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spires from Carfax

a new bicycle?

Life, Technology, — June 2013

I've been very happy with my old three-speed over the last three years and it's still a fine bike for getting around Oxford, but I'm thinking about buying a new bike.

There are a few problems with my current bike:
* with steel wheel rims, the caliper brakes work very poorly when it's wet.
* the relatively high gearing makes hill-climbing difficult. I can just heave myself up Headington Hill, but it would be nice to be able to spin up a bit more comfortably.
* there have been occasional failures - my indicator spindle got stuck (locking me into 2nd gear), one of my brake cables broke, my shifter needed replacing, and so forth.

None of these are a real issue for commuting around Oxford, but:
* I've started going on recreational rides out of town. These haven't had hills I couldn't cope with, but it's been a real heave on a few occasions.
* I'm going to be using a baby seat or trailer at some point, and hauling a baby and trailer (or seat) will make the gearing a bigger problem.

The bicycle I'm thinking of buying is a Kettler, which is a reasonably respected German brand selling online into the UK. This would give me coaster brakes as well as the rim brakes and a significantly better gear range (with an 8-speed Shimano Nexus hub), plus a parking lock and dynamo lights as a bonus. Currently on sale at under £300, this won't break the bank or leave me (more than usually) paranoid about theft, but is a real bike, not a BSO.

Do my cycling friends have any comments on this, or any suggestions as to alternatives?


  1. There are two versions of the Nexus hub gearbox - one with a brake and one with out. If you are expecting a coaster brake, make sure of the model gearbox fitted :-)

    Dynamo hubs are all over the place now, and with strong rare earth magnets in them, getting scarily efficient.

    Comment by Matthew — June 2013
  2. The ratios you get with the Shimano Nexus hub gearbox are not even, which can be quite irritating - the biggest gap in the ratios ends up being the one you want to use to climb hills. The big advantage to hub gearboxes is that you can shift while under load (in particular, if you choose the wrong gear going up a hill). The Nexus generally have a good reputation.

    As Matthew noted, some Nexus have coaster brakes, some don't. I'm also not a fan of coaster brakes - give me good disc brakes any day. They can require more maintenance though: many hydraulic designs will get air into their system if you turn the bike upside down and cable disc brakes are usually rubbish, because they typically only act on the pads on one side.

    I would also suggest hills are always "a heave", no matter how good your gears! The same amount of energy is required, gears just let you adjust your cadence (which can be important, but less so than you might hope).

    A good modern hub dynamo can be great, but many are complete rubbish (poor weatherproofing, poor efficiency). No brand name is mentioned in this case, so it's a bit of a lottery. Given they're using halogen lights instead of LED lights, don't get your hopes up too high - a good commuter lighting system might cost more than this whole package... 8-)

    Comment by Andrew — June 2013
  3. The Kettler bikes have the coaster-brake Nexus, though it's only mentioned in the PDF brochure. They have rim brakes on both wheels, but driven by a single control - using some anti-lockup device they claim distributes the braking over both wheels - and under UK (EU?) law they're required to have two independent braking systems.

    I don't know why they have halogen lights - the similar German models seem to have LEDs. But my current lighting system is a very basic pair of 3-LED lights, so I think this will be an upgrade anyway.

    Comment by danny — June 2013
  4. The Kettler's look nice, but I'm not a big fan of suspension forks - unnecessary weight. Regular cycling gets you used to a little bumpiness. The Topeak child seats are good.

    Comment by Andrew — June 2013
  5. I agree with the other Andrew, and I meant to comment on this in my first post: suspension forks on a bike like this are heavy, do very little good and do not last.

    Comment by Andrew — June 2013
  6. Ok, so a minus for the suspension forks. Mostly I'm not doing anything too bumpy anyway, and apart from a terrible stretch of the towpath in north Oxford I haven't hit anything that made me wish for suspension. Mind you, I've only done three to four hour rides...

    The real selling point for the Kettler is the price. The best fit I could find looking at the offerings from the local shops is a Kona Dr Good, but that's 2.5 times as expensive.

