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Restoring a 1995 KX125

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Hey guys,

I bought a 1995 kx125 back in 2001.  Didnt know anything about car or bike maintenance other than changing oil.  I was young and dumb lol.  I was riding my kx one afternoon, and took way too big of a jump.  When I landed, my foot came off my peg and broke my tibia and fibula in half.  I could have bled to death if it was not for my riding boots.  My artery was pushed up against a sharp point of my broken bone.  

That was enough to scare me off my bike.  I have had it sitting out in a shed since (16 years).  I have the urge to get back on it and ride now, just more for trail riding rather than racing and tricks.  

Now, I have a lot more mechanical experience.  Started digging into the bike to get it started.  I really enjoyed the fact that I could get pretty far into the engine with just an 8 mm socket.  I have been browsing this forum for a couple of weeks now, as I had coolant in the oil.  I rebuilt the water pump, and didnt see much damage/rust inside the case.

Once I cleaned out the carb and gas tank and rebuilt the water pump, it started right up.  Had to slightly adjust the carb and now it idles great.  Now that it is running, I need to start looking at the details.  I don't want to get stranded in the desert.  Sorry for all the questions, but any feedback would be appreciated.  

1.  I uploaded a 15 second clip of my bike running on google drive.  Would you guys mind watching it and let me know if my bike sounds normal?  When I get up close to the case, you can hear some "chatter".  Is this normal for a 2 stroke or does it sound bad?  

2.  I was reading about top end rebuilds, and how if you delay the maintenance you will cause a lot of damage and get stranded.  It has never had the top end done to my knowledge.  But I would like to at least take it out a few times to see if I am going to be ok riding a bike again before I start really dumping money into it.  I know nobody can tell for sure, but would you guys think a couple of rides could be done before I rebuild?  I really have no idea how many hours are on it right now.  I maybe rode it 10 hours before my accident but I dont know about the previous owners.  

3.  I am assuming the brakes should all be bled, sitting for that long?  

4.  The chain has some surface rust, but does not look really bad.  How would I know if I need a new chain?  Should I just tighten it up and see how it goes?  

5.  The tires have a lot of rubber left, but they are many years old.  They are holding air and not dry rotted, do you think they are safe to use or should I replace those too?

6.  The only part of the bike that was damaged in my accident was the muffler expansion pipe.  There is a hairline crack about 2 inches  long where a little bit of exhaust escapes.  Is this ok to leave?  It does not bother me but I read that it could cause a lean condition and be hard on the motor.  

7.  When I took the expansion pipe off to rebuild the water pump, there was some copper gaskets that fell off between the muffler and engine.  They were more of a C look than a complete circle, and I could not see how they fit back in there.  They did not seem to fill any purpose so I left them out.  Is this going to cause any problems?  

8.  Is there anything else that I should check before taking the bike out for a ride?  

Thank you all, I know I have a lot of questions but I will keep searching the forms in the meantime.  Any knowledge you can share would be appreciated.  

Here is the video:

Click here for Video

Edited by azcrash

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Here are a few pictures of the bike.  As you can see in the first pic, there was a small amount of rust in the crank but that was it.  I filled the transmission with type F fluid, going to run it for about 15 minutes and then drain and fill again.  

IMG_6903.JPG

IMG_6898.JPG

IMG_6901.JPG

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Bleed the brakes, replace the coolant - fix that split in the pipe, it will only get worse

Oil the chain, check the air filter - replace if its crumbly, or re-oil it

Make sure all your cables are moving freely - squirt some wd40 down them

Bolt it all back together - take it for a good run - then check the engine noise again

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The copper between your cyl and pipe is so the pipe doesn't wobble around and beat up the exhaust port, easy to get a new one, I would.

Sent from my Moto G Play using ThumperTalk mobile app

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Thanks for the feedback so far.  I will get a copper ring for the exhaust and I am in the process of getting the muffler welded now.  

Will also get the brake fluid flushed this weekend.  

So the chain and tires should be ok?  Was anyone able to view the video to see if that noise was normal?  I would hate to go blow my engine on something that I could have prevented.  

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Your tires may not look bad now, but after they sustain a bit of pressure from normal riding and a few little jumps, they will rip apart.

 

Good luck on the build.

 

Sorry, but I did not read the doctoral thesis in your 1st post.

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Was there a air filter in it ? I was zooming on the pics I didn't see one but maybe you took it out ? What does the piston look like through the exhaust since you have it off ? You can probably assume it could use a fresh top end . I also recommend re packing the silencer .

Sent from my Moto G (4) using ThumperTalk mobile app

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