# Tannus tyres on a Brompton



## simon.r (12 Aug 2017)

I've fitted Tannus tyres to my Brompton. 

Fitting them is probably worth a thread of its own, but suffice to say it's doable at home but very difficult - and I consider myself a fairly competent home mechanic. 

I've done 10 miles on them and my initial impressions are that they're absolutely horrible and very close to being dangerous. 

There are 3 issues:


The drag. It's not quite as bad as riding through sand, but it's very noticeable. I need to be in at least a gear lower (on a 6 speed) if I want to put the same effort in. Obviously this means a slower speed, which I could live with, but the feel of the tyre is horrible. 
Cornering. Taking a corner at anything over 10mph is a nightmare. The tyres feel as if they're trying to squirm off the rim. I'm an experienced cyclist and managed to control the bike, but I really think someone with little experience or poor bike handling skills would have been off. 
They track horribly along any road defects - the edges of filled in trenches, manhole covers etc. 

On the positive side they were OK on a straight hard-packed gravel track and I didn't get any punctures

I've read reviews that say they get better after a few miles, so I'll give them a hundred miles or so and report back. 

(TLDR - they're a nightmare to fit and ride horribly, but may improve over time - I'll update in due course).


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## MacB (12 Aug 2017)

Brave man will be interested to read your follow up


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## Racing roadkill (12 Aug 2017)

simon.r said:


> I've fitted Tannus tyres to my Brompton.
> 
> Fitting them is probably worth a thread of its own, but suffice to say it's doable at home but very difficult - and I consider myself a fairly competent home mechanic.
> 
> ...


They take some getting used to, but if you can ride a bike properly, they are fine. I've got over 1000 miles on mine, and that's on a road bike, they can be 'skittish' on poor surfaces, but if you make allowances, the disadvantages are massively outweighed by the advantages.


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## CopperBrompton (12 Aug 2017)

They are truly horrible things. Cornering on them in the dry feels like you're about to fall over at any moment. Gawd knows what they're like in the wet. Just fit Marathon Plus – I average one visit from the puncture fairy every 2000 miles.


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## simon.r (12 Aug 2017)

Racing roadkill said:


> They take some getting used to, but if you can ride a bike properly, they are fine. I've got over 1000 miles on mine, and that's on a road bike, they can be 'skittish' on poor surfaces, but if you make allowances, the disadvantages are massively outweighed by the advantages.
> 
> View attachment 367674



Did you find they got better after a few miles?


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## TheDoctor (12 Aug 2017)

They sound awful.
I fitted Marathons to my Brommie in November 2011, and (fingers crossed) I've not had a visitation since.


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## Yellow Saddle (12 Aug 2017)

simon.r said:


> I've fitted Tannus tyres to my Brompton.
> 
> Fitting them is probably worth a thread of its own, but suffice to say it's doable at home but very difficult - and I consider myself a fairly competent home mechanic.
> 
> ...



I'm happy for you that those tyres at least delivered on their primary promise.
However, the side-effects were to be expected, especially the drag. Tyre drag (also called rolling resistance) is a very well-understood science and therefore, on paper, there is no way that a solid tyre with high hysteresis will have a low RR. Some converts say they cant feel the difference but either they are post-rationalising their expensive purchase or they are mechanically naive. It is easy to display the incredibly high RR. Take two comparable wheels, say two front wheels, one shod with a pneumatic tyre and the other with that silly putty tyre of yours. Bounce them on a hard surface in front of you. Throw the wheel as if you're throwing a plate at a Greek wedding, but turned vertically. Put a little spin on it so it bounces back to you. Notice the difference in return energy between the two. That return energy is a visual report of what's happening when you ride.
They will not get better over time, you will just get (slilghtly) used to it. There is no plausible explanation of how they can get better.
There is a reason why the pneumatic tyre was invented.


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## simon.r (12 Aug 2017)

Yellow Saddle said:


> I'm happy for you that those tyres at least delivered on their primary promise.
> However, the side-effects were to be expected, especially the drag. Tyre drag (also called rolling resistance) is a very well-understood science and therefore, on paper, there is no way that a solid tyre with high hysteresis will have a low RR. Some converts say they cant feel the difference but either they are post-rationalising their expensive purchase or they are mechanically naive. It is easy to display the incredibly high RR. Take two comparable wheels, say two front wheels, one shod with a pneumatic tyre and the other with that silly putty tyre of yours. Bounce them on a hard surface in front of you. Throw the wheel as if you're throwing a plate at a Greek wedding, but turned vertically. Put a little spin on it so it bounces back to you. Notice the difference in return energy between the two. That return energy is a visual report of what's happening when you ride.
> They will not get better over time, you will just get (slilghtly) used to it. There is no plausible explanation of how they can get better.
> There is a reason why the pneumatic tyre was invented.



