FBinNY 

So don't.

The right chain lube can easily survive multiple wet rides and protect your chain from the effects of road spray, without meaningful effort from you. (not naming names here).

martianone

My commuter is a 1x9, road bike 1x10, city bike Nexus 8 spd - seems like bike geometry, fit, tires, riding position, bike weight, tires, drive train set up and cleanliness, etc., effect speed more than the supposed 2-3 % loss due to IGH. My road bike is the fastest; the fit is optimized for speed, wheels & bearings smooth, aero wheels and tires - so I would anticipate it being faster than the city bike.

CrankyOne

One of the great the great things about IGH is that you can enclose your entire drive system in a case. You may need to open it up and clean and oil it every 10 or so years though.

Gresp15C

Riding that route with a S-A hub, someday, is on my bucket list. Maybe in 2029.

Dahon.Steve

The Wikipedia article was biased and had an agenda. It appears the forum members accepted Chester Kyle’s 2% loss in friction as gospel without noticing the study was flawed.

First, the study failed to mention the loss of energy due to the coaster brake fixed to many internal hubs. They conveniently left this out because friction losses would probably bring efficiency losses past 5% or more! I even sold my brand new (Bianchi Milano) because the 7 speed roller brake scrubbed off so much speed leaving me exhausted. I replaced that bike with a 20 year old Univega hybrid with an 8 speed cassette because it was far more efficient.

The Wikipedia article even lists the coaster brake as an advantage! How can it be advantage if it slows the bike down? The Sram Spectro 3 (coaster brake edition) was notorious for making the rear wheel come to a complete stop in 30 seconds or less after spinning it by hand.

Second, the study was done in room temperature and not in cold weather. Anyone who uses internal hubs knows you’re going to experience friction losses when the temperature drops below 30F degrees. Once the oil or grease start to freeze, friction losses are much higher than 2%.

Third, the Wikipedia article states hub gears can be used for mountain biking. There is only one internal hub that can be used for mountain biking. All others have been destroyed on the trails.

Fourth, the study did not mention the energy that must be used to rotate the heavy internal hub from a full stop. Since his mechanical contraption was only able to determine friction losses within the hub, it could not measure the human element in this equation.. Yet for some reason, everyone who rides a hub gear bike (7 or more gears) complains about the weight in the rear wheel?

______________________________
One other point should be made. While propelling, a part of the rider's energy is consumed by the clutch's designed-in friction. Even though the wheel might be able to spin an entire minute with the bike upside down and hand cranked, the propelling state consumes energy overcoming the clutch's intended friction. It's not much, and it's tiny with respect to wind resistance (and maybe even tire resistance), but it's there. If there's one design flaw in a coaster brake, this is it.

Overhauling a Coaster Brake Bike

dunelt_1954

On the sort of bicycle that one usually finds an IGH, the hub is not the limiting factor. My admittedly limited IGH experience is with S/A 3 speed hubs, both old and new, and a J.C. Higgins with an Austrian clone. The latter was my intro to the joy of internal gears. Anyway, my present commuter is a 1974 Columbia Sports 3. Heavy, yet kind of flexy. I like the ride from the long seat stays and mild steel, though. But, the frame probably sucks up more energy than the SunRace SRF-3 hub. And, it is running Schwalbe Marathion Plus tires in 42-590. Heavy! But, with Chain-L on the chain, a wipe down when getting the salt off the wheels and underpinnings is all that is needed. I did flush the hub and converted to ATF from the factory grease at about 2 years and 2500 miles. At that point, I replaced my 20 tooth cog with a 23, and replaced the chain as well. This seems like pretty low maintenance to me. And, what the bike looses in speed, I save in time not flossing gears, adjusting derailleurs, etc.

There are varying degrees of losses in derailleur systems, depending on the size of the gears. Probably cross chaining, small ring to a small cog, is the worst possible efficiency. But, whether you slept well, had your second cup of coffee, etc. all will relate to speed more than the sort of drivetrain, given similar bike geometries, tires and other variables.

GovernorSilver

This is consistent with what I hear from bike shop folks whenever I ask them about what to do after my bike gets wet. Everybody says water won't hurt your bike.

They also say cyclists tend to put too much lube on the chain.

Salt that was used to melt ice though could be a problem, but they say a quick rinse from a hose (light water pressure) will take care of that.

