Monday, 22 August 2011

Collecting stock

The trailer's own weight plus twelve frame mounted front racks for stock together came to 42 kg

Today I went to collect some more racks for the shop. I thought a bit about this. Pulling the trailer behind the Mango obviously slows it down. While the Mango itself is aerodynamic, the trailer is not. It's a bit like pulling a parachute.

It is difficult to calculate the effect due to aerodynamics, but the effect of the extra weight of the full trailer on the return trip is very easy to notice and that's easy to calculate by looking at the online calculator. This shows that the effect of the weight alone takes about 5 km/h off my speed or, if you like, makes the journey feel like it is 15% "longer". However, the round-trip of 75 km still took well under three hours, which isn't so bad with a heavily loaded bike.

Here's a short film of the ride to the factory and back:

Sunday, 21 August 2011

Our Xtracycle - How your parcels start their journey

Explanatory captions on this video are only visible if you watch on a computer and not on a mobile device.

We've owned an Xtracycle Freeradical since 2003. Attached to a fairly basic mountain bike, it's done a lot of work in the past. However, for the last two years, our Xtracycle had fallen out of use. We both had become used to the comfort of Dutch town bikes, and as a result, we were more likely to pile parcels high on our town bikes, sometimes pulling a trailer as well, than to ride the Xtracycle. When I rode it last December, I noticed that the chain was worn and several things felt a little unpleasant, so work needed to be done.

Recently the sales in our online shop have built up and the option of moving all our parcels on the normal town bike had become quite unworkable. We needed a cargo bike again. Over the last few weeks I've done quite a few small jobs on the Xtracycle to get it in usable order once more.
Fundamentally, much of what was "wrong" with our Xtracycle came down to it being a mountain bike with a thing bolted onto the back.

Now I know that many people love their mountain bikes. There is no reason why they should not do so. Mountain biking is a fine sport. The problem isn't mountain bikes, or their riders, but the use of the wrong tool for the job. Mountain bikes are not particularly practical bicycles. MTB gearing is rather on the low side, which is fine for travelling through mud or up steep slopes, but not ideal around town. The sitting position is uncomfortably stretched out due to the long stem and straight handlebars. The high bottom bracket, useful when riding off-road, is a nuisance in town as it requires that one hops down off the saddle at stops. MTBs don't come with mudguards, chainguards or racks, which can be tricky to fit. A kickstand isn't fitted, and permanent fitting of lights is not straightforward. A practical bike needs to have nothing on it which must remove when you park.

Many of the problems with using a mountain bike for everyday transport can be solved with suitable add-ons, and by doing this one can approach the concept of a practical Dutch everyday bike, which comes fitted with everything you need for practical use without requiring work to be done.

Some of the issues are tackled by the Xtracycle Freeradical add-on itself. It provides an oversized rack. If you also fit the Xtracycle specific kickstand then that solves another problem as the bike can now stand upright without assistance. These two things we'd already done. However, the problems that remained with our Xtracycle were typical "MTB as town bike" problems, which have now been put to rest as well as possible.

For a start, the tyres. Knobbly tyres are designed for mud. They're also OK in snow. However (with just a few exceptions) they are inefficient and slow on smooth surfaces. Also, cheaper tyres are puncture prone. There are various add-on products available to try to reduce this problem, but far and away the most effective way of reducing the problem of punctures is to fit better quality tyres with a good anti-puncture layer. I chose the Schwalbe Marathon tyre. It's not fast like a racing tyre, but it's faster than typical knobbly tyres, and puncture resistance is very good. This also makes the bike blissfully quieter to ride as you don't get the characteristic hum of a knobbly tyre on tarmac. While on the subject of wheels, another essential for everyday riding is to fit mudguards (fenders). Because I don't like spray on my feet and shoes, I also fitted the larger and truly effective type of mudflap.

Only half a mudguard is fitted at the back. Sadly, my original model Freeradical had no really good way of mounting a rear mudguard. I understand that eyes for mounting a mudguard are provided on newer versions of the product.

To achieve more comfort when riding the bike required changing the handlebar and stem and also the saddle. My handlebar and stem are a set which we already owned which is equivalent to the combined handlebar and stem in the webshop. This change brings the handlebars a lot closer so that we don't have to lean over so much when riding and the cargo is closer to the turning axis, so the bike is easier to control when heavy. Also, the ends of the bars turn backwards, which is much more comfortable for the wrists than a straight handlebar. The saddle is the same wide sprung and comfortable model as we'd already got on other bikes of ours, and as used by so many people who want comfort and practicality.

