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Contemplating complete restoration of yz125

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Hello,

Situation: A yz125 has fallen into my lap. I don't know anything about its history, and guess it to be 2000-2001ish. It has been sitting outside for a few years, and hasn't been ridden in at least that long. It looks to be in pretty rough shape (rust on the frame, missing a kickstarter, brakes appear disconnected, busted exhaust etc.). I grew up riding dirt bikes (4 strokes) but have limited mechanical background (no background with 2 strokes). I am considering attempting to restore this bike to rideable condition as a pet project.

Questions: Am I in over my head? Is this an impossible task for someone who has never worked on a 2 stroke? Any suggestions/tips on where to start? Any guesstimates on total cost and/or hours required (I realize this question is impossible to accurately answer - just looking for a rough estimate)?

Any input is greatly appreciated.

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Hello,
Situation: A yz125 has fallen into my lap. I don't know anything about its history, and guess it to be 2000-2001ish. It has been sitting outside for a few years, and hasn't been ridden in at least that long. It looks to be in pretty rough shape (rust on the frame, missing a kickstarter, brakes appear disconnected, busted exhaust etc.). I grew up riding dirt bikes (4 strokes) but have limited mechanical background (no background with 2 strokes). I am considering attempting to restore this bike to rideable condition as a pet project.
Questions: Am I in over my head? Is this an impossible task for someone who has never worked on a 2 stroke? Any suggestions/tips on where to start? Any guesstimates on total cost and/or hours required (I realize this question is impossible to accurately answer - just looking for a rough estimate)?
Any input is greatly appreciated.

Its not impossible. 3500+ and 100 hours. Buy a manual.
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49 minutes ago, WcodyR said:

Hello,

Situation: A yz125 has fallen into my lap. I don't know anything about its history, and guess it to be 2000-2001ish. It has been sitting outside for a few years, and hasn't been ridden in at least that long. It looks to be in pretty rough shape (rust on the frame, missing a kickstarter, brakes appear disconnected, busted exhaust etc.). I grew up riding dirt bikes (4 strokes) but have limited mechanical background (no background with 2 strokes). I am considering attempting to restore this bike to rideable condition as a pet project.

Questions: Am I in over my head? Is this an impossible task for someone who has never worked on a 2 stroke? Any suggestions/tips on where to start? Any guesstimates on total cost and/or hours required (I realize this question is impossible to accurately answer - just looking for a rough estimate)?

Any input is greatly appreciated.

Find thread "restorations by P841" to see what you have and could have. Many hours, many $$, but the fun outweighs it all. 

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51 minutes ago, WcodyR said:

Hello,

Situation: A yz125 has fallen into my lap. I don't know anything about its history, and guess it to be 2000-2001ish. It has been sitting outside for a few years, and hasn't been ridden in at least that long. It looks to be in pretty rough shape (rust on the frame, missing a kickstarter, brakes appear disconnected, busted exhaust etc.). I grew up riding dirt bikes (4 strokes) but have limited mechanical background (no background with 2 strokes). I am considering attempting to restore this bike to rideable condition as a pet project.

Questions: Am I in over my head? Is this an impossible task for someone who has never worked on a 2 stroke? Any suggestions/tips on where to start? Any guesstimates on total cost and/or hours required (I realize this question is impossible to accurately answer - just looking for a rough estimate)?

Any input is greatly appreciated.

Find thread "YZ restorations by P841" to see what you have and could have. Many hours, many $$, but the fun outweighs it all. 

Here

 

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Hello,
Situation: A yz125 has fallen into my lap. I don't know anything about its history, and guess it to be 2000-2001ish. It has been sitting outside for a few years, and hasn't been ridden in at least that long. It looks to be in pretty rough shape (rust on the frame, missing a kickstarter, brakes appear disconnected, busted exhaust etc.). I grew up riding dirt bikes (4 strokes) but have limited mechanical background (no background with 2 strokes). I am considering attempting to restore this bike to rideable condition as a pet project.
Questions: Am I in over my head? Is this an impossible task for someone who has never worked on a 2 stroke? Any suggestions/tips on where to start? Any guesstimates on total cost and/or hours required (I realize this question is impossible to accurately answer - just looking for a rough estimate)?
Any input is greatly appreciated.

Pictures please!!!

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Good news!

1 - Your initial "purchase" price was good

2 - Parts are plentiful

3 - Used, trick aftermarket parts can be had cheap on ebay

4 - YZs hold together well and hold their value well (variables apply)

5 - The project will be fun & gratifying

6 - 2-strokes are easy to work on.

