Installing a Crank

Are there any Safe and Reliable ways to install a crank without dropping the cash on a crank installer?  I would like to save the $60 as this would be a special limited use tool..

Put the crank in the freezer for the day. when ready to drop in, heat the outer race of the bearings with a propane torch. it will all drop in place like butter

What he said,

ive done over 20 motors like this, freeze the crank and heat the bearings, when done correctly everything just falls in without any effort.

BreakneckYZ,  RMATVMX have a good video on youtube showing a YZ250 crank swap.

 

What he said,

ive done over 20 motors like this, freeze the crank and heat the bearings, when done correctly everything just falls in without any effort.

Adam, I'm going to have to replace my crank assembly soon-ish. Big end sounds a bit loud.  Where I live, getting into the job and then finding I need some worn seal or small part I don't have is a major time waster.  Since you've done 20+ please tell me what extra little YZ250 motor parts should I order in advance "just in case"?    My motor seems good, gear shift shaft, clutch action, etc, but I know some little parts will be shagged out.  Thanks in advance.

BreakneckYZ,  RMATVMX have a good video on youtube showing a YZ250 crank swap.

 

Adam, I'm going to have to replace my crank assembly soon-ish. Big end sounds a bit loud.  Where I live, getting into the job and then finding I need some worn seal or small part I don't have is a major time waster.  Since you've done 20+ please tell me what extra little YZ250 motor parts should I order in advance "just in case"?    My motor seems good, gear shift shaft, clutch action, etc, but I know some little parts will be shagged out.  Thanks in advance

 

Dont really know till you dive in. I know what you mean though its a pain to wait for one single part.  pretty much a standard topend gasket kit will do and a tube of yamabond, new piston, piston pin bearing, c clips. for the topend.

 

 Its loud? Replace the crank bearing and seals while in there.  For the crank itself, Honestly just have it rebuilt by kenoconnorracing.com they do amazing work and a crank rebuilt by them is better than a new oem one out of the box (cheaper t0o). watch the video, they even fix a major flaw in the yz250 crank design. pull the transmission shafts and gears out, its less scary than it sounds. and put some force on each bearing race with your finger and spin the bearing, if you feel any and I mean any roughness in a bearing, pull and replace it. I just use my local bearing supply store, bring in the old ones and they find matching new ones. Japanese made, dont care the brand long as they are quality

 

 

 

 

what year is it? do you have a manual?  Ever have a question just ask or drop me a line in my inbox. All the motors I do, i only need a flywheel puller. I make my own case splitters our of scrap metal i have laying around. Heat and cold are how i rebuild all bottom ends so zero force is needed.

Dont really know till you dive in. I know what you mean though its a pain to wait for one single part.  pretty much a standard topend gasket kit will do and a tube of yamabond, new piston, piston pin bearing, c clips. for the topend.

 

 Its loud? Replace the crank bearing and seals while in there.  For the crank itself, Honestly just have it rebuilt by kenoconnorracing.com they do amazing work and a crank rebuilt by them is better than a new oem one out of the box (cheaper t0o). watch the video, they even fix a major flaw in the yz250 crank design. pull the transmission shafts and gears out, its less scary than it sounds. and put some force on each bearing race with your finger and spin the bearing, if you feel any and I mean any roughness in a bearing, pull and replace it. I just use my local bearing supply store, bring in the old ones and they find matching new ones. Japanese made, dont care the brand long as they are quality

 

 

 

 

what year is it? do you have a manual?  Ever have a question just ask or drop me a line in my inbox. All the motors I do, i only need a flywheel puller. I make my own case splitters our of scrap metal i have laying around. Heat and cold are how i rebuild all bottom ends so zero force is needed.

Thanks! Parts should be here today for me to put the bottom end together. I appreciate the advice!

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