02 YZ250 Refresh : Sandblasting & Powdercoating (Pictures)

After 10 years, I tought it would be a good idea ro refresh the bike as I had maintenance to perform as well. I decided to start with the frame and swingarm.

I love to learn stuff so I searched around for powdercoating shops so they could refer me to "Self-Serve" sandblasting cabinets. I was lucky enough to get refered to a place about 20km from my place!!!! The place has self-serve cabinets and are only available to referes people ;)

They explained the process and 10 minutes later, I was on my own! It was amazing to see all the Yamaha blue paint being vaporised by the power of sand!!!!!! If you love to try out new things, it a little pleasure to sandblast with professional grade equipment! They came back frequently to provide me tips and tricks but overall I was doing a great job ;p. The end result has a clean and smooth surface, rwady to receive the charges powder particules.

Once the bike frame and swingarm were completely stipped from it's original paint, I went to the Powdercoating facility in the industrial section of the city. They are not too advertised but managed to find it.

I talked to the owner and offered him to do all the the prep work so I could save him time. In fact, I also wanted the lowest price ;) I used the bike bolts to fill all threaded parts of the frame as suggested by the owner. He said that the powder will get in the nut threads and once cooked, it's a problem to get the bolts back in there without "tapping" the threads again.

Also, he kindly provided me with high heat tape to cover the serial # and neoprene plugs for different holes.

He showed me the numerous colors and prices ... I wanted to go back with the Yamaha Blue color but to save $, I opted to join an order of semi-gloss black. The frame would be powdered
and cooked the next day!!!!

Update:
The frame came back and it's gorgeous .  Here are the pictures. 
Note that I kept the original stickers for the looks but I can always recreate the sticker with photoshop and stick it over the existing one if required.  I'll take my decision later ... 

02 YZ250 KickStart assy. mod (Final Solution)

Well, I thought I had posted my last and final modifications to this kickstart assembly modification. After reviewing my blog lately, I saved the draft version but never published it.

After doing the three first steps posted previously to attempt the installation of a counter pin to settle the kickstart lever in place, it was a total waist of time. Just trying to drill a hole through the kickstart shaft resulted in a total failure. The counter pin approach is good in theory but in practice, I finally decided to take another approach.

Ordering the final set of parts :
- I ordered another kickstart assembly shaft from the 2001 YZ250
- I ordered another kickstart oil seal from a 2001 Yz250
- I kept the machined crankcase bought previously and oversized the hole to fit the 2001 shaft (see prev. posts). Machining shop should be able to be right on target to fit the hole to the 2001 shaft.
- I found a used 2001 Kickstart lever with matching splines of the 2001 kickstart shaft in a local scrap yard here in Canada.
- I ordered new crankcase gaskets
- I ordered the 2001 Yz250 bolt to secure the kickstart lever

Installation steps :
With the crankcase dismantled :
- Insert the 2001 YZ250 Shaft and complete assembly
- Install the crankcase gasket
- Insert the machined crankcase that matches the bigger kickstart shaft from the 2001 model
- Insert the oil seal
- Install the new kickstart lever and secure with bolt

Final Result :
In the end, I just swaped in the parts of the 2001 YZ250 in the 2002 modified crankcase and the dirt bike has been working since then. Many kickstarts after, everything is still in place and works like a charm. I will post picture of the end state but for those who have had many questions if this was feasable, well it is!!!

02 YZ250 Polishing and cleaning

Just a couple of pictures (before and after) a little cleaning has been performed. I removed most of the dirt that was kind of burnt in the different component. Some are rusted and will need to be changed (disk bolts for example) but not this year, after all ... it's a dirt bike :)

Below picture is showing left clamp polished with "Blue Magic". Amazing results.

Picture of the wheel and rays also polished.

