1995 Yamaha yz250 resto (Attention Engine Gurus!)

FWYT
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3558
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5/25/2014
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San Diego, CA, USA
1/24/2018 7:33pm
Zach_K wrote:
I’m definitely finishing it. I’m probably going to update the suspension and possibly the swingarm (due to it being eaten a bit). I like the Emig...
I’m definitely finishing it. I’m probably going to update the suspension and possibly the swingarm (due to it being eaten a bit). I like the Emig look and Bradshaw. I can find white and black plastics al say but blue is almost impossible. The silencer is definitely not made for this bike. It was getting fabbed.
Zach_K
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164
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6/13/2017
Location
Sneads Ferry, NC, USA
1/25/2018 7:57am Edited Date/Time 1/25/2018 8:05am
Having a hell of a time removing the needle valve. It hasn't budge at all and I messed it. The carb has seen better days. the float bowl, even after soaking is mineral spirts, is still gunked up.


Will this be a good replacement? From a little research on thumpertalk this is what people are using and helps this engine run even better than before, especially on the bottom end.
https://rover.ebay.com/rover/0/0/0?mpre=https%3A%2F%2Fwww.ebay.com%2Ful…


Zach_K
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Sneads Ferry, NC, USA
1/25/2018 9:03pm Edited Date/Time 1/26/2018 7:37am
Got a little more work in last night. This lug ain't budgin. Soaking it in pb so hopefully it comes loose.


Final parts to clean up before the engine is ready to send off for rebuild!


Almost there!


The expansion chamber is looking super fine after lots of elbow grease and some new chemicals.


This last bit is a pain, but its coming along. Then ill polish it up with mothers then take a torch to it!


This new solvent I picked up is the bees knees. This after light scrubbing just to test it.


This is how they looked


The new chemicals. Lime-a-way attacks carbon and rust. I sprayed a bit on the power valve and its cleaning up nicely. It was originally chard black and reeked of carbon


My work area is a mess though. I'm prepping the KTM for a race this weekend so crap is everywhere


lcgordon711
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Denver, CO, USA
1/26/2018 7:12am
Be sure that carb is real not just a knock off. Seems a bit cheap for a new real one. I could be wrong

The Shop

FWYT
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San Diego, CA, USA
1/26/2018 8:51am
Nice going, Zach!!
Zach_K
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164
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Location
Sneads Ferry, NC, USA
1/27/2018 6:28pm Edited Date/Time 1/27/2018 6:47pm
Found a 98 bottom end with a good crank! Contemplating if I want to keep or sel because I don’t think it has a long rod



And got a 04 yz250f parts bike to steal the shock, forks, brakes and swingarm. If anybody needs this frame let me know!



Hondas4Life3
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Spring Hill, KS, USA
1/27/2018 8:02pm Edited Date/Time 1/27/2018 8:02pm
Either way I would replace the crank seals. All crank seals have a service life which is normally shorter than the bearings. The seals fail and then the bearings do. Long rod all the way why spend all this money to make it stock again?? Long rod!
Zach_K
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Sneads Ferry, NC, USA
1/27/2018 8:59pm
Either way I would replace the crank seals. All crank seals have a service life which is normally shorter than the bearings. The seals fail and...
Either way I would replace the crank seals. All crank seals have a service life which is normally shorter than the bearings. The seals fail and then the bearings do. Long rod all the way why spend all this money to make it stock again?? Long rod!
I got the bottom end and frame for a great price that can easily be recovered! May list on on eBay and the proceeds will go towards the build
scooter5002
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Nanton Alberta, CA
1/28/2018 6:33am
98 is a long rod motor, right from the factory. If memory serves, when the ‘96 new gen bike came out, the cases were made to incorporate 5 more mil height, right in the casting.
23champ
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2/6/2017
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Troy, KS, USA
1/28/2018 8:25am
Lime Away Gel on the exhaust pipe will take the rust right off. Cake the gel on, let it sit for 10-15min, hit it with a pressure washer.
Gotta be the gel, the spray doesn’t work as good.
Zach_K
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6/13/2017
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Sneads Ferry, NC, USA
1/28/2018 11:07am
98 is a long rod motor, right from the factory. If memory serves, when the ‘96 new gen bike came out, the cases were made to...
98 is a long rod motor, right from the factory. If memory serves, when the ‘96 new gen bike came out, the cases were made to incorporate 5 more mil height, right in the casting.
Hmm...looking at the parts fiche the 95 and 98 have the same part #s for rods but different for the cases?
Zach_K
Posts
164
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6/13/2017
Location
Sneads Ferry, NC, USA
1/29/2018 11:22am
Sunday I got a good amount of work done!

