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Crank Bearings won't go in

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Any tips? I am putting my 98 cr250 back together and for the life of me I cannot get the crank bearings in. This is about the 4th bottom end I've done (not on this bike) and I always sweat them in with no problems. This one for some reason doesn't want to work. I can get them in about 1/2 way and then it's done. Bearing not cold enough? case not hot enough? My local honda dealer said they are willing to press them the rest of the way for $, but in all honesty I cringe at the thought of them doing ANYTHING on my bikes (even just pressing in bearings).

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What are you heating the case with? I've never had a problem freezing the bearings and heating the case with a heat gun for about 5 min. Just gotta be quick and drop the bearing in square so it doesn't get cocked, and make sure there's no burrs in the case.

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i'm using a small propane torch and my house freezer. this is the first time i've ever had a problem. they are aftermarket bearings, but i've used this type 2 other times with no problems.

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You might want to measure the OD and compare to what came out. I have had some issues with China bearings

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heat the case in oven at 225 for about 10 min, freeze the bearings, then they should drop in. spec out the bearing first good luck

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Thanks, I'll have to give that a try today. I'll let you know how it goes.

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Let us know, I have never had to put bearings in yet, but I plan on rebuilding my bottom end next year!

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The oven is the best way. Just make sure you dont tilt it and have the other bearings fall out. I've never had one that stubborn.

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It's amazing how much you can take for granted. When I was younger and lived with my parents my dad had a garage and storage building filled with tons of tools. He also worked at a power plant so anything, and I mean ANYTHING, that needed to be done could easily be covered between the two (media blast, powder coat, press, ANYTHING). Now a days I live in another state and I'm slowly trying to grow my collection. But to get to the point... I wound up taking it to the dealer...what a mistake!:ride:

$70:eek::thumbsup::lol: Just to bash them with a hammer:mad:

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Let us know, I have never had to put bearings in yet, but I plan on rebuilding my bottom end next year!

doing a bottom end is not hard at all. having the right tools makes it even easier. this is about my 5th bottom end i've done and the only one that has ever given me trouble.

btw: when i was getting a beer out of the back of the fridge i noticed my temp settings were the highest for the freezer (trying to save $$$ anywhere i can). i wonder if the bearings weren't getting cold enough to shrink it to its full potential...like i said this was the 1st that has ever given me any trouble sweating in. oh well what can you do?:thumbsup:

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Wait till your wife/girlfriend isn't home and toss them in the oven. Set the oven around 300-350, leave them in for 10-15 minutes. The bearings will fall in. I've never had to freeze a bearing. Generally, when bearings are manufactured, they come with a tolerance range. The interesting part about the range is that its -0.0000, +0.0004 or whatever. That means, the bearing will never be too small but there is potential for it to be larger than another.

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