You dont need a press to seat the crank into the cases. if you heat up the inner main bearings with a small torch or wind proof lighter the crank will slide in by hand. and it doesnt take much heat to do it.
Do you center the crank? I had a yz250 crank that would get stiff to spin after trying case bolts. Turned out the crank was just a little too far right of center. It may have corrected itself during break in though.
I don’t worry too much about it on these bikes. There are some that you have to center but the yamaha’s will break in and be perfect as long as you are easy on break in.
I have a 2002 yz125 that I want to bore out to a 144. In the description of this video you reference a YZ144 Build playlist. I looked and didn't actually find this playlist. Please tell me I just don't know how to work TH-cam . Where is it? I rode this bike for years and years and it's so clapped out. I'm too emotionally invested in it and want to go through the whole thing with freshies as a fun/aggravating/educational winter project.
Hey is this the same bottom end as a 1994-95 yz im about to do my first full rebuild and I dont wanna waste my money also if you think I can do something to improve the design let me know please I love my yz
Just wondering what the cost of a complete rebuild of the motor like that would be. I have a blown yz 144, haven’t dug in to find exactly what happened but I’m just curious how much it might cost if all the internals needed replaced? Thanks in advance!
I have a 01 yz125 and keeps missing 2nd had it apart 2 times first it was not hitting neutral tore it down got new clutch’s got neutral back now missing 2nd straight to neutral any idea what could be wrong any ideas @ me
@@highlandcycles I did a rebuild on my 98 YZ 125. And got it all back together went riding. Everything is fine but I found the O-ring that goes between the cases. I failed to install. Where the water flows flows through the crank case. I did use Honda Bond. so I guess what I’m wondering is should I tear it back down and install that O-ring or just run it the way it is and hopefully it doesn’t leak antifreeze into the crank case. What are your thoughts? Thank you for any info.
Why wouldn’t you have a nice flat surface to rest the case halves on while you drive the bearings in ? That diamond plate bike stand work bench gave me anxiety
Lots of motor builders and mechanics use a 2x4 box like that. It provides cushion and allows you to get the cases oriented. Flat surfaces make it impossible to get the motor flat
Its so interesting to watch engines go together.... Weird, right? 👀 The GPX is finally back in action 💪 seems the reg ec got smoked with all shorting form the loose connection. Its been down for over 6 weeks now with all this crap, but tomorrow... I Ride!!
![ลองสุ่มไอโฟน 990 โกงมั้ย? [ โกงมั้ยครับ ep.101 ] | DOM](http://i.ytimg.com/vi/bfsWe0j492k/mqdefault.jpg)
You dont need a press to seat the crank into the cases. if you heat up the inner main bearings with a small torch or wind proof lighter the crank will slide in by hand. and it doesnt take much heat to do it.
Right on
You have to tap the crank with a mallet after installing. It will square it in the crank bearings / bore and rotate smoothly.
Good tip
I prefer to use a crank puller, and a case splitter/puller for installing cranks and pulling cases apart or putting them back together.
That works great too.
Brilliant video. I was trying to put the transmission back into my 426 and gave up until another day, such a pain in the A.
Hahaha. It can be.
We are rebuilding a 02 yz 125 this has been so helpful thanks ! Do we need to mess with the case to bore it out?
Depends on the kit but the Athena one doesn’t require messing with the case
Thank you
Nice work mate!!!!
Thanks
I pressed my cases together and the crank is a bit tight to move I made sure main bearings were pressed in pretty straight
If it’s not too tight it will loosen up when it warms up
Mf the supa villain
Do you center the crank? I had a yz250 crank that would get stiff to spin after trying case bolts. Turned out the crank was just a little too far right of center. It may have corrected itself during break in though.
I don’t worry too much about it on these bikes. There are some that you have to center but the yamaha’s will break in and be perfect as long as you are easy on break in.
I have a 2002 yz125 that I want to bore out to a 144. In the description of this video you reference a YZ144 Build playlist. I looked and didn't actually find this playlist. Please tell me I just don't know how to work TH-cam . Where is it? I rode this bike for years and years and it's so clapped out. I'm too emotionally invested in it and want to go through the whole thing with freshies as a fun/aggravating/educational winter project.
I might have deleted that list but the vids are still up. But the main thing is that I bought the Athena 144 kit. It comes with everything you need.
Got a question for u I got an 2000 YZ 125 is there a ball bearing for the Push rod ????
Not sure. Have to look at a parts fiche
Is it necessary to replace the transmission bearings if need to you replace the crank bearings?
Not necessarily. It really depends on their condition and how many hours they have on them.
Hey is this the same bottom end as a 1994-95 yz im about to do my first full rebuild and I dont wanna waste my money also if you think I can do something to improve the design let me know please I love my yz
It’s close
@@highlandcycles cool thank you
Just wondering what the cost of a complete rebuild of the motor like that would be. I have a blown yz 144, haven’t dug in to find exactly what happened but I’m just curious how much it might cost if all the internals needed replaced? Thanks in advance!
And please add in labor cost as well!
@@lost4058 usually it ends up being around $1500
Is that something your willing to do? I have a 04 yz125 and the engine needs to be rebuilt
I have a 01 yz125 and keeps missing 2nd had it apart 2 times first it was not hitting neutral tore it down got new clutch’s got neutral back now missing 2nd straight to neutral any idea what could be wrong any ideas @ me
Not sure. Is a shift fork bent?
Were you hitting the bearings in on the inner race of the bearing? Is that bad to do?
No, I was hitting the outer race. Hitting the inner race is bad
Wondering if you answer questions?
Yep
@@highlandcycles I did a rebuild on my 98 YZ 125. And got it all back together went riding. Everything is fine but I found the O-ring that goes between the cases. I failed to install. Where the water flows flows through the crank case. I did use Honda Bond. so I guess what I’m wondering is should I tear it back down and install that O-ring or just run it the way it is and hopefully it doesn’t leak antifreeze into the crank case. What are your thoughts? Thank you for any info.
I bought a bike with this 144cc kit, and i have a question, the connecting rod used, is the original of 125? My bike is 2004, thank you
Yes it is.
@@highlandcycles thanks for your answer. greetings from Argentina!
@@laautiquiroz3086 Salud!
Why wouldn’t you have a nice flat surface to rest the case halves on while you drive the bearings in ? That diamond plate bike stand work bench gave me anxiety
Lots of motor builders and mechanics use a 2x4 box like that. It provides cushion and allows you to get the cases oriented. Flat surfaces make it impossible to get the motor flat
What would all those parts run ball park estimate?
Full motor kit from wrench rabbit is about $600
Its so interesting to watch engines go together.... Weird, right? 👀
The GPX is finally back in action 💪 seems the reg
ec got smoked with all shorting form the loose connection. Its been down for over 6 weeks now with all this crap, but tomorrow... I Ride!!
Awesome man
@@highlandcycles q
😊
What are the dimensions for the 2×4 box
I don’t know and I’m not at the shop but it’s about 8”x14”
How much would a job like this cost ?
$900 if you bring the whole bike in
link yo shui
What year bike is this you’re working on ?
This is a 2002
👍👍👍
Braap
👍🇬🇧
@@richardhartley7094 Yeah