Modern Vespa

Hi all

I've taken out the steering tubes to replace the notched head bearings, but the first bearing I've had a look at is completely stuck on. I've tried to knock it free with a center punch which seems to be the common method but it woudn't budge. I've removed the bearing cage with an angle grinder because it was getting pretty bashed up after the hammering with the center punch.

I've also tried cutting into the race carefully with an angle grinder to see if I could free it, but still no joy and I don't want to cut any further in case I go into the steering tube itself.

My next thought is to let it sit in some penetrating fluid for a day or two and then try again with a new sharp cold chisel, if that doesn't work then weld on a plate to give some purchase and get a long pipe on it and try and use that to turn it and break the grip. Hopefully the penetrating fluid, some heat from the weld and some leverage might move it.

Anybody who wants to see what the inner race of a notched bearing looks like after a gonzo tweak, have a look below!

a old trick was pour coke on them and leave over night

dremel tool with a metal cutting disc is the way to go. cut a relief on 1 side then cut 180 deg from that cut and it should fall into 2 pieces. That is how I did 2 sets of them for customers so far.

if your careful you should not get into the tube but if you get a little it won't hurt it.

Cheers, hadn't thought of a Dremel, my brother has one, will give it a try.

I see a lot of rust and no grease.

Agreed, all my grease has been cleaned off, but they were dry when I bought the bike so probably not in a good state from then.

They will be well lubed when I manage to replace them. Will report back with progress.

I assume as you mention weld that you have a welder if it's a arc or mig then just put some weld onto the bearing it will then expand and you will be able easily to knock / pull it off.

I have access to a MIG. It struck me that the one thing I should do before any welding is disconnect the wheel velocity sensor so I don't fry it!

But will try dremel/cold chisel tonight first..

I assumed stem was off the bike, if so sensor will not be harmed .When doing any welding on vehicals i always disconnect battery though. I 've just noticed you have? hagon shocks if so what spring rate are you using 14kg ,16kg. Do you carry a pillion passenger.Last year i spoke with Hagons and they said they did'ent do shocks for the fuoco . I'm thinking of removing some koni's i've got presently fitted as the spring rate is far to strong but there still better than the carpy o/e piaggio.

Just tried my brothers battery dremel. Not a chance!
Would be interesting to know what kind of dremel does go through the hardened steel...

Next stage is to try welding a lug onto the race and seeing if the heat and leverage will get it off...

These things are never easy eh??

I'm sorry but I can't remember what spring rate my Hagons are. If you look at my previous threads they were made up specially for me by Hagon who needed a prototype bike. Hagon have said that you should tell them what weight you are and if you carry a pillion often and they'll tell you the best spring rate. Sorry can't be of more assistance.

a powered dremel with a cutting disc, the battery ones don't have enough umph to spin the cutting dis at a high rpm for a long period of time. you can't force it just let it do the cutting.

Just put a few blobs of weld on the race this will expand the race and you will be able to knock off the bearing easily. OR just use your mains powered grinder don't be too bothered about scratching the surface of the steering stem,infact when you get near the stem you will see the bearing were your grinding start to go blue as you get near to the inner portion. The heat generated will probably make the bearing loose anyway. Thanks for the hagon info will get onto them again.

Provided you have removed anything which is not steel then heat applied directly to the race has got to be the answer. There must be a gap where the soft collar sits behind the race so you can attack that with a chisel once plenty of heat has been applied. I agree that a high speed Dremel with metal cutting disc will work and I did this recently with a race which was inside a car hub and therefore more difficult. That needed plenty of heat too!

Just had the time to watch a couple of youtube videos of people cutting races with dremels..

Can see that a weedy battery one isn't going to cut the mustard. A guy up the street is going to lend me a mains one tonight, I'll give that a go..

The video below shows a guy getting through a beefy bearing in about 6 mins, which is confidence inspiring..

I wonder with all the effort, you find the part on Ebay?
I have seen them listed, not sure there are any right now.
If I see any will come back here and post.

Keith,
Marietta, GA

to remove the bearing 'cup' if it is stuck, just run a bead around the inside . the bead will shrink the cup , it'll fall out. done it 10 million times, well , many. all methods as listed by others will work, when using a cold chisel to cut through the remaining ring make DAMN sure to protect your eyes! i've had to remove shards of steel when doing this chore on trucks and dozers etc. the video shows a coupla things that made me cringe, he directed the sparks, ie steel particles INTO the motor instead of away from it, and NEVER smite an overhung shaft without some support, the load on the inboard bearing was enough to make my eyes water, close to tears!

He even put a tag that says use eye protection. Glasses in no way are designed to protect the eyes. Geez. I know what you mean triker.

best way is heat and a hamer with a dremel you could demage the leg

The mains powered dremel allowed me to cut an accurate notch into the bearing race and then crack it with a new cold chisel once I was deep enough, no damage at all to the steering rod underneath.

You can see the crack which released the tension on the race in the attached pic. Interestingly it didn't run straight up the line of the dremel cut.

I managed to hammer off the other race without cutting, it needed a 1 x 12" Cold Chisel and a hell of a lot of hammering but finally managed it.

The bearings are KBC 32008XJ in case anybody is interested. I have SKF replacements.

I'll have to get some new bottom seals, think that these will do the job..

https://www.123bearing.co.uk/seal-32008-XAV-NILOS.php

Than to get the outer races off and start thinking about putting it all back together. I'm sure that there will be a few hicups along the way.....

