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Gp flywheel bearing

PostPosted: Sun Nov 19, 2017 9:19 am
by al pushpak
Hi, just wondered if there was a way of removing this bearing intact as I want to replace the small mag seal & obviously this bearing is in the way :? I have tried in the past but have never been successful & have always ended up having to fit a new bearing :( any info greatly appreciated ;)

Re: Gp flywheel bearing

PostPosted: Sun Nov 19, 2017 9:37 am
by dickie
Yes, I use a knife edge bearing puller. EBay for about 20 quid or so. It has loads of other uses too.

Re: Gp flywheel bearing

PostPosted: Sun Nov 19, 2017 9:41 am
by al pushpak
Hi, that sounds like a plan ;) do you have an item number or a link? thanks ;)

Re: Gp flywheel bearing

PostPosted: Sun Nov 19, 2017 9:42 am
by dickie
One of these

https://rover.ebay.com/rover/0/0/0?mpre=https%3A%2F%2Fwww.ebay.co.uk%2Fulk%2Fitm%2F201908761724

I'm sure it's not snap on quality but I've been using mine for 10 years or so on all sorts of bikes and it's still ok. Can't grumble for 20 smackers

Re: Gp flywheel bearing

PostPosted: Sun Nov 19, 2017 9:45 am
by Tractorman
I remove the circlip and seal, clean out the grease and heat the mag housing with a blow lamp (not excessively) and then with a gloved hand bring the mag housing down on a block of wood. There will be several other method but this works well for me.

Re: Gp flywheel bearing

PostPosted: Sun Nov 19, 2017 9:52 am
by al pushpak
That looks spot! Having never seen or used one before could you give me the basics on how this pulls a mag flange bearing out? Sorry to be a pain & a bit thick :P

Re: Gp flywheel bearing

PostPosted: Sun Nov 19, 2017 9:53 am
by al pushpak
Thanks tractor man ! never thought of trying that ;)

Re: Gp flywheel bearing

PostPosted: Sun Nov 19, 2017 10:11 am
by dickie
al pushpak wrote:That looks spot! Having never seen or used one before could you give me the basics on how this pulls a mag flange bearing out? Sorry to be a pain & a bit thick :P


Not as thick as me. I didn't read your post properly and thought you meant the part that stays on the crank.

Sorry

However, I have removed the part you're actually asking about by using parts of a silent block tool as a puller. I'm sure I have a photo of it somewhere. I'll look for it.

Re: Gp flywheel bearing

PostPosted: Sun Nov 19, 2017 10:21 am
by dickie
Not a particularly helpful image but I used a con rod holding tool on one end then the bolt and nut from the silent block tool and wound it out.

Best to tighten a little then heat, then retighten. Repeat cycle until it's out.

https://www.flickr.com/photos/151764784@N06/38460131896/in/dateposted-public

Re: Gp flywheel bearing

PostPosted: Sun Nov 19, 2017 11:29 am
by Scooterdude
The way I do it is to remove the circlip and large seal then set up my camping stove light it and place the mag housing on top and place a large washer over the side with the small seal to keep the heat in, go away and do something else for ten minutes the bearing and bearing spacer will either drop out completely or have slipped down the bore of the housing requiring nothing more than a gentle tap on a piece of wood to remove..... then quickly remove the small seal and replace with a new one, drop in the bearing spacer and new bearing while it's still hot, new large seal and circlip.

The only time I came unstuck as it were using this method was when replacing the bearing in a Scootopia mag housing, no amount of heat would expand the housing enough and I had to resort to using a hammer and socket to tap it home.

Re: Gp flywheel bearing

PostPosted: Sun Nov 19, 2017 1:45 pm
by Adam_Winstone
Camping burner with small steel plate does it for me too, very simple, no special tools, no damage to parts.

Re: Gp flywheel bearing

PostPosted: Sun Nov 19, 2017 4:26 pm
by CHRIS in MARGATE
And then freeze the new bearing. All drops in nicely.

Re: Gp flywheel bearing

PostPosted: Sun Nov 19, 2017 4:43 pm
by al pushpak
Hi , thanks for all your replies, will give the heat & tap on the wood method a go, if that doesn't work I've got an engine mount puller I can use. cheers guys ;)

Re: Gp flywheel bearing

PostPosted: Sun Nov 19, 2017 6:45 pm
by Phil D
dickie wrote:One of these

https://rover.ebay.com/rover/0/0/0?mpre=https%3A%2F%2Fwww.ebay.co.uk%2Fulk%2Fitm%2F201908761724

I'm sure it's not snap on quality but I've been using mine for 10 years or so on all sorts of bikes and it's still ok. Can't grumble for 20 smackers


Useful bit of kit I've been meaning to buy one for ages but not seen one as cheap as that Thanks!

Re: Gp flywheel bearing

PostPosted: Mon Nov 20, 2017 11:43 pm
by HxPaul
Got the last one yesterday Phil.

Re: Gp flywheel bearing

PostPosted: Tue Nov 21, 2017 2:51 am
by Fast n Furious
Wait till the wife's gone out.
Crank the oven up to gas Mk9.
Switch the extractor on to eradicate any tell-tale evidence.
Place mag housing in an old baking tray.
Cook for 30 mins.
Extract with the old oven gloves and bang it over a solid peace of wood to release the bearing (don't do this in the kitchen. I did, but I think I got away with it)
Turn off the oven and leave the door open so it cools before she gets home.
Get rid of all evidence.
Job's a peach.

Re: Gp flywheel bearing

PostPosted: Tue Nov 21, 2017 9:16 am
by HxPaul
Fast n Furious wrote:Wait till the wife's gone out.
Crank the oven up to gas Mk9.
Switch the extractor on to eradicate any tell-tale evidence.
Place mag housing in an old baking tray.
Cook for 30 mins.
Extract with the old oven gloves and bang it over a solid peace of wood to release the bearing (don't do this in the kitchen. I did, but I think I got away with it)
Turn off the oven and leave the door open so it cools before she gets home.
Get rid of all evidence.
Job's a peach.

The trouble with heating it up in an oven,is that it heats the bearing as well,making it harder to get out.

Re: Gp flywheel bearing

PostPosted: Tue Nov 21, 2017 10:32 am
by EddieStone
I've always heated mine up on one of the cooker rings.

When we got a posh new cooker I put a sheet of foil on the hob, then put the mag inner face down on that.

If your spit sizzles when you spit on the flange it's ready. Use a good oven glove and bang it down on a flat piece of wood. The bearing should drop out fairly easy. Or at least mine has.

Obviously remove the circlip and seal first. Clean as much of the grease out of it as possible as well.

Re: Gp flywheel bearing

PostPosted: Tue Nov 21, 2017 10:53 am
by Phil D
Old camping stove for me ,not brave enough to use cooker after the unfortunate incident with the tank/ tumbledrier :oops:

Re: Gp flywheel bearing

PostPosted: Tue Nov 21, 2017 1:07 pm
by al pushpak
thanks for all your input, certainly gives me plenty of options ;) just curious about the oven/camping stove method, does this damage the bearing ? as in my case I want to re use it once I've replaced the small mag seal. thanks again ;)