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Muppets Threads! (And Anything Else) / Re: The Return of Global Warming?
« Last post by julk on Today at 04:46:40 PM »
John,
that looks like a nice scythe, but I would plump for one with a wooden snath.

I got the one I use from https://www.thescytheshop.co.uk/index.html plus a shorter one for my wife,
and a selection of blades for use with length in inverse proportion to what is being scythed.
Julian
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Thorn General / Re: New to me Raven Tour
« Last post by mickeg on Today at 01:56:15 PM »
Quote from: Andyb1 on Today at 11:54:59 AM
...
So what are the advantages of presta on wide rimmed bikes with low pressure (~50psi) tyres?
...

Wide tires with low pressure, Presta is not much of an advantage. 

In my case it goes back several decades, I was riding narrower high pressure tires with Schrader valves and often lost several PSI when I took the chuck off the tire.  And I often lost several PSI when using a gauge to check pressure.  So, when I started to buy Presta, I totally stopped buying anything Schrader.

But with lower pressure and wider tires, any pressure loss when you take the chuck off will be minimized.

Gauges, I have a Presta gauge, but almost never use it.  The pumps I tour with have built in gauges.  Those gauges are not very good, probably are plus or minus 5 PSI, but that is good enough for me.

If you are happiest with Schrader, I see no reason to change.  You explained why you wanted to make the change to Schrader.  And if you had Presta only pump that could not be converted to Shrader when you could only buy a Shrader tube, I can see that as a big reason. 

I carry pumps that can be converted.  Exception, I use a Presta only pump on my rando bike and road bike, but those bikes stay in places where I can buy Presta.  And those bikes have rims that are Presta only.  That said, I still have a Schrader adapter on each of those bikes, just in case I needed to use a car pump.

I will admit that when I am filling up a 57mm wide tire at home, I am inclined to use the Schrader adapter on my Presta so that I can use an electric pump.

I use tires as narrow as 40mm on my Sherpa, 37mm on my light touring (titanium) bike, so I do pump those up to higher pressures when touring.
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Thorn General / Re: New to me Raven Tour
« Last post by Andyb1 on Today at 11:54:59 AM »
The old presta vs schrader debate!
I used to have everything presta but after getting stuck a few years ago when my bike pump broke and I could not pump up my repaired presta valved innertube (but I could have borrowed a car pump) I started to go to schrader, but it is taking years to make the change over!  Consequently I still use some presta valved innertubes and carry adaptors to screw on the top to go to schrader.

Advantages of schrader to me are:
- always a car pump around!
- when I damaged my schrader hand pump in India I bought a good alternative for £5 - no presta pumps available
- with lower tyre pressures / wider rims schrader work fine (maybe not so good for high pressure / narrow or deep aero type rims, but I don’t use those).
- my pressure gauges are all schrader ones
- valve stems stronger - I have bent the screw ends of presta valves in the past - and last year in cold weather I miss-fitted a long stemmed presta valve which blew the next day as it was not fully pushed through the rim due to jamming on the pastic schrader / presta hole adaptor.
- schrader valve inserts easily changeable at car garages if required.
- presta valves can undo a little and give a leak
So what are the advantages of presta on wide rimmed bikes with low pressure (~50psi) tyres?

Tyres.  I want to use up the tyres I have so will probably run on a 2.0 dureme front / 1.75 marathon plus at the moment and go from there.  Thanks for the recommendations Martin, I will come back to those options in due course.

I weighed my sherpa and raven many times yesterday as I swopped parts across like the saddle, pedals etc and the raven was about 0.5kg heavier once different tyre weights were accounted for.  The sherpa is now set up as a rather nice looking flat barred bike with rear rack and shiny stem weighing in at 13.0kg. Unfortunately it will have to go once I get a few miles on the raven to make sure all is good.
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Thorn General / Re: New to me Raven Tour
« Last post by martinf on Today at 07:02:02 AM »
Quote from: Andyb1 on July 14, 2025, 10:09:07 AM
and a dureme tyre replaces the front Marathon.

I'd also replace the rear tyre with a kevlar bead Mondial at 675g in the 50x559 size. This should save a fair bit of weight over a Marathon Plus and work better if you use rocky tracks. The wire bead version of the Mondial is cheaper, but heavier at 740g. And not quite so good for sidewall protection and puncture resistance.

Or, if you will be on tarmac most of the time, put the Dureme on the back and a light tyre on the front, for example :

https://www.bike24.com/p2360101.html

I use the Continental Contact Urban on my Bromptons, it has reasonably good puncture resistance and low rolling resistance. Also fairly light at 590g and relatively inexpensive. The 47-559 version is slightly lighter at 560g.
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Thorn General / Re: New to me Raven Tour
« Last post by mickeg on Today at 12:45:03 AM »
Quote from: Andyb1 on July 13, 2025, 08:20:41 PM
...   Change presta innertubes to Schrader……
...

I have been thinking about this, why would you want to do that.  I can see making sure your rims are drilled to Schrader size hole in case that is the only tube you can buy, I drilled the rims on my Nomad Mk II for that reason.

