What's your Rohloff combo (chainring, cog)?

[martinf]

Got the answer for the first of my 3 questions about chainglider use.

1 - Are there are any performance reductions?

As far as I'm concerned, no.

Four 25 km rides over a moderately hilly, mainly rural, local route before fitting the chainglider, average speed 24.00 kph, another four 25 km rides over the same route with the chainglider 23,99 kph.

Slowest of the 8 runs 23.39, fastest 24.42 kph.

Total climbing for the 24 km circuit 210 metres, obviously the same amount of downhill.

The chainglider must make a tiny difference due to the extra 300 grams or so, but any friction generated by the thing riding over the moving chain seems to be fairly negligible, even with my imperfect setup.

I think the faint "swishing" noise, which I believe is the slightly too thick chainwheel rubbing in the front bit of the chainglider, has got quieter, but it might just be that I've got used to it.

[Andre Jute]

Got the answer for the first of my 3 questions about chainglider use.

1 - Are there are any performance reductions?

As far as I'm concerned, no.

Four 25 km rides over a moderately hilly, mainly rural, local route before fitting the chainglider, average speed 24.00 kph, another four 25 km rides over the same route with the chainglider 23,99 kph.

Slowest of the 8 runs 23.39, fastest 24.42 kph.

Total climbing for the 24 km circuit 210 metres, obviously the same amount of downhill.

The chainglider must make a tiny difference due to the extra 300 grams or so, but any friction generated by the thing riding over the moving chain seems to be fairly negligible, even with my imperfect setup.

I think the faint "swishing" noise, which I believe is the slightly too thick chainwheel rubbing in the front bit of the chainglider, has got quieter, but it might just be that I've got used to it.

That's a very fair report, Martin. Statistically, your rides are so well within the margin of error that we would have to say there is no performance degradation. I notice the "roadie caveat" about the influence of 300 grams, and grin, but in a 100kg or thereabouts all-up package the difference would be swamped in what you had for breakfast, and the time differential accounted for by an imperceptible change in wind speed or direction.

***

It will be interesting to see at which point interior wear from a chainring/chain outwith the recommended parameters becomes visible, and whether it continues  to wear, or settles when the Chainglider is worn just enough to give the unsuitable components operating space. Possibly that could be the point where it becomes totally silent. The Germans are notorious for overbuilding their components (not just bicycle gear) and then underspecifying it for public consumption: there's always a large margin built-in.

So I think it likely that in time we will discover that:

1. For marginally out of spec chainrings and chains no damage inside the Chainglider will ever be visible.

2. For any operable (but more than marginally larger than recommended) width of chain the internal marking of the Chainglider will stop when an accommodation is reached. Otherwise we would long since have heard of Chaingliders worn through in a few thousand kilometres, and we haven't.

3. A chain that is really too wide will be sticky inside the Chainglider and the drag will cause it to be removed. Speculation, of course, until some rich poster sacrifices a really thick chainring and Chainglider in the interests of bicycling science (could be a knighthood in it though...).

***

Congratulations on a thorough test, Martin.

I especially liked your test course, as one of my favourite rides is 22km with, you guessed it, 210m of climbing.

Andre Jute

[martinf]

Got the answer for the third of my 3 questions about chainglider use.

3 - Does it work or not to reduce chain maintenance/increase transmission life?

I did my test ride in the dunes today, 67 kms in all including the ride there and back, plus the sandy tracks, wet today because there were heavy showers. In a few places the sand was too soft to ride on, so I pushed, in these areas the wheels sank in about 5 cms.

After a few hundred metres in wet sand the chain would normally be grating, so I reckon the chainglider protects the chain quite well. In the photo of the chainglider you can see some of the sand that would otherwise have gone on the chain, but the rain has washed most of it off.

When I got back home I opened the chainglider. There was a small amount of water inside but I didn't find any sand. I did find some greyish paste near the chainring. After I cleaned that off and put the chainglider back together it seemed to rub even less than it did before.

So I'm satisfied that the chainglider is going to save me a significant amount of chain cleaning time and very probably increase chain/sprocket/chainring life.

[Danneaux]

Martin!

I salute your efforts and testing methodology, and thank you for being kind enough to share the results with all of us.

Really well done!

