Wheel Bearings front and rear

[bobajob]

Hi I think this has come up before but I can"t find the thread.

I'm stripping the alloy wheels for powder coating, I've got one of the front wheel bearings out by pushing the central spacer to one side and drifting it out. Should I be able to do the same with speedo drive side? It appears to have some kind of cover.

I'm completely at a loss with the rear wheel, there appears to be a central spacer but I can't push this to one side to drift the bearings out in the usual fashion, is there a trick to this or should I just try harder! I'm assuming I should remove the bearings, anyone have any opinions on getting the wheels blasted and powder coated with the bearings in place (masked obviously)?

Thanks for your help

Bob

[danomar]

Remove the speedo gear from the wheel first. It will make the task much easier and prevent possible damage.

['It must be a .....']

Hi, I've never done 350 front wheel bearings, but just to avoid any confusion don't attempt to remove the speedo gear from the wheel as you'll wreck both the wheel and the drive in the process.
I'm certain danomar meant the driven speedo gear and it's housing (the casting you attach the cable to) but I thought it should be clear.
As to the tight central spacer you need to lever it to the side.

As it's tight it could be slightly too long and will be putting a load on both bearings if they are fully seated in the shoulders of the hub.
When I first change the bearings in a Grimeca hub (and sprocket carrier) I always measure the distance between the shoulders where the bearings seat to make certain the spacer is the same length as not load the bearings once fitted. So far all spacers I've encountered have been slightly too long (as much as 1.5mm); thats on 4 bikes to date and a new hub I got from Harglo years ago was so tight I couldn't turn the bearings at all.
Having done this to the spacers, used quality sealed bearings, regularly greased the oil seals and used a pressure washer with care I've never had to replace any of the wheel bearings.
Hope this helps, good luck, Ian

[bobajob]

Thanks guys, back to the shed for another go!

[bobajob]

Right front wheel sorted.

Still confused by the rear. It doesn't look like a space between the bearings (I've gently run a screwdriver up it's length and can't feel the join between the spacer and the bearing) rather one wide bearing unit. I'm sure this can't be the case but would like to understand who it goes together before I start hitting it with a hammer and drift!

Anyone know on an exploding diagram online? Or can someone confirm how the bearings mount in the hub?

Thanks to everyone for helping.

Bob.

[EVguru]

Remove the speedo gear from the wheel first. It will make the task much easier and prevent possible damage.

DO NOT DO THIS!

Those speedo gears are made of pure unobtanium and there is simply no need.

Scrape round the inside of the hub to remove any burrs and apply a bit of heat (hot air gun is nice and controllable). Just too hot to hold your hand on is enough. I've not had trouble getting bearings out and I must have done 20+ Morini wheels.


The rear bearing spacer is spigoted on both ends to reduce the bearing bore to suit the spindle. Make up a drift with a pilot diameter the same as the spindle and a secondary diameter to suit the bearing ID.

[bobajob]

Thanks Paul, front sorted without removing the speedo gear. I'll follow your advice for the rear.

Bob

[3potjohn]

When i did mine i used a large rawlbolt to grip the bearings and poured hot water over the hubs before tapping them out- then cooled the new ones before tapping them in. Compared with the taper rollers and "wedding band" spacers on BMW wheels its a doddle.Not sure about the weather proof factor of the Morini bearings so i used stainless sealed bearings.

[bobajob]

OK, so thanks to all the advice on this thread I've managed to strip both wheels. For the rear I ended up separating the inner and outer races so I could get the bearing out in bits and hen knock the other bearing out complete.

So now ordering replacement bearings. Going to get shielded (the originals were unshielded) but what does the C3 designation mean and do I need this bearings with this designation?

thanks

Bob

[EVguru]

I always use sealed bearings and discard any felt shields.

A C3 bearing has increased internal clearances. I've found some wheels with them, but most with standard bearings.

I usually buy from www.simplybearings.co.uk

[bobajob]

Thanks Paul,

Just found the on the simplbearings webs site:

Applications like motorcycle wheels or bicycle wheels do not require C3 rated bearings.

so I'll go with the standard bearings......