# Rear rim's just cracked.



## Kell (11 Aug 2016)

Heard a rather worrying pinging noise this morning and almost immediately the back wheel felt 'lumpy'. Checked all my spokes and none had snapped, but I could see that the wheel looked buckled. 

I hadn't hit anything so didn't think anything more of it until after I cycled home tonight.

Had a proper look at it as I thought I might have to true it up.

But I then discovered that it's split.

So the questions I have are:

What is the standard warranty on Bromptons and would this be covered?

If not, what is the likely cost of a replacement? Presumably I can just get the rim done rather than a whole new wheel...


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## Kell (11 Aug 2016)

On closer inspection, it's actually split in two separate places. 

Guess I'll have to call the shop in the morning.


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## raleighnut (11 Aug 2016)

That is brake track wear though, not a faulty rim.


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## fossyant (11 Aug 2016)

Worn out rim and by the looks of it you don't clean them often, which makes wear worse.

I used to go through rims in 18 months on my commuter


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## Kell (12 Aug 2016)

It's a commuter. The rims get cleaned when I do the chain. Which is about once every couple of months.

It is just over over a year old and about 2,200 miles.

In contrast, my rather less well built Dahon managed 5 years in the same conditions before the frame snapped. And I kept the wheels as they're still going strong.

While I appreciate that there's less surface area, so it's bound to wear out more quickly than a 26" rim, personally, I don't really think a year is acceptable in terms of 'wear rate'.

Just incredibly pleased I noticed this before setting off this morning as my current route includes a 40+ mph downhill.

I hate to think what could happen if this had been during that.


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## Tanis8472 (12 Aug 2016)

Looks like it's scored all round too


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## Tanis8472 (12 Aug 2016)

Not any way near enough cleaning imo.


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## Rohloff_Brompton_Rider (12 Aug 2016)

Tanis8472 said:


> Not any way near enough cleaning imo.


Too much cleaning IMO.


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## Rohloff_Brompton_Rider (12 Aug 2016)

Kell said:


> On closer inspection, it's actually split in two separate places.
> 
> Guess I'll have to call the shop in the morning.
> View attachment 139030
> View attachment 139029


It's a 


Kell said:


> On closer inspection, it's actually split in two separate places.
> 
> Guess I'll have to call the shop in the morning.
> View attachment 139030
> View attachment 139029


It's a £15 rim or £20 (depending on which you'd prefer) what do you expect?
The design did its job by showing you the rim wear indicator. Seems churlish to complain that something happened because you pushed it beyond its wear limit. 
At the end of the day it's going to cost £20 and an hour or two of you time to swap.


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## Kell (12 Aug 2016)

What rim wear indicator? 

I cleaned the rims about 4 weeks ago when I replaced the chain and rear sprockets. As far as I could tell at the time, they looked brand new. There's not scoring on the wheel rim surface.

I've been on holiday for two weeks so the dirt you see there has accumulated over about two weeks. Do you lot really clean your rims more often than this?

As for what did I expect, well, I expected a new rim to last more than 2,000 miles.

I've been commuting on the same route for 10 years, commuting in London for 20, and been a regular bike rider for about 35.

In all that time, I've never had a rim split on the braking surface; and not even had to replace one under advice that it was worn. I've only ever had to replace them if they got buckled.


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## fossyant (12 Aug 2016)

It's wear. Simple. Those rims are still too dirty. I cleaned mine after every wet ride, which is often in Manchester (almost everyday)


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## Kell (12 Aug 2016)

The bike gets folded up at the end of the day and left in the boot of the car until the next day.

My daily commute involves four separate rides.

You're not seriously suggesting that cleaning the rims four timnes a day is feasible.

In my humble opinion, though I seem to be in the minority, a daily commuter should not need daily attention. 

I'd have said that +/- 2,000 miles is not acceptable for a rim to fail, and I'd have thought the front would get more of a hammering as it does most of the work.

Maybe you all have lower expectations than me. 

Another argument for disc brakes on a Brommie?


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## 12boy (12 Aug 2016)

I have had very good luck with Sun Cr 18 rims having 4 sets in 700c for my other bikes. They do make a 349 rim. Can you lace your own wheels? I don't know if your spokes would be reusable, but I would think that labor, spokes and rim would still be less than a new wheel. I recall seeing your video of that 40 + mph ride and you are very lucky indeed not to have had a rim fail then. For what it is worth, I have been riding for about 40 years and never had a rim split like that either, nor broke a spoke for that matter.