You're right of course, but I wanted to try them for myself. I think it was you who used the phrase "the cost of learning" (or something similar) in a previous post about messing up when doing home mechanics. I bought these tyres prepared to treat it in that manner.


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## Yellow Saddle (12 Aug 2017)

simon.r said:


> You're right of course, but I wanted to try them for myself. I think it was you who used the phrase "the cost of learning" (or something similar) in a previous post about messing up when doing home mechanics. I bought these tyres prepared to treat it in that manner.


Please don't see my post as a criticism for buying them. I'm just appreciative of someone who is honest after throwing down good money. So often this type of thing is given a type of spin that Alistair Campbell would be jealous of. I've purchased plenty of dud products in my life. School fees, all of it.


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## simon.r (12 Aug 2017)

Yellow Saddle said:


> Please don't see my post as a criticism for buying them. I'm just appreciative of someone who is honest after throwing down good money. So often this type of thing is given a type of spin that Alistair Campbell would be jealous of. I've purchased plenty of dud products in my life. School fees, all of it.



I didn't read your post as a personal criticism.

I'll give them a few miles (though I note your comments about getting used to them*) and then, I suspect, try to remove them. If I can get them off without destroying them I'll eBay them with an honest account and see what they go for!

*At the moment I''m in the fortunate position of having two Bromptons, one with pneumatic tyres, one with Tannus tyres, so I'll be able to compare them after I've got used to them.


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## User10571 (13 Aug 2017)

I'm struggling to think why one might make the already questionable handling of a bike, even more so - but I guess that comes down to how you use the bike. Mine is not my everyday ride, mostly weekends only, and not significant mileage.
My 2013 S-type came with Marathons, and until I swapped them (there's plenty of life left in them) for Kojaks earlier this year they hadn't suffered any punctures.
The Kojaks have noticeably less rolling resistance - you roll further for each push of the pedals - which is nice. So far, I've not suffered a puncture with the Kojaks. If I want to improve the handling of the bike further, 10kg of goods from Sainsburys shelves, placed in the C-bag will do that - which, I think, speaks volumes about the design of the bike.
I don't carry a pump or tools on my Brommie. Aside from the fact that the Ti rear triangle lacks the pegs for a pump, I bought the bike on the basis that if it goes wrong, I'll fold it up and put it and me in a taxi or on a bus / train. Or walk / push.
I confess it took me a while for me to get my head around the fact that the Brompton wasn't going to deliver the sort of handling that any of my four 700c - wheeled bikes do.
Since I had my lightbulb moment, I've grown to love the Brommie. I've thrown enough Ti currency at the bike (in an effort to make it lighter) that it would've been cheaper for me to buy a yacht and keep it moored in Marbella - but if there was one improvement tip I was to offer to a Brommie rider - it would be to invest in Kojaks. The effect is immediate and obvious.
But, as I said earlier, it depends very much on how you use the bike.
Like others on here, @simon.r I remain interested to hear how your your opinions of your relationship with your Tannus tyres develop.


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## simon.r (13 Aug 2017)

A few more miles this morning and I just couldn't take any more:






I don't have the Tannus removal tool and after a few minutes of trying to use a pair of grips as a substitute decided that I've wasted enough of my time on these tyres and resorted to a hacksaw and Stanley knife. 

Farewell Tannus tyres, you will not be missed.


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## User10571 (13 Aug 2017)

@simon.r That made oi larf biggly!
Thank you for undertaking the research on everyone's behalf.
Occasionally, I've done the same myself 
ETA: Schwalbe Kojaks are your friends.


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## simon.r (13 Aug 2017)

User said:


> I reckon that every other Brommie owner on here should crowd fund your experiment.



Excellent idea!


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## ianrauk (16 Aug 2017)

CharlieB said:


> Pardon my ignorance. What exactly are Tannus tyres, please?




Airless Tyres.. *HERE* you go


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## TheDoctor (16 Aug 2017)

They remove most of the risk and all of the fun. Like engaging in oral sex with a condom on your tongue.


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## Lee_M (17 Aug 2017)

CopperBrompton said:


> They are truly horrible things. Cornering on them in the dry feels like you're about to fall over at any moment. Gawd knows what they're like in the wet. Just fit Marathon Plus – I average one visit from the puncture fairy every 2000 miles.



The mileage you do these days thats about one every decade isnt it Ben?


