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Bottom end assembly


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cases in the oven and crank and bearings in freezer makes everything easier.

+ 1 FOR SURE...this is how I put mine back together. Have the crank in the freezer like overnight, put that case in the oven set at about 225 for around 20 minutes. While the case is in the oven, start smearing that yamabond or equivalent and make sure everything is ready to go together(tranny, dowel pins, etc), bam cases are together minus a need for a tool:cool:

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Just an update. I just did mine. Case in the oven. Bake at 230 for an hour. that got the case to 200 deg. according to my IR temp gun. A temp gun really helps with this. Keep in mind though they are not accurate on a shiny surface such as a bearing. It will read low usually. Bearing in freezer dropped right in. Put it back in oven. Got bearing to only about 160 and pulled the crank out the freezer. Drops right in. NOTE* bearings should not be heated over 250 deg. Here is a good reference on a YZ 250. http://www.youtube.com/user/RockyMountainATVMC#p/u/17/kYX-bOG9vR4 You do not need to pull the tranny out of the case for just a crank. You leave the star detent on and the snap ring under the clutch basket and the tranny will stay together. Really nice if you dont need to do anything to the tranny!

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So you just leave the star detent on and the shift forks will stay in place?

I'm worried about using yamabond on a case thats 200 degrees fearing it will harden and crack after assembly and not seal.

I was thinking to just get the bearings installed in the case half using the heat/cold method. Then just heating the bearings only and not the case with a torch. Put the crank in the freezer overnight the night before and then they will just drop in together and the yamabond stays at a lower temp.

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Heat the cases just to install the mains. You can then put the clutch side case back in, get it up to temp then install the crank from the freezer. It will fall right in. let it cool off. yamabond both case halfs AT ROOM temp. Put the dowels back in after that. heat the left side main bearing inner race to 200 ish deg. Dont dilly dally to much. You will lose heat quickly. It should go right together if you got the tranny shafts in the bearings and did not lose to much heat. Have a rubber mallet or small dead blow ready to tap yhe case on if necessary. Now put in a few bolts. check the crank to make sure it spins freely and you did not side load the right side bearing. If the crank does not spin you can rap the right side of the crank with the soft hammer and it should center. Don't kill it, use your head. You don't want to kill your crank (alignment) or new bearings. Hope this helps.

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Hey everyone, I was wondering if it is possible to or if there is a good way to reassemble a bottom end without a crankshaft puller. I can't find one anywhere locally.

Thanks

I bought this crank installer tool from Rockymountainatvmc. http://www.rockymountainatvmc.com/productDetail.do?navType=type&webTypeId=140&navTitle=Tools%2FShop&webCatId=22&keyword=TUSK+CRANK+PULLER&prodFamilyId=17166 It sure does make life easy!!!

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