I own a 2000 model Specialized Ground Control full suspension. The front derailleur is rusty and temperamental so my solution is to remove it as well as 2 chain rings (they are removable on mine) and convert to a 1x7. This bike is not worth high spendings on upgrades so would this work if I just bought a 1x drivetrain specific chain ring and kept everything else stock? Better yet would it even work on the current middle size chain ring with maybe a chain guide attached to keep it held on? If spacers are required that's all good. I am only a novice MTB rider and the bike will predominantly be used for downhill and small jumps, no hectic double blacks or anything. I am aware that 1x7 isn't very versatile but it will be plenty for me to have fun.

7 Answers 7


You have a zero cost solution, which is to keep the front derailleur but remove the cable (and shifter if you like). Then use the FD limit screws to fix it in the right position to act as a chain guide.

You don't need a 1x chainring, in fact using one with a 7 speed chain is probably less than ideal, so you're actually better off sticking with an existing chainring. You may not be able to get rid of the big chainring, or you may need to get shorter chainring bolts if you do, depending on how the big and middle rings are mounted.

  • OP may find that sticking with the middle ring might provide enough gearing range for their normal use.
    – Criggie
    Jun 14, 2019 at 7:24
  • 5
    @Criggie I reckon they will. the reason for keeping the big ring is as a spacer to use existing bolts, or in some case a mount for the middle ring
    – Chris H
    Jun 14, 2019 at 7:43

If the chainrings are in good order, I would recommend servicing the front derailleur and continue to run it as 3x. The reason is that front dérailleurs rust quickly but are often chrome plated and it’s actually easy to remove the rust. If the derailleur is temperamental it is typically solved by replacing the shifter inner cable ($1 on eBay) and readjusting the limit screws.

Yes it will take up some of your time, but it would cost close to nothing and you will probably appreciate the wider gearing on some occasions. Also, as noted by others, you’ll still need the front derailleur as a chain guide so you would still see the rusty thing if you would run 1x.


Yes, it's doable. You'll have terrible gear ratio range but you realize this and don't mind.

Either find a narrow-wide chainring that fits the crank, or leave the middle ring in place. You may need shorter chainring bolts as the existing ones have to be long enough to go through the middle and large rings.

You can remove the shifter but leave the front derailleur in place to act as a chain guide, if you can wind out the lower limit enough or otherwise fix it over the middle ring.


I've done this, converting a bike from 2x11 to 1x11. I removed the big ring, front derailleur, and the shift cable.

I did need parts, but only shorter chainring bolts. If you don't want to do that, you could leave the big ring in place, or rig some kind of shim or spacer.

I did run into one problem, which was that the chain dropped off the chainring several times an hour. There are many gadgets on the market which try to prevent dropped chains. I ended up getting one of them (a chain guide), and I'm quite happy with the bike. But if you want a minimum-cost solution, Chris H's suggestion -- to use the front derailleur as a guide and adjust the limit screws to position it -- sounds good to me.

  • Very helpful everyone, answered all my questions. I reckon I'll try initially with the front derailleur left in place as a chain guide and find out as I go if I need shorter bolts or whether I can fashion a suitable spacer. Cheers everyone!
    – dos_dyall
    Jun 14, 2019 at 12:05
  • why is a chain guide even necessary in this case? i have a 1x11 on my gravel bike, no chain guide and the chain has never dropped off even on rough gravel, forest paths and even short mtb trail passages. Are the chain rings different?
    – stefs
    Jun 26, 2019 at 13:39
  • 1
    @stefs Dan uses the original chainring, which is designed to easily let go of the chain for better shifting. You likely have a narrow-wide chainring designed to retain the chain (as no shifting is necessary). And Dan might be riding MTB trails that are rougher than your gravel roads.
    – MaplePanda
    Jan 29, 2021 at 0:49

I run a small bicycle hobby shop. I have been doing 21 to 7, and 24 to 8 conversions for as long as I can remember.

The conversion can even be done with a riveted crankset that has no bolts in it. I carefully drill out the rivets or spot weld that hold the 3 chainrings together, throw away the big and small ring, and keep the middle ring. Typically in these one piece setups the crank arm is fastened to the middle in 9 out of 10 cases.

Then remove the front derailleur, shifter and cable. I remove between 4 to 8 links from the chain. I have never had any one complain about their chains jumping off the front sprocket. Sometimes I will change the bottom bracket to improve chainline. This conversion has been fool proof for me and my customers.


I have done it too. 3x7 to a 1x7 added a small chain guide just incase. I feel the chain could be tighter but not sure to just buy a new chain(not sure which is best size for the set up) as upgrading a lot anyway or remove a few links but how many??

photograph of the chain ring from above showing a chain guide clamped to the seat tube

  • 3
    Hi, welcome to bicycles! It's great that you got this to work; any additional details you can add about how the bike was originally set up and the changes you made would be useful. What did you use for a chain guide? Did you need to adjust the chain line?
    – DavidW
    Jan 28, 2021 at 20:26
  • Please increase the relevance with edit Note that the question is "can the conversion be done with only existing parts?" so your answer is that a chain keeper needs adding ? The parts about chain sizing are a separate question, and you can search the website for existing questions about sizing a chain.
    – Criggie
    Jan 31, 2021 at 19:01

Not a problem, just remove the front derailleur. If you leave all of the chainrings on the crank, you can change the gear range manually depending on how much gear you want for a particular ride.

  • 1
    This is just Dan's answer, minus all the detail and minus the significant warning that the chain will just fall off all the time. Jun 16, 2019 at 21:51

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.