Our Xtracycle is fitted with a Steco front rack for extra capacity. This works very well, but it also makes the steering more likely to flop around when the bike is on its stand. For that reason I have fitted a steering damper to the bike. I'd not used one before, but I find that it works very well with the rack. The handlebars no longer turn so much when the bike is parked, and so weight in the front is less likely to flip the whole thing over. It also has a benefit when riding as it tames the front end a little, which is helpful when there is a lot of weight on the rack.

I've also fitted dynamo lights to our Xtracycle. They've a huge advantage over battery lights in that they are permanent, bolted on, part of the bike so don't have to be removed when you park and there are no batteries to be flat. This is essential for practicality.

I'm using a Nordlicht dynamo attached with a special bracket for the V-brake boss, coupled with a Basta headlight mounted on the light bracket built into the Steco rack. There are brighter headlights for use on long rides in the countryside, but that's not what we use our Xtracycle for. For use in town, this provides more than enough light for a very reasonable price. The rear light is difficult with the Xtracycle. Again, there is no good place to attach a light to the Freeradical frame. I've opted for a DIY solution using an old battery-powered rear LED light adapted for dynamo use and attached to the bottom of my saddle.

I would have liked to fit a Dutch style lock to the bike. These are by far the most convenient and quick to use style of bike lock, but they don't fit with the Freeradical in place. Instead, I found a way of mounting an old D lock permanently on the bike. A hole drilled in the advertising board allows the D lock to be swung into the wheel. It also stays in place above the top tube while riding. It's not the highest security arrangement, but it's enough around here.

The triple crankset (22/32/42 teeth) which was originally fitted to the mountain bike which we used as a donor has been replaced with a single speed crankset with 46 teeth. This gives higher gears for a bit more speed in town.

Finally, a bell. Of course, for a large bike there is just one choice - the 80 mm Ding Dong bell.

And how has it turned out ? Well, now the bike is once again enjoyable to ride, and over the last few weeks since the work was done, it's been used several times.

Sunday, 14 August 2011

Tacx Jockey Wheels Long Term review

Back in 1998, the jockey wheels in the derailleur of my recumbent bike of the time were worn. The derailleur still functioned, but there was noise from these very small parts on the bike. A friend suggested that I try Tacx replacement jockey wheels which he'd found made a significant difference to reliability of his mountain bike.

I bought a pair, installed them in the derailleur I was using and rode on. Problem solved.

A few years later, the first derailleur was damaged and I moved the to another derailleur on a different bike. Time passed. I rode a lot of km, made many tours, including Land's End to John o'Groats with these jockey wheels spinning behind me the entire time. Everything worked and I forgot about them.

Last year, the derailleur on that bike also became damaged and I replaced it. When I took the old derailleur off, I found my tacx jockey wheels again. They didn't fit in the more modern replacement derailleur (new ones do), but as they still seemed OK I kept them in case they were useful later. This week I decided to take a closer look at them:

One has a little play in the bearing, which makes a bit of a gritty noise. The other still seems to be perfect. They still spin better than standard wheels in almost any new derailleur. The worn look on the outside is largely due to the teeth having worn away. However, teeth on jockey wheels aren't really that important. Some old derailleurs had round jockey wheels without teeth, but they still worked as derailleurs.

Needless to say, I'm impressed by the longevity. Mine were the lower cost type with the normal bearings. Now there are variations with stainless steel and ceramic bearings. Good quality products like this are exactly the sort of thing we set our shop up to sell. We don't like gimmicks. We like products which are reliable and long lasting.

If you've got worn jockey wheels in a derailleur, it's a lot cheaper to replace just the wheels than the entire derailleur. We now sell a selection of different types to fit most derailleurs.

I'm now testing ceramic Tacx jockey wheel in the Mango. While my old ones look odd with the teeth missing, I don't think it's that important. I've got one very old derailleur with round jockey wheels which never had any teeth at all.

Wednesday, 1 June 2011

Choosing between inner tubes and pumps

Few people pay much attention to inner tubes. They're a bit boring. You can't see them as you ride. Actually, it is quite reasonable that most people pay little attention to them, as most of the time the differences between quality inner tubes are slight, and for most people they don't matter.

