A 1×9 Conversion

A couple of weeks ago, we had a lively and interesting conversation here on the blog about the pros and cons of simplified 1×9 derailleur drivetrains. In the post that launched the discussion, I brought up the fact that I rarely, if ever, use anything other than the center chainring on my city bikes:

I’d say that I’m going to give a 1×9 drivetrain a try, but the fact is, I’ve effectively been using a 1×9 drivetrain for a number of years. You only have to look at my crank to see what I mean; the outer ring was replaced with a chainguard long ago, and the inner ring has zero wear on it. I do plan on replacing the triple with a single crank, if for no other reason than to make it official.

Well, yesterday afternoon I “made it official” by swapping the Sugino XD2 “Quickbeam” crank and 110mm Shimano UN54 bottom bracket on my LHT for a Sugino RD2 track crank (for 3/32″ chain) and 103mm Sugino BB-103 bottom bracket. Because I’d already removed the front derailleur and shifter/cable, there was nothing to do other than swap the BB and crank. It certainly wasn’t necessary to replace the crank, but I no longer had a need for a double or triple on this bike, and track cranks provide a few advantages:

  • Track cranks are lighter than doubles or triples. This is the most often cited, but least important reason for swapping cranks as far as I’m concerned.
  • Track rings are less likely to cause chain derailment. Because most chainrings designed for doubles and triples have a small number of shortened teeth to improve upshifting, at least in theory, they’re more likely to cause chain derailment. Honestly, in practice I haven’t found this to be the case (I’ve yet to drop a chain on a road bike set up sans front derailleur), but it’s something to be aware of if you’re running a double or triple sans derailleur and regular derailments become an issue.
  • Track cranks have lower Q-factors than doubles or triples. This is the big one, and it’s certainly the most compelling reason to run a dedicated 1×9. Q-factor (aka “tread”) is defined as the horizontal width of the cranks measured from the outside to the outside (where the pedals attach). The lower the Q-factor, the narrower the distance between the rider’s feet, and the less strain there is on hips, knees, and ankles. A low Q-factor places the legs in a more natural position, and because we walk with our hips, knees, and feet in vertical alignment, it’s not really possible to have a Q-factor that’s too low. Besides providing this significant ergonomic advantage over double and triple cranks, low Q-factor cranks also provide more pedal clearance while cornering.

I’m happy to report the swap went without a hitch and the new crank looks fabulous. On the 103mm BB, the chainline is 45mm, which perfectly aligns the chainring with the center of the rear cluster (see above). The major plus is that the Q-factor dropped by a full 20mm, from 165mm with the XD2, down to 145mm with the RD2. This is not an insignificant difference, and I’m sure my worn out knee will be thanking me for it in the coming months.

The only remaining question is what, if anything, to do about a chainguard. Because I don’t like the feel of my pant cuff rubbing a chainguard on every pedal stroke, I often ride with a cuff strap anyway, so I’m going to go without a guard for the time being and see how it works out.

46 Responses to “A 1×9 Conversion”

  • Pete says:

    This thread oughtta last all week…!
    Is a 3/32 chain the same as what is normally sold as “9 speed” chain?

  • Alistair says:

    Beautiful, I think it communicates purpose too. Like a man with carrying a single wrench tells a story that a man carrying a toolbox doesn’t.

    As for chain guards, you could bypass the whole conundrum and get yourself some pants that jive with bikes. Like the Belmont Stealth Pantaloons from Clever Cycles.
    https://clevercycles.com/2010/04/24/sshhh-introducing-belmont-stealth-pantaloons/#_

    “Below the knee, they taper to a small opening, meaning that you won’t need a strap or to abuse your socks. They are hemmed on the long side, so your ankle remains covered even when your knee is sharply bent, but the small opening means you can’t step on the fabric at the heel even if it’s way too long. ”

    These photos show them with bikes you’d like http://www.flickr.com/photos/cleverchimp/sets/72157623797960209/show/

    Cheers, Alistair

    P.S. I cuffed when when I commuted – after all I had a get-ready ritual anyway. But this summer working from home I just bought a chaingard, don’t want to cuff just to nip out for groceries.

  • Alan says:

    Hi Pete,

    “This thread oughtta last all week…!”

    Hey, maybe I’ll take the week off! :-)

    “Is a 3/32 chain the same as what is normally sold as “9 speed” chain?”

