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MG parts spares and accessories are available for MG T Series (TA, MG TB, MG TC, MG TD, MG TF), Magnette, MGA, Twin cam, MGB, MGBGT, MGC, MGC GT, MG Midget, Sprite and other MG models from British car spares company LBCarCo.

MG Midget and Sprite Technical - Moss roller front wheel bearings

Today I replaced the front wheel bearings with taper roller bearings: Moss Part Number GHK1142X (X= taper)
I had to thin the spacer ring a bit, but that was all. Cost €40 per side. The radius of the inner bearing was also large enough. I hope they last a long time.


Flip Brhl

Aren't roller bearings also quieter than standard ball bearings?
GuyW

About time we had another fwb thread. 🤣🤣.

I never noticed rollers in good condition being noisey Guy. Have you then?

35 quid per side for tapers? They've gone up haven't they?

You might find some nos original angular rollers for that. 😅😅. Or maybe not. Probably as rare as hen's teeth these days. 😆.


anamnesis

T'was a question, Anamn. Though not well worded. Amongst many light/kgs of discussions on fwbs I recall a claim that the tapers were quieter than originals. Maybe just that they can be adjusted more precisely. But the question was asking for confirmation from real experience.
GuyW

Can you hear them anyway above the engine noise, back axle whine, other rattles etc? 🤣
Bill B

Taper roller bearings are quiet providing they are set up properly. I have had on line argumements regarding this. I argue that you can't adjust them by simply tightening the nut. The spacer needs to be either lapped or shimmed so the two inner races are locked together hard with slight play against the outer races.

Have a good Hogmanay

Jan T
J Targosz

MGB bearings are tapered rollers with shims.
Dave O'Neill 2

Many vehicle applications exist with taper rollers hubs on stub axles with no spacer to clamp the inner races, VW, Porsche, Ford are a few that spring to mind. Care needs to be taken to adjust them properly but they seem to work fine. I have seen the result of one that was over tightened and the hub/wheel fell off after the bearings welded themselves together and to the stub axle and that sheared.
David Billington

But, the spacer IS required on Spridget stub axles, in order to torque the spacer and inner races, which adds strength/rigidity to the axle.


anamnesis

I still have a few sets of the original RHP bearings knocking around in the basement.I suspect the mileage the cars do now a set would last many years.
Bob Beaumont

When I rebuilt the Frog, I bought some used disc hubs (and calipers), with RHP bearings, which I rebuilt with new discs but retained the bearings. No significant play yet and it passed the equivalent of an MOT (new kingpins of course).
Bill B

"I suspect the mileage the cars do now a set would last many years. "

For many years, read 'forever'. They were good for 100k miles anyway.

anamnesis

Yep. they should last forever if maintained properly---cleaned,regreased and new seals every 30-40,000 Contamination is the killer, good sealing is a must.
David raised a good point about moderns running tapered races without spacer blocks and yes it's quite common, BUT our older cars' stub axles don't like it much, maybe for normal road work it's ok I ran a V8MGB without for ages without an issue. But for hard driving ,competition, the spacer(properly shimmed) is very necessary. We ran an E type in Targa events for a few years and soon found out that without the spacers the stub axles flexed enough to push the brake pads back causing a very long unreliable brake pedal--refitted the spacers and tweeked the nuts up and bingo, good brakes again.

willy
William Revit

Ah nice to have a FWB thread! Let’s see if we can get this to over 400 posts…

Anam - NOS FWBs do still occasionally come up for sale on eBay - I wonder if people have forgotten or do no know about possible issues with alternatives. The Meditech modified (machined with correct radius) new bearings were not available for very long.

Cheers
Mike
M Wood

Yep, big advantage of shim and torque is it increases the effective working diameter of the stub axle by the distance the inner of the bearing adds on the side under compression. Given how easily Spridget stubs bend or crack if you hit something that is very useful.
Jag IRS shims, C16626, are perfect size and available in 3 and 7 thou thicknesses.

Interesting find on the E type Willy.
We've seen several Bs with shims/spacer omitted weld themselves up as described above.
Paul Walbran

Happy New Year people-
Paul-The E type was interesting, to say the least (read frustrating) we'd been chasing this disappearing brake issue for a while.E's are a bit prone to cooking up the rear brakes and we'd redone the hydraulicks with a different (modern twin circuit) m/cyl with rear brake pressure tapered limiting and it was all working really good except in all the really tight bendy stuff then the pedal would randomly drop-- As you're probably aware the stub axle is also separate to the upright and fits in a taper with a nut on the backside of the upright ,we first picked up on there being an issue in that area when during routine checkovers the nuts always pulled up a bit nomatter how tight they got screwed up. Initial thought was it was stretching the axle but after having new axles made from good material and measuring and cracktesting the axle a couple of times the axles were fine but---. After refitting the spacers and tweeking the nuts on both ends up rock hard all was well again,-- well not again really,-- at last. A bit of the price you pay with modern sticky tyres on larger wheels on older cars i guess.
Cheers for the New Year
willy
William Revit

How much play do those bearings need? At the moment they have zero play but they turn easy even without the wheel on the hub, a little bit slower with grease. I do have shims in stock.
Flip Brhl

The instructions https://www.moss-europe.co.uk/en-gb/product/attachment/GHK1142X/GHK1142X_instructions.pdf say 0.002" to 0.004".
David Billington

Yeah, I'd head for 'just' some minimal clearance.
Some/most modern cars run slight preload but are mostly larger bearings.
If you can get somewhere around .001"-.002" ish you'll be fine. When the hubs and bearings get up to operating temp you'll find you will probably have zero clearance/endfloat, but if you have that tiddly little bit to start you'll know they're not getting too tight hot.
willy
William Revit

As aging stub axles has been mentioned - anyone tried these replacement items from Colin Dodds of Sprite Parts in Dural, NSW? https://www.spriteparts.com.au/shop/superstubs.html

Cheers
Mike
M Wood

At $780 for a pair of modified originals, I doubt many.