Thanks for all the advice so far, super helpful as always!!

i hope you got it off by now!, but if not take that angle grinder, then ( wearing safety glasses) and grind a flat on that brg, don't expect to get all the way through, the heat of the grinding should have loosened it's grip, plus that area is now thinner and softer so a cold chisel ought to split it. have you got the cup out yet, they can also be a nuisance to get out. if you do have to resort to using a welder be sure to unplug the computer modules, they might not like the 'electron-bumping' that goes on. and hook the ground as close to the brg area as you can. looks like your'e succeeding in you'r endeavor! don't forget to heat the brg before installation, boiling water usually does it. if you use propane not too hot, only till 'spit sizzles' when you spit on it. the brg outer cup and race are usually sold as a matched pair, so don't fit a new race with your old ring! catastrophe will ensue!

I've welded up a little tool to help me try and easily remove the outer cup. Just need to adjust it slightly to fit the diameter of the cup which I'll do tomorrow night. Will report back on how that goes.

Unfortunately the bike is in my garage, nowhere near any power supply, so won't be able to do any welding.

I did see that bead welding technique done in a youtube video today so its an interesting tip!

Did'ent watch the video but the photo alone say's it all what a plonker ,grinding with all the throw off going into the armature.

and there was a reasonable amount of dust and grit thrown off when I cut the slits in my bearing..so I'd imagine all that would have gone into the motor...it would only have taken a second to mask it off!

To true. Anyway glad you got the race off at last.

Hi all, just thought that I'd report on progress..

The bearing cups proved to be just as seized as the inner races. I knocked up a little tool to see if I could budge them but snapped the welds.

So I made up a much bigger version with much more leverage which broke the seal and started to move them.

I then knocked up a weight on the shaft to turn it into a slide hammer so I could direct the force straight down rather than laterally.

I've put some pics below.

I also have the replacement nilos seals for the bottom bearings, so now to start reassembly...

I find a 3 jaw slide hammer and an acetylene torch work well.

hi desq, i just looked at your original photo again. is that a 'repair weld' on the right with a 'chunk' welded across the weld? it's not good to weld on a critical steering part unless the repair person knows what he's doing. you'r tool worked for you, but if the brg cup had been sunken further in you'd have pivoted the 'cross piece' so as to thread it through the cup. ( i have a similar extractor with that cross piece pivoted and the ends tapered . even so if the cup was in a 'blind' hole with no way to get the cross behind the cup the best, ( and only way) would be to run a small bead around the inside to shrink it out. you'r doing good so far! boy! that old brg cup is really rusty! the previous owners/ mechanics didn't waste much grease on that!

Update..

I've inserted the bearings and cups using SKF bearings and nilos seals. I've hit a problem that the hydraulic pipes running up the inside of the steering pipes don't quite reach the hydraulic junctions now, its only about half a mm too short to get the banjo bolt to line up, which is a bit frustrating. There are a couple of things I can think of why the steering tube assembly is now just a little bit longer than when I took it apart.

1)The nylos seals I used as slightly thicker than the original oem ones.
https://www.123bearing.co.uk/seal-32008-XAV-NILOS.php
Picture below.

2) I've put the top bearings in with the cage on the bottom, whereas looking at pictures from other people who have done this it looks like the cage should be at the top, (should have written that down when I took the hearing off!). I can see a bit more of a gap between the top seal and the surround than looks necessary now.

3) I need to tap the bottom bearing cups a little further up into their seats

If anybody could measure the thickness of the bottom seal or tell me what their bottom seal looks like compared to this picture, or confirm if the cage should be on the top of bottom of the bearing race on the top end I'd be obliged. I'll also have a hunt round the other MP3s in the local car park tomorrow and have a look.

I'm sure I'll sort it out with a little reassembly..

Thinking about it, I can't see a reason why the brake and suspension hydraulic lines couldn't be routed along the outside of the suspension tubes which would have made any maintenance far easier

Lot of pinch points and potential for chafing in that area.

Yep, take your point, but probably no worse than a normal motorcycle..

Just thought I would repost this here. In the case shown in this tread the bearing puller would attach under the lip at either end of the cone. As the OP is not in the US getting loaner tools might be more of a problem. Also yes, the bearing installed are creating a standoff effect.

I rotated the top bearing cages so the cage is on top, and that worked fine, closed up the gaps and I could could get the top hydraulic pipes back on.

I've filled the brake and suspension lock hydraulic lines using the syringe method but neither is working yet. Both lock and front brake reservoirs have filled up.

I turned on the ignition and the red suspension warning light has come on (no horn beeping). The suspension lock doesn't do anything, even if you try and press it twice.

I think I did read somewhere the suggestion to get a socket on the nut of the cam which holds the suspension lock cable and move that to get any remaining air out, but it seems as if it doesn't want to move. I didn't try and force it.

Guess will try and bleed everything more tomorrow and see if we can get some joy. Any ideas on the suspension lock appreciated.

OK, more bleeding of brakes, using s syringe vacuum to pull out fluid from the bottom while filling from the top worked well.

Replaced one speed sensor wire which I'd broken by accident when getting one of the legs of which was stuck and the suspension lock is also working fine so can't see any further issues to stop me from completion now.

I've got a few more things I want to do while all the bodywork is off, check the valves, route some more electrical wires etc..

Thanks for all the help..

Final update on this..

Been riding the bike now that its all together again, got the valves adjusted while I had the bodywork off.

Steering is great again, and it passed the UK MOT without any problem.

If anybody in the UK has problems getting their bearing cups out, let me know. Would be happy to lend my bearing cup slide hammer, just so long as it comes back afterwards..

Merry Christmas!