 

Not-so-Good News

1 - It will still cost $$, and you will probably never recoup your investment

2 - Your wife/girlfriend/significant other may think you are crazy/selfish/unloving/etc.

3 - It will be a time bandit

4 - It may turn into a passion/habit/addiction

 

Good luck, and keep us updated with what you do. :thumbsup:

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Good news!
1 - Your initial "purchase" price was good
2 - Parts are plentiful
3 - Used, trick aftermarket parts can be had cheap on ebay
4 - YZs hold together well and hold their value well (variables apply)
5 - The project will be fun & gratifying
6 - 2-strokes are easy to work on.
 
Not-so-Good News
1 - It will still cost $$, and you will probably never recoup your investment
2 - Your wife/girlfriend/significant other may think you are crazy/selfish/unloving/etc.
3 - It will be a time bandit
4 - It may turn into a passion/habit/addiction
 
Good luck, and keep us updated with what you do.

NSGN #2 should be #1, in my experience.
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3 hours ago, P84ONE said:

Find thread "YZ restorations by P841" to see what you have and could have. Many hours, many $$, but the fun outweighs it all. 

Here

 

Awesome thread... thanks for sharing... I will be referencing this often...

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Thanks very much for all of your responses... I will be getting my ducks in a row on this project hopefully this weekend, and will post pics

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I restore these things for way 

cheaper, probably less than

$1000 ...unless the cyl needs

replating, add $300 to &400

1) get the microfiche

2) determine if you want a

 show bike, or something

to thrash

3) look on Ebay Stores, as there

are shops that can supply

everything you need ( top end or

full engine rebuild kits,

gasket kits,  suspension and 

wheel bearing kits,

bodywork and plastic, etc )

with one shipping cost.

 

Edited by yamaha7654
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Here are some pics of bike in question... 1st issue is that engine will not turn over... Any suggestions on how to approach this issue? Thinking it probably needs a top end replacement in any case, so will probably begin removing the motor tonight...

20170622_195403.jpg

20170622_195421.jpg

20170622_195354.jpg

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Nice thing is, it looks pretty complete. I would say the top/bottom needs full recovery love, carb rebuilt and set properly, all linkage and bearings looked at, and whell bearing...just replace them, they are cheap. 

Get a list of parts going for body work, shoot all the shroud screws on tank with PB penetrating oil. 

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20 hours ago, P84ONE said:

Nice thing is, it looks pretty complete. I would say the top/bottom needs full recovery love, carb rebuilt and set properly, all linkage and bearings looked at, and whell bearing...just replace them, they are cheap. 

Get a list of parts going for body work, shoot all the shroud screws on tank with PB penetrating oil. 

Will do. Popped the cylinder head off and noticed some metal in the cylinder... without having removed the cylinder yet everything looks on tact so I'm wondering where the metal came from?

 

To be continued...

20170624_134104.jpg

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On 6/6/2017 at 9:14 AM, CaptDan said:

Good news!

1 - Your initial "purchase" price was good

2 - Parts are plentiful

3 - Used, trick aftermarket parts can be had cheap on ebay

4 - YZs hold together well and hold their value well (variables apply)

5 - The project will be fun & gratifying

6 - 2-strokes are easy to work on.

 

Not-so-Good News

1 - It will still cost $$, and you will probably never recoup your investment

2 - Your wife/girlfriend/significant other may think you are crazy/selfish/unloving/etc.

3 - It will be a time bandit

4 - It may turn into a passion/habit/addiction

 

Good luck, and keep us updated with what you do. :thumbsup:

With a 125, I guarantee you will come nowhere near the cost of repair. I have about $2,700 into my 2002 CR125 now. I'd be DAMN lucky to sell it for $1,500. :bonk:

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1 hour ago, WcodyR said:

Will do. Popped the cylinder head off and noticed some metal in the cylinder... without having removed the cylinder yet everything looks on tact so I'm wondering where the metal came from?

 

To be continued...

20170624_134104.jpg

Mystery solved... Any thoughts on what the implications of piston fragment(s) stuck in the crank are? IF I can remove it without opening the bottom end would it be safe to just replace the piston or am I definitely going to need the bottom end redone?

20170624_151325.jpg

20170624_151717.jpg

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You are going to need to pull the crank and replace the main bearings and seals at a minimum. The rod bearing on the crank may be "ok", but you will need to measure play to be sure. No telling how much skirt is in the bottom end, and flushing it could be an option, but best play it safe and crack it open. 

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4 hours ago, markmc2 said:

fyi, you can drain the coolant at the pump on right side of engine.

I removed the drain bolt before I began, but obviously it didn't all drain... made quite a mess... thinking it's because I didn't loosen the radiator cap when I took the drain bolt out

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