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I was ready to put a motor back together when I noticed they sent the wrong bearings with the Bottom rebuild kit, crank, seals and bearings. So I went locally to a place that sells this sort of thing. They are known to stock lots of bearings.  They did not have them so I made a mistake of letting them order them, because they said they would have them in the morning. But a week later they arrive. I could have ordered them myself sent to my door by then. But after opening the box, I see they sent the right size but they came sealed. You can pop out the plastic seals and there seems to be no difference. Any reason not to use these bearings? I'll never go that route again. Lesson learned

Edited by 1gr8bldr

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Just pop off the seal(s) so it matches the bearing you are replacing. Some Honda trannies pressurize the shafts with oil from one end and use a bearing with a seal to insure oil goes into the shaft.  Main bearings are often special clearance so OEM is recommended.  Some  have a needle bearing for one shaft in the tranny that is part of the case, aftermarket bearings are available .And Honda likes to use special sizes that are based on standard metric bearing e.g. steering head bearings. 

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FYI a good counterman at a seal and bearing shop can look at the mfr number on the bearing and tell you more than the sizes.  The clearances are not so much to allow for up and down movement as they are to allow for misalignment (in a nutshell wider channels when talking ball bearings).   

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4 hours ago, 1gr8bldr said:

I was ready to put a motor back together when I noticed they sent the wrong bearings with the Bottom rebuild kit, crank, seals and bearings. So I went locally to a place that sells this sort of thing. They are known to stock lots of bearings.  They did not have them so I made a mistake of letting them order them, because they said they would have them in the morning. But a week later they arrive. I could have ordered them myself sent to my door by then. But after opening the box, I see they sent the right size but they came sealed. You can pop out the plastic seals and there seems to be no difference. Any reason not to use these bearings? I'll never go that route again. Lesson learned

likely you will be fine but typically bearings come with a CN clearance, most bearings used on crankshafts use either C3 or C4 (the next two sizes greater clearance) due to the clearance lost by having an interference fit on the inner and outer race.

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They cost me $75 so I would like to use them..... but just a hint of question and I will not risk having to tear it back down

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Pull the plastic and it's fine! Bearings are bearings if there the same size whether in grease or oil just clean grease out of the case of bearing otherwise oil won't enter til grease is gone unless they were oil filled already then just pull the plastic case.

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I wouldn't use them. In my search for bearings for my boy's KX100, I stopped at a local bearing supplier. He said he could order the right size, but not necessarily the correct one. He showed me the numbers etched on the outer race and said that those types of bearings have very special load and clearance tolerances etc and that he couldn't sell me them in good conscience for fear of early failure. I thanked him profusely for his honesty. He also gave me a good schooling on good brands and countries etc. He was speaking of all the other bearings in the case. Not the main bearings, since those came with my kit. But I assumed his advice would've applied to all of them.

 

I'm all about after market stuff. But bearings inside the motor? I'm all OEM. Bearings are not just bearings.

 

Just my worthless opinion...

 

 

 

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bearings are definitely not just bearings, ITs possible that the supplier got you bearings with the right clearance, if it was not CN it was likely stamped on the box as it proper clearance, I am currently running FAG bearings with C3 clearance in my bike since OEM prices are ridiculous. 

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9 hours ago, 1gr8bldr said:

They cost me $75 so I would like to use them..... but just a hint of question and I will not risk having to tear it back down

you should be able to verify that you have.  it is those c1, c2, c3 things that make the difference.  the cases do more moving that you realize and allowing for some misalignment as things flex is what that is all about.  you can probably get the brand and numbers and verify that with the mfr if it gets to that.  like wild says,  what is on the bearing or the box?  I made need drying off on the radial vs axial clearance,  but as I recall the cn that wild mentions is "clearance normal" and c1 and c2 are slightly tighter.  c3 being slightly looser thus making up for the squeezed down affect you get from a press fit.  you wonder when they come out with the crankshaft or drop in with little heat how much that is going to affect it's running clearances though.  

Edited by ossagp
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I like this thread. If I can get away with NOT buying oem at any time I do it. After seeing this thread, I'm going to do a little more research on them re tolerances. It'd be nice to find an alternative. Where I worry is that the distributor told me he couldn't look that info up, so I wouldn't know where to begin.

 

I did find some great prices on oem at partshark(thanks TurboDan). But their shipping prices are obscene, almost negating my "savings"

 

 

 

 

 

 

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Bearings taken from the crank are TM83/28JR2C4. Bike has been rebuilt before. The bearings they gave me EiB19 63/28 2RS c3. Everything mics out the same. Only difference I see is the original or before bearing has more taper on the outer corners. Somebody talk me out of this. They are in the freezer. 

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They cost me $75 so I would like to use them..... but just a hint of question and I will not risk having to tear it back down

**Edit** Nevermind if you read the original reply, those weren't the same bearings as you have.

 

Who is the manufacturer?

 

The C3 will run slightly tighter than the C4 bearings.

 

 

 

 

 

 

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Bottom end is back together. Found a bad blind  bearing on the way back out on the clutch side so on hold until bearing arrives

Edited by 1gr8bldr

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