Rear wheel (Before and After a bit of cleaning)

02 YZ250 - Removing Stickers/Decals

Old stickers were on the bike when I bought it. Some were in bad shape and not being a fan of stickers everywhere, I've decided to remove them all exept the original Yamaha Decals. This can be achieved very quickly without any effort.

The secret is a cheap heatgun!!

Wave the heatgun 2" over sticker for about 30-40 seconds. Use your nail to remove one corner and sticker should peel by itself. If you run into a rough time, heat the sticker a bit more and restart pulling operation. Important to say that sticker will come into one piece instead of multiples pieces when you don't use the heatgun! :)

Here in Canada, www.canadiantire.ca has a jobmate heat gun at 19.00$ CAD. Set it at "low" cause you don't need that much heat to have the sticker removed.

I'll get pictures of the bike once panels are reinstalled.

02 YZ250 - Changing front wheel bearing

After engine has been modified, I've been doing a general checkup on the bike and found out that the front wheel was wobbling left to right (1mm) but it was anoying. I've decided to remove the wheel using the following steps :

Removing the wheel
- Remove plastic brake cover (10mm bolts if I remember correctly)
- Remove the nut that holds the wheel shaft between the forks
- Loosen the nuts that retain the forks to the shaft (4 bolts, 2 on each side)

-

Remove the shaft by carefully hitting on the threaded side (I used a box that was the appropriate dimension to remove the shaft). Careful not to messup the outside and inside threads, they are both valuable.

Removing collars
Remove collars and remember which one goes on what side. The one with a curved end should go on the front disk side.

Removing the oil seal
Using a screwdriver, pry the oil seal out of the wheel. To avoir prying using the wheel's rim, I've dropped a box on it's side and used it as a leverage point. It should pop out right away. You should change the oil seal but I've decided to keep it cause it didn't seem to be damaged.

Removing the bearings
I did not have access to a puller and wanted to change the bearing pretty quickly. Here are the steps :
- find a long flathead screwdriver
- Using your finger, move the bearing to remove so it's unaligned with the center spacer
- From the opposite side of the wheel, aim for the bearing with the flathead and hit with a rubber hammer to get it out.
- 6-7 good hits will get it out of there
- Repeat for remaining bearing

Installing the bearings
- At the dealer, I've decided to take the NKN version of the bearings. They were actually cheaper than OEM and they were sealed (See in the picture the difference between the old and new bearings)
- Add lithium soap grease as described in the service manual (you'll see the blue grease in the picture)
- Insert bearing in the wheel, place a 28mm box over the new bearing and tap with rubber hammer. The bearing should sit pretty easily. Make sure you don't hit on the inner race of the bearing, it will damage the bearing.



Reinstall oil seals
Push oil seals and add lithium soap grease on the lip

Reinstall collars
Pretty straightforward if you remembered where they were at removal

Reinstall the wheel shaft (it is suggested in the manual to grease the shaft). Here, it was greased using the lithium soap grease seen in blue.

02 YZ250 Kickstart assy. mod (Step 3)

Engine has been completely sealed and torqued to appropriate specifications.

Here is the picture without the Crank Lever but with all components.

See how nice the seal and shaft are fitted to (let hope) avoid any oil leaks.

02 YZ250 Kickstart assy. Mod (Step 2)

I finally received the governor bolts and I will reasemble the engine components. Hope I can finish this pretty soon so I can finally give you results. Here's what's left to do :

- Torque Clutch Basket nut
- Pry the Clutch Basket nut lock
- Insert Clutch (pressure plates and friction plates)
- Insert push rod correctly
- Insert Clutch inner cover and torque bolts to appropriate values
- Install new gasket in Clutch cover and torque to appropriate values

Have the kickstart's swivel base drilled to accept a "Roll Pin" instead of a "Spring Pin". It's been suggested by a member of the http://www.thumpertalk.com/ forum and seems to actually better fit the need for this application. Will let you know the outcome.

By the way, estimate date of completion should be close to march 27th, 2010. Stay tuned.