-Finally removed the lug from the cylinder.
-Working on cleaning up the power valve
-All parts from the 04 yz250f are off. I will need to get a 04 yz250 or yz450f bottom clamp as the 250f is two short
-working on mocking up the 95 with the 04 swingarm, linkage, shock and rear wheel. From my understanding the main difference is the inner bore of the steel bushing are bigger and a bit longer on the 04 to use a bigger swingarm axle. My plan is to use the bushing from the 95 trimmed to the size of the 04. The swingarm will bolt right up after!
-Some advantages of this is that you can use new wheel set, new brake parts, linkage ratio is much better, and parts are much easier to find!

I'll update with some pictures later tongiht
Zach_K
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Sneads Ferry, NC, USA
1/29/2018 9:14pm Edited Date/Time 2/2/2018 8:33am
Got the 2004 yz250f rear end mounted. I will need to trim down the 95 yz250 swingarm bushings to match the size of the yz250f bushings


As you can see they stick out ever so slightly on the inside. This is due to the 95 using thrust bearings on the outside of the swingarm


Added the rear brake. Need some rear spacers.


Rear master mounts perfectly which removes the need for a reservoir.


You can see here the 04 250f stem is short


Zach_K
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Sneads Ferry, NC, USA
2/1/2018 9:05pm Edited Date/Time 2/2/2018 8:36am
Sorry guys need to edit my post! But here’s more photos

Take a guess!


The top fork tube coating has seen better days. May run them for a while until I can get the coated or replace with SSS forks


Also found small nicks near the lug. I'll have to do research on if I can fix this myself or not?


The perfect fork fluid...


Zach_K
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Sneads Ferry, NC, USA
2/2/2018 8:37am
What do you guys think I should do with the forks? if I were to coat them I would make them look like emigs bike, but is it really work the cost?
FWYT
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San Diego, CA, USA
2/2/2018 1:29pm
Zach_K wrote:
What do you guys think I should do with the forks? if I were to coat them I would make them look like emigs bike, but...
What do you guys think I should do with the forks? if I were to coat them I would make them look like emigs bike, but is it really work the cost?
I think the money spent on coating older forks could be better spent elsewhere.
Zach_K
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Sneads Ferry, NC, USA
2/2/2018 5:40pm
FWYT wrote:
I think the money spent on coating older forks could be better spent elsewhere.
That’s what I’m thinkin
FWYT
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San Diego, CA, USA
2/2/2018 11:57pm
So that rear brake reservoir was a perfect fit? That's sweet! I'm going to do that, too, so
as to be able to get rid of the reservoir, tube and bracket. Thanks for the tip!!
Zach_K
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Sneads Ferry, NC, USA
2/3/2018 8:49am
FWYT wrote:
So that rear brake reservoir was a perfect fit? That's sweet! I'm going to do that, too, so as to be able to get rid of...
So that rear brake reservoir was a perfect fit? That's sweet! I'm going to do that, too, so
as to be able to get rid of the reservoir, tube and bracket. Thanks for the tip!!
Yeah man! I’m using the 04 swing arm and linkage as well
Zach_K
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Sneads Ferry, NC, USA
2/3/2018 2:01pm
So today I decided to try and get the 04 pegs to work for it to fit perfectly but need to find a spring that will fit. Any ideas?