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## Rohloff_Brompton_Rider (12 Aug 2016)

Kell said:


> What rim wear indicator


As per the manual, when the wear indicators APPEARS (I.e., there's no indicator until the rims worn beyond limits) then replace wheel or rim.


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## Rohloff_Brompton_Rider (12 Aug 2016)

Kell said:


> The bike gets folded up at the end of the day and left in the boot of the car until the next day.
> 
> My daily commute involves four separate rides.
> 
> ...


Wrong bike if you expect it to be maintained free. The nearest you'll get to that Utopia is a brakeless fixie.


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## Rohloff_Brompton_Rider (12 Aug 2016)

Tanis8472 said:


> Looks like it's scored all round too


That's the designed built in rim wear indicator. You're not supposed to use the rim once it's appeared, all in the manual.


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## jonny jeez (12 Aug 2016)

Clearly your own fault for braking too often, you must leant to stop with your feet on the ground.

These flimsy little origami bikes are not meant to be ridden, just stored between to your drawing board and site hat.


Right, now I've insulted everyone. Yes it does seem odd to fail so soon but the wear indicator is showing so perhaps you ride a very hilly route, or have to stop a lot more often than usual. Do you ride the brake at all...are the calipers opening correctly.

Whilst I don't think you should HAVE to clean a bike to make it work, a dirty brake cable can seize a caliper on and cause untold wear...especially on you.

I'd swap the cable inners and outers, clean and lube the calipers (do brommies have calipers?) and swap the rim obviously.

Something's not right and I doubt its just due to a build up of dirt on the rims.


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## Kell (12 Aug 2016)

Consider me thoroughly chastised. 

I guess I didn't expect such a dramatic step change in rituals going from AN Other bike to a Brompton. 

I did a lot of research before buying about things to look out for and at no point did I read or hear that they have to treated with kid gloves. 

While I was surprised that my brake blocks lasted little more than 1,600 miles I view them as consumables. I don't (or didn't) put rims in the same category. 

According to my LBS they'll look at it with a view to warranty claims from Brompton or it's 
£30 wheel rebuild
£25 rim
£ possibly (probably) new spokes

Or 

£160 for a full new wheel. 

I'm going to check the front tonight too.


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## rualexander (12 Aug 2016)

£25 for a new standard Brompton rim is a bit steep, should be able to get one for less than £20.
Or you could splash out on an Andra CSS carbide rim and stop worrying about rim wear (special brake blocks required though).
https://www.sjscycles.co.uk/rims-tape/ryde-andra-20-16-x-1-38-349-css-alloy-rim-black-28-hole/


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## Rohloff_Brompton_Rider (12 Aug 2016)

I'm heavy and live on top of a great big hill. Sometimes my rims lasted only a thousand miles. Not a problem now


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## CanucksTraveller (12 Aug 2016)

Kell said:


> Consider me thoroughly chastised.



Yeah, and for what it's worth Kell, I feel for you a bit here. I had no idea that Brompton rims had that short a life expectancy either, if I'd switched from a hybrid (say) to a Brompton I'd have been caught out and probably disappointed too. Every day's a school day I suppose.


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## Kell (12 Aug 2016)

I guess it's just that. Surprise. Four people at work have had Bromptons way longer than me - one's had his 8 years - and not one of them mentioned rim wear. 

I'm also heavier (16 stone) and I ride quicker than any of them though (normal 'cruising' speed in the Brompton is about 17-18mph), so am also likely to be much harder on the brakes. 

That said in those 2,200 miles the bulk of them have been done doing laps of Hyde Park. I can easily do two+ laps without touching the brakes. 

I do have a very steep hill near my home end of the journey, but I only ride that in school holidays when I don't have to put my bike in the car while I drop my daughter off. Other than that, it's very flat. 

Anyway, I took some better pics of the crack, the uncracked bit, plus the front wheel to try and ascertain what I'm looking out for. 

Rear wheel wheel without the crack. What is it here that indicates the wheel is worn?






Front wheel - does this need replacing too? 





Rear wheel crack.