    Yes. In fact, all derailleur chains have a 3/32″ inner diameter and are classified as 3/32″ chains. It’s the outer diameter that varies depending upon the number of rear cogs.

    The reason I specified 3/32″ specifically is that some single speed and fixed gear drivetrains use 1/8″ chains and sprockets. To use a track crank on a derailleur bike, the chainring must be compatible with a 3/32″ chain.

    Regards,
    Alan

  • Alan says:

    Hey Alistair,

    Thanks for the tip about Clever Cycles’ Belmont Pantaloons. I saw those when they debuted, but I’d forgotten about them in the interim. They look super.

    Regards,
    Alan

  • Lee Trampleasure says:

    Remember when ten speeds was enough? My first bike was a Legnano brand, derailleur drive three speed (one of those bikes I got rid of in my ‘youth’ that I’d love to have now).

    I like the idea of stripping off the front gear apparatus, but if I do I’ll probably keep the old crank and derailleur for tours–when carrying a heavy touring load I really enjoy those telephone pole (granny) gears.

  • Bryan @ Renaissance Bicycles says:

    In similar fashion, we’ve put the final touches on a Velo Orange Polyvalent that is meant as a commuter / city bike. It has a Sugino track cranks + Shimano 1×9 drivetrain coupled to a Dia-Compe Silver thumb shifter.

    http://www.renaissancebicycles.com/gallery/?album=20&gallery=65

    Like you said, this is really a great setup for commuting and errands. There are enough low gears for hills and hauling, while still maintaining simplicity. And on the half-dozen rides so far, the lack of a chainguard has not been an issue.

    We’ll post some details of the build this coming week.

    Bryan

  • dwainedibbly says:

    This chain guard would look really good on that bike. If you’d rather support a local shop, ask them to order it for you. Velo Orange offers wholesale pricing to bike shops.

    http://www.velo-orange.com/voalpoch.html

  • Lovely Bicycle! says:

    I like derailleur gearing sans front derailleur, and would probably use that system in leu of IGH for transportation if I lived in a hilly area.

    We converted one of my vintage mixtes from a 10 speed to a 5 speed a few months ago and it’s fantastic. We did retain the original crankset designed for a double and I have not had any problems with it, but you make a good point about the benefits of track cranksets.

  • Alan says:

    @Bryan

    That’s a sweet build. I like the mid-cage RD, and the Fatty Rumpkins look super with those fenders. Classy city bike…

    Regards,
    Alan

  • Saddle Up says:

    I think the Sugino Chainring gaurd is the most elegant solution for a chaingauard … http://www.velo-orange.com/suchgu.html . 1×9 drivetrains look the business, very nice. I really like the evolution your LHT is taking.

  • Phillip says:

    That’s a righteous looking build Alan. It’s looking a little more serious bid ‘ness and a little less Opa fiets. As for chainguards, I have a hard time working up any enthusiasm for them. It’s probably a generational thing with me. I’m 48 yrs old and took up road riding in the 70’s when chainguards were the epitome of fredness. I’ll never argue their functionality though. Still your bike looks quite nice without it. I never get dirty cuffs because I’m one of those guys who still rolls ‘em up. In the winter I wear wool knee socks to cover exposed flesh. I suppose I could start riding in a pair of plus 4’s and lose the rolled cuffs. Oh well, fashion considerations aside does the chainguard ever interfere or complicate wheel removal or chain repairs?

  • Alan says:

    @dwainedibbly

    I wonder if the V/O chainguard will work with a wide range cassette?

  • Alan says:

    @Saddle Up

    I had that chainguard on the XD2 crank I just removed. It works quite well, but it takes the place of a chainring, so it requires at least a double or triple crank.

    Regards,
    Alan

  • Alan says:

    @Phillip

    “That’s a righteous looking build Alan. It’s looking a little more serious bid ‘ness and a little less Opa fiets.”

    Hey, thanks!

    “Oh well, fashion considerations aside does the chainguard ever interfere or complicate wheel removal or chain repairs?”

    In my experience, open chainguards don’t interfere at all, but fully enclosed chaincases can make on-road repairs more difficult.

    Regards,
    Alan

  • Mike says:

    Would the chain guard shown on the Civia Bryant work on a 1×9 or derailleur gearing? While I’m not getting the Bryant yet (soon!), I’ve contacted Civia and it’s available for order as a separate part. I plan on using it on a fixed gear build.