Zach_K
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164
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6/13/2017
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Sneads Ferry, NC, USA
2/8/2018 7:14am
Little Update:

-Going to get the engine shipped off tomorrow!
-Subframe ordered!
-Front forks have 4.0 kg springs...I'm 185 so they may be a little soft for me.
-Currently working on removing bearings. The linkage bearings are giving me hell. I've take a torch to them then tried to press them out with a vise. I've gotten about a 1/4 inch of movement. Time to pull out the dremel!
-Still trying to decide what I want to do with the wheels...stick with the stockers or order some tusk wheels. May just use the stock wheel for now. I'm hoping to have a roller by the time the engine is done.
-My current plan is to go on a road trip to VA and have the motor installed by the mechanic who is part of the VetMx community. Then ride the beauty on a track out in VA with other VetMx members!


lcgordon711
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Denver, CO, USA
2/8/2018 7:35am
A little heat and a vice those should come right out.
Zach_K
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Sneads Ferry, NC, USA
2/8/2018 7:49am
A little heat and a vice those should come right out.
I did that and no dice. Used a heat gun and vise and then tried using a torch. It was bending the vise turn bar.
lcgordon711
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Denver, CO, USA
2/8/2018 9:03am
Which part of the linkage are you trying to get the bearing out of. Is it the dog bone piece/U shaped piece or the other part the shock bolts up to which is one chunk of metal with 3 holes?

On my 08 Yamaha the dog bone piece had a shoulder and you have to pull them out the way they went in and cant push them through. Not sure on your bike see if you can post a pic or something.
Zach_K
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Sneads Ferry, NC, USA
2/8/2018 11:02am
The 3 hole part. I didn't see a shoulder but I will have to check tonight.
lcgordon711
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Denver, CO, USA
2/8/2018 11:09am
That part did not have a shoulder. Never know my bike and yours are over 10 yrs apart but I would try to check if you can
Zach_K
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Sneads Ferry, NC, USA
2/8/2018 9:19pm
No good! My vise snapped


But resorted to uses a standard hammer and waaa laaa


I think I can save these Woohoo


lcgordon711
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632
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Denver, CO, USA
2/9/2018 5:55am
Good news on the bearings bad news on the vice. I will say I used a pretty big vice for mine so that maybe helped
Shift13
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11/20/2020
Location
Blacksburg, VA, USA
11/20/2020 10:56am
Zach_K wrote:
I’ll be posting photos on my phone then updating later on.. Breaking it down: luckily no seized bolts so far. Lots of PB blaster and wb...
I’ll be posting photos on my phone then updating later on..

Breaking it down: luckily no seized bolts so far. Lots of PB blaster and wb.


Next is to work on the rear end


Popped open the engine to get a look at what I could be dealing with. From the cylinder you can see some type of fluid; I'm guessing coolant? What you guys thinks? Hows she look?


Working on the rear end...The brake fluid is (well what is left) is a black sludge


SO I'm stuck. Last night I loaded the front swing arm bolt with lots and lots of lube as I couldn't get the bitch to budge. Every "big bolt" on the bike two sides to work with except this bolt. Any tips on getting it? Hopefully all the lube penetrates it and its easier the next time I work on the bike.

I signed up because i thought that was my old bike from 1997 but i dont think it is. Mine had a few things that might have been fixed over the years but you dont see many long rod 95 yz builds with blue frames. When i owned one i was in northern va.


An even more rare build would be to find an ohlins 360 kit when the bikes were raced in open classSmile


Im sure you know but the 95 yz had 46mm forks and that 04 250f ws the first year for the 48mm forks. Hope to see some updates on this. I loved my 95 back in the day and long to build one again. When i sold mine to my boss at the time he used some of the gytr factory blue and white kits he bought(we worked at a yamaha dealer) to sell the bike when i went to college. He had a 95 with the 360 with the factory blue and white wvwn with the blue tank. My bike would have had a white tank on itas the navy blue was no longer for sale since 96 yamaha officially went blue.
Still riding
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3/4/2020
Location
Bountiful, UT, USA
2/11/2021 11:51am
It's been a few months, any updates with this long rod build?

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