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## Rohloff_Brompton_Rider (12 Aug 2016)

Kell said:


> I guess it's just that. Surprise. Four people at work have had Bromptons way longer than me - one's had his 8 years - and not one of them mentioned rim wear.
> 
> I'm also heavier (16 stone) and I ride quicker than any of them though (normal 'cruising' speed in the Brompton is about 17-18mph), so am also likely to be much harder on the brakes.
> 
> ...


Front wheel not quite there yet but keep an eye on as the rim wear indicator might just be coming through from the photos. 

Re the rear wheel, there are lines but they seem to be a bit 'high'. Strange tbh, the rim wear indicators on post 2013 are far more reliable ime than post 2013.


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## Rohloff_Brompton_Rider (12 Aug 2016)

Kell said:


> I guess it's just that. Surprise. Four people at work have had Bromptons way longer than me - one's had his 8 years - and not one of them mentioned rim wear.
> 
> I'm also heavier (16 stone) and I ride quicker than any of them though (normal 'cruising' speed in the Brompton is about 17-18mph), so am also likely to be much harder on the brakes.
> 
> ...


Based on the newer photos I'd say there should be a good case for warranty replacement.


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## Tim Hall (12 Aug 2016)

(Idle interest) what am I looking for to see the wear indicator in the original photos? I used to run Mavic 719 rims which had wear indicators in the form of a hole drilled part way through the rim from the inside. When it became visible from the outside it was time for a new rim. The indicator was only in one position though. Other rims I've had have a continuous groove in the brake track. When that disappears, again it's new rim time.


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## Rohloff_Brompton_Rider (12 Aug 2016)

Tim Hall said:


> (Idle interest) what am I looking for to see the wear indicator in the original photos? I used to run Mavic 719 rims which had wear indicators in the form of a hole drilled part way through the rim from the inside. When it became visible from the outside it was time for a new rim. The indicator was only in one position though. Other rims I've had have a continuous groove in the brake track. When that disappears, again it's new rim time.


I like the mavic idea, the B's used to be scored in but the scoring caused work hardening, essentially making it the last part of the rim to survive. The new indicator appears like magic when worn. The OP's initial photos show a crack where the indicator is, hence the flaming they got. 
Further photos don't show an indicator which indicates (pun intended) a warranty issue.


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## Kell (16 Aug 2016)

Well it seems like the shop believes it's just wear.

Which it probably is, but as I say, there was no 'indication' of any real wear before it went. 

I guess forewarned is forearmed and all that.


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## berylthebrompton (17 Aug 2016)

Kell said:


> Well it seems like the shop believes it's just wear.
> 
> Which it probably is, but as I say, there was no 'indication' of any real wear before it went.
> 
> I guess forewarned is forearmed and all that.



So you have to pay? I must say the Brompton warranty seems to be a bit like Teflon. I had to pay to have my chain and sprockets changed after 500 miles/5 months!


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## srw (18 Aug 2016)

berylthebrompton said:


> So you have to pay? I must say the Brompton warranty seems to be a bit like Teflon. I had to pay to have my chain and sprockets changed after 500 miles/5 months!


The Brompton warranty covers the frame, not consumables. Way back in the dark ages I had frame welds go on my first Brompton - replaced under warranty without question.

Chain, sprockets and rims are all consumables, and I wouldn't expect any warranty to cover them beyond the first few weeks. That said, if I were the OP I'd be popping into Brompton Junction in London rather than some random bike shop. To put things into context, I have in my time been rather heavier than him, and used to ride 5 miles each way every day; I now do the same ride 2 or 3 times a week and have also done longer rides. In the last 20 years I've mangled precisely one rim. On the other hand my first Brompton got to the stage where one of the steel struts rusted right through.

Having said that, the photos don't look like a bike which was utterly brand new only a year ago. In particular, that muck on the inside of the rims and on the spokes looks more like pitting than standard commuter dirt build-up.


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## Kell (18 Aug 2016)

In fairness, it's hardly some 'random' shop. It's an official Brompton dealer and it's where I got my bike from.

What I might do is ask them for the old rim once the new one is finished and then have a conversation with Brompton.

As for the bike, what can I tell you? It's done 2,200 miles since I got it last August and it was brand new on the Bike to work scheme. I ride it at least 12 miles a day, five days a week in all weathers. It doesn't spend any time outside other than when I ride it as we have a secure car park at work and it's either garaged or in my car at night.

I tend to just clean the braking surface rather than the whole bike. And certainly don't worry about dirty spokes.