FBinNY 

[QUOTE=Dahon.Steve;18622021]The Wikipedia article was biased and had an agenda. It appears the forum members accepted Chester Kyle’s 2% loss in friction as gospel without noticing the study was flawed.......

______________________________
One other point should be made. While propelling, a part of the rider's energy is consumed by the clutch's designed-in friction. Even though the wheel might be able to spin an entire minute with the bike upside down and hand cranked, the propelling state consumes energy overcoming the clutch's intended friction. It's not much, and it's tiny with respect to wind resistance (and maybe even tire resistance), but it's there. If there's one design flaw in a coaster brake, this is it.

Whenever someone opens a post saying others have a bias and agenda, I start wondering about theirs.

It's pretty obvious that you're not an IGH or coaster brake fan, which is fine, but there's no need to exaggerate issues to push an agenda.

The last reference to coaster brake clutch drag is an example. It's infinitesimal, in the range of the seal drag on modern BBs and hubs, so nothing to even consider. It's certainly far less than the losses to the gear train which is already accounted for. Clutch drag is also a fixed constant, rather than a percentage of power, so as load increases it's impact lessens.

Nobody claims that IGH and coaster brake are as efficient as direct drive single speed or derailleur. Those who fret over clutch drag might also worry about the added drag imposed by the pulleys and spring chain tension. (both also meaningless).

kickstart

If those things were really a problem, we here in the Pacific Northwet would be in serious trouble.

GovernorSilver

The salt or the water?

tjspiel

I've had lots of problems with rust on chains due to salt. Rinsing it off from a hose is probably a reasonable solution if you live somewhere where temps poke above freezing on a regular basis during the winter. Where I live in in a normal winter it can go several weeks without getting that warm. I shut the outside water off in November and I probably won't turn it back on for a couple of weeks yet.

I won't be rinsing off my chain very much in January.

Plus, sometimes I think the bike shop guys give advice with the assumption that you're riding on weekends and not every day. Do you really want to have to rinse your chain off every day?

I do use rust resistant chains and in a mild winter like this past one, they hold up OK. However, with all the sand that gets put on the roads along with the salt they still end up with a lot of grit in them, even with fenders. They tend not to last long.

A belt drive has a lot of appeal for me.

Rain isn't a problem. I think you have more problems with rust if you ride infrequently and then leave your bike sit for days or weeks after getting wet. As long as your riding regularly and running through the gears, everything stays lubricated enough to keep rust at bay.

tjspiel

Some IGH's have a direct drive gear, others don't. I'm not sure if the 2% figure is some sort of average or what that translates to in real world use.

I have a fixed gear, and IGH, and a derailleur bike. I use the bike with the IGH in the winter for the simple reason that the mechanicals are not exposed to the elements like derailleurs are. Shifting while stopped and silent coasting are other nice things. That said, I'm not at all inclined to use an IGH on my "fast" bike. The quick shifting and closely spaced gearing of a high quality and well tuned derailleur system is pretty sweet. I also prefer light to heavy, unless the extra weight comes with an added value that matters to me.

The choice between one or the other would make little difference for most people's commute times, so I wouldn't go with a derailleur in hopes of getting to work faster.

GovernorSilver

Yes, here in this area, temperatures frequently poke above freezing during winter. You would be right in assuming that the bike shop people (yes women work at bike shops here, maybe not in your state) dispense advice appropriate to the climate in this region. Your assumption that not a single bike shop employee in this region knows how to advise commuters vs. weekend riders, however, is not quite fair. Come down here and meet commuting riders, talk to them about the LBS's here and you'll know what I mean.

kickstart

Both, depending time of year.

GovernorSilver

Well the salt situation in DC is different than the Pacific Northwest. Here we encounter it only after it has been laid down on the roads after snowfall. Most bike commuters here do not live close to the ocean.

All your bikes have IGH? Does everyone ride with IGH in your region? Help me make the connections here.

bigbenaugust 

I have a Bakfiets with an 8sp S-A hub, and I am sufficiently enamored with it that I am thinking about getting an IGH wheel for my Fantom Cross Uno. But there aren't a lot available in a 120mm OLD to match the frame and I'm really not interested in spreading the frame as that would shorten the rear triangle.

kickstart

I have both IGH, and derailleur bikes, and use both for commuting. If I had to choose one, it would be my classic Gazelle as it requires virtually no maintenance regardless of conditions.