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## Pale Rider (17 Aug 2017)

simon.r said:


> A few more miles this morning and I just couldn't take any more:
> 
> View attachment 367865
> 
> ...



Given a rear puncture is more likely - and more of a nusiance - than a front, it would have been interesting to know how the bike rides with a Tannus on the rear and an ordinary tyre on front.

I'm tempted to suggest that combination might ride acceptably, since the front wheel plays the major part in steering and braking a bicycle.


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## chriscross1966 (19 Aug 2017)

Pale Rider said:


> I'm tempted to suggest that combination might ride acceptably, since the front wheel plays the major part in steering and braking a bicycle.



Having learned to ride on a Raleigh Chopper I find I always brake on the back, the front is for emergency use only... A rear wheel skid was an acceptable cornering technique when I was ten, front brake locking came with a dentistry bill


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## Kell (21 Aug 2017)

Back brake to slow. 
Front brake (and back brake) to stop.


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## Yellow Saddle (22 Aug 2017)

The OP of this thread, Simon, kindly agreed to send me a couple of sections from his discarded Tannus tyre. I wanted to see for myself what the hype was all about and I quite frankly, found it intriguing that he hated these expensive solid tyres enough to cut them off after just a few rides. I received the sections, the original instruction brochure and some pins by post last week. Thanks Simon.

My initial thoughts for the request was to devise some sort of comparative rolling resistance test. At the time of my request I had to real idea of how I would do it so I opened a beer and gave it some thought, whilst mindlessly bouncing a superball against the wall. (That's how I'd like to phrase it for my post-Nobel prize interview). Then inspiration struck and I thought of the days when I played games in my workshop. Whenever I fitted a tyre I would finish off the exercise by throwing it away from me, onto the workshop floor and make it bounce back at me. It would magically bounce back because I put a hefty backspin onto it. It was my private little party trick. The trick revealed how much energy the wheel returned because the bounce is dramatically different dependent on the wheel configuration - inflation pressure, knobblies, slicks, sealant etc etc.

My inspiration was that I would bounce the Tannus and compare it to my own 25mm Conti at 60PSI. My inspiration had a flaw in it in that I only had a section of Tannus, now a whole wheel. Genious prevailed and I came up with the definitive ball-peen hammer trick. Instead of bouncing the wheel, I would bounce a hammer onto the tyre and see how much energy it returns to the hammer. Off came my front wheel and I started hammering it. I laid the Tannus flat onto a hard surface (granite kitchen top) and bounced the hammer on that. Same difference, give or take a large experimental error and poor eyeball technique. (This was after two beers).

Another inspiring moment hit upon me and I disovered that the Continental-shod wheel is actually losing more energy because I'm testing the entire wheel across its entire radius, through a set of spokes and into another complete tyre section. In other words, I should not bounce the hammer on top of the tyre when the wheel is standing on itself. I have to isolate a small section so that I only test one layer of tyre, not two and a set of springy spokes. I how positioned the wheel so that it hung off the corner of a workbench with the corner wedged between the spokes. Suddenly the hammer bounced really well. When compared to the Tannus I could just about convince myself that there was a dramatic difference and that the Tannus definitely had a higher RR than a pneumatic tyre and that I've proved it. I could just "feel" that the hammer bounces 1/10th of a mm higher from the pneumatic tyre than from the tyre. I've honed this "feel" after years of subjective compliance-testing of frames and wheels where I could "feel" that steel frames have about 0.3% more give than carbon frames and that 50gram lighter wheels gave me an edge of 0.5% on hills than heavier wheels.

Before publishing my findings in Scientific Bicycle Today, I procrastinated a bit and mulled over the results.

Another inspiration hit me between the eyes. Of course! Hysteresis (energy losses when rubber returns to a position before deformation), is not just caused by the deforming rubber against the road but also by other squirming, notably with tubular tyres, squirming against the rim itself. In other words, energy is lost by the compression inside the rubber and lost by the rubber (tyre) rubbing against the rim as your ride. This only happens with tyres which are either tubular (as in tubbies) or solid. Clincher tyres don't have these losses because they have to bottom to scrape against the rim in the first place.

Now I'm onto something, I said to myself. I then investigated the interface (fancy word for parts that rub) between Tannus and rim. It is hugely imperfect. The rim's shape only superficially matches the tyre's shape and to make things worse, the pins that hold the Tannus in place are spaced 50mm apart, leaving a large section not securely attached between the two pins. Here the tyre is a bit looser than directly under the pins, causing even more movement. If the rim doesn't have a flat spoke bed (none of them do), then there's a void between the Tannus and the rim itself, into which the rubber can morph in and out as you ride. More energy losses.