However, there is a difference in the construction, and some are better for some purposes than others. I've currently got three different inner tubes in stock which are suitable for relatively narrow 20" (ETRTO 406) tyres. This is how they differ:

The lightest of the bunch is the Schwalbe SV6A. These have a claimed weight on the packet of 65 g, and that's exactly what my kitchen scales say they weigh.

This inner tube is the lightest of the three, and also feels most supple. I have not tested rolling resistance with this inner tube, but if there's a difference you can expect this will be the best performer.

It will probably also lose pressure faster than the other options, so you'll need to pump up your tyres more often with this inner tube. Also, maybe it's less damage resistant too.

Reflecting its special status, the SV6A costs an extra €2.38 over the price of normal Schwalbe inner tubes.

The second lightest is also a Schwalbe - the SV6. It says nothing on the box about the weight, I found it to be 95 g.

This is a standard grade inner tube from a quality manufacturer. It's still actually quite a nice supple inner tube, and it's what I have in the front tyres of my Mango at the moment.

Either this or the Continental are a good choice for everyday use.

The heaviest of the three is the Continental Compact 20 inner tube. Continental make extra thin high performance inner tubes (akin to the SV6A) in other sizes, but not for 20" wheels.

This is again a standard inner tube from a quality manufacturer, which again means it is actually of good quality. According to my scales, it weighs 100 g, which is an irrelevant difference over the weight of the Schwalbe equivalent.

The construction of this inner tube is a bit different. The rubber feels thicker than the Schwalbe SV6, though given that they're about the same weight it obviously can't really be so different.

What is a little different is that the Continental is wider than the Schwalbes, even though it's only rates as being suitable for tyres up to 32 mm wide, while the Schwalbes are for tyres up to 40 mm wide. This makes it a little more difficult to fit into a narrow tyre. Continental also specify that their inner tube will also fit 451 size wheels, while Schwalbe suggest theirs will not.

Either this or the Schwalbe SV6 are a good choice for everyday use.

In practice, I find the Continental is a slightly awkward fit even within Continental's own 28mm wide tyres. It's just a bit too wide, and makes it more difficult to fit the tyres. As a result, I'm using the Schwalbe SV6 in those tyres at the moment. If I were racing, I'd use the SV6A as it is slightly lighter, and more importantly it is reckoned that due to its flexibility it will roll a little better. I'm using a Continental inner tube in my rear tyre, which is a bit wider than they recommend, but here it seems a good fit. I also carry a Continental as one of my spares spare (I have two for personal use).

I also weighed a few no-name inner tubes for the same wheel size. Most weighed about 130 g, but one was 200 g - a surprising difference. There is almost certainly a difference in performance between such an inner tube and those from the better manufacturers.

Valve types
Presta / French / HP valve
Another difference between tubes on offer is the type of valve in use. Some people have very strong feelings one way or another. It can be nearly a religious issue. However, I think each has its place

For racing, when you might actually care whether the pressure in your tyres is up to the maximum and want to measure them, there is an advantage with the Presta ("French") valve rather than the Schrader (car type) or Dunlop (also known as Dutch or English) valves. Also, as everyone else will be using these, if you borrow a pump it will already be set up to fit these valves.

Dunlop / Woods / Dutch valve
However, unless there is a special reason to choose, all three types keep the air in equally well, so most of the time it's best to use what's convenient and what you're used to.

In the Netherlands, there are sometimes publicly accessible pumps designed to accommodate the Dunlop valve, and you can buy very well priced floor-standing pumps which make pumping these up very easy indeed. The perfect choice for everyday cycling.

Schrader / Car valve
I use Presta valves for sportier bikes and Dunlop valves for our town bikes.

As much as possible, I avoid the Schrader type as they're most difficult to push the pump on and off, and due to the larger area of pressure they're the type which most often gives problems with keeping the pump head on the valve while pumping.

However, I might feel differently if this was the most commonly used valve type where I lived as the convenience would then be on the side of the Schrader. In the US, these seem to be the most popular valves in use so they perhaps make sense for everyday cycling.

