bottom end rebuild DIY

[Lquad71]

So im going to try out rebuilding my bottom end. I have a blown motor that threw a rod so im going to do it a couple times on that before i do it on my motor. But if anyone has any tips on how i should go about doing this then that would be great. Also if anyone knows if i dont need any of the special tools or if i can improve that would save me a lot of money. Thanks.

[eastside 400]

only special tools you need are a flywheel puller, balancer shaft socket, and a clutch holder. if you dont have a manual then make sure you get one. If you need to replace bearings, put the new one in the freezer for a few hours and warm the case with a heatgun and they go right in. make sure you use loc-tite on bolts that need it. dont hammer on the crank. make sure your balancer marks and everything line up

[Lquad71]

Thanks for the reply. Just a couple questions. What do i use the balancer shaft socket for? Will the flywheel puller work for a crf450 flywheel? And what would you recommend for removing bearings the best way possible? Thanks again.

[eastside 400]

1. the balance shaft socket is for the balancer shaft...the nut on the end needs a pronged socket... it looks like you have a 05 so this is the tool http://www.motionpro.com/motorcycle/partno/08-0015/

2. Not sure if the crf one will work

3. Just use a socket and a hammer and knock the old bearings out, they usually arent hard to get out.

[jt04-450r]

just did my first rebuild, I followed the manual and every thing went great. I bought the tools listed above (not to expensive). Just follow the manual and the directions of the very good people on here and it will go easier than you think.

[MX450]

That motion pro tool listed above will not work, it is not deep enough, i made that mistake with my 05. you need one like this..

http://www.ebay.com/itm/Honda-Oil-Filter-Clutch-Hub-Spanner-Tool-125-110cc-ATV-/160610640427?pt=Motorcycles_Parts_Accessories&vxp=mtr&hash=item256523e22b

and DEFF get a honda service manual

[MX450]

also putting the bearings in a cooler with dry ice makes them super cold and doesnt take as long as the freezer

[eastside 400]

the motion pro tool will work, you just need to make it a little deeper, i used a large drill bit, you could use a die grinder also... but that one you found is the way to go, ive used one of them before but couldnt find it to put a link on here so i just showed the one i have. that other one is nice because it has both sizes

[Lquad71]

thanks guys.your were all a big help. and yea i already have a service manual. i wouldnt even attempt it without it.

[Lquad71]

so i have everything apart, the only problem is getting the crankshaft bearings off of the crankshaft. I got the crank out and i do not need it, but i would like to know how to get the bearing off without a special tools if its possible. and can i just hammer out the right crank bearing and be fine?

[MX450]

are you planning on reusing the bearing? I would just get new ones. Here is how to get it off.. looks like you will need a tool.

http://www.youtube.com/watch?v=q38HUzr043c

For getting the right bearing out i would suggest heating the cases up with a heat gun or something and it will come out much eaiser, it will just about drop out, that way you are not hammering on your cases.

[Lquad71]

Thank you. and no im replacing everything, just kinda curious if i could do it without any special tools.

[mikey726]

If you're going to use a tool like that to pull the bearing off the left side of the crank, I would suggest putting the threaded cap from your flywheel puller over the end of the crank instead of centering the point of the tool in the end of the crank. There's a small oil passage in there and I wouldn't want to risk damaging it.