But I still want Presta on everything that does not have a motor in it.

I have a Schrader to Presta adapter threaded on one wheel on each of my bikes, just in case I might want it some day.  And a Schrader valve cover over the top of that adapter.

I used to use the metal Presta Savers, but had corrosion problems.
https://www.sjscycles.co.uk/rims-tape/wheels-manufacturing-presta-tube-stem-saver-fits-schrader-rims/

Now use the plastic ones.
https://www.sjscycles.co.uk/rims-tape/mavic-rim-valve-hole-drilling-converter-insert-schraeder-to-presta/

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Muppets Threads! (And Anything Else) / Re: The Return of Global Warming?
« Last post by Andre Jute on July 14, 2025, 11:42:19 AM »
Your friend is making a joke with you, Matt. All the possibilities of any event occurring will fall between 1 and zero, the same as a shrug or 'Who knows?' And, to confuse the matter further, when we're talking about natural occurrences on geological scale, with only two or three possible outcomes stated (ice age, warm age, interglacial transition), I'm willing to make a case that, absent historical knowledge, in practice the likelihood of zero and evens (0.5) are actually the same. But we do have historical knowledge from core samples that ice ages are much longer than warm ages, and that in the last two millennia there was a flux in between centuries-long cold and warm periods, so the likelihood of natural occurrence in any reasonable period, say a handful of centuries, is actually positive, that is, above 0.5.

I take the view that perfect certainty is a delusion of the academic classes and dishonest bureaucrats.

Sophisticated people with their own money at stake are usually willing to make serious decisions at 0.05 uncertainty, which is the same as 95 percent level of confidence (an expensive place to arrive at because statistical confidence is dependent on the size of the sample interrogated) when the due diligence is correctly done with 'known unknowns' (Donald Rumsfeld?) given a suitable value and the 'unknowable unknowns' (ditto) are given a conservative discount.

John, coincidence is the stretch between 0.95 and 1.00, otherwise known as what screws the best laid plans of Man aka Arrogance. There's no sure thing when Murphy is around.
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Thorn General / Re: New to me Raven Tour
« Last post by Andyb1 on July 14, 2025, 10:09:07 AM »
Those Salmon Koolstop pads sound good, but I want to use up the ones I have before buying more!   SJS can supply which is convenient for me as I can ride there.

The instructions I can find for the Avids is to set the pull ratio half way and then adjust either way from there.  I expected one extreme for V brakes and the other for cantis.

The adjustment is easy to change and on a ride I was able to tweak the settings so the brakes work the same.

Bike now built up with some parts from my Sherpa eg Thorn touring handlebars.  As in the photo with empty luggage it is 18.2kg and this should reduce to 18.0kg once the bar ends go and a dureme tyre replaces the front Marathon.
The brooks saddle and pedal change added weight!

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Thorn General / Re: New to me Raven Tour
« Last post by mickeg on July 14, 2025, 09:13:39 AM »
I agree with PH, the Salmon Koolstop pads are what you want.  Dan on this forum has also suggested that your rims may last longer with the Salmon pads.

When I change the oil on my Rohloff, the hub is fairly quiet in gear 7, but gets much noisier as more oil leaks out.  Gear 7 is supposed to be noisy.  I have only used my Rohloff that I bought in 2013, have nothing else to compare to.

If you have V brakes but the levers are set for a short pull like road brake levers, you have more leverage on the brakes and that can be a bit too good, as you could go over the handlebars if doing an emergency braking.  I have mini-V brakes and road levers on my Airnimal, I have to be careful to not pull too hard on my front brake lever.
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Thorn General / Re: New to me Raven Tour
« Last post by Andyb1 on July 14, 2025, 08:32:46 AM »
Thanks PH - I probably need to tweak the ‘Speed Dial’ knob on the levers…..Strange they call it SPEED dial when it is a brake…..as you say, it changes the pull ratio of the lever.
Rohloff noise - glad to hear it is normal on older hubs.

I will weigh my Sherpa today to get a comparison with the Raven.
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Thorn General / Re: New to me Raven Tour
« Last post by PH on July 13, 2025, 10:23:07 PM »
That looks tidy, black and silver is always classy.
Quote from: Andyb1 on July 13, 2025, 08:20:41 PM
All working OK but noisy in 5 and 7.  I am used to a 2023 Rohloff on a different bike - were earlier hubs noisier? 
There's some variation between hubs even with close serial numbers, but generally I think earlier hubs were a good bit noisier.  The good news is they're also better sealed, Rohloff changed the design to increase efficiency at the cost of sealing, IMO it wasn't a great trade off. I hardly notice the difference, but my original hub was submersible! And despite the miles, also the noisiest.
Best V brake blocks I've tried are Koolstop Salmon, with BBB TriStop not far behind and a bit cheaper.  Both of those are also kinder to rims than most.
If you were not aware - Some Avid levers had settings for both Canti and V brakes, I've forgotten how you set them up.  But if you use V brakes on the canti setting, you get a very firm feel, but poor braking.
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