New outer chain ring replacement - Help please.

JAMESWRIGHT2004

Hi guys,

Need a little help as I can't find a direct answer to my question anywhere else and would also like some advice/recommendations.

First off, my current set-up: I have Shimano Tiagra group with a 9 speed rear and a Triple FSA Vero 50/39/30 front (Its an old Trek bike I use on my Turbo for Zwifting and stuff). But I would like to replace the 50 with a 53 as I find myself constantly in top gear and nowhere else to go. Hoping that would at least give me a little more spectrum at the top end.



Now my problem. I cant find a suitable 53t ring. Mostly because I dont know what I'm looking for - I'm stumped unless there is a direct replacement or it specifically says "Will work with 9 speed triple FSA Vero".

From what I know its a 130mm BCD, and stamped S-9 (which I dont think FSA do anymore) and understand it has "square taper" from reading other blog posts. I found this: https://www.ebay.co.uk/itm/310982217941?ul_noapp=true but was unsure on its compatibility or quality. I would much rather have something one of you guys recommend as its more of a known commodity.

Also would it be a straight swap out from a 50 to a 53 or would I need anything else? Longer chain, spacers etc??

Many thanks in advance.

J

N0bodyOfTheGoat

https://www.planetx.co.uk/i/q/CRFSA/fsa ... -chainring ?

mercia_man

Your FSA Vero triple chainset is a standard Shimano size with a five arm 130/74 BCD. First figure is bolt circle diameter size of outer and middle rings, second figure is size of your smallest ring. There is a vast choice of after market rings to fit, including the one you linked to and also well known high quality suitable chainrings from Stronglight and TA available from, among others, Spa Cycles. A five arm 130 BCD outer chainring suitable for 9/10 speed would be easily fitted. No need to mess around with bottom brackets. "Square taper" is the type of chainset/bottom bracket system your bike has.

However, fitting a 53 ring to your chainset would exceed the official capacity of your Tiagra triple front derailleur. It is designed to work with a 50 tooth outer ring and has a maximum capacity of 20 teeth - that is the difference between big ring and smallest ring. That is what you have at present. You may get away with exceeding your derailleur' capacity if you can move it up enough to clear the teeth of the 53 ring. That might be difficult if you have a braze on front mech rather than a band on fitting which slides up and down the seat tube. You might also have to add a link to your chain. I've had success in exceeding the limits of my front and rear derailleurs on my triple touring bike but it is hit and miss whether it will work OK or at all. But shifting up and down between a 53 outer ring and a 39 middle on your chainset will definitely be impaired if you do this.

You might want to consider changing your cassette to one with a smaller small cog - for example changing from a 12-28 to 11-28 - to give a higher top gear.

Edit: The link from Nitrous Oxide to Planet X above is for a four arm chain ring. As far as I know the Vero triple is a five arm.

JAMESWRIGHT2004

Wow. Thank you for all the info and giving it in so much detail. Looks like I have a few things to look at first, as it not just a straight replacement job.

My cassette is already an 11 so it looks like I’ll have to either a)enter into this idea head on, or b) learn to pedal faster for longer.

Thank you Mercia!

rafletcher

If you don't ever use the bike on the road, then exceeding the capacity won't, in itself, be a problem even if you don't increase the inner ring (that can be taken to a 34 for instance, and the middle to 42 or 44 to keep steps even). However the difference in gearing you get changing from 50 to 53 outer is half the increase you'd get from changing to 11 from 12 as your smallest sprocket, and there's no issue with adjusting the front mech. etc. so I'd get a cheapest Shimano compatible 11 up cassette you can find and fit that. If you STILL find you're spinning out I suggest you increase the resistance on your turbo! , (or fit a larger chainring at that point, with possibly an extra chainlink or two). Braze-on slots can be (carefully) filed out to increase movement, but I suspect you'd be able to fit the 53 without trouble, and with a band-on there's no issue.

keef66

Do you ever use the inner chainring on the turbo??

If not, why don't you swap out the chainset complete for a standard double 53/39 and suitable front derailleur? You can pick both up pretty cheaply on Ebay, and you should be able to set up the left hand shifter to operate as a double.

(Thinking about it I have a 53/39 Tiagra chainset I'll never use again, a used but serviceable105 HT2 BB, and a Veloce FD)

JAMESWRIGHT2004

Thanks all for your input.

rafletcher, I already have an 11 on the cassette so I think upping the size of all the rings may be the way to go (to keep it within the 20 band and keep steps relatively equal). It is also a band on so shouldnt be too difficult.

Keef, On the turbo, no only really use the mid and outer ring, but occasionally I let her loose on the road for longer rides as she is the most comfortable bike I have. And I dont think I would have got up some of the hills on the way to Paris without the inner, so will keep the triple for now. Thanks, though.

JAMESWRIGHT2004

Thanks all for your input.

rafletcher, I already have an 11 on the cassette so I think upping the size of all the rings may be the way to go (to keep it within the 20 band and keep steps relatively equal). It is also a band on so shouldnt be too difficult.

Keef, On the turbo, no only really use the mid and outer ring, but occasionally I let her loose on the road for longer rides as she is the most comfortable bike I have. And I dont think I would have got up some of the hills on the way to Paris without the inner, so will keep the triple for now. Thanks, though.

mercia_man

As you already have an 11-tooth small sprocket, I think your best bet is to buy just outer and middle rings - say 53 and 42. You could replace those without having to remove the chainset. As you have a band on front derailleur it will be easy to move it up enough to clear the 53 outer. I think you'd get away without having to change the inner ring or lengthen the chain - just make sure you don't use big ring/big cog combination. If you change inner ring as well, you will have to remove chainset with the appropriate removal tool and you will lose your bottom gear that you find useful.

I know you would be stretching the mech's 20 tooth limit but manufacturers are in my experience conservative when it comes to giving these figures. As an example, I have run my touring triple with Campag mechs with a 24-tooth difference between outer and inner rings. To ensure optimum shifting make sure you specify, for example, 53 tooth outer and a 42 tooth triple middle (130 BCD five arm) which will have the pick up pins that a 42 inner would lack. Spa Cycles has a good choice. Here's their range of Stronglight rings:

https://www.spacycles.co.uk/m2b0s149p0/ ... tronglight

webboo

At 90 revs a minute 50 x 11 is 32 mph at 100 revs it’s 35 mph. So either everywhere you ride is downhill or you need to be looking in to attempting the hour record.

whyamihere

An alternate idea: Would you consider changing the turbo instead? If you're spinning out 50x11 and it's not providing enough resistance, you could rectify that with even a relatively modest new one. This is assuming that you don't have any way of adjusting the resistance of the trainer you currently have. Even things like tyre pressure and the resistance of the roller (if it's wheel-on) can make a fair difference.

JAMESWRIGHT2004

whyamihere wrote:

An alternate idea: Would you consider changing the turbo instead? If you're spinning out 50x11 and it's not providing enough resistance, you could rectify that with even a relatively modest new one. This is assuming that you don't have any way of adjusting the resistance of the trainer you currently have. Even things like tyre pressure and the resistance of the roller (if it's wheel-on) can make a fair difference.

I am using a Kickr. The main issue comes when I'm using Zwift and it introduces a sightly downward gradient which I want to power through without spinning out. I'm getting old and whikst most of the power is still there my legs are not as fast as they used to be