    Comment by danny — June 2013
  7. The Dr Good looks like a different geometry - the Kettler will be a more comfortable, upright ride. In favour of the Dr Good is that it's an aluminium frame (so much lighter, but maybe more fragile) and has disc brakes (front only and mechanical?).

    If you do a lot of riding in the wet, you *really* want disc brakes (preferably front and back, and definitely hydraulic). If you just get caught in the rain occasionally, calliper brakes are tolerable.

    Regarding broken cables on your old bike - this happens to the best bikes.

    As for hill climbing - derailleurs are better for real climbing, but the Nexus should be okay for normal hills.

    Suspension - the main reason to have suspension on a bike (in my opinion) is to improve control (keeping the wheels in contact with the ground). Comfort is achieved through a better saddle and maybe a suspension seat stem (which you have on the Kettler). If you make the suspension provide a comfortable ride, it ends up being too soft.

    Comment by Andrew — June 2013
  8. Can't you keep it simple, no fancy gearing, just a sprocket wheel and chain? I've seen many bikes like so, couriers amongst them, flying along at knots of speed.

    Comment by DL — June 2013
  9. The geometry was one reason for picking the Kettler. The Kettler has an aluminium frame too, and it does have the Shimano coaster brake on the rear hub in addition to the caliper brakes, so it would give me something that will work in the rain. OTOH, it may take some getting used to not being able to back-pedal.

    Comment by danny — June 2013
  10. I think the main thing that annoys me about coaster brakes is not being able to easily spin the pedals into a more favourable position before starting. It's something you just do without thinking, and suddenly not being able to do it is annoying. Admittedly, the coaster brakes mean you stop with the pedals level much of the time.

    I also wonder how long they last - brakes imply friction, wear and heat - not something you want happening inside your gearbox. Hub gearboxes are fiendishly complex, and pulling one apart to service them is only practical on the expensive models.

    Comment by Andrew — June 2013
  11. Lest I put you off the Nexus coaster hub, our family hired four bikes, three of which were fitted with Nexus coaster-braked hubs, to ride around Lake Burley Griffin. I chatted with the mechanic at the hire place after our ride about the reliability of the hubs in hire use. He told me their bikes were about two years old, and none of the hubs had failed. If they can survive hire use, they can probably survive anything you will throw at them... 8-)

    Comment by Andrew — June 2013
  12. Thanks Andrew! There seem to have been some problems with older Nexus 8 hubs, but the current ones really do seem to be pretty much maintainance-free - you're supposed to put grease in them every six months or so, and have them serviced every 3000km, but a lot of people don't seem to bother with that and have no problems.

    How did your family cope with not being able to back-pedal?

    Comment by danny — June 2013
  13. The girls didn't complain about the brakes, although I must admit I locked the back wheel a couple of times. Ben, my youngest, had the only derailleur bike and had only ever ridden around the local oval - he took off like a demon, wobbling all over the place at speed and terrorising everyone else on the bike track, with me struggling to keep up and shouting "Keep LEFT!" and "SLOW DOWN!" - he had a ball, but I'm not sure he braked once. Even the grumpy teenager grudgingly admitted that she enjoyed herself. Ben has since got a 3-speed coaster-braked bike - he's not so keen on the coaster brakes.

    Comment by Andrew — June 2013
  14. Damn. I should have listened to Matthew - after all of that the bike doesn't have coaster brakes, it has the SG-8R31 hub instead of the SG-8C31. I'm not imagining that the brochure at http://www.kettler.co.uk/wp/wp-content/uploads/KETTLERBikeBrochure.pdf says "Includes back pedal braking"?

    Comment by danny — June 2013
  15. Cheap modern calliper brakes on brushed aluminium rims will deliver braking in the wet no problem (you can't brake anymore than the grip of the tyres anyway).

    Disk brakes are marginally better in the first rotation at clearing off the water, but are more fiddly and can be broken by turning the bike upside-down or getting chain lube on them.

    Derailleur gears allow you to ride up hills at a slower speeds, using less power, but maintaining an efficient pedaling cadence. If you are doing long rides with hills they are essential.

