Convert Your Bike To A 1x / Single Chainring Setup!

Are you thinking of converting to a 1X setup? Jon talks you through easily hacking your drivetrain from a double into a single chainring system.

1X drivetrains are growing in popularity and have already taken over the off-road world. They have also grown in recognition on road, due to their use in professional squad Aqua Blue Sport. For this job, you will need a specific narrow wide chainring, a derailleur hanger extension and some basic tools to remove your old chainrings. You may also require shorter chainring bolts if they do not tighten down sufficiently. We hope you enjoy Jon's latest hack and that it may inspire you to get creative yourself!

Are you thinking of converting to a 1X drivetrain?

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[gcntech]

Are you thinking of converting to a 1X drivetrain? Let us know. 👇

[D.Eldon_]

For many years, I ran a 2x drivetrain on my main road bike with 34-50t compact chainrings on the front and an 11-26t cassette on the rear. This bike is never used on gravel or rough pavement and is never used in mountains (it's mostly used in low rolling hills). After two years of never needing to use the 34t chainring, I converted the bike to a 1x. This was three years ago. I have a SRAM drivetrain and all I needed to do was switch to a 50t SRAM X-Sync 1x chainring at the front and an 11x28t cassette at the rear. 28t was the largest cog my rear derailleur could accommodate. I used that setup successfully for two years (about 10000 miles or 16093 km).

At the beginning of this year, I switched to a 52t oval Rotor QX1 Aero chainring on the front (equivalent to a 54t round chainring) and an 11-32t cassette with a SRAM Red WiFLi rear derailleur with a medium cage. I would have preferred an even bigger chainring -- like a 56 or 58t -- but the only ones I could find were poor quality and did not position the teeth in the correct location. The reason for the bigger chainring is to reduce friction by moving the chain closer to the center of the cassette during most use (a trick used with triathlete and TT bikes).

_Here are some potential problems to avoid:_

*Rear derailleur hanger extender* - The top jockey wheel of a rear derailleur must not only clear the largest cog in the cassette (typically with 4-6 mm to spare) but the track of the rear derailleur as it moves across the cassette must be at an appropriate angle so it maintains an acceptable distance from each cog. Rear derailleurs that are designed for wide-range cassettes are designed with both requirements in mind. All the hanger extender does is enable the top jockey wheel of a standard derailleur to clear a larger cog. It does not change the tracking angle of the derailleur. This means the top jockey wheel may be too far away from the smallest cog if it is beyond its range. The result is poor shifting. The best solution is to get a rear derailleur that is designed for the cassette range you plan to use. If you must use a hanger extender, then be very careful to check the hanger+extender alignment to the wheel. Any hanger alignment errors will be magnified with an extender and that, too, will degrade your shifting. Park Tool Dag-2.2 will help you to both measure the alignment and bend the hanger+extender into the correct position.

*1x chainring* - The most important design feature of a 1x chainring is not wide/narrow teeth -- rather, it is the location of the teeth. Theoretically, you want the teeth to be centered in the driveline to the center of the cassette. If you compare it to a 2x setup, the 1x chainring teeth should be in the middle between the outer and inner 2x chainrings. In practice, SRAM recommends that you favor the outer cog of the cassette by 1-2 mm. This is why a 2x outer chainring is unsuitable for a 1x setup -- it's teeth are too far off-center (toward the outside), which perpetuates the cross-chaining problem to the largest cog. _But here's the problem that catches some by surprise:_ There are some cheap 1x chainrings on the market that do not locate the teeth in the correct position for a proper 1x drivetrain. Therefore, if you decide to experiment on your own (like I have) you need to do your homework on drivelines (a.k.a. chainlines) and measure the current driveline offset of your bike at the rear cassette. Then make sure the 1x chainring you use is compatible with your driveline.

*Chain length* - The chain in the video looked too long. I recommend shifting to the biggest cassette cog, thread the chain through the rear derailleur and around the largest cog and the chainring, then pull the chain together until the rear derailleur cage is pulled nearly as far forward as it will go _without rotating the top jockey wheel too close to the cog._ Mark this chain length and add two links to it. This method takes the most work (and strength) but it produces the best results.

