removal of crank bearings

[Mikel.Laundry]

i am rebuilding my rm 125 and i cant get the bearings of the crank . i know you can use a special tool that goes behind it and pushes on the shaft but is there like a redneck way of getting them off?

[tribalbc]

Good old torch and a rubber mallet.

[Mark6299]

i am rebuilding my rm 125 and i cant get the bearings of the crank . i know you can use a special tool that goes behind it and pushes on the shaft but is there like a redneck way of getting them off?

the tool is rather cheap. But it and then you will have it for later and you could rent it to your buddies who ride too. The bearing puller is not model specific so it would work on most if not all cranks. If you beat on it you will surly be out of more money than if you bought the correct tool. I would even bet that an auto dealer has one that will work for free rental.

[tribalbc]

the tool is rather cheap. But it and then you will have it for later and you could rent it to your buddies who ride too. The bearing puller is not model specific so it would work on most if not all cranks. If you beat on it you will surly be out of more money than if you bought the correct tool. I would even bet that an auto dealer has one that will work for free rental.

A rubber mallet is not going to put a crank out of balance. It should pretty much fall out with the torch, the mallet is just to give it a nudge.

[KTM-548cc]

how is any type of hammer going to get a bearing off when its tight against the crank wheel. maybe pound a big chisel in there hahahahhaa

thats what a clam shell puller is for like the other dude suggested. guess you never heard of one. why use the right tool when theres a big ass hammer handy ?

[argclh6670]

heybro, just google youtubes video featuring how to split cases on 2 strokes by Rocky Mountain ATV its very informative. When i rebuilt my sons 125, i bought a automotive pully/bearing puller got longer bolts and wahla! now, to get the bearings out of the cases, i did what the video said put cases on clean flat wooden surface, and used a hammer and socket that filled up majority of exposed bearing, and pop! fell right out. dont havta pound them out just a good smack. some may say not use that method, but if RMATV does it so will i.

[Mark6299]

A rubber mallet is not going to put a crank out of balance. It should pretty much fall out with the torch, the mallet is just to give it a nudge.

Did you just make that up or did you try it yourself? If you ad heat to the bearing it will grow but at the same time you will add heat to the crank which will also grow. I have NOT tried it but it's common scense.

[tribalbc]

Did you just make that up or did you try it yourself? If you ad heat to the bearing it will grow but at the same time you will add heat to the crank which will also grow. I have NOT tried it but it's common scense.

Yup, just made it up, never tried it?

The bearing will expand faster than the crank. Works even better if you freeze the whole assembly first for a few days.

Ok, here's a better explanation.

Mount bearing in a vice with crank on lower side.

Now take a torch to the bearing and get it good and hot.

Give the crank end some hits down with the rubber mallet to remove.

If this doesn't work you will have to resort to a gear puller, etc but it is certainly worth a try for the effort involved.

[Mikel.Laundry]

i have tryed the torch but i think i heated the crank at the same time. i will give it a try again the whole thing was the same temp last night

[tribalbc]

i have tryed the torch but i think i heated the crank at the same time. i will give it a try again the whole thing was the same temp last night

Try throwing it in the freezer overnight + first.

[KTM-548cc]

if you insist using a torch then have somebody tap some screwdrivers or small wedges of wood or something behind the bearing while you heat it. if that dont work then maybe you can get a jaw puller behind it. if that dont work then do what i said a few post earlier and use bearing splitter. 100% that will work. like the other dude said maybe put it in the freezer if you continue with the torch idea

[Padgett]

Yup, just made it up, never tried it?

The bearing will expand faster than the crank. Works even better if you freeze the whole assembly first for a few days.

Ok, here's a better explanation.

Mount bearing in a vice with crank on lower side.

Now take a torch to the bearing and get it good and hot.

Give the crank end some hits down with the rubber mallet to remove.

If this doesn't work you will have to resort to a gear puller, etc but it is certainly worth a try for the effort involved.

Yes it works and yes I have done it many of times. The OP asked for a redneck way and this is the number one way even if you use the bearing tool with the heat. To pull the bearing dry with the puller leaves galled markes on the crank shaft. The heat helps release the bearing from the shaft.

[tribalbc]

Yes it works and yes I have done it many of times. The OP asked for a redneck way and this is the number one way even if you use the bearing tool with the heat. To pull the bearing dry with the puller leaves galled markes on the crank shaft. The heat helps release the bearing from the shaft.

I guess we're the only rednecks around here?

[swolf]

For assembly I freeze the crank and heat up the bearings in the oven. goes together easy. I don't like hitting a new bearing with a hammer.?

[Mark6299]

For assembly I freeze the crank and heat up the bearings in the oven. goes together easy. I don't like hitting a new bearing with a hammer.?

This is one of the best ways in my opinion to do this part of the project especially on a crank. You might even try using dry ice, unless hillbillies don’t have that either. I don't like the idea of pressing the main bearings on with an offset unsupported situation that you get with the rod big end bearing.

And by the way, all that over two days in the freezer stuff is nonsense. If it’s at x degrees cold then it’s x degrees cold, no matter how many days or hours it’s in the freezer.

As far as the heat and beat method goes, if he stopped dicking and go with the right tool for the job, he would have been done by now. I am almost certain that his local shop has that tool for cheap. As far as the OP asking for a redneck solution comment goes, I guess I could have told him to use a dremmel tool or die grinder and get it off that way, but many times there is no substitute for the right tool for the job.

[tribalbc]

This is one of the best ways in my opinion to do this part of the project especially on a crank. You might even try using dry ice, unless hillbillies don’t have that either. I don't like the idea of pressing the main bearings on with an offset unsupported situation that you get with the rod big end bearing.

You're kidding right, dry ice were I live in the hills ?

And by the way, all that over two days in the freezer stuff is nonsense. If it’s at x degrees cold then it’s x degrees cold, no matter how many days or hours it’s in the freezer

It takes over 24hrs for a crank or bearings to fully get down to temp for those for us that don't have dry ice.

I guess I could have told him to use a dremmel tool or die grinder and get it off that way, but many times there is no substitute for the right tool for the job

That works?

[mihylo33]

been using presses and mallets for years..... no problems?

[Mikel.Laundry]

the only reason im asking is why would i buy a tool im only going to use once. i dont do this ever and i cant rent tools and i was only looking for a solution to this problem with out the tool thanks

[Mark6299]

I give up. Do whatever you want, good luck and tell us how it turned out.

[KTM-548cc]

i can understand your hesitation of buying tools for a one time use but youve failed to look at the bigger picture. how you plan to get the cases back together ? could try the freezer/heat trick but i can almost assure you the crank will get half way in the cases and get stuck because its temp eqauls out with the bearing. then your only choice is banging the cases together with a hammer or using the bolts to suck everything tight. neither is a prefered method if you ask me but it will work. but you could break down and get a crank installer tool hahahahaaa

and why is your bearing stuck to the crank anyways ? dont know about the suzuki but on honda that indicates a spun bearing bore in the crankcase. thats bad news