    Inner-city cycle couriers ride around on single speeds because they are cheaper to maintain but they spend every day on a bike, can ride with a lot of power at different cadences without trashing their knees and don't climb many hills.

    Comment by David — June 2013
  16. Modern internal hubs have gear ranges that match derailleurs - the Nexus 8-speed I was looking at spans 304% - and I'm never going to be a racer or a high-speed tourer, so that's plenty. And the robustness and low maintainance of internal gearing appeals to me. I've never once in 3.5 years had the chain on my three-speed come off, for example.

    Disk brakes are supposed to be better in the wet, but still don't work as well as in the dry. The attraction of coaster brakes is not the stopping power, but the consistency - the braking is unaffected by the weather, leaving the tyre grip as the constraint, as you say. So what I was hoping for was a bike with rim brakes AND a rear coaster or drum brake.

    Comment by danny — June 2013
  17. I had the same experience with a different manufacturer - their website clearly stated the bike had an 8-speed Nexus with non-coaster brakes, but what they shipped was a 3-speed Nexus with coaster brakes. Bait and switch.

    My other bike has "modern calliper brakes" - yes, it will stop in the wet, but the response is horrible: nothing for one and a bit rotations then they grab hard (probably because I'm squeezing too hard). The Avid hydraulic disc brakes on my MTB have a very nice feel and are consistently responsive, wet or dry. Admittedly, the brakes on my MTB probably cost more than the whole Kettler. I've had this bike upside down a number of times (not always intentionally!) and there has been no problem, but this is a feature of the Avids. Shimano's hydraulic system can get air in the system if you invert the bike, and it's a complete bastard to get it back out.

    Hub gears are essentially maintenance free, but don't leave the bike out in the weather - they can still suck moisture in and this will ruin them, and when they go wrong, they go completely wrong.

    I don't buy the "Nexus hub match derailleurs range" claim - I've ridden both and it's just not true. Derailleurs will give you better hill climbing and a better top speed for less effort and less money. All I do to mine is give 'em a bit of lube every few rides - no adjustment, no cleaning (the right lube makes a big difference here).

    The big advantage to hub gears is being able to down-shift under load. If you're popping chains off on your derailleur, it's either this (down-shifting under load) or it isn't set up right. I think I've popped the chain off my MTB 3 times in about three or four thousand km, and every time it's been my own fault. Also, correct chain tension is critical on a hub-geared bike, as there is no derailleur to pick up any slack, and if you pop the chain off a hub-geared bike, you'll be walking home.

    On the subject of price, cheap bikes are better than they have ever been before... but mid-priced bikes are better again. Even if you can't afford it now, have a look at the more expensive bikes so you have some perspective. And if you're enjoying riding, it might be worth spending a bit more to get just what you want - some bike shops specialise in putting something together for you, rather than selling something they pulled out of a cardboard box (of course, this costs more, and if someone nicks it, you'd be very sad).

    As far as bike-in-a-box manufacturers go, Giant are decent quality and can be found everywhere for reasonable prices.

    Comment by Andrew — July 2013
  18. Bikes do seem quite cheap - cheaper here than in Australia, I think - but I'm not going to venture past mid-priced. If I bought a £2000 carbon-fibre frame and spent a similar sum putting wheels, etc. onto it, I'd never dare park it anywhere in Oxford, not without five kilograms of locks on it anyway!

    Comment by danny — July 2013
  19. Have you had another look at the Kona Dr Good? It seems a reasonably good fit to your requirements. But... the model shown on Walton Street Cycles is old - the current model has mudguards (which are a great invention) and the price isn't that attractive - bike shops in Aus have it for about $730. Don't underestimate the value of those mudguards as it's often hard to get a good fit with after-market mudguards.

    Comment by Andrew — July 2013
  20. I ended up keeping the Kettler. The aluminium rims should give me better braking, so the package is close to being an unmixed improvement on my current bike. There will be another post once I've had a chance to use it!

    Comment by danny — July 2013

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