    As far as I know it’s always in the image shown on Civia’s home page:

    http://civiacycles.com/

    I think it’s a gorgeous design.

  • Garth says:

    Looks nice, Allen. I found the 8 speed a lot easier to friction shift with than the 9 speed. I use a Sugino PX crank with 42/28 TA sprockets. It’s very nice. I rarely use the 28t, but left it on because it’s so light and small and found the derailleur very useful in keeping the chain on while riding through potholes. Good Luck!

  • Caspar says:

    If you shorten the chain so it just clears the big cog on the cassette (you might not use that a lot?) you have more tension on the chain and it is less likely to fall of the chainring on rough surfaces.
    I’ve found shorter cage RDs to also help with that.

    Nice build

  • Cycling For Beginners says:

    The bike looks sharp now, but I also like the VO Alloy Polished Chainguard for clean riding with no special clothes or rolling of cuffs.

  • j. pierce says:

    “it’s not really possible to have a Q-factor that’s too low.”

    I don’t know about whether it’s possible to have a Q-factor too low – on my newer ride, with the track crank and IGH, I’m having a fair bit more knee pain than I did on my old ride. Now, a bit more has changed between these two bikes than just the Q factor; but I find what immediately alleviates the pain is sliding my foot to the outside of the pedals, sort of half-on, half-off. – effectively increasing my Q-factor.

    Now, I know the plural of anecdote is not data, but but that’s just my take on it. I also remember those pedal spacers sold as “knee savers”, which would seem to indicate I’m not the only one – I just think (IMO) that narrow Q isn’t necessarily “good” while wide Q is “bad”, I think it’s something, like saddle and bar height and angle that needs to fit our bodies and how we cycle. That said, many crank setups are much wider than is probably comfortable or good; but I don’t think super narrow Q is always the answer either.

  • Cal M. says:

    Great article. By the way, it was good to see at least a little grime on your cassette. Your photos of your Bikes are some of the absolutely best!

  • Saddle Up says:

    Alan there is a chainring bolt set available that includes spacers and longer bolts which allows the use of the chaingaurd you’ve been using on your XD2. I believe it’s also from Sugino.

  • Alan says:

    @Mike

    “I think it’s a gorgeous design.”

    I agree. I’ll look into it.

    Thanks!
    Alan

  • Alan says:

    @Caspar

    “If you shorten the chain so it just clears the big cog on the cassette (you might not use that a lot?) you have more tension on the chain and it is less likely to fall of the chainring on rough surfaces.”

    Thanks for the tip. It’s currently set-up so it’s nearly maxed out on the 46/34 combo. I may swap the 46 for a 42 at some point; if I do, I’ll be sure to remove the appropriate numbe of links.

    Regards,
    Alan

  • Alan says:

    @j. pierce

    “I just think (IMO) that narrow Q isn’t necessarily “good” while wide Q is “bad”, I think it’s something, like saddle and bar height and angle that needs to fit our bodies and how we cycle. That said, many crank setups are much wider than is probably comfortable or good; but I don’t think super narrow Q is always the answer either.”

    I agree – I overstated a bit. What I should have said is that a majority of people will probably do better with a lower Q-factor that what is the norm on today’s bikes. Certainly, for those with wider than average hips, larger than average feet, or a toe out condition, a wider Q-factor may be more ergonomically correct. Thanks for pointing this out! :-)

    Regards,
    Alan

  • Alan says:

    @Saddle Up

    “Alan there is a chainring bolt set available that includes spacers and longer bolts which allows the use of the chaingaurd you’ve been using on your XD2.”

    Great tip. Thanks!

  • Vivien says:

    Hi ! I guess you gained some weight on the drivetrain !
    But what about the horizontal torsion of the chain on the upper and lower gears ? That is, with 9 rings and only one ring, on the 1st and the 9th (2nd and 8th as well actually) your chain is not straight and the efficiency should be lower.

    Great site, thanks for that !

  • Alan says:

    @Vivien

    “But what about the horizontal torsion of the chain on the upper and lower gears ? That is, with 9 rings and only one ring, on the 1st and the 9th (2nd and 8th as well actually) your chain is not straight and the efficiency should be lower.”