_Tips:_
Road racing frames with shorter chainstays are problematic for 1x because they have more dramatic angles in their driveline when cross-chaining. One way to reduce this problem a little, is to use a 10-speed cassette and rear derailleur. It will move the largest cog closer to the center of the driveline. Some cyclists who criticize 1x for having steps between cogs that are too large will probably blow a fuse over such a suggestion. But I rode a 2x6 drivetrain for many years and never noticed a problem. I could still find an acceptable gear ratio for the cadence I wanted to use. And, when you consider the redundancy in gear ratios of a 2x system, the actual "usable" gear ratios that you have is less. So I have no problem with the step size from 11 to 32t on a 10-speed cassette in a 1x system today. And I doubt I'll have any trouble with an 11-36t, either. Use what works for you and don't let others force you into their idea of "perfection".

If you lube your chain with wax, be aware that 1x systems can take a little more work. You need to manually push a freshly waxed chain onto the wide/narrow teeth of a 1x chainring while slowly turning the crank for the full length of the chain in order to push out extra wax from the gaps in the chain. If you don't, the freshly waxed chain may derail off the chainring when you first use it. Most 1x chainrings have longer teeth than their 2x counterparts, but the tooth length of all 1x chainrings are not the same. For example, the teeth of my Rotor QX1 Aero are 8.0 mm long and the teeth of my SRAM X-Sync are 7.0 mm long. The longer 8.0 mm teeth can make it even more difficult to break in a newly waxed chain because the longer teeth engage the gaps of the chain earlier and must push more extra wax out of the gaps. This may not be a big deal to most waxers because the benefits often outweigh the problems. But it's something to be aware of.

[sfdint]

Just made the switch to a 1x drive system. Can't believe how much it has simplified my ride! I lost a gear or two on the high end, but I'm 70 years old and I can still hit 30 mph without spinning out. Not needing to switch from large to small rings up front, especially when I'm doing a lot of up and downhill, just eliminates a lot of bother and making fine adjustments in the rear after you switch front rings. No down side for me.

[KriegKadaver]

I got a 2017 Trek Crossrip 1, it had a 48/32 chainrings with 11-32 cassette. With shimano Sora 9 speed shifters/derailleurs. I found myself never going to the smaller ring upfront, only trimming. So it was logical to just put a narrow-wide 48t chainring. No other modifications, just removed the shifter cable, front derailleur and switched to 48t narrow-wide chainring. Works like a dream! No more worries about trimming, and for my fitness / endurance rides 1by works great! I do think this is the future. They used 2by and 3by because technology wasn't quite there yet to put many sprockets in the back. Now we have that. 9 is enough for a recreational rider like me, I'm sure 12 will be plenty for more advanced riders.

[ericsmucker]

Old Trek 720
With a 10 speed 11-40 cassette coupled with a 42 tooth wide narrow. Rear derailleur is a Shimano Zee mtb short cage with a Microsoft 10 speed bar end shifter. Works great! Never dropped a chain with this setup.

[peterbee]

I have converted my giant defy with roadlink extender and added a 11 40 shimano cassette. Worked all ok since August last year. Still have ultegra dual rings up front. Spacer needed when adding the mtb cassette.
Works a treat and no roads need you to leave the saddle.

[pastagreyhound]

I have four 1x rigs. Love it. Three are converted from standard and one is the latest SLX 1x11 iteration. Not sure I'd convert my road bikes over though. I did, however, convert an old GT ZR road bike from drop bars to straight and put on a WickWerks narrow/wide 42t CX chainring with 11/36 in the back. Light and quick!

[icyraikkonen]

I really want a video where we go through Jon's attic and see all these bikes!

[dylanmurphy]

How to make a 1X for cheap - stay in the same front chainring

[nicks]

i wish my shed was full of "bits and pieces" like this :(

[frazergoodwin]

So all I need is a Dura Ace Di2 equiped Merckx carbon frameset and I can hack a one by system. Bargain.