As for the cost, it would still be cheaper for me to buy two new Bromptons every year than it would to commute, so I'm happy to pay for maintenace - I'm just surprised that a rim would only last this long given my previous bikes were treated exactly the same and I've never broken a rim. On any bike.


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## Hugh Manatee (18 Aug 2016)

The only time I have ever had anything to do with Brompton stuff is when I needed a rim to build a rear wheel for a Moulton I had saved. I wasn't impressed.

The first rim I got didn't have any holes in it. Well, it had the valve hole drilled but nothing for the spokes!

The replacement did have the correct number of holes but the join in the rim was very obvious and the whole thing appeared to be made from some sort of cheese.

I did manage to build my first wheel; easy as it was a Sturmey hub. The bike is now with my mum and potters in and back along the Totnes cycle path regularly.

Having read this thread, I'm going to check it next time I'm down there.


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## srw (18 Aug 2016)

Kell said:


> In fairness, it's hardly some 'random' shop. It's an official Brompton dealer and it's where I got my bike from.


Not all Brompton dealers are created equal...

And a "brand-new" bike, if it's a stock build, might have been kicking around in the shop for a while, and might not be a current spec - though if it's been stored reasonably properly I can't imagine how the rims and spokes could have got into that condition.


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## Kell (18 Aug 2016)

Wasn't a stock build. Built to my spec. Never seen another like it.

H6L in Lime Green.

this was it on day one after I'd swapped the bars, but before I'd trimmed the cables.







I don't really know what to tell you about the condition of the wheels. It seems like you're doubting the fact that it's been used to commute on. Do you ride in London at all? Every bike I've owned and ridden in London picks up this horrible road grime which turns into a disgusting sludgy mess when mixed with oil. 

The rear sprockets were caked with it when I replaced them and the chain, and the jockey wheels needed it scraping off so they'd roll freely.

It's certainly worse with the Brompton than my previous Dahon because everything is som much closer to the ground, but I don't believe it's unique to me.


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## 12boy (18 Aug 2016)

Kell, I am sure you are right about the gritty filth you pick up on those streets. Sounds like grinding compound to me and it is no wonder your rims are abraded so quickly. I remember your terrifying video about going down the street at 40 mph and the braking needed to slow from that must be intense. If that grit is being imbedded in your pads as well it must contribute to the wear. Shame you cannot fit disk or drum brakes.


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## rualexander (18 Aug 2016)

2,200 miles seems a reasonable distance on small wheel rims, I've had Sun CR18 26" rims last about the same distance before the rim blew off (no wear indicator).
But equally I've had about 8,000 miles from other brands of 26" rim.
The rim isn't cracked, it's just the wear indicator groove appearing.
Your front rim looks like the wear indicator is starting to show through as well, so probably best to get it replaced at same time.


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## Kell (18 Aug 2016)

The rim may not look cracked. But there is about a mm in height difference between the top part and bottom. Plus, I actually heard it 'ping' when it went.

It's hard to see in the pics, granted. In fact when i took the wheel off and showed it to my missus, she couldn't see it until she put her finger on it*. It's also split in two separate places and covers around 1/3 to 1/2 of the wheel.

More research online has suggested that the too much PSI could be a culprit - especially on worn rims. The tyres were pumped up to their maximum PSI, but not over-inflated.

In conclusion, the guy in the bike shop said that the wear indicator may not have appeared, but the rims are concave, therefore they've shed material and are weaker. 



*Yes, I'm aware this sounds rude. But I couldn't be bothered to edit it.


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## Pale Rider (18 Aug 2016)

Kell said:


> More research online has suggested that the too much PSI could be a culprit - especially on worn rims. The tyres were pumped up to their maximum PSI, but not over-inflated.



The pressure exerted by inflating the tube should not be under-estimated.

I was on a long ride with a group when one of the others had a tyre blow off a rim.

It was a mountain bike running shallow tread tyres.

After refitting the tyre we put several cable ties around the blow-off spot it in a bid to keep the tyre on the rim for the few miles we had left.

While inflating the tube - with a hand pump - each of the cable ties pinged off.


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## Kell (18 Aug 2016)

Without going back through the thread and giving out individual thanks, can I just say a thank you to everyone that's contributed?

My frustration has not been with your comments, but with what is, in my opinion, a pretty short lifespan for something which is designed for daily use. 