    Hi Vivien,

    The Human Power Journal did a fairly rigorous study of derailleur drivetrain efficiency (http://www.bhpc.org.uk/HParchive/PDF/hp50-2000.pdf) and found losses due to crossover to be negligible (<0.5%) when compared to other losses introduced by factors such as cog size and chain tension (chain tension was a biggie). From the study:

    “It was found that chain-line offset and chain lubrication have a negligible effect on efficiency under laboratory conditions. Calculations of frictional loss resulting from offset indicate that this loss should be small compared to those produced by other mechanisms. This was verified experimentally. Lubrication effects on chain efficiency were tested using three different chain lubricants under a variety of test configurations. No significant quantifiable effect of lubrication could be inferred from these tests.”

    This doesn’t address accelerated wear, which may be an issue, but I think we can be fairly sure the loss in efficiency from shifting across 9 cogs is not an issue for non-competitive bicyclists, particularly if the chainring is centered on the cassette.

    Regards,
    Alan

  • Bob says:

    If anyone out there runs a 1x drivetrain and has issues with the chain derailment the Paul chain keeper will solve them. http://www.thebikebiz.com/Paul_Components_Chain_Keeper_p/com-acc-paul01.htm

  • Fergie348 says:

    One other argument in favor of a short cage rear mech. The shorter distance between the guide pulley and tension pulley will cause the chain to ‘wrap’ more around the lower part of the chainring, making front derailment less likely. It also keeps the chain higher above the riding surface, which cuts down on water and dirt splashing up onto your drivetrain.

  • Morpheous says:

    Nice, now complete the conversion with an Alfine 8 sp IG Hub!

  • Alan says:

    @Morpheous

    “Nice, now complete the conversion with an Alfine 8 sp IG Hub!”

    Thanks!

    It’s possible to do an IGH conversion, though this isn’t the ideal frame with its vertical dropouts. Anyway, I’m really liking the simplicity of the 1×9 derailleur set-up; it’s super clean and it performs quite well.

    Regards,
    Alan

  • ted says:

    Cal m. beat me to the punch!!! I went back to clean my glasses because I knew it couldn’t be true! I still can’t beleive my eyes, but Cal M. DID see it too, so maybe…

  • Alan says:

    @Cal & Ted

    “By the way, it was good to see at least a little grime on your cassette.”

    Sorry to spoil your fun guys, but you’re looking at wax flecks that’ll brush right off with a quick swipe of a soft brush. Maybe next time… :-)

  • j. pierce says:

    I just got one of the VO chainguards ( http://www.velo-orange.com/voalpoch.html ) that dwainedibbly posted, for my wife’s bike. It’s a lot sturdier than the previous guard VO carried, and a real nice piece of kit. Looks even nice than the photos. Definitely worth the 25 bucks, and I like the BB mounting over trying to kludge something together to mount a simpler guard on a bike not made for it.

    Was thinking of installing one on my bike as well, but be forewarned – on track style cranks, there may not be enough clearance between the ring and the crank arm to make it work. It seems like with a little work, you could modify the guard to fit in those cases, but for those adverse to hacking up new pieces of gear, it’s a fair warning.

  • DRikardo says:

    Extremely beutiful and clean bike!Nice pictures too!
    One thing is bewildering me.
    The new Sugino RD2 track cranks with the logo of kings crown and letter S , do look almost as good as good old the campy c-record , but link in the text leads to a completely different crankset??

  • Patleeman says:

    I love the articles you’ve been running on 1×9 setups.

    I run a 1 x 9 setup on my Trek 1.2 and I love it a lot. I did the build on the cheap so all I bought was the Brake levers ($30), Shimano Deore xt thumb shifters ($40), BBG Bashguard($20) and Ngear Jumpstop ($8).

    The bike is such a mish mash of parts due to the fact that the kid I bought it from had the front end stolen off of it and I had the assorted parts to rebuild the bike.

    Here are some pictures of my setup. http://www.flickr.com/photos/patleeman/sets/72157624760827564/

    Before I got the bashguard/jumpstop combo, I used to throw the chain at least twice a ride. It’s probably due to me being cheap and using the road ring that came on the triple crank set but my goal was to spend as little as possible. The bashguard/jumpstop combo cost less than $30 bucks and was well worth it. Once I put the set on I haven’t had any chain throwing problems. The chain does rub against the inside of the bash guard in the highest gear but I seems to have worn the bashguard down enough where it doesn’t bother me anymore. During my research the BBG/Jumpstop solution seemed the cheapest and simplest setup. It’s not the prettiest thing but it works like a champ.