The third point of loss (if you've lost me so far, the other two were losses inside the rubber itself which is due to friction as the long curly chains or rubber polymer stretch and rub against other long curly chains of polymer and, squirming against the rim) is thanks to the generous (read stupid) tread on the tyre. It is really deep and causes large losses at the tyre's surface as the rubber squirms in and out of the voids in the tread. Had the tyre been designed smooth, it would have been better. However, then it would not have appealed to a naive consumer who believes that tyres must have tread.

So there you have it. These tyres have high rolling resistance because:
1) A rubber polymer always has higher hysteresis than a compressed gas.
2) The tyre does not fit perfectly into the rim and isn't attached with hard glue that prevents squirm.
3) There is thread squirm.

I have no idea how to test this, but a particular concern would be performance in the wet. Tyre rubber has been improved and improved for 100 years and still no better wet traction compound than carbon black has been found. Unfortunately, carbon black makes the tyre...err...black. Tannus are available in lots of colours, all chosen from the rainbow, which tells me there is zero carbon black in there. (How scientific is that deduction?)

So, (I've noticed on the radio that all scientists start answers with "so", so I'll do it as well), here are some pictures.







A_ scan from the information brochure showing you how to measure your rim width and choose the correct tyre. This means that fit is an approximation, unlike on a pneumatic tyre that automatically adjusts its fit. Room for improvement could include tyres more precisely matched to rims, better retention devices and perhaps even factory-fitting with hard glue.






A section of pins. These match the rim's internal width and apparently the tyres are shipped with a selection.






This is the pin fitted to the tyre. Round end facing downwards and pressed down on to click and hook behind the bead hook in the rim. Spaced 50mm apart.






Cross section of very expensive rubber. Note the tiny bubbles. To make the tyres sound like better value for money, these bubbles are called "nano voids". Note how the section intended to fit inside the rim will only approximate a rim's real shape and leave plenty of scope for squirming around, losing energy in the process.






A stupid quote hinting that the tyres contain some magic engine that kicks in at speed and somehow managed to reduce RR once in motion. Pure marketing genius. Ignobel Prize on its way.
_




_Gratuitous tyre tread that serves just one purpose - to increase RR. Actually, make that two, it also suckers people. 
_
And now I'd like to thank my producers, my dog, my co-author Et Al and of course Simon. Without them I would not be able to waste so much time.


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## Kell (22 Aug 2017)

I have to say, I'm glad someone else went for these rather than me. 

They seem like such a good idea in principle and I'd hoped that material technology had moved on from the solid rubber tyres you used to get. But it seems like either it hasn't, or the company that made these hasn't done made use of that technology. 

I do find it hard to believe that it's not possible to make them - and make them roll as well as a 'normal' tyre - but maybe it's cost that makes it prohibitive.


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## Fab Foodie (22 Aug 2017)

TheDoctor said:


> They remove most of the risk and all of the fun. Like engaging in oral sex with a condom on your tongue.


I'll take your word for that....


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## Yellow Saddle (22 Aug 2017)

Kell said:


> I
> 
> I do find it hard to believe that it's not possible to make them - and make them roll as well as a 'normal' tyre - but maybe it's cost that makes it prohibitive.


It is impossible to make them roll with as little resistance as a normal tyre. 

On a pneumatic tyre you are compressing a little bit of rubber (the thickness of the casing), flexing a bit of sidewall and compressing a bit of air. Collectively, this has less losses than compressing a solid tyre. 






The picture above shows why rubber has such high losses. These long molecules are matted like felt, and when stretched, they have to extricate themselves from the mat and this causes friction. It is like pulling on a piece of knotted string. When the pressure is released, it has to return to the original position and again, more friction as it settles in its bundled-up position again.

Air molecules on the other hand (or any other gas) are simple molecules that move about freely with very little friction between molecules. It's not cost, it is physics that makes it impossible. In addition, there's squirming, as explained above.


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## Kell (22 Aug 2017)

I'm not saying that rubber is the answer. 

Hence saying 'material technology' as opposed to rubber in my post above.


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## Yellow Saddle (22 Aug 2017)

Kell said:


> I'm not saying that rubber is the answer.
> 
> Hence saying 'material technology' as opposed to rubber in my post above.



The only material I can think of is Unobtanium. Perhaps you have better suggestions.


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## Kell (22 Aug 2017)

I have no suggestions. This wasn't meant to be a Dragon's Den pitch. I just said I find it hard to believe it's not possible to create something which isn't a rubber tyre full of air.


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## Kell (23 Aug 2017)

Something like these: 

(Again, I've no idea how they perform or compare to traditional tyres) 


View: https://www.youtube.com/watch?v=8hi5i-UODAE


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## TheDoctor (4 Sep 2017)

Looks like the same thing but even more precariously mounted.