I hold up my hands and say I didn't RTFM - who does? - so didn't know about the rim wear indicator. 

I think it's a combination of my ignorance, plus the fact that my chain and sprockets wore out about a month earlier, and diagnosing a horrible creaking to the rear swing arm and then finding out that Brompton see the rear-swing arm hinge as a wear and tear item too has meant that all in all, the last two-months have been a bit of a rude awakening.

I don't see any bike as a maintenance-free option, but I did expect a (relatively) expensive and well-respected commuter to last a little longer. 

I've always been more of a 'fix it when it goes wrong' type of person though, rather than a 'spot it early and try and prevent it' type of person.

I guess I'm going to have to be a bit more pro-active.


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## 12boy (19 Aug 2016)

As far as that rear hinge goes, I very carefully bored a small hole in the frame , and used a magnet to remove metal shavings as I went. I then dribbled in a little oil and then sealed the hole with some wax I use for chains which becomes fairly malleable when warmed between fingers. I got this idea from reading a post which advocated installing a Zerk fitting to allow heavy grease to be inserted under pressure, but I would hold off on that until it becomes necessary to have the hinge bushing replaced. Still, the hinge is silent and I can't see how keeping well lubed could hurt in any way. Other having to replace the rear cog fairly frequently and suspension elastomer once I find the Brompton to be pretty durable.


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## Fab Foodie (19 Aug 2016)

What are peeps thoughts on softer pads than the standard issue such as Koolstop Salmons to reduce rim wear?


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## Kell (19 Aug 2016)

I'm currently on Swissstop Greens after the original ones lasted about 1,000 miles.


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## berylthebrompton (21 Aug 2016)

srw said:


> Chain, sprockets and rims are all consumables, and I wouldn't expect any warranty to cover them beyond the first few weeks.



Consumable parts still need to made correctly. Just by labelling them "consumable" doesn't mean they can be poorly made. I work for a consumer electronics manufacturer - batteries are consumable. Doesn't mean they don't fail before their designed finite life. As a responsible manufacturer we can test and tell whether the end of life is normal or premature. Brompton, or the place of purchase, should be able to prove the wear is normal.

Kell - If it was less than 6 months old, I would have said to make a consumer law claim against the place of purchase. Unfortunately As your Brompton is older than that, the onus is on you to prove it wasn't fit. Based on the replies from everyone, doesn't sound like that would be easy. Better chalk this one up to experience.


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## Kell (22 Aug 2016)

It did make me spit out my tea while watching the Greg Wallace programme about Bromptons when the MD of Brompton mentioned that the wheels are built particularly strong to withstand abuse.


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## Kell (17 Apr 2019)

I was just looking for this thread to point someone else to, but thought I'd update that the replacement wheel was going strong up until a month or so ago, when I replaced the lot as the hub sounded awful. Grinding and general unpleasant.

Still not got around to fixing the old one, but have bought the parts. As I lost some of the bearings when I took it apart to see how it worked. D'oh.

What I would say is that I still think the original wore out too soon. After this thread, I started cycling that hill every day and the replacement wheel lasted a further 5,000 miles and didn't show any signs of wearing through...


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## byegad (17 Apr 2019)

ALL rim braked small wheels have a shorter life than 'full sized' rims.
Bromptons used to be known for lacklustre braking. Fitting a more aggressive block sorted that, but at the expense of wear on the rim. My badly treated commuter on 700C rims managed about 4500 miles before the wear indicator showed a new rim was needed. As 10 out of my 16 mile each way commute was on little used country roads, and 3 was on A roads, the real wear took place on wet days in town.


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## Ming the Merciless (17 Apr 2019)

Putting a wet dirty Brompton in the boot of a car will not have helped matters.


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## Kell (17 Apr 2019)

byegad said:


> ALL rim braked small wheels have a shorter life than 'full sized' rims.
> Bromptons used to be known for lacklustre braking. Fitting a more aggressive block sorted that, but at the expense of wear on the rim. My badly treated commuter on 700C rims managed about 4500 miles before the wear indicator showed a new rim was needed. As 10 out of my 16 mile each way commute was on little used country roads, and 3 was on A roads, the real wear took place on wet days in town.



As I say, I'm going to chalk it down to experience. I'm a little better with cleaning since this happened, but I'm still convinced that cycling around Hyde Park probably contributes to the excessive wear as there are sand horse tracks all around it. Pretty sure that the fine dust blows over onto the cycle lanes and gets flicked up, mixed with the oil and turned into a grinding paste.

