change chainring or cassette
- panosk
- Posts: 84
- Joined: Wed Jan 14, 2015 12:20 pm
change chainring or cassette
Postby panosk » Sun Dec 04, 2016 2:46 pm
The problem is that at the crank length i want, only 53/39 is widely available.
My current set up is 52/36 with 11-28 cassette.
With that, i can go up donna buang without much trouble and use 28 cog at the most difficult parts of the climb.
So my dilemma is:
Should i change chain ring from 39 to 36, or change the cassette to 11-32 ?
- Tim
- Posts: 2948
- Joined: Wed Jul 07, 2010 5:02 pm
- Location: Gippsland Lakes
Re: change chainring or cassette
Postby Tim » Sun Dec 04, 2016 3:19 pm
I tried combining a 52 and 39. It didn't work very well, the chain hung between the two rings and wouldn't change smoothly.
Apparently some other miss-matched combinations do work but I don't know which.
-
- Posts: 644
- Joined: Fri Nov 30, 2012 6:45 pm
Re: change chainring or cassette
Postby BJL » Sun Dec 04, 2016 7:57 pm
Interesting. There's only a 13 tooth gap between 52/39 but a 16 tooth gap between 50/34 & 52/36. Initially, I would have thought that the smaller difference might improve shifting.Tim wrote:The 9000 range of chainrings are designed to work as matched pairs ie. 50/34, 52/36, 52/38(is this new?) and 53/39.
I tried combining a 52 and 39. It didn't work very well, the chain hung between the two rings and wouldn't change smoothly.
Apparently some other miss-matched combinations do