(Loving the photos and bike, too)

All the best,

Dan.

[rualexander]

On the subject of the Chainglider, how much dismantling is necessary to take the rear wheel out in the event of punctures, does the whole Chainglider have to come off or just the rear section?

[il padrone]

Martin, off the topic a bit, but what are the covers on your front wheel spokes?

[Danneaux]

...what are the covers on your front wheel spokes?

Hi Pete,

I can't answer for Martin, but they look a lot like something I've been looking at:
http://www.rei.com/product/808967/lightweights-for-wheels-power-reflectors
Company home page here: http://www.lightweights.org/store/product.php?productid=1
"Lightweights for Wheels Power Reflectors", little tapes of stick-on 3M Scotchlite that roll onto the spokes and make the wheels reflective. Same basic idea as the Reflex tape on Schwalbe tires, but for the spokes.

Best,

Dan. ("best guess")

[martinf]

Martin, off the topic a bit, but what are the covers on your front wheel spokes?

http://www.acelo-shop.com/16099832.html


SekuClip spoke reflectors made by 3M. Got my first packet direct from Germany, but now my local bike shop stocks them. I think they are more effective than reflective bands on tyres and the traditional type of flat reflector. Being cylindrical in shape, they are visible from more angles. Also fairly light and don't unbalance the wheel.

Didn't put them on the back wheel as oil from the chain and my Sturmey hub quickly dulls out reflectors. I might try now I have the chainglider. On the front wheel they still pick up grey mess from the rim brakes, but generally stay cleaner than reflective bands on tyres.

For butted spokes on another bike I had to use a bit of insulating tape round each spoke to increase the diameter so that the SekuClips would hold.

[martinf]

On the subject of the Chainglider, how much dismantling is necessary to take the rear wheel out in the event of punctures, does the whole Chainglider have to come off or just the rear section?

Theoretically just the rear section, which is in two parts. I had it apart yesterday to check the inside, the whole thing comes apart very quickly indeed, it takes a little longer to put back together and it is a good idea to memorise the adjustment before dismantling - i.e. how many ribs are visible top and bottom at the join between front and rear parts.

I don't consider it an issue, for one thing it doesn't add much time, and anyway punctures are very rare with the Marathon tyres I have on that bike and the Supremes/Duremes I intend to run on my future Nomad. The chainglider might even make things easier, as I suspect there will be less oily mess around the rear wheel.

Incidentally, I often don't bother removing the wheel to fix rear punctures on hub gear bikes - if the weather is dry and not too cold I get the tyre off the left side of the rim and pull enough of the tube out to patch it in situ rather than replacing the tube and patching later.

[Andre Jute]

it is a good idea to memorise the adjustment before dismantling - i.e. how many ribs are visible top and bottom at the join between front and rear parts.

Since I ride on banded tires, I've only had the rear wheel out perhaps once a year, for the bike's spring clean, and memorizing the adjustment didn't occur to me. The usual adjustment, if you get the initial fit wrong by feel of how tight the rear part of the Chainglider slots in against the sprocket teeth, is usually just one click outward, either top or bottom, so a 50/50 chance of getting it right first time. So I fit the Chainglider, wheel the bike a pace backwards and forwards, and if there is the slightest noise, I make an adjustment, wheel it again, and make the other adjustment if necessary. That's it. (I don't ride the bike for this test because the roads here are rough enough for tyre noise to drown out the noise of a maladjusted Chainglider: even maladjusted, the thing makes very little noise indeed. But the patio in front of the stables, and the sidewalk in front of my town house, where I tend drop the wheel, are both smooth enough for this test.)

But for those of you who still ride on unbanded or inadequately banded or vulnerable soft sidewall tyres, Martin's idea of remembering the adjustment by the number of lockribs showing is excellent. Also works by feel in pitch dark for the tourers.

Andre Jute

[il padrone]

My Chainglider arrived on Friday. I fitted it yesterday and took it on a 69km ride through the hills today. It only lasted 10kms  

I made a discovery - the Chainglider does not like running with a Thorn reversible chainring. I thought it might be OK, gave it a go, but by the time I was climbing the first steep hill, and everyone was leaving me behind it was obvious that the swooshing noise really was increasing my pedaling drag  . The black chainring has a nice silver rim about it now. I took the Chainglider off and rode the rest of the ride much more easily.