It's very hard to prove what constitutes excessive wear, but I'd say that all things being equal, the new rim should have worn through much more quickly. As I was doing an additional 6 miles daily and a lot more severe braking. Yet it lasted more than twice as many miles/years and while showing signs of wear, was certainly not down to any wear indicator.


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## Fields Electric (8 May 2022)

Just for the record. Mine is on 4 years and 6500 miles and the rear rim is ‘going soft’ on the drive side. That means I can dint it with a flat screw driver. The drive side is worst because it catches the oil from the chain. This collects dirt, which turns into a grinding paste. I clean the rims when they look grey. I also use brake pads that are designed from aluminium rims. The blocks do last about 1800 miles and not cheap.


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## u_i (8 May 2022)

Fields Electric said:


> Just for the record. Mine is on 4 years and 6500 miles and the rear rim is ‘going soft’ on the drive side. That means I can dint it with a flat screw driver. The drive side is worst because it catches the oil from the chain. This collects dirt, which turns into a grinding paste. I clean the rims when they look grey. I also use brake pads that are designed from aluminium rims. The blocks do last about 1800 miles and not cheap.



You normally measure the rim thickness with an inexpensive dental caliper, looking for the places where you get the lowest readings. You should absolutely never go below 0.5mm and many people recommend not even going below 1.0mm. I usually push down to 0.7mm.


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## rogerzilla (9 May 2022)

I wore out a front 26" rim (the rim that isn't constantly sprayed with gritty water) in 18 months of commuting, half of it on country lanes. It was a fixie, as a rear rim with a brake would have worn out many times faster.

A rear 16" rim will not last long on mucky roads. That type of wear indicator groove does tend to encourage splits, unfortunately.


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## Illaveago (9 May 2022)

Ah! Finally an answer to the question in my head ! So the groove running round the rim is the wear indicator ? . Handy of them to put in a weak spot from a split to follow ! 
So if you go beyond the limit of the wear indicator the rim should look perfectly alright!


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## u_i (9 May 2022)

Illaveago said:


> Ah! Finally an answer to the question in my head ! So the groove running round the rim is the wear indicator ? . Handy of them to put in a weak spot from a split to follow !
> So if you go beyond the limit of the wear indicator the rim should look perfectly alright!



The rim wear indicators are usually quite conservative and wear is usually not uniform. This is why it can be good to measure after long-term use of the rim. Some rim manufacturers use the reverse: a hole begins to show once the wear gets to be excessive.


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## keithmac (9 May 2022)

My GTECH with 700c did over 6,000 miles of commuting with virtually no cleaning most of the time before the wear groove (sp?) showed it was time for another rim, Clarkes brake shoes.


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## Kell (10 May 2022)

Well, seeing as this thread has made a resurgence, I may as well update.

Still on the replacement wheel, and up until the pandemic, was still doing just under 2,000 miles a year. And in much harsher conditions than when the original wheel cracked - my daily commute includes a 40MPH downhill section (which I'd only just started doing at the time of the split), so I'd have thought if that wear was 'normal' then I'd be replacing it every 6 months.

As it is, my Strava log indicates that I've now done around 10,000 miles on the Brompton and the rear wheel looks OK.

As I maintained all along (and still do) that original wheel wore out much quicker than it should have done.


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## Kell (3 Oct 2022)

Kell said:


> I was just looking for this thread to point someone else to, but thought I'd update that the replacement wheel was going strong up until a month or so ago, when I replaced the lot as the hub sounded awful. Grinding and general unpleasant.
> 
> Still not got around to fixing the old one, but have bought the parts. As I lost some of the bearings when I took it apart to see how it worked. D'oh.
> 
> What I would say is that I still think the original wore out too soon. After this thread, I started cycling that hill every day and the replacement wheel lasted a further 5,000 miles and didn't show any signs of wearing through...



If that post was true, then the fact that my current wheel has just gone crack means it lasted around *5,000 *miles too.

Currently in the shop for a rebuild.

This time will be slightly easier to track as I've now downloaded that 'mainTrack' app that someone recommended on here.

ETA - because I know the rough dates, the app can calculate the distance retrospectively.