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## Bodhbh (4 Sep 2017)

simon.r said:


> I don't have the Tannus removal tool and after a few minutes of trying to use a pair of grips as a substitute decided that I've wasted enough of my time on these tyres and resorted to a hacksaw and Stanley knife.



Put them on eBay bundled with a roll of duct tape and starting bid of a quid and see if anyone bites.


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## Bill (11 Sep 2017)

Many thanks for this topic. I ordered my Brompton on Saturday from the main dealer in Birmingham. The sales chap introduced me to these tyres. I took a lot of convincing but purchased them. Reading here about the 'grip' and noticing the lack of central rubber channelling moulded on the tyre at the shop, has made me think about nipping back into Brum to cancel them! I REALLY cannot afford to come off the bike as I take Warfarin. Two weeks ago I cut the back of my right leg on the studs on my platform pedals (since removed) The blood poured out and continued from under the six by four plaster I put on. I have since purchased a aerosol of Boots 'spray plaster'.....jezze


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## Bill (26 Nov 2017)

Sorry to have to say this but I don't have a problem with the Tannus tyre on my new H3R. Maybe there might be a bit of rumbling?? felt through the saddle, but getting along seems alright to me. I am Easy Rider type of cyclist so speed is not important to me at all.


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## simon.r (26 Nov 2017)

Bill said:


> Sorry to have to say this but I don't have a problem with the Tannus tyre on my new H3R. Maybe there might be a bit of rumbling?? felt through the saddle, but getting along seems alright to me. I am Easy Rider type of cyclist so speed is not important to me at all.



Fair enough. I didn’t like them at all, but if they work for you that’s good


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## Kell (27 Nov 2017)

TheDoctor said:


> Looks like the same thing but even more precariously mounted.



Just watched this vid: 


View: https://www.facebook.com/futurism/videos/807626099416591/


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## TheDoctor (27 Nov 2017)

Well, they're pretty graphics, I'll give them that.
Whether any of them will ever make it into the real world...


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## stoatsngroats (17 Aug 2018)

Yellow Saddle said:


> The OP of this thread, Simon..../..... I could "feel" that the pins that hold the Tannus in place are spaced 50mm apart, leaving a large section not securely attached between the two pins. Here the tyre is a bit looser than directly under the pins, causing even more movement.
> 
> So there you have it. These tyres have high rolling resistance because:
> 1) A rubber polymer always has higher hysteresis than a compressed gas.
> ...



@Yellow Saddle, and @simon.r 

Many thanks for the joint efforts to advise on these tyres, it has been a real pleasure to read all the accounts in this thread.

I’m about to enjoy a Brompton, and was considering these tyres, as the thought of never having to repair a flat is quite engaging.

I can understand the issues with Yellow Saddles review, particularly the void underneath the suspended tyre, and the squirm that will result there, and I really get the issue with compression of gas, compared to some kind of material compound, and I can appreciate these will combine to increase rolling resistance.

None of the research you’ve done was a waste, as I’ll just run Marathon plus, and hopefully not have too many issues.
Cheers to you both!


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## Racing roadkill (17 Aug 2018)

Yellow Saddle said:


> The OP of this thread, Simon, kindly agreed to send me a couple of sections from his discarded Tannus tyre. I wanted to see for myself what the hype was all about and I quite frankly, found it intriguing that he hated these expensive solid tyres enough to cut them off after just a few rides. I received the sections, the original instruction brochure and some pins by post last week. Thanks Simon.
> 
> My initial thoughts for the request was to devise some sort of comparative rolling resistance test. At the time of my request I had to real idea of how I would do it so I opened a beer and gave it some thought, whilst mindlessly bouncing a superball against the wall. (That's how I'd like to phrase it for my post-Nobel prize interview). Then inspiration struck and I thought of the days when I played games in my workshop. Whenever I fitted a tyre I would finish off the exercise by throwing it away from me, onto the workshop floor and make it bounce back at me. It would magically bounce back because I put a hefty backspin onto it. It was my private little party trick. The trick revealed how much energy the wheel returned because the bounce is dramatically different dependent on the wheel configuration - inflation pressure, knobblies, slicks, sealant etc etc.
> 
> ...


Absolute bull. Try them and then comment.


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## Racing roadkill (17 Aug 2018)

Getting them off is easy. Put the largest of the Allen keys from your multi tool through the bit where the fixing pins go, then put the fitting tool through the gap and roll it over around the circumference. The pins snap out with no damage to the rim or tyre.


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