    I love the 1×9 thumb shifter setup. The bike gets about 150 miles a week and after the initial setup it’s been riding beautifully. The 1 x 9 is perfect for riding in NYC and I find myself using the full range of gears each day during my commute. It’s just enough to go fast down hills and also get over the bridge every day with ease.

    I highly suggest using this type of setup for city riding!

    Jumpstop – http://www.gvtc.com/~ngear/
    BBG Bashguard – http://www.bbgbashguard.com/

  • Lee Trampleasure says:

    For my “one bike for all needs” (commuting, touring, errands) I’m sticking with my 3×9 configuration, but it seems to me that for a commute/’round town bike, the 1×9 is an ideal mix of 3×9 and fixies

  • j. pierce says:

    I’m rebuilding my wife’s bike, and we needed a new crank. Her’s was an old, Polish, “Tyler” brand 10-speed someone had made a single speed by removing a chainring and the derailleurs. We’re making it a three speed with a new wheelset, but being stuck with a 52 up front makes the the gearing on an SA hub useless; it’s a cottered crank with a pressed on ring, so we needed to replace the whole unit. She wanted a crank with a similar vintage look, and after having a hard time finding a used one we were happy with, we ordered the single-speed crank from Electra’s Ticino line. (The new VO cranks weren’t available at the time, or I might have gone with one of those) It’s actually a really nice looking crank, but the part I found interesting (and perhaps relevant to the conversation at hand, hence my rambling) is that it has the chainring guard, akin to the Sugino guard Saddle Up mentions above, but it’s actually set up like a triple, with one guard ring on each side. I feel like this could function even better for keeping the pants out of the chain and potentially grease free. Might help with dropped chains, too, although I don’t know if it leaves enough freedom for the chain to flex and reach all the sprockets of a 1×9. It looks like it could; before I recycle/break down her old wheel, I’m going to at least see how it plays with the 5-speed hub.

  • Richard Saffran says:

    There’s a (much pricier) alternative if you want to maintain an ultra-wide gear range to handle steeper terrain:

    http://www.bikerumor.com/2008/09/04/bionicon-b-boxx-internal-gearbox-crankset/

  • Kings County says:

    I have a 1×7 set up for a while now, with no problems. I use a Third Eye Chain Watcher, which mounts where a front derailleur would be, and prevents the chain from falling off on the ‘inside’. To eliminate the chain from being thrown off to the ‘outside’, I use one of those mtb discs that takes place of an outerchainring.

    With a mega-range (11-34 tooth) at the rear hub, you can cover a wide spectrum. In recent times, 36 teeth cogs are being offered on 10 speed cassettes. I think it is Speciallized that has a 2011 bike thats 1×10.

  • EcoVelo » Blog Archive » Paul Chain Keeper says:

    […] A 1×9 Conversion(973 views) […]

  • EcoVelo » Blog Archive » Back in Black says:

    […] A 1×9 Conversion(1,028 views) […]

  • EcoVelo » Blog Archive » The Verdict: No Chainguard Required says:

    […] the past couple of years, I converted my commuter from a triple, to a double, then recently, to a 1×9 with a Paul Chain Keeper. It’s a simple drivetrain that works quite well for how I use it. […]

  • Enrique says:

    I don’t know if a lower Q-factor would be a good ergonomic fit for my legs, which are bowed below the knee. (When I place my feet together, with my legs straight, the knees do not touch.)
    I discovered I get inflammation at the outside of the right knee after riding for about 40 min. By placing my feet on the outer half of the pedals, I rarely ever get that inflammation.
    I want to go without the front derailleur and hope the chain derailment you mention will not happen. For now, I’ll keep the outer chainring (my bike has a 2 x 8 drivetrain) as a toothy chainguard and see how it goes.

  • Tony Dyson says:

    I have a 48 x 11>>32 setup on a Catrike (20″ wheels). According to Sheldon Brown’s gear-inch calculator, this should give me a 28.0 to 81.5 range. This seems to be all I need for commuting around metro Denver. I do like the simplicity.

  • EcoVelo » Blog Archive » Some Thoughts on Internal Gear Hubs says:

    […] same thing, though I probably use more like 6 gears instead of her 3 (I shift too much). In fact, I converted my old Surly from 27-speeds down to 18, then finally 9, and even then I rarely used the entire range. Given our […]

 
© 2011 EcoVelo™