Oval Chainrings for GRX

[Boab]

After last months struggle to get up some hills, I'm looking to tweak the gearing on my gravel bike. I'm currently running bog standard GRX, with 1x 42T chainring and a 11-42T XT cassette, which is great for my local multi-surface riding, although I'm always hunting for the correct gear if I stick to the road. I was thinking of just replacing the chainring with a 38T Wolf Tooth Elliptical 110 BCD Asymmetric 4 Bolt for Shimano GRX, but I'm wondering if that'll be enough to get me round the Moors 100 and especially the BB200. Alternative options appear thin on the ground, with just the Garbaruk GRX Oval that I can find, unless I want to replace the entire crankset and get a Rotor. The Garbaruk chainring is substantially cheaper than the Woolf Tooth one, but as it's made to order, it comes with a bit of a lead time.

If I wanted to approach this from a slightly different angle though, so that I can stay with a larger front chainring and not effect road performance too much. I could instead get the replacement Garbaruk rear derailleur cage, jockey wheels and a bigger rear cassette. Although the jumps in the cogs are slightly different to the XT one, especially five and six, which I find myself in quite a bit.

Shimano - 11-13-15-17-19-21-24-28-32-37-42
Garbaruk - 11-13-15-17-20-24-28-32-36-42-[46|48|50]

Has anyone used any of the Garbaruk stuff...?
Or does anyone know of any other replacement chainrings for GRX...?

[AndyTheBikeGuy]

I've used Superstar chainrings on a couple of my bikes, never had any issues. They're low on stock but there's a 36t in Black in stock.
https://www.superstarcomponents.com/en/ ... w-wide.htm

I've not used it on GRX but I've replaced 105 chainrings with these on a couple of occasions.

[Boab]

I've used Superstar chainrings on a couple of my bikes, never had any issues. They're low on stock but there's a 36t in Black in stock.
https://www.superstarcomponents.com/en/ ... w-wide.htm

I've not used it on GRX but I've replaced 105 chainrings with these on a couple of occasions.

GRX has a funny bolt pattern, Superstar don't make one that fits AFAIK.

[Dyffers]

I have an Amber ring and a mate has a Garbaruk ring and we've both been very happy with them.

However, on the subject of gearing, I use an oval 36T on my rigid 29er...except for events like the BB200 when I switch it out to a 30T Superstar ring. Every year halfway round the BB I tell myself I don't need my biggest gear but I damn well need a smaller gear. 30x42 just about satisfies that. Of course, Your Fitness May Vary.

Might it be cheaper / easier to procure a second hand Shimano 104bcd four bolt chainset that you can put a cheap ring onto for occasional use as a straight swap for your GRX chainset when you're doing mainly off-road events?

[AndyTheBikeGuy]

GRX has a funny bolt pattern, Superstar don't make one that fits AFAIK.

Apologies! How foolish of me to assume that Shimano would keep their already odd standard...standard....

[Boab]

I have an Amber ring and a mate has a Garbaruk ring and we've both been very happy with them.

Not come across Amber before. Maybe I have the wrong website, but the photos look identical to those on the Garbaruk website... :shrug:
https://amber-bikes.com/110-bcd-shimano-grx

However, on the subject of gearing, I use an oval 36T on my rigid 29er...except for events like the BB200 when I switch it out to a 30T Superstar ring. Every year halfway round the BB I tell myself I don't need my biggest gear but I damn well need a smaller gear. 30x42 just about satisfies that. Of course, Your Fitness May Vary.

Might it be cheaper / easier to procure a second hand Shimano 104bcd four bolt chainset that you can put a cheap ring onto for occasional use as a straight swap for your GRX chainset when you're doing mainly off-road events?

The intention is to buy a "proper" MTB for doing these kinds of thing in the future.

[phy7tes]

Might it be cheaper / easier to procure a second hand Shimano 104bcd four bolt chainset that you can put a cheap ring onto for occasional use as a straight swap for your GRX chainset when you're doing mainly off-road events?

I've wondered about this but would the increased axle length of a mtb crankset cause chainline issues on a gravel bike with a narrower BB? Even more so with a boost crank?

[Dyffers]

I've wondered about this but would the increased axle length of a mtb crankset cause chainline issues on a gravel bike with a narrower BB? Even more so with a boost crank?

People worry too much about chainline and, to a lesser extent, Q factor.

If the ring clears the chainstay, all good. If you have to run it in the outer ring position, well then it will be slightly less efficient and wear slightly quicker in that climbing gear, but how much are you actually going to ride in that gear? Not long.

My Boost Santa Cruz fits a 36T oval chainring in the middle position of an SLX triple 104bcd non-boost (or 'chainset' as they were just called back then ) with enough clearance from the chainstay. So suck it and see, and you'll get youre money back on the cranks on the classifieds in the current market if they don't work out.

Edit to add: I don't know if any of the gravel bike frames use road BB width standard, but that's where you might have to admit defeat putting an older MTB chainset into some new standard width pressfit BB, but GRX should be swappable?