Spacer Size of the Wheel Hub


Bont Bearing SpacerWheel Hub
Here are many photos measured the space for the bearing spacers. Although it was the same size when saying roughly, it was not the same size strictly.


10.28mm and 10.26mm

GYRO MERCURY Violet F1 2007

10.16mm and 10.03mm


10.145mm and 10.105mm


10.22mm and 10.10mm


10.14mm and 10.09mm


9.94mm and 10.04mm
Zeroboard: The photos which surveyed the wheel hubs
HYPER-RACE 2008: Answer wheels hub problem
Inline Skating Notebook: Alu-Spacer (Mar. 3, 2010)

Outdoor wheels: Atom 1 vs Bont Highrollers?

by andr_gin (Dec. 15th, 2009)
The spacer problem is only the indirect cause.
I have rain bearings that need 0.3mm larger spacers, so for standard wheels (my Matter F0 100mm or the Rollerblade standard wheels) I need a 10.5 instead of a 10.2. When I first put the 10.2mm spacers in the wheels were spinning perfect, but after tightening wheels they blocked.

When I bought the Bont G4 I had the same problem again, but I found no spacers that were longer than my extra long spacers with 10.5

I wanted to use the G4 so I had to apply much force to get the bearings in. I even had to use a hammer to get them in (only touch them softly, but more force than you would have normally. The wheels were I had to use the most force started cracking, so I think I am sure this was the cause. Alex told me in a thread here or at (sorry do not remind) that you should use a 10.35mm spacer while 10.2mm is standard.

If you have standard bearings and standard spacers with 10.2 you might run into the same problems like I did, so it will be better to buy a set of larger spacers if you get some. Spacers that are too small will not damage the wheel but you will need more force to get it in so that the wheels do not block. Alex said that this is the cause. He suggested using a bearing press, but unfortunately you cant get one for 110mm wheels in Austra/Germany. If you have a shop selling them please send me a message

So here are the combinations that I have tested:
  • Matter F0 100mm with HTB Magic with 10.2 spacers: No problem at all
  • Rollerblade standard bearings with rollerblade standard wheels and 10.2 spacers: No problem at all
  • Movemax rain bearings with Matter F0 100mm and 10.2 spacers: wheels block
  • Movemax rain bearings with Matter F0 100mm or Rollerblade standard wheels and 10.5 spacers: wheels only spin about 15s, but when skating they are fast
  • Movemax rain bearings with Bont G4 with 10.5 spacers: wheels block. With much force or soft use of a hammer you will get the bearings in: wheels only spin about 10-15s getting better after a few km. Skates are fast, but 2 wheels cracked after 1.000km
  • Rollerblade standard bearings with Bont G4 and 10.5 spacers: No problem at all
  • Rollerblade standard bearings with Bont G4 and 10.2 spacers: Wheels spin for about 5 seconds if I put the bearings without the hammer method. When skating they are not slower, but you are definitely on the safe side with a larger spacer.
If you buy the G4 make sure that you buy a bit larger spacers (Bont says 10.35mm instead of 10.2mm). I decided to only buy the 10.5 spacers again with a set of G4, but change my rain bearings because they are making troubles in any combination, but it is sure that the G4 are also involved.
SkateLog Forum: Outdoor wheels: Atom 1 vs Bont Highrollers? Talk about a Bearing