sealed wheel bearing snafu

So I took Ryan's advice, disassembled my leelu spoked rear wheel, and took it to a bearing shop. They measured it with calipers, and came up with a bearing, SKF 6001. However, they said that this bearing was too small; the balls were too small, it was designed for extremely light loads, and that it would fail on me without question if I were to put them in the wheel. The dimensions on the 6001 were 28mm OD, 12mm ID.

They recommended a 6202, which has a 12mm ID, but a 35mm OD. The OD on the part of the wheel I have to put them in is only 33mm. The 6200 has a 30mm OD and a 10mm ID, but they said a 10mm axle was too small, and would break. They sent me to a machinist to ask what axle was thick enough not to fail, blah blah blah and the machinist said it was impossible, and that I should stick with the cup and cone, or that I would die on the 6001 bearings when they failed on me while riding.

I've searched the topic, and when Paz posted about converting a wheel over to sealed bearings in 2007, he shows a picture of what appears to be a 6001 bearing. It also appears to have a 2 letter suffix that I can't read in the picture, but who knows if that matters or not.

Here's my question; those of you who have converted cup and cone wheels to sealed bearings, what bearings did you use, and have they ever exploded or failed on you?

Re: sealed wheel bearing snafu

Peugeot's use stock on the rear wheels a 6200 bearing, and I have puch that has the same setup in the rear. Never a problem with either one.....


Re: sealed wheel bearing snafu

Here's a pic of the one I installed on my snowflakes. 6001Z bearings with an adapter around the bearing.


Re: sealed wheel bearing snafu

The suffixes relate to whether the bearings are sealed or shielded. Usually S for sealed and Z for shields. One letter for one sided and two letters for double sided.

Re: sealed wheel bearing snafu

Yep all you need is the 6001 bearings the adapter shim and the bearing spacer/axle support.

I used bearings with seals (sufix)

I have been running the 6001 for over a year now without issue in the front and Motomatic has been converting a number of wheels without issue.

Also note that puch rear wheels with sealed bearings also use 6001 bearings from the factory.

Re: sealed wheel bearing snafu

Just so that we're all on the same page, here's the picture that Paz posted that I am referencing:

and here is the thread he posted it in:

After looking at the picture some more, I've concluded that it could be any one of several bearing numbers.

But I was looking at the spec sheets from SKF, and the 6200 has the same static and dynamic load ratings as the 6001. Why would the bearing guys say that the 6200 was safer because it had bigger balls in there if the load ratings are the same?

Their argument was that the static load rating of 530 pounds of force was way too low. For something "my life depended on" they said we should overbuild by at least twice as much, if not three times as much. Combined, the moped and I weigh 300 lbs. And it's not like I'm going to be just sitting on the moped much anyway. As soon as it starts rolling, the load limit goes up to 1,220 lbs.

Re: sealed wheel bearing snafu

Sweet action. That's the info I needed!

Re: sealed wheel bearing snafu

That 530 load rating they cited may very well be underated itself. Further with 4 bearings on a ped would the rating be 4X 530?

Re: sealed wheel bearing snafu

If you have ever seen how small the wheel bearings are on cars and trucks for the weight you might come away with a better perspective

Re: sealed wheel bearing snafu

yeah, the bearings are already rated at a safety factor of four, plus there are 4 bearings supporting you on the moped.

i dont know what bullshit bearing shop you went to, but they are wayyy off. 6001 bearings are way stronger than you could ever need.

Re: sealed wheel bearing snafu

B-R-C Bearing Co. You guys are totally right about the weight being on 4 bearings and not just 1.

I think I'm going to go with shielded just for shits. The specs for the shielded 6001 are just the same as all the other 6001 variants, and it'd be nice if the balls didn't fly out when they do eventually fail, though I talked to my cycle mechanic friend, and he said that I'll know the bearings are going bad way before they blow. Apparently you get a lot of side to side play on wheels where the bearings are going bad. I definitely learned something today.

Re: sealed wheel bearing snafu

Those little rubber shields will not retain the balls if the bearing fails. And yea if you check your bike every now and then bearings going bad is a pretty easy thing to spot.

Re: sealed wheel bearing snafu

Here's a question: the bearings are rated for static and dynamic load, but what about their maximum speed rating?

The only reason I could see to suggest a different sealed bearing unit with similar inside and outside diameters would be the different speed at which differently-sized bearings rotate.

So, was the bearing shop trying to say that you would spin a 6001 so fast the little bearings would heat up, boil away their grease, and then die a horrible heat-death on you?

That actually sounds plausible (if your wheels were half their size and you went many times faster).

Re: sealed wheel bearing snafu

According to the SKF spec chart, the reference speed for these bearings is 60000 RPM, and the limiting speed is 30000 RPM.

Now to machine some axles and shim the bearings in!

Re: sealed wheel bearing snafu

Guess you did notice the little bit on information I posted in one of the replies.

Puch sealed rear wheels use 6001 bearings, you will have no issue using them for your front wheel.

Re: sealed wheel bearing snafu

just realized I have a set of sealed bearing puch spoke wheels. so, where do I get the bearings in California?

Re: sealed wheel bearing snafu

^ there is hundreds if not thousands of bearing shops in cali. <>

Want to post in this forum? We'd love to have you join the discussion, but first:

Login or Create Account