Fitting Presta valves in Schrader rims
Adaptor to use presta valves in
schrader rims
For many people, including myself, the Presta valve is the best choice for higher performance bikes. However many wheel rims come ready drilled for the larger Dunlop and Schrader valves. It's common for people to use Presta valves in such rims and despite the difference in diameter it usually doesn't cause a problem, but inner tubes are sometimes damaged when abused in this way. For this reason, we now sell an adaptor to convert between valve sizes. This fills the larger hole in the rim and makes it safe to use Presta valves.

Pumps
Some of you might have noticed that for a long time now we've had a bike parts and accessories shop which didn't sell any bicycle pumps. I've now added two floor-standing pumps to the shop website, including one which is light enough to take along with you, if a little bulky. However we still don't have a truly portable small pump.

They seem an obvious thing to have, so why not ? The problem is finding a product which we can trust ourselves. We said from the beginning that we'd only list things that we either already use ourselves, or that we'd happily use ourselves. This is what we're sticking to.

One pump which we don't recommend and won't be selling is the SKS Airboy.
SKS Airboy. Don't buy this, even for just £1.
I bought my "Airboy" at the Mildenhall Rally, probably ten years ago. It cost me the grand sum of one pound. At the time I thought this was a bargain. However, it's too flawed to be useful. It has a double headed design with one side for Presta or Dunlop valves and the other side for Schrader. The pump relies on air pressure to keep a small rubber ball in a position to block the pump head that you're not using.

There are a number of problems with this idea. Usually, this means you can only pump upwards as initially gravity has to put the rubber ball in place. That may not sound like a big issue, but it becomes one as soon as you try pumping up tyres on a bike with laden panniers or a coat guard. However, the problems go beyond this issue. The heads don't fit well on valve stems for any of the three types of valve, and it's impossible to pump tyres up to an adequate pressure without the pump popping off the stem.

This problem hit me a few weeks ago when I got a puncture on a ride. Before leaving I'd picked up a pump to take with me, but not until I got the puncture did I discover it was this pump. At first I thought it would be OK, as in the past, I'd managed to get just enough air into a tyre with this to at least ride to a bike shop, but not this time. I had to walk a distance and ended up buying a working pump at a bike shop.

Anyway, I bought it ten years ago, so why am I writing about it now ? You can still buy these ! I've seen the exact same model for sale this year. To double the insult, in the last few days I accidentally bought another pump with exactly the same problems. We need something sensible and usable in the shop, so I added what seemed to be a well speced, but also well priced pump to an order from one of our suppliers. When it arrived, it turned out to be an SKS under a different name, with a variation on the same kind of head. It has exactly the same issues as the older one, plus a new problem: A spring works against you for almost half the stroke, making it difficult to achieve much pressure even if the pump would stay on the valve.

SKS used to be a very good name for pumps. I've a few old ones which work very well, and I'm sure they also still produce good models. However, I'm currently waiting for a different manufacturer's pump to turn up from a supplier. It's not fancy and expensive, because portable pumps tend to get damaged or lost. But if it works well it will appear on the shop website in a few days.

Saturday, 21 May 2011

Continental SportContact tyre

I'm now trying Continental's
SportContact tyres. These will
stand up better to everyday use.
For a few months now I've been riding with Continental Grand Prix tyres on the front of my Mango. They're lovely lightweight and fast tyres, but unfortunately I have to say that they've not really worked out, at least on this bike. I used my pair briefly last year before removing them for winter, and re-fitted them only about a month ago. They've been used for about 800 km, which is not all that impressive.

The main problem, I think, is that they are simply not intended for use on a fast tricycle like the Mango. Sideways forces, especially when braking, are too much for them. On a two-wheeler it isn't possible to put such a sideways force on a tyre, nor to brake with a considerable sideways force on the front wheels without instantly falling off. The rubber was lost right outside our home, as I rode in quickly. A touch on the brakes, the wheel on the inside of the turn was in a skid, and there was a smell of rubber.

Even if I'd not had this problem, I was already planning to replace the tyres. Both Grand-Prix tyres already had cuts in them presumely due to small stones or pieces of glass (I didn't find the cause). This all happened a bit too soon for a practical tyre.

Continental's Grand Prix tyres are
fast, but don't like high speed
cornering and braking with a
velomobile.
I've not given up on Continental, but have replaced the Grand-Prix with the Continental SportContact. These are the same size, 28-406, but they are designed for everyday use. They weigh a bit more, have a bit more rubber, have the "SafetySystem" anti-puncture protection, sidewall reflectors, and a lower cost. they're also still supposed to be fast. It sounds like a promising combination, so I'll see how I get on with them over the next few months (The Sport Contact was a very good tyre - it's now been replaced by the Contact Sport).

