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Discussion Starter · #1 ·
Where do i find some better crankbearings for my cag 47cc engine, like some skf that are more freespinning.
 

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If not ebay, automotive stores, or generally online. I forget the measurements but somebody else could chime in. Once you know the measurements just look those up online. You can get sealed bearings but remove the seals and clean the grease out. They need to be open bearings. SKF is really nice, although I have used other good quality bearings
 

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Discussion Starter · #3 ·
If not ebay, automotive stores, or generally online. I forget the measurements but somebody else could chime in. Once you know the measurements just look those up online. You can get sealed bearings but remove the seals and clean the grease out. They need to be open bearings. SKF is really nice, although I have used other good quality bearings
I May have found some skf but they are sealed, isnt it hard to get the grease out without breaking the bearing?
 

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Look for 6202 open bearings. That is the correct size and bearing. Like I said you could get sealed ones and then remove the shield and clean out the grease.
 

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No it doesn't have to be perfect. I used brake cleaner and then just sprayed in some two-stroke oil afterwards. If you don't even want to mess with that find the open bearings
 

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why do they need to be open bearings and not sealed bearings? Essentially, wouldn't the sealed bearings be better?
 

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No, the oil/gas mix do the lubrication job in an 2 stroke engine.
Get some skf 6202 C3 / tn9 that are the correct bearings for crankshaft. I have them if you need.
 

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Right on, c3 is the best. But ANY nonChinese bearings in the 6202 size is best
 

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Yeah, but sealed bearings are already pre-lubricated, and can handle the RPM and heat generated. So, why undo that just to have the same job done by something else?
 

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The lubrication in a closed bearing will not last very long and then the bearing run dry.
Trust me every 2 stroke engine run with open bearings. Also a 18k rpm bzm engine and it works.
 

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You can not use sealed bearings for the internal crank bearings...

The oil that you mix with the fuel is responsible for lubricating the entire engine if the bearings are sealed how is the two-stroke mix going to get into the bearings and keep them lubricated?

Also take this note down!

You can't just slap any bearing into an engine you should be using deep grooved crank bearings if you decide to cheap out and use regular bearings your engine will quickly develop a lot of end play and destroy itself if it is heavily modified.
 

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What's your poison? Mine is 40:1
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You can not use sealed bearings for the internal crank bearings...

The oil that you mix with the fuel is responsible for lubricating the entire engine if the bearings are sealed how is the two-stroke mix going to get into the bearings and keep them lubricated?

Also take this note down!

You can't just slap any bearing into an engine you should be using deep grooved crank bearings if you decide to cheap out and use regular bearings your engine will quickly develop a lot of end play and destroy itself if it is heavily modified.
Aren't all 6202 C3(non Chinese) deep groove?? I'm only saying because everyone I've looked up, Japanese, Canadian, USA doesn't matter, they have all been deep groove as a 6202 C3.
 

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Discussion Starter · #15 ·
The lubrication in a closed bearing will not last very long and then the bearing run dry.
Trust me every 2 stroke engine run with open bearings. Also a 18k rpm bzm engine and it works.
Just pulled out my bearings and they were both closed, have no idea if it came from the factory that Way… so im just gonna change it
 

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Just pulled out my bearings and they were both closed, have no idea if it came from the factory that Way… so im just gonna change it
Yikes, I've pulled the part probably 15 engines and not one has sealed bearings. They are supposed to be open. Like previously said, the oil in the two stroke mix lubricates the crank bearings.
I used sealed bearings on one engine because at the time I could not find a set of open bearings to get shipped to me decently quick. I pulled the seals out and cleaned the best I could and then lubed with two-stroke oil before installing
 

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Just pulled out my bearings and they were both closed, have no idea if it came from the factory that Way… so im just gonna change it
If they are a decent brand, just pull the seals and use brake cleaner or carb cleaner to clean them out and then leave them up well with 2-stroke oil. If you don't want to do the labor then just find some open bearings, 6202 c3 open
 

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Can't wait. I have a quick feeling they will last a while but eventually heat will dry up the grease and seize, but probably have pleanty of ride hours on it. Thats my official guess.
 

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i don't think heat will dry up the grease. the seal may take some damage before that. in my experience with sealed bearings, the rpm isn't a big deal, as long as heat is managed. technically, the intake air will cool the bearings. open bearings are usually cheaper though.
 
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