Does the efficiency, or noise, of a chainglider vary with chain tension? It's hard to imagine how it wouldn't and my experience with a Rohloff, and other hub gears, is that they run noticeably smoother with a slack chain.
I want a rohloff , chain and chainglider
But I’m totally bamboozled by the rear sprockets and chainrings
Does the chainglider only fit certain combinations and Certain brands?
Is there like a standard universal combination that is tried and tested that would be a good recommendation?
Does the chainglider only fit certain combinations and Certain brands?Yes, I'll second what Andre said and and home in on one more caveat:
...In practice all that is required is for the bike builder or assembler to measure from the centre of the pedal axle to the centre of the rear axle, and to order the long or the short front part of the Chainglider accordingly......With the eccentric (on a Thorn) in the full-forward position to make sure of the maximum reach needed.
Thanks Andre, I'm going to have to file this one away in the box labelled things I don't understand.Does the efficiency, or noise, of a chainglider vary with chain tension? It's hard to imagine how it wouldn't and my experience with a Rohloff, and other hub gears, is that they run noticeably smoother with a slack chain.
The short answer is no to both your question and your further perfectly logical supposition.
Thanks Andre, I'm going to have to file this one away in the box labelled things I don't understand.Does the efficiency, or noise, of a chainglider vary with chain tension? It's hard to imagine how it wouldn't and my experience with a Rohloff, and other hub gears, is that they run noticeably smoother with a slack chain.
The short answer is no to both your question and your further perfectly logical supposition.
I had hoped that as I got older I'd start emptying it, but it just looks like I'll need a bigger box.
QuoteDoes the chainglider only fit certain combinations and Certain brands?Yes, I'll second what Andre said and and home in on one more caveat:
Choose your crankset's BCD/PCD (bolt circle) carefully when you order your bike. I am running a Deore crankset with 104mm BCD. Unfortunately, Surly stainless chainrings are not available in tooth sizes larger than 36t in a 104mm BCD and I am running a 36x17 combo. As was recently mentioned here, suitably thin steel BMX chainrings are available in larger sizes but tend to run toward non-stainless.
Needless to say I want a Chainglider too, but so far have been out of luck unless I change both bottom bracket (an expensive Phil Wood unit), chainring, crankset and sprocket to something closely equivalent to the ratio I have that will fit the Chainglider. Hebie might introduce additional sizes in the future. Alternatively, Surly may expand its range of 104mm BCD chainring sizes. I hope so. That way I would only have to buy a new sprocket and chainring to fit one of the existing Chainglider sizes/front-rear combinations.
Best,
Dan.
How’s this one?That crankset is probably OK and would work with a Shimano UN55 bottom bracket cartridge. However, the UN55 has been discontinued but I believe that SJS has found a substitute. Once you have decided on your preferred crank length and BCD / PCD (to suit your choice of sprockets) then Thorn / SJS can recommend suitable crank / bottom bracket combinations.
https://www.sjscycles.co.uk/cranks/sjsc-110-pcd-alloy-singledouble-crankset-170mm/
If that is okay , then what about a bottom bracket? I’m clueless
Just to clarify , are you saying the Thorn chainring you linked will or will not be compatible with the chainglider?The Thorn chainring will not work with the chainglider as it's too thick. I was just trying to point out that it's thinner where the teeth are. The chainglider encloses the chainring about 1.5cm in from the end of the teeth where the Thorn chainring is its full thickness.
I from heard from Thorn today that they have no 26” forks left for nomad mk3 builds until March 2022 !!
so looks like my only choice is a mk2 in 620M or 620L
I do “just” fit into the height measurement for this frame which Thorn says is the equivalent of a 21” mountain bike frame.
So hmmm 🤔 need to ponder this one
EDIT: I see the surly chainring is 110mm, does that mean the bottom bracket has to be 110mm ?No. The bottom bracket number is (I think) the axle length whereas the chainring is interested in the diameter of the circle for the bolts fixing the chainring to the cranks. Thorn use a square taper bottom bracket. This type means the crank axle has slightly tapered square ends onto which the cranks are fixed by nuts. Different square taper cranks would fit 110 (or 130) BCD / PCD cranks. There's a place called SourceBMX which sells 104BCD steel chainrings. I'm using one of those so I could fit a chainglider on my Mercury which has the same 104BCD cranks.
I from heard from Thorn today that they have no 26” forks left for nomad mk3 builds until March 2022 !!
so looks like my only choice is a mk2 in 620M or 620L
I do “just” fit into the height measurement for this frame which Thorn says is the equivalent of a 21” mountain bike frame.
So hmmm 🤔 need to ponder this one
What is your time frame?
Less than a year to wait.
I love a good countdown.
More time to save up for extra goodies. And there will be lots.
The anticipation. Expectation. Marking those weeks and months off on the calendar.
Don't compromise. Get it right first time.
I've put a short article in the Rohloff forum to relate all the components in the transmission of the bike near the bottom bracket together spatially, because it causes novices, and some old hands too, considerable confusion:
Specifying the BB axle length WRT the Rohloff HGB chainline (http://thorncyclesforum.co.uk/index.php?topic=14144.0)
Sadly, the Chainglider didn't work out for me due to incompatible chainring.I bought a chainglider-compatible chainring from https://www.sourcebmx.com/products/jet-bmx-4-bolt-race-chainring.
Details please, John.Which John?