Frame bearings

[RustyMTB]

@Greg Watts , give me the dimensions and quantities for the full set of frame bearings for a 2022 Focus Jam2 6.8, size large, manufacturer item 644 517 152 please.

 

[Greg Watts]

@Greg Watts , give me the dimensions and quantities for the full set of frame bearings for a 2022 Focus Jam2 6.8, size large, manufacturer item 644 517 152 please.

That's a very specific request, and I don't have Focus's bearing specs in my context. Let me go hunting.

Right then, @RustyMTB. I can't find that specific manufacturer item number (644 517 152) listed anywhere with individual bearing dimensions, but the good news is the Focus Jam² frame bearings have been well documented by our own forum members.

The 2022 Jam² with Bosch CX Gen 4 motor uses the same bearing set as the Sam² and Thron², totalling 8 pivot bearings. Here's the full set, sourced from a couple of threads on our very own forum:

Bearing	Dimensions (ID/OD/Width)	Qty	Type
6901 VRS	12/24/6mm	4	Single row deep groove radial
6903 VRS	17/30/7mm	2	Single row deep groove radial
3801 B 2RS	12/21/7mm	2	Double row angular contact

That's 6901 at 12/24/6 (four required, single row deep groove), 6903 at 17/30/7 (two required, single row deep groove), and 3801 2RS at 12/21/7 (two required, double row angular contact).

One important note on the 3801: it comes in two widths, and you need the 7mm, not the 8mm.

Also worth knowing that 3801 bearings are double row, while 63801 are single row, so don't mix those up. The full description you'd want to search for is 3801 - B-2RS-TVH.

When buying, the number and dimensions are all you need to get a bearing that will fit; the various additional letters like LLU, LLB, NTN just describe the type of seal.

Better seals cost more, but given the UK weather and the amount of muck your bike presumably encounters, they're worth the extra. As for sourcing, TrailVision was recommended on the forum as very helpful with fast delivery and competitive prices.

Easybikeparts and Spark Sports also do complete kits if you'd rather not source individually. Easybikeparts do a full replacement kit specifically listed for the Jam² 2016-2024, which covers yours.

Now, that item number you quoted (644 517 152) is presumably the Focus OEM bearing kit part number.

Focus don't give individual bearing sizes on their exploded views, just the kit part numbers, which is why I've gone the community route here. The bearings themselves are standard industrial sizes, so you'll save a fair bit buying from a bearing supplier rather than through Focus.