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Rebuild 2003 WR250F


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Hey Guys

 

Thought I would start a rebuild thread of my new to me 2003 WR250F

It's my first offroad bike so I'm learning as I go.

 

What the bike looked like before I bought, the previous owner did absolutely nothing to keep it in good shape hence the reason I have decided to rebuild it.

2003WR250F1_zps8f2e9dda.jpg

 

2003WR250F2_zps006d6fa7.jpg

Edited by BassDude
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The 'before' pics don't look that bad...I'll be watching your progress, I just bought an 03 back in June and it could use some sprucing up. You going to rebuild the motor too?

 

It looks like I might need to fit new valves so when I pull the head off I'll check the piston and rings and change them if needed. Just have to take it slow as I don't have a whole lot of cash to throw at the bike right now.

I'm busy with the suspension linkage bearings at the moment and luckily they look OK, just need to clean and repack them.

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I think you are off to a good start.  I like that you are checking things as you go and just not replacing everything.  My WR and DRZ had all of the same valve shim sizes from the factory.  I'm guessing if all of your intake shims are the same and exhaust shims are the same, that the previous owner never had any problems with valve clearance.  That will give you an idea of what kind of condition the head is in.  Head work is expensive, especially for an older bike.  The previous owner of my 01 didn't even know what valve clearance was when I ask him.

A lot of people install a higher compression piston from a new model for a little more power.  It is not as expensive as a big bore kit.  I don't know how much of a power increase it would make since I've never done it, but if you are going to replace the rings.

That new gas tank is going to look really shiny next to the old plastic.  But if money is short, I would make sure the mechanical upgrades are done first.  Plastics and graphics can be changed anytime.

 

This is the thread about the work I did and my experience I had last year with  01 WR250F  https://www.thumpertalk.com/topic/975638-suggestions-for-a-new-to-me-wr250f/

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I think you are off to a good start.  I like that you are checking things as you go and just not replacing everything.  My WR and DRZ had all of the same valve shim sizes from the factory.  I'm guessing if all of your intake shims are the same and exhaust shims are the same, that the previous owner never had any problems with valve clearance.  That will give you an idea of what kind of condition the head is in.  Head work is expensive, especially for an older bike.  The previous owner of my 01 didn't even know what valve clearance was when I ask him.

A lot of people install a higher compression piston from a new model for a little more power.  It is not as expensive as a big bore kit.  I don't know how much of a power increase it would make since I've never done it, but if you are going to replace the rings.

That new gas tank is going to look really shiny next to the old plastic.  But if money is short, I would make sure the mechanical upgrades are done first.  Plastics and graphics can be changed anytime.

 

This is the thread about the work I did and my experience I had last year with  01 WR250F  https://www.thumpertalk.com/topic/975638-suggestions-for-a-new-to-me-wr250f/

 

Thanks toadl. Nice job on your 01

 

My shims were all still original factory spec, I have re-shimed the exhausts down 1 size to get them back in spec but my centre intake was closed up completely, I installed a 170 from a 181 and I still don't have clearance, going to drop in a 160 and see if that sorts it out and then watch the clearances very closely. Advice from members here is to not take a chance and rather get the head sorted now, but I've spoken to a Yamaha mechanic and a mechanic that maintains the local Yamaha racing teams bikes and they both said that I can re-shim it and then just keep a close eye on the clearance, if it moves quickly then I have to do the head with new valves. They say they regularly shim bikes all the way down to 140 shims :excuseme:

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Pulled out the swing arm and linkage bearings today and I'm happy to say that they are all good ?

Just need to replace 4 bearing seals as I damaged them taking them out :wacko:

 

Next up - the rear shock, my rubber bump stop is falling apart so I need to replace that, but do you think I can find one locally :mad: looks like that will be coming from the US as well. I can't buy a bump stop from Yamaha you have to buy the whole damn shock.

 

Can't believe how long it is taking to clean 10 years worth of grime off everything.

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 I've spoken to a Yamaha mechanic and a mechanic that maintains the local Yamaha racing teams bikes and they both said that I can re-shim it and then just keep a close eye on the clearance, if it moves quickly then I have to do the head with new valves. They say they regularly shim bikes all the way down to 140 shims :excuseme:

I've heard the same advice given here that you got from your mechanic.  It's good advice.  Following every one's advice, and you'll end up spending as much money as an almost new bike.

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I've heard the same advice given here that you got from your mechanic.  It's good advice.  Following every one's advice, and you'll end up spending as much money as an almost new bike.

 

Thanks toadl, spoke to a third Yamaha mechanic today from a different dealer and he told me the same thing.