I shall have to buy myself a narrower chainring (maybe a stainless one rather than alloy) and swap it on. Thing is this would make the most sense when the chain has worn out and I can fit a new chain with the new chainring. This chain is on the way out - done about 3500km. But it is one of three I am rotating, so between the three it could be another 2-3 years or more before I really need the new chain  

Anyway, be aware, Thorn reversible chainrings do not work with the Chainglider, they are just too thick.

[Andre Jute]

Anyway, be aware, Thorn reversible chainrings do not work with the Chainglider, they are just too thick.

Now we're establishing parameters! Anyone know how thick the Thorn reversible chainring is?

Hebie's spec for the Chainglider: max chainring thickness, 3mm; max chain width, 9mm.

The Surly stainless chainring, also reversible, is 2.6mm by my measurement. It works fine with the Chainglider. SJS stocks it 5-arm  110mm BCD suitable in 38/40/42 tooth:
http://www.sjscycles.co.uk/surly-110-pcd-5-arm-stainless-steel-chainring-38t-silver-prod20828/
http://www.sjscycles.co.uk/surly-110-pcd-5-arm-stainless-steel-chainring-40t-silver-prod27315/
http://www.sjscycles.co.uk/surly-110-pcd-5-arm-stainless-steel-chainring-42t-silver-prod19787/

Andre Jute

PS Sorry about your scuffed chainring, Pete. It never occurred to me that the Chainglider would mark it until I saw Dan's post below. I expected the Chainglider to be marked by the metal, instead.

[Danneaux]

When I inquired about the Chainglder, Robin advised using the Surly stainless chainring with it; others were simply too thick to work well.

My thinking was if the Chainglider cleared a chain...it must surely clear a chainring, which is narrower. The cover must somehow snuggle in around the chain for a close fit at the 'ring?

Never thought it might result in a scuffed finish on the 'ring...I just thought it might be a little noisy, and that would soon clear with use.

'Wish I had thought to warn Pete, but he had already placed his order and I didn't think to check what chainring he was using, else I surely would have sent him a note before he tried it.   Sorry, Pete.

Best,

Dan.

[martinf]

It never occurred to me that the Chainglider would mark it until I saw Dan's post below. I expected the Chainglider to be marked by the metal, instead.

I think the small amount of grey paste I cleaned off the area of the chainglider near the chainring the other day is a mix of aluminium off the chainring and plastic off the chainglider - rather like the muck formed by rim brakes.

Didn't notice any wear marks on my chainring, but it was already rather weathered before I fitted the chainglider and I didn't examine it particularly closely.

Unlike Pete, I haven't noticed any slowing effect, maybe its the black anodising or maybe the Thorn ring is just thicker than my TA ring.

It would seem that chainring choice is fairly critical for a chainglider to work well.

To get back on topic, instead of my original 50/21 choice I will now go for a 38T chainglider-compatible Surly steel ring and 16T sprocket on my future Thorn Nomad.

I maintain several other hub-gear bikes. The chainglider isn't compatible with the family Bromptons, nor with two of the large-wheel bikes. There is a tensioner on my 8-speed and there isn't a chainglider version for the 32T chainring/22T sprocket on my wife's 5-speed.

But the two visitor bikes at our island flat have 38T/22T so should be compatible. These are already as "low maintenance" as I could get them to be, with 3-speed gears, drum brakes and Marathon Plus tyres, so chaingliders would be a logical addition, with the added benefit of protecting visitor's clothing from chain oil (not really a factor for my own cycling use).

[E-wan]

I run 50x17 on my nomad with 165mm cranks

find it fine most of the time, can clime most things on the road I would want to with a moderate load peadiling up 16% gradient or so.

if towing my child trailer the its fine on steep hills unless I try and carry more than 1 pannier as well, then I would probably want something lower.

If I go of road this gearing is to high.

I also have a 40T ring but have never swapped to it yet.  I am running a SRAM chain and would intend to use  a couple of power links to make it easier to swap for a lower gear if necessary if I wanted to.


I often find myself in 13-14 with this gear combination on the road and if going downhill could make use of 2-3 higher gears.