The whole drive home I was wondering what could be wrong with the suspension so I decided to dive into that one first. Clearly the problem
Stripped. No bueno.
with the rear suspension was simply that it had been leaking for over ten years and had no more fluid left in it. The front suspension is a little different though. It wasn’t leaking at all but I could hear the springs clapping inside the tubes. I decided to take the forks apart and noticed that the bottom of the cartridges were stripped out so the bottom fork tubes weren’t even bolted on. The only thing holding my front tire on was a snap ring! At this point I knew I was going to have to fork out some serious money for this suspension (pun not intended).

While test riding the bike I also noticed that the pipe was pretty smashed up and the tip of the foot peg on the right side was somehow sheared off! I can’t even imagine how that would have happened. While checking the

yz250 air filter
Crappy Condition of Air Filter

wheel bearings to see what condition they were in I noticed that the rear rim had a nice crack in it! Definitely going to have to get a set of those.

When I took the seat off to check the air filter my heart sunk. The air filter was falling apart and didn’t look like it had ever had any oil put on it! At that point I had to call it a day. I just couldn’t handle thinking about how much torture this poor yz had received over the past 10 years.
After a night full of weeping in the fetal position and a handful of nightmares about engines seizing, I decided to crack open the engine and see the damage. To my utmost surprise everything looked really good! I guess the bike just hadn’t been ridden since the air filter started to fall apart.
Now that I had gone through a large part of the bike I decided to give GearHead a call and get some parts on their way!



I have always had a 4 stroke bike. I first started riding in 2007 on a 2005 yz250crf250r. Since then I have had my fair share of 250f’s and 450’s. I soon realized that since I wasn’t fortunate enough to be born in this celestial sport that I completely missed the whole 2 stroke stage. This definitely puts me at a disadvantage since 2 strokes take A LOT more work to get around a track quickly! So I decided I should figure out what those massive pipes wrapped around the frame are all about.

2005 Yamaha yz250Unfortunately, finding a race ready 2 stroke on the budget of a married
college student starting a family proved to be difficult if not impossible. This is exactly where Gearhead.com comes in to save the day! But we will get back to that a little later. First let me introduce to you the bike I ended up purchasing.
After searching all winter for an off season deal, I ended up purchasing a used 2005 Yamaha yz250. As you can see in the photos above of me bringing it home, it came with a Pro Moto Billet kickstand, Cycra hand guards and a FMF silencer (can’t really see in the pic sorry), but other than that it’s basically stock. I knew right off, the hand guards and kickstand will need to go since this is going to be set up for the track. I was pretty excited to see the FMF silencer because I have always been a FMF fan. While test riding the bike I noticed that everything on the bike felt nice and tight except the suspension. Something was definitely wrong there but I couldn’t put my finger on what exactly it was. I decided that I would take the risk on the suspension and get the bike anyways, I mean what else is a college kid going to do when he gets a whiff of that premix?
I was super pumped to get the bike home and tear into it and see what goodies I could get from Gearhead.com.
In the next post I’ll take a look at what the issue is with the suspension and look at some bolt on aftermarket parts.
Interested in a free GearHead T-Shirt? Submit a video or write up of a repair you’ve done recently and if it’s featured in our blog, we’ll send you some GearHead swag! Email mdyer @ gearhead.com for more details.

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