I overestimated it somewhat - it was actually *3,400...*


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## presta (3 Oct 2022)

Fab Foodie said:


> What are peeps thoughts on softer pads than the standard issue such as Koolstop Salmons to reduce rim wear?





Kell said:


> As it is, my Strava log indicates that I've now done around 10,000 miles on the Brompton and the rear wheel looks OK.


I've had about 20,000 miles out my Mavic A719s, with fairy abrasive Shimano M55/T blocks. That would be equivalent to about 12,000 miles on a Brompton with smaller wheels.


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## Fab Foodie (3 Oct 2022)

presta said:


> I've had about 20,000 miles out my Mavic A719s, with fairy abrasive Shimano M55/T blocks. That would be equivalent to about 12,000 miles on a Brompton with smaller wheels.



Blimey - post from the past!!
I have Kool Stops (Salmon Front/Black rear) on all my bikes now, Broms and 700c wheels, wouldn't change now on stopping performance...no idea about rim wear though!


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## ExBrit (3 Oct 2022)

I have to agree with the OP. I would not expect the rim to fail, even if filthy and gritty, in such a short time. But it's not the time, it's the miles and it does sound as if the OP puts more miles on than I do. Cleaning the bike and lubing the chain once a week will increase the MTBF. It's 15 minutes well spent. If you ride a lot and in bad conditions it's 15 minutes even better spent.


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## berlinonaut (3 Oct 2022)

ExBrit said:


> But it's not the time, it's the miles and it does sound as if the OP puts more miles on than I do.


It's miles, riding style, cleanliness of the bike, weather, type of breakpads, weight of the rider, speed, surface you are riding on, anxiety of the rider  (how often does he break?) and probably a couple things more. One of those is obviously the type of rim itself. Also, it is quite typical that the rear rim cracks earlier often, for one as it is typically grittier than the front and second a lot of riders use the rear brake intensively on the Brommi. So a lot of things that influence the lifespan and a lof of influence of the rider.


ExBrit said:


> Cleaning the bike and lubing the chain once a week will increase the MTBF. It's 15 minutes well spent. If you ride a lot and in bad conditions it's 15 minutes even better spent.



I do have my doubts that lubing the chain increases the lifespan of the rims but who knows.  At 3.400 miles @Kell is at the lower (but not the lowest) part of the distribution in terms of rim lifespan. The majority seems to be between 10.000km and 25.000km, with a peak at around 20k km. However, sportier riders with a harsh riding style are typically way lower than that.
If I was @Kell I'd probably give the Sun CR18 a try - it is a dog to put tires on but rumors say it would be way more longlasting than other Brompton rims.
silver
black


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## ExBrit (3 Oct 2022)

berlinonaut said:


> It's miles, riding style, cleanliness of the bike, weather, type of breakpads, weight of the rider, speed, surface you are riding on, anxiety of the rider  (how often does he break?) and probably a couple things more. One of those is obviously the type of rim itself. Also, it is quite typical that the rear rim cracks earlier often, for one as it is typically grittier than the front and second a lot of riders use the rear brake intensively on the Brommi. So a lot of things that influence the lifespan and a lof of influence of the rider.
> 
> 
> I do have my doubts that lubing the chain increases the lifespan of the rims but who knows.  At 3.400 miles @Kell is at the lower (but not the lowest) part of the distribution in terms of rim lifespan.
> ...



Obviously I was referring to MTBF generally. I think getting into the mindset of cleaning your bike regularly and proportional to usage is a good thing. I've been riding as an adult for 30 years and only figured this out maybe ten years ago.

So am I right in understanding that newer Brompton rims have a black line that appears as a wear indicator?


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## berlinonaut (3 Oct 2022)

ExBrit said:


> So am I right in understanding that newer Brompton rims have a black line that appears as a wear indicator?



I've not yet managed to break through one of Brompton's double wall rims. Some say the'd have an internal wear indicator - when you see it it's time to change the rims. With the older single wall rims it depends from the age: Some had an external ring (once it's gone time for a change), others had nothing. Brompton used several different rims over the years with the single wall. Thus these older experiences are neither consistent nor can they used 1:1 on the double wall rims they use since 2013.


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## Kell (20 Oct 2022)

berlinonaut said:


> Some say the'd have an internal wear indicator - when you see it it's time to change the rims.



I didn't take a picture of mine this time around, but there was no other indication that it was about to go. The wear indicator was not visible anywhere, there was just the split.


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