The advertised weight for the SportContact in this size is 295 g, however mine were actually a little lighter at about 270 and 280 g each.

New tyres fitted and ready to go, on a cycle path wide
enough that riding an unusual bike is never a problem.
One very nice thing about both the SportContact and the Grand-Prix is that both are easily mounted on and removed from the rim without tools, and both sit well on the rim and run true straight away. This can be quite difficult to achieve with some tyres.

The maximum pressure stated on the side-wall on the SportContact is 6 bar ( 85 psi ), but the accompanying paperwork attached to the tyre says 7 bar ( 102 psi ). I'm using the higher pressure. I have suspension so don't need the tyres to contribute too much to comfort, and they'll roll faster at the higher pressure.

My rear tyre remains a Schwalbe Marathon Racer. This still barely looks run-in. Actually, it wouldn't have been a bad choice for the front wheels as well.

Update 2016
When my daughter and her boyfriend went touring, they used Continental SportContact tyres.

Tyres and tubes and other nice stuff can be bought at our webshop.

Monday, 21 March 2011

A touring toolkit

Unless accompanied by a car carrying equipment, cycle tourists need to be self sufficient to some extent. You can't predict when breakdowns will occur. Obviously what tools you carry with you depends on how far you're going and what you think you'll need. Weight is always an issue.

Unless I'm just riding into town and back, I always carry tools with me. A few days ago I decided it was once again time to check that the contents of my tool-kit still made sense. A few items had been used up, like patches, and a few tools needed to change for my new bike.

Everyone travelling any distance will surely carry a pump and spare inner tubes. However, other things are also useful to have. Even on shorter rides, the walk home or to the nearest bike shop can take quite some time, but when riding longer distances and if you may be a longer distance from "civilization" then it's even more important to be well prepared.

At the moment, my toolkit contains the following:
  • Multi-tool. This is actually the only new thing in my tool-kit. A Beto multi-tool. It includes all the sizes of spanner, screw-driver and Allen key which I may need. Previously I had to carry more than one such tool to cover everything.
  • In the past I also carried a separate chain tool, however my new multi-tool includes one, so that saves a bit more weight.
  • The puncture repair kit is a Rema Tip-Top kit. I've used these for years as they have, in my opinion, the best quality patches. This one has been part of my kit for years, but is newly stocked with patches and glue.
  • When removing and refitting tyres, it is best to do so without using tyre levers as they can damage the tube further. However, if you have tight fitting tyres, or you find yourself doing the work with cold and wet fingers then a good set of tyre levers are well worth having. The Schwalbe tyre levers are well shaped, and wider than most, which minimises the risk of damage. I've had this set for years and they work well.
  • Well made wheels shouldn't go out of true in normal use. However, accidents happen and I like to be prepared. Spokey Spoke Keys are perhaps the lightest weight good quality spoke key. Mine has had a lot of use over the years, both building wheels at home as well as straightening them on tour. Usually in order to keep moving with a single broken spoke you merely need to slightly loosen off the two spokes either side of that which is broken so that the wheel straightens out. However, carrying a few spare spokes of the correct size means that replacements can be installed and the wheel can be made perfect again quite quickly.
  • A little duct tape wound onto a stick, some bendable wire, and a few zip-ties don't weigh much and don't cost much. However, they can be used for many repairs. In the past I've used tape to hold together broken lights, zip-ties to affix mudguards and wire to keep on a heavily loaded rack.
  • The white "paper" in my toolkit is actually cut out of a Tyvek junk mail envelope. It cost nothing and weighs almost nothing, but it is strong enough to make an excellent "boot" to put between inner tube and tyre in the event of a bad cut.
  • A pocket knife includes a few tools that the others don't have - such as scissors to cut the Tyvek, a sharp knife which can be used for a range of things, and a bottle opener which is rather a nice thing to have with you for a beer at the end of a long day.
Things not shown in the photo include the inner tubes (I carry two, and do any puncture repairs needed at the end of the day if possible), a spare folding tyre in case of damage to a tyre, chain links to join a broken chain, and a spare brake cable. Of course, I also carry a pump.

Different people have different ideas, of course, and some like to travel lighter than others. We've put our suggestions for a touring toolkits in a special section of our webshop.

Wednesday, 16 March 2011

Kick Stands and Tyre Pressures

Spanninga Easy 30 mm version
The kickstand failed on one of our rental bikes at the end of last year.

A bicycle which falls over unless leant on something is a nuisance, even just in storage, let alone in use. Leaning on brick walls causes damage to the bike. Other surfaces can be damaged by the bike. Therefore, I've replaced the broken part with our favourite type of single sided stand, the Spanninga Easy kick-stand. This is a long stand which is sturdy enough that it will support quite heavily laden bicycles safely.

Luckily, with most bikes, fitting a kickstand is an exceptionally easy job to do. It fits to the bracket provided as part of the frame, with one bolt just in front of the rear wheel, and just a single tool is required to do this - an 8 mm Allen Key.

The stand simply has to be held in position with one hand, while the bolt is done up with the other. It takes just a couple of minutes to do.

It's a good idea to put a little grease on the thread of the bolt so that it won't seize up over time, and to put some on the mechanism of the kickstand as well to make it run a bit smoother.
Most bikes use the "30 mm" version of the stand. Dimensions of both variants are in the web shop.

Bike with working kick-stand, so which no longer has to be leaned on something.

And now something about tyre pressure and tyre choice...

The bike in the photos above is fitted with the same tyres as I've currently got on my Mango for winter commuting - the Schwalbe Marathon Plus. The great advantage of these tyres is that they are virtually impossible to puncture. As a result, they're our choice for most of our bikes, most of the time. If you prefer riding to repairing punctures, these are the tyres to go for.

They're also quite fast tyres... but only if pumped up quite hard. I realised on Sunday morning that after months of riding the narrow Marathon Plus tyres on the front wheels of my Mango were well under the maximum recommended pressure of 6.5 bar ( 100 psi ). In fact, they'd got down to about 5 bar ( 75 psi ) which is low enough that they roll much worse. I'd been disappointed by my speed of late, but of course pumping the tyres up to the recommended pressure restored their previous performance.

It's one thing to have to stop and fix a puncture in the middle of the summer when it's warm and the sun is shining, but something else altogether in the winter when it's dark and cold. That's why I use them especially in the winter.


But now it's just about Spring... and Summer is around the corner. This time of year, punctures are less likely, and in any case I don't quite so much if I get them. Soon, I'll take the Marathon Plus tyres back off my Mango and replace them with something which is a little more fun to ride with. For everyday summer use, I intend to switch to the the Marathon Racer. They still have a puncture resistant layer, so punctures should at the least be rare in summer conditions, but it's a much thinner one making them lighter and faster rolling than the Marathon Plus. They're well suited for everyday riding.

For racing, I've a pair of only slightly worn in Continental Grand Prix tyres for the front, or perhaps Stelvio or Durano. These are all nice fast rolling, narrow, durable, puncture resistant and light weight tyres with decent grip on the road, and should work well combined with a Marathon Racer on the rear.

Repairing a puncture in a
Comp Pool which I fitted
to Judy's bike
However, I've also some more unusual tyres which I might use again, but only if the right opportunity presents itself: Three Avocet Fasgrip tyres. These are a real curate's egg of a tyre. They're fast, they're durable, but they have a magnetic attraction for sharp objects on the road so you get lots of punctures. The lightest sprinkling of rain results in no grip whatsoever, and even more punctures. I don't sell these. I don't think I could live with myself if I did. However, a colleague of mine at the Ligfietsgarage sold them to me personally (they don't sell them to the public either), describing them as "just like the Tioga Comp Pool". I should have taken this as a warning, but of course I'm a glutton for punishment so I instead took it as a recommendation. He was absolutely right. They really are just the same. I should have known what I was letting myself in for. But with both of these tyres there's a pay-off in the right conditions in that they do genuinely have low rolling resistance - so long, of course, as they're pumped up to their recommended pressures, plus a bit more if you're really daring... I raced with the Avocet tyres last year.

Tioga's Comp Pool is long out of production. I thought the Avocet was out of production too but it's still on the manufacturer's website. Occasionally someone comes out with a new tyre which is described as "just like the no longer available Tioga Comp Pool". Sensible people run away when this comparison is made... Speed without such compromises comes from the more sensible tyres which I mentioned earlier.