Crankshaft Bearings - Old Style Vs New Style
 

So I've had a few false starts with my rebuild. Finally got the right gasket set after getting mucked around by a supplier who insisted 2002 - 2011 are all the same. Now it seems I've got the wrong left crank bearing.

My bike is a 2011 EC 250 Enduro apparently. But I ordered a LH crank bearing from Haines to suit that year and it looks like this:

https://i.imgur.com/NVuyXf4.jpg

Yep, that's the new one installed and all assembly-lubed up - duh.

Problem is, the one that came out, and the one that fits my crank is the old style, like this:

http://i71.photobucket.com/albums/i1...psrwajauqd.jpg

(Shout out to RockefellerGG's rebuild thread - he's a legend).

I just assumed I got the new style because it superceded the old one. Nope - the crank is a completely different size where it fits into the bearing.

I can order the correct one from Haines (bit pricey but they have it in stock, and I'm guessing it's non-standard).

But I'm a bit worried that I have some kind of Frankenstein mix-and-match engine. Later model gaskets but old-style crank and bearing. Maybe other parts won't fit?

Any ideas, reassurances, or internet-hugs welcome, just want to get the bike back together so I can go riding again.

Cheers
Julian

How old is your bike? Are you not the first owner?

The older crank bearing is a 2 piece I think.. so you'll likely find the inner race is a press fit onto the crank itself.

See this https://www.youtube.com/watch?v=-5jKuyyrwWA

Also can't see in your pic. Does that bearing have a shield on it? Or is it just the polymer cage I can see.. Worth while removing the seals if the ones you ordered have them.

Hello,

What is the number on the older bearing ?

You can get the bearings and seals at - Simply bearings.

All top quality stuff, good prices.

The "old style" (roller bearing?) bearing has a "floating" (or independent) race that is pressed onto the crank. The "new style" (ball bearing) has a fixed race in the bearing. You need to remove the race from the crank nose if you want to go from the old style to the new style.

Also, I believe that the general consensus (from the old days) was that the "old style" roller bearing was preferred as it allows lateral float, whereas the ball bearing doesn't. However, I think that was preference based on historical precedence, and I'm not sure if there is any basis in fact that one bearing is better than the other. Although if there is evidence one way or the other, I would like to read it.

Awesome thank you that makes sense, the inner race is on the crank. Regardless which bearing I use I'll need to remove it, so I'll use the one I have (new style).

In my pic that's just assembly lube on the bearing, it came without seals.

Now to get the inner race removed... that video is helpful but might be a job for the shop.

My bike is 2011 with apparently only 140ish hours on it when I bought it. I assume either it got fitted with the older style bearing from new (unlikely?), or the bottom end has been rebuilt before. No biggie, it's getting a complete rebuild anyway.

Cheers all.

Roller bearings handle greater loads than ball bearings. They do however require accurate alignment (races must be parallel to each other). They are also noisier, but their real advantage is easy engine assembly. The rollers slide over the inner race, no possibility of "pinching" the crank bearings on assembly.

Use temperature differences to assemble an engine with ball bearings. Warm cases with cold bearings to install the bearings in the cases. Warm cases and warm bearings to slide over a cold crank.