Cycling UK Forum

I have been using the same tyres as insanityideas but have just gone back to 1.75" for the slippy season. I was losing traction too often on mud etc on the hills. It was pushing it a bit on a shopping bike with trailer round farming country. They will go back when summer comes again.
The tyres are fitted to Sputniks and I have no difficulty removing or fitting them. However I am very carefull about pushing the part of the tyre at the other side of the wheels DIAMETER well into the rim well and getting plenty of slack in the tyre when you need it.
The ultras were only on for 800miles, no punctures.

Cunobelin wrote:Of course the bad news is that you cannot explain the extended pub visit wit "I had a puncture on the way home" as the SO will no longer believe you!

You don't need to say that you've got marathon pluses do you now?

I've got marathons on the back of mine and I've actually had a couple of punctures so they're not perfect.

fatboy wrote:

Cunobelin wrote:Of course the bad news is that you cannot explain the extended pub visit wit "I had a puncture on the way home" as the SO will no longer believe you!

You don't need to say that you've got marathon pluses do you now?

I've got marathons on the back of mine and I've actually had a couple of punctures so they're not perfect.

That's why it is bad news......

I have the plus 700C 25s on my light single speed (sport-racing geometry) commuter for more than a month now. Despite the carbon forks ride became rather harsh with these tyres compared to the old 26 Kendas.

I have to say that putting them on was very difficult on a narrow racing rim.
Although they feel heavy I don't mind it. Knowing that they are puncture free is the most important thing in cold winter months.
If you ever repaired a puncture under pouring rain (and you still have to go to work in good time), you know what I mean!

I think they are good for leisure use as well as last thing I want to do while I pull my daughters trailer is a puncture.
They seem to have lots of grip as well compared to my 700x 26 Kenda tyres. Overall I'm very happy with the Marahon plus. I'd personally keep them on 4 seasons if they are as good as they claim.

I have done a couple trips to work and back now on the new tyres, I think much of this praise is going to be down to how skinny and low profile the tyres are compared to my old ones, rather than something remarkable about the tyre technology. BTW all references to speed are valid, as I use a GPS bike computer and therefore don't have to worry about changes in wheel circumference.

The Continental UltraGatorskins with duraskin+K (26x1.125) compared with Specialised Nimbus with flackjacket (26x1.5):

+Gatorskins are a lot faster, and the bike is much more reactive to steering input (not twitchy, but you have to be careful not to over egg it).
+Bike appears to pick up speed better, and carry it more easily.
+Lower profile of the tyre makes the wheel a smaller circumference and has affected gearing, I now run out of gears going downhill (this is a 5mph difference in top gear)
+In wet and dry tyres have more grip, and don't seem to snake around when skidding the rear.
+I can't get to 120psi recommended pressure with my track pump, I am not heavy enough.
+going over stones tends to result in an alarming ping sound as the chip flies out from under the tyre, and an unsettling sideways motion.
+The wheel will now fit into the slots of an incorrectly aligned road drain.

Still to check:
+performance on mud, grass, leaves, gravel and other unexpected surfaces that a road cyclist may be forced onto.

Good news is the increased grip that I bought them for seems to be there, and a zippier bike is a side effect of their size rather than tyre construction.

At some point I will have to finish wearing out my Specialised Nimbus tyres, which is going to take a looooong time, and means going back to a heavier ride.

The difference in gearing is very noticable as is the weight difference in my case.
The recommended pressure is 95psi, 120 is the max pressure.
I had never associated the way they shoot stones out the side with the ultragators in particular but I think you could be right. It is quite impressive, I even hit a friends top tube once.
It is the dirty, slippy cows**t covered roads that made me take them off.

zenzinnia wrote:Put a little air in your tube when re-fitting the tyre to stop catching the tube when the tyre goes back on.

UltraGs do seem to be tight - I often have problems getting them off my rims (Alessor Endeavours - now Rigida Sputnik) but I had put this down to the deeper, thicker rim.

I have exactly the same combination (Ultra Gs on Sputniks) but managed to get them on with minimal effort and bare hands. Seems a bit strange to me!

insanityideas wrote:+Bike appears to pick up speed better, and carry it more easily.

have you any idea what your averages where like for your commute before and after the new tyres? It'd be nice to have some figures on it as I'm planning to go from the Nimbus Armadillos to those tyres for exactly the same reasons.

...also if you have too much spare time (!) what is the rolling circumference of the tyres? My Nimbus where about 1960mm. If you sit on the bike with the valve at the lowest point of the tyre then roll forward until it's at the lowest point again and measure the distance.

Cheers!

WesBrooks wrote:have you any idea what your averages where like for your commute before and after the new tyres? It'd be nice to have some figures on it as I'm planning to go from the Nimbus Armadillos to those tyres for exactly the same reasons.

...also if you have too much spare time (!) what is the rolling circumference of the tyres? My Nimbus where about 1960mm. If you sit on the bike with the valve at the lowest point of the tyre then roll forward until it's at the lowest point again and measure the distance.
Cheers!

Ah you sound like a man after my own heart when it comes to collecting useless statistics. So far although I have done a few commutes since fitting them I have only done one over my usual route.

My usual route is very hilly and 6 miles each way, consequently there are times when I get up significant speed for a decent period of time. There are no flat bits, but many traffic lights to stop for. The best round trip time (not including stopped time) I did on the Nimbus's was 1hr 3min. First trip on the Gators I managed 1hr dead. I would estimate I was probably not trying quite as hard either. On this type of terrain that equates to about 0.3 mph increase in average speed. If your ride is flatter, more consistent, or with fewer stops I would expect to see a more substantial improvement, due to the efficiency savings which I am not able to fully take advantage of as quite often I am fighting gravity, dumping energy into the brakes or steaming away from traffic lights.