[simonguard]

I've just stumbled across my old Pinarello Dogma frameset also in my loft and blow me my 2016 Super Record groupo,
Let the 1 X build commence. 🚵🏼

[scottdesmarais]

I recently converted my Kona Jake The Snake commuter bike to a 1x10. 42t Wolftooth oval chainring and 11-36 cassette. Switched out my 10-speed 105 derailleur for a 9-speed long cage Deore. It works like a dream.

[mcjcg]

I have heard of a Narrow wide before and even seen them on YouTube but this is the first time a someone explained what it was thank you

[Hvaspen]

I have been riding a 1 x for years. Started with a 48t track crank and a 14-28 6 speed cassette on an old steel frame about 30 years ago. Latest is a super lightweight Neil Pryde carbon frame with sram red and a 50t narrow/wide with a 11-30 cassette. Plus many other 1x builds on all types of bikes, Road, Mountain and Hybrid. Always on the lookout for broken left hand shifters that I can strip down to provide a lightweight brake lever.

[deanwong]

For anyone who's curious about a 50t Chainring + 11-42t 11-speed Cassette combination, here's my setup:

50t Wolf Tooth Narrow-Wide Chainring for Shimano R7000 Crankarm.
11-42t 11-speed Shimano XT Cassette on an 11-speed hub without spacer.
Shimano Ultegra RX derailleur with Wolf Tooth Roadlink DM.
116 Chain links Shimano Dura-ace (Any chain suitable for the Chainring will do too).

Although the Ultegra RX has the clutch mechanism, I like that it gives the option of turning it off for smoother shifting. I found the clutch not required on asphalt when paired with the Wolf Tooth Chainring--No chain slips so far after 400miles. On light gravel paths (~2" obstacles), it runs well without relying on the clutch as well. The clutch is still useful to minimize slaps on bumpier trails.

The cassette spacer on an 11-speed hub had me puzzled. While adding the 1.85mm spacer is recommended when pairing an 11-speed MTB cassette to an 11-speed road hub and tuning unloaded appears to validate it, riding the bike revealed otherwise--excessive noise on high gears (small sprockets). The skewed chainline was the main contributing factor after fiddling with the derailleur high limit screw and tension.
Removing the spacer had solved the issue and even with a slightly more skewed chainline on the low gears (large sprockets), the noise was minimal.

If available, I'll suggest going for more than 116 chain links for this configuration to reduce the derailleur extension on lower gears--Shimano sells 11-speed chains with 126 links. Sadly, I'd only found the 116 links version available in the shops nearby.

Hope this might help anyone save a few (mis)steps and pain. Ride on!

[Bav]

11-40 runs nice using a wolftooth hanger (similar to the red thingy) and a medium cage 105.

[prblakeslee]

I dumped my 3X ringset on my trike a few months back and will never go back! . I kept all my stock pieces other than 1x cankset&chainring. Total price was about $40. Total weight loss of bike was 2.0 lbs!
PS: I noted some comments below where posters' kept stock big chainring. Dont do it! Spend a few bucks and get a 1x (thick/thin) chainring. It will save you some frustration.
PSS: Vs swap out rear gears for a 32T+ big ring setup....or even a 10T small-ring setup ($$), this is what I did:
For my daily training stomping grounds (flat), I run a 50T 11x32 I decide to do some hill riding, I simply swap out the 50T chainring for a smaller chainring and all is good. Takes only a few minutes, and only costs the price of a second 1X ring!

[IanLoughead]

I do it on my commuter bike. Even with big hills. It is an older bike with a 7 speed cassette, so I opted for a 40 tooth front ring, which gets me up most hills with the 28 in the rear. It is just easier to maintain, especially in the winter months.

[veloriderkm]

I've previously hacked 1x on 2 cross bikes. First time around: SRAM Red crank with the 53T removed leaving the 39T. I used a short cage SRAM Red rear derailleur and no chain guide or keeper. Dropped a chain several times when in the smaller cogs (11-28 XG1090 cassette) on the rear so I shortened the chain and had fewer drops. On my 2nd time around I used an Ultegra 6800 crank with a Wolf Tooth 42T narrow-wide ring and a medium cage Force 1x RD (11-34 cassette) with 2012 Red shfiters. This setup was quite nice and stayed until I sold the bike.

Next 1x setup on a future build will be Di2 road/mtb component combination.