I see a wide variety of bikes being used by regular, year round commuters.

GovernorSilver

Ok I think I see what you mean. You guys and gals have no fear of salt or water for your bikes - and you had plainly stated that. For some reason I read your post incorrectly.

At the LBS where I bought my 2nd bike, the people were more concerned about grit getting into their components than water, because the neighborhood (College Park, MD) can be on the dusty side - combination of road conditions and dust/dirt/grit constantly being kicked up by cars and other thigns.

wphamilton

I am a little skeptical of 2% more drag of IGH. I think it may be true in some case but not in general, because if I'm not mistaken they generally have planetary gearing which have greater losses than that due to having multiple stages.

It may be true that at very high power outputs the power-dependent losses become larger in proportion to this kind of drag, which would make the efficiencies seem more similar at higher power, but the flip side is more percentage drag than that at normal rider power.

fietsbob

Throw them both off a bridge and see which one hits the water First.

tjspiel

I didn't say that not a single bike shop employee knows how to advise commuters. I said that "sometimes" bike shop guys (the generic guys) give advice more appropriate to recreational riders. I know of shops that have lots of commuting employees and customers and I know some that have virtually none.

GovernorSilver

You're right, you did say "sometimes".

But to be clear, no the LBS guys and gals who advised me on what to do with my web bike didn't say rinse off the chain.

They told me what parts to rinse off. I didn't feel it was necessary to spell it out - I thought you and other experienced cyclists already knew what parts could be rinsed off, whether with a light pressure hose, a wet rag, or whatever.

ijsbrand

As an all year round commuter, on both IGH and derailleur bikes, I have long ago come to the conclusion the weather and the traffic are both far bigger factors in travel time and/or effort than whatever makes up the drive train. So discussions about the efficiency of one tiny thing over another tiny thing are rather academic, and thus nice forum fillers.

tjspiel

I've actually considered bringing my bike into a car wash now and then during the winter and I *would* rinse off the chain (and then re-lube it). A wet chain is better than a salty one.

Really my point is that salt is highly corrosive and will do a number on your bike's bare steel components. Rinsing the salt off is a good idea, just not always practical.

FBinNY 

You're right to be skeptical of the "precise" 2% figure. However it's still a reasonable working rule of thumb. All bicycle drive train systems have 2 sources of inefficiency. All have some fixed parasitic drag from things like lube viscosity and unloaded movement, and there's load related drag which increases with load. The fixed losses factor more at low power, while the load related losses become more (relatively) significant at higher power levels. So any efficiency comparison will depend on the power level tested.

IGH hubs are tricky to rate for efficiency because it varies greatly by gear selection. Simple hubs, ie. 3s and 5s, use a single planetary stage and are most efficient in middle gear which is direct drive to the shell, so there's only the fixed parasitic drag. They're also pretty efficient in the higher gears because the loads tend to be at the lower end of the range. OTOH they can be more inefficient in low where the loads are higher. Muti-stage planetary systems are more inefficient because each stage adds it's own drag.

Derailleur systems have their own problems due to sprocket sizes, chain misalignment and power lost to the idler cage pulleys and lower loop tension. So any comparison can only be a rule of thumb guideline and as such the added 2% estimate is reasonable, but should not be taken as gospel.

In any case, efficiency is only one factor in the choice, with needed gear range, weather/riding considerations, purpose, weight, etc being others.

IMO- IGH shines for utility where the needed gear range is narrower, but is a poor choice when gear range, weight, and efficiency become more important. If anyone making IGH hubs were to ask me, I'd suggest focusing on simpler lighter 3 and 5s hubs of varying ranges, especially narrower ones to offer urban riders closer spaced gear choices for relatively flat terrain. They shouldn't chase the wide range multi-step market where they'll always be at a disadvantage to derailleurs.

FWIW- I own both derailleur and IGH, along with fixed wheel bikes (including a 2s fixed) and my choice depends on the application. What I'm still looking for is narrower 3s (or 5s) IGH suited to gently rolling (and varying wind) riding for utility and commuting. Sadly the IGH makers still don't realize (or feel they cannot market) that closer gearing steps are more important to serious riders than wider range. If I were to design a hub it would be a 5s single stage with the 3 middle ratios as closely stepped as practical, and the two outer steps being wider. (anyone out there listening?)