It would be interesting to know, exactly, what are the failure rates of our stubaxles anyway; both in racing and normal road use. 1 a year? 10? None? How many?

I'm sure there must be failures, but are we REALLY driving around with accidents waiting to happen? I doubt it.

But luckily for me, I have two complete spare sets, that haven't been on the road since I got them circa 20 years ago, and hadn't been on the road for at least 10 yeaes before that. Not likely cracked.

But if I wanted to spend that kind of money on the front setup, I rather address the entire front suspension/axle setup anyway, and get rid of the threaded fulcrum and kingpin arrangement entirely.

Not so long ago, Guy I think it was, posted a reference to a new design by somebody, possibly on facebook.

Anything come/coming of that I wonder?

anamnesis

You just never know------My friend Nick bought a low mileage one owner Triumph TR6, it had been babied all it's life and never been in any sort of accident. Luckily he was just driving along with his wife in town about to go out on the main road doing around 70K/h and a stubaxle snapped off and the wheel went under the car and flipped it over on it's lid, broke the wife's neck (She's fully---90% recovered) but just brings home to you how easy things can happen. I've never seen a Sprite/midget?MGB stub axle break, but i wouldn't be surprised if a racer somewhere has at least cracked one.
William Revit

Willey,
Sprinzel, in one of his books, says that front axle breakages on early Sprites were quite common. Tracked down to a casting fault I think. He was a DNF on one major european event when leading (his class?). Cant remember which, I would need to check in his book, or someone else here will tell me.
GuyW

I was a passenger in a Mini that shed a wheel when the threaded end of the shaft fractured.
The car was passing a minibus at a fair speed at the time.
The wheel flew up, bounced off the side of the minibus and tried to join me in the passenger seat.
Glass everywhere (and a nasty smell).
Lucky that the bus was there as the car leaned on it instead of somersaulting off the road.

Not my car, but I never liked the wretched things anyway.
Greybeard

“Sprinzel, in one of his books, says that front axle breakages on early Sprites were quite common”

Presumably that would be with the A35 stub-axle. I’m not sure the spindle had the same large radius as the disc brake version.
Dave O'Neill 2

Some early 10" wheeled minis used a thinner steel, which was prone to tearing out around the wheel studs, leaving ragged washers attached to the hub and no front wheel. Friend and I going to his wedding using wedding cars tunbridge wells in Dorchester,1971, both dressed in full formal wedding 'top hat & tails' as I was his best man. One front wheel made a bid for freedom and the car screeched to a stop. Sparks. A gang of lads from adjacent building site came over and fitted the spare, lifting the car by hand as there was no jack and lots of them. Mike and I handed out cigars and we were on our way and still got there before the bride.
GuyW

In his wonderful book "Spritely Years" in 1958, John Sprinzel complained about the front axles breaking on both the Sprite and the A35. They share the same front axle. Ten years later, in 1968, he lost the London-Sydney Marathon due to axle failure. A Porsche 911 won that race, even though he had been hours ahead until the break. He himself, 26 years later, was remarkably cool about it: "It would have been a glorious finale for PMO 200 and a crowning achievement for a career in motorsport that had begun so many years before."
Flip Brhl

Great stories from Guy and Flip!
My best shaft fracture tale was from a Severn class LifeBoat where the PTO shaft runs through a pillow block bearing roughly the size of a small shoe box.
I did a delivery passage on the boat from Helensburgh to Poole.
On the way the bearing failed and got so hot that it melted the shaft which duly parted.
Turned out that the boat's fulltime mechanic had never done the planned maintenance greasing since the boat was new.
The shaft is about 2 inches diameter, for context.
The engine room has fire and smoke alarms fitted. Nothing happened; the only indication was the horrific unholy racket of the remains of the shaft thrashing around and ripping chunks out of everything it hit.
He'd also never done the weekly alarm tests.
I don't know where he works now.
1500 horsepower with nowhere to go will do that. Sure woke me up anyway 😯
Greybeard

We have cracked a stub axle on the K Midget, albeit with the help of a bank in a hillclimb.

London-Sydney 1968 was won by Andrew Cowan in a Hillman Hunter, with Paddy Hopkirk 2nd in a BMC1800, and a Ford Falcon 3rd. Porsche had to settle for 4th. Cowan reportedly asked Chrysler for a slow car, reckoning the name of the game was to be among what he expected to be only a few finishers. He was right.
I remember at the time we were all a bit gobsmacked about the Hunter, considering the status of BMC works teams at the time and the number of 1800s they entered.
They didn't even get the team prize, which went to a trio of Falcons.
Paul Walbran

Slow is a relative term. Compared with other top line rally cars, the Hunter probably was slow.

However I can vouch that it was still, but my reckoning, a bl***y fast car when it blatted past me on my bicycle by the Royal Showground - what's now known as Stoneleigh Park! National speed limit was 70 then and it was well over that!

C
C Mee

This thread was discussed between 28/12/2025 and 23/01/2026

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