 

Put a 160 shim in today and now my centre intake is within specs ?

 

Ordered a new Cam chain today, should be here by tomorrow.

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After sorting out my shims tonight I got stuck into my rear shock, the rubber bump stop has disintegrated so I pulled it all apart and is now ready for cleaning and reassembly. Will pick up a new bump stop tomorrow along with new seals and then have my first go at rebuilding a rear shock with new oil and seals, once it's all done I'll take it to have the nitrogen recharged.

 

New seals for the swing arm linkage should arrive tomorrow as well.

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I curious how much it cost to have the shock charged with Nitrogen.  I've been told a good welding shop could charge it.

 

I've also been thinking about your paint job.  I've been wanting to paint my frame, but I don't know if I want to put the money into powder coating it.  How well do you think your paint job will hold up?  Have you painted a motorcycle frame before?  Motorcycle boots will be very hard on the paint.  Maybe look at some frame guards.  I like the plastic ones.

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I curious how much it cost to have the shock charged with Nitrogen. I've been told a good welding shop could charge it.

I hear of a lot of tire places advertising using nitrogen to fill tires. For such a small amount they might not even make you pay.

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I curious how much it cost to have the shock charged with Nitrogen.  I've been told a good welding shop could charge it.

 

I've also been thinking about your paint job.  I've been wanting to paint my frame, but I don't know if I want to put the money into powder coating it.  How well do you think your paint job will hold up?  Have you painted a motorcycle frame before?  Motorcycle boots will be very hard on the paint.  Maybe look at some frame guards.  I like the plastic ones.

 

I've found a guy fairly near me that rebuilds shocks and forks for most of the shops in the area, I managed to get the rubber bump stop from him as well, he said he will charge me $10 to fill it.

 

Guy I work with said he had his old YZ250F frame powder coated and said that after about a year he had a big piece of paint flake off because there was rust building underneath it that he never knew was there. The rust started with a small scratch and then moisture got underneath it.

I figured that spray paint will be a little softer and easier to scuff with boots and so on, but a quick sand and touch up with an airbrush will keep it looking good, something I can't do if it is powder coated.

I've never resprayed a bike frame before, but I have sprayed a complete boat and outboard engines with good success. The key is that you need to use an etch primer and then a 2 pack paint.

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I hear of a lot of tire places advertising using nitrogen to fill tires. For such a small amount they might not even make you pay.

 

You can't use a normal tyre pump at a garage to fill a shock cylinder, your chances of blowing the air bladder are too great and you can't get the pressure accurate enough.

They use a special regulator valve to fill the bladder to the correct pressure and then it holds the pressure on the connection while the valve is being released. Takes all of about 1 second to loose all 200psi out of that bladder, it's tiny

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All the shock parts cleaned up and ready to go back together along with the new rubber bump stop

 

2003WR250F8_zps601e8b88.jpg

 

The shaft now ready to go back into the housing

2003WR250F10_zps7ad3ef6c.jpg

 

My shock spring looked pretty damn ugly, so it's getting repainted, here I have just painted on paint stripper. This stuff is nasty, was wearing latex gloves and it burnt me right through them, we won't even talk about the little splatters that landed on my arms :eek:

2003WR250F9_zps8b9eb719.jpg

 

Will take pics of the freshly painted spring mounted on the shock tomorrow once it's dry enough to work with

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OK rear shock all done except for the nitrogen fill which I will get done later this week.

2003WR250F11_zps82f3a164.jpg

 

Pulled my forks apart today to change seals, but then found that the bushings are too badly worn so need to get a new set and then also noticed that the dingbat at the store sold me the wrong oil seals and this dingbat didn't notice :rant:

2003WR250F12_zps530d10ed.jpg

 

Then decided to pull my rear sprocket and brake disk off to make cleaning the hub easier and while I was there thought I would shiny up those parts too.

First 2 pics show one side cleaned and the other still dirty.

2003WR250F13_zps4bafd233.jpg

 

2003WR250F14_zps8b3a79f8.jpg

 

Almost like bought ones ?

2003WR250F15_zps4073bd32.jpg

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Got my rear shock filled with Nitrogen today and he did it for free too :D

While I was there he did all the clicker and spring settings to factory spec for me as well so it's ready to just bolt in.

 

Tonight I climbed into the exhaust pipe with a wire brush to get rid of all the rust and pulled the packing out of the can to clean it up and then repack it. Will take some pics tomorrow

 

Also had to order my fork bushing kit from Ebay as the agents had no stock, so I can't rebuild my forks for the next few weeks while I wait on the postal service. :(

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