What chain ring for converting a Shimano hollow-tech to a single ring?

Hi all,

I’ve got a flat-barred road bike and want to get rid of the front rings and make it a x1.

I think it’s a 9-speed at the rear.

Could you tell me what ring should I buy? I guess around 32 teeth but does it have to be some sort of special one to go x1?

Thanks,

FM

I went for a ‘narrow-wide’ chainring when I went from 3x to 1x. You’re losing the front derrailleur and in the process losing a chain retention device so the narrow-wide teeth help grip the chain better. Not vital I expect but definitely help.

Nothing particularly special but it’s worth getting a narrow – wide (NW) as the chain stays on better especially once you remove the front mech. Also you may need shorter chain ring bolts but some 1x chain rings have a sort of built in spacer so you can use normal bolts

For road, 32 is pretty small- can’t recall what I have on mine, 46 maybe. You definitely want a nonshifting ring and once you’re doing that you might as well get a narrow/wide… They can be really cheap, too, plus chinese branding is awesome, I have a Snail one held on with Cansucc bolts.

What chainset is it? Road and MTB have different bolt patterns.

It was originally a road bike. I can’t remember but it’s defo Shimano.

If anyone can recommend something cheap off eBay/Amazon uk, that’d be great (!)

The crank ought to have a printed model number on the inside of the arms, behind the pedals, you can google that and find the bcd.

What sizes are the current chainrings and which one do you use the most.  Get one similar in size to that.

As for BCD (distant across the bolts) you can measure it https://www.bikeradar.com/advice/workshop/how-to-measure-bcd

If it is Shimano it should be either 110 or 130 so don’t have to be millimetre perfect when measuring.

Once you have the BCD you can just search for something like “130bcd 5 bold narrow wide chainring 40 teeth” and find chainrings such as Deckas that are pretty cheap.

If anyone can recommend something cheap off eBay/Amazon uk, that’d be great (!)

No one can, you need to work out what you have then work out what you can replace in it with. There are some pretty much boh standard bolt patterns, but there are enough random one to make just guessing a risky business.