When I get the chance to next go along the nice flat Bristol-Bath cycle path I will be able to give you some stats on that... but don't expect that any time soon!

I use a GPS bike computer, so none of the info has been affected by change of wheel circumference... what this also means is I haven't measured it yet.. But I can do, when its daylight and not raining outside. To give you an idea... placing a wheel with nimbus on against a wheel with gator on, the top tread of the gator was almost at the rim edge of the bigger wheel. As a very approximate this is a reduction of 3cm in diameter of the wheel.

In practice the change of gearing caused by change of wheel circumference seems to equate to being two gears higher on the rear cassette when in the big ring on a mountain bike. Rather annoyingly this means its very difficult to peddle above 25mph... and I am considering seeing if Shimano do a hyperglide sprocket smaller than 11 tooth.

To answer the other comments about them being rather tight... some of my tyres are very tight on the rim others rather loose. Just depends on luck a bit. I did chuck some air in the tube to stop it getting caught, but the gators have a ridculously small amount of space inside of them so you can't add too much air!! I would definately recommend the smallest size inner tubes you can find.

My UltraHamsterSkins lasted two weeks before I threw them away in disgust. I had a couple of punctures and then found the entire tyre was filled with shards of embedded glass.

They may be OK if you leave them to mature for a year or so - I have some really old Specialized tyres with no kevlar, no soft rubber protection belts, 20mm, very thin tread and they have never, ever punctured over several sets. The tread is too hard to embed glass (it's actually slightly crazed) and they have a high TPI.

insanityideas wrote:In practice the change of gearing caused by change of wheel circumference seems to equate to being two gears higher on the rear cassette when in the big ring on a mountain bike. Rather annoyingly this means its very difficult to peddle above 25mph... and I am considering seeing if Shimano do a hyperglide sprocket smaller than 11 tooth.

It sounds like you need a bigger chainring, as even Sheldon Brown doesn't list 10-tooth sprockets!

If you leave the small ring alone, you'll still retain your existing climbing ability.

WesBrooks wrote:have you any idea what your averages where like for your commute before and after the new tyres? It'd be nice to have some figures on it as I'm planning to go from the Nimbus Armadillos to those tyres for exactly the same reasons.

My best time home from work is a little over 54 minutes (~17.5 miles). That was on GP4000S'es which are race-style tyres. Now I have mudguards and Marathon Plus tyres I'm coming in at around 1h15, sometimes more!

Probably most of this is seasonal and the tyre change is coincidental but I think the fact that you 'feel' the tyre weight a lot more, mentally drains you!

I purchased a new Giant Hybrid Cycle in April this year. Giant fit 'Maxim Overdrive' 700 x 35c tyres which previously I admit I'd never heard of. I regularly commute to work each day and do on average 40 miles a week in all weathers and a mixture of Road and Cycle paths. One cycle path goes through the middle of a Council estate where some 'miscreants' think it amusing to add broken glass to the surface. Touch wood, I have had no punctures and extremely impressed by these tyres.!
I have to add that I've learnt that keeping the pressures right up to a maximum is a good way of stopping foreign bodies getting into your tyres.
Previous to this on my older bike I used a mixture of Slime inner tubes with Panaracer 'puncture resistent' tyres and suffered a few punctures until I invested in a decent floor pump and kept the pressures right up.
When my Maxim Overdrive tyres start to show signs of wear I will probably replace them with the renowned Schwalbe Marathon Plus. Albeit these are slightly heavier but for peace of mind when riding in all weathers and all times of the day, would be worth it.

There's an interesting test of tyres with puncture protection in Cycling Plus.
They reckon the Conti Top Contact - 2nd only to the Marthon Plus for toughness but less than half the weight and rolls much better.
Not tried them myself, but might do.

EdinburghFixed wrote:
It sounds like you need a bigger chainring, as even Sheldon Brown doesn't list 10-tooth sprockets!

If you leave the small ring alone, you'll still retain your existing climbing ability.

Yeh you have a point... my rationale was that the front derailleur only just works perfectly now, and having an even bigger size difference between rings would probably make it annoying again. Plus by changing only the little sprocket I would only change one gear rather than messing with all the ratios (which strangely is what I want, although there is a good argument for changing all ratios). finally I have two sets of wheels, the other set has big nobbly tyres for off road use, so it is advantageous to have my gearing adjusted through the rear hub rather than front chainrings.

As it happens though I seem to run out of gears pretty much at peak power output (i.e can't go any faster down hill), so until I gain some fitness I don't think I am being limited. I also seem to have gear ranges that match the hills of my commute better, previously I was often between middle and big ring, but now the big ring isn't quite so big things are "just right".

Anyone know how successful changing just one chainring is? Does it usually cockup the gear shifting? Even allowing for correct capacity in the front derailleur.

minkie wrote:There's an interesting test of tyres with puncture protection in Cycling Plus.
They reckon the Conti Top Contact - 2nd only to the Marthon Plus for toughness but less than half the weight and rolls much better.
Not tried them myself, but might do.

I question the scientific basis of those puncture tests.. Some seem to involve a blunt screwdriver, some weights and some vibration + time. Not really representative of real life glass shards.

It might not be quite so scientifically repeatable, but why not ride over real life things like broken glass, flint, metal things, different tyre pressures, etc? Do enough of this testing and it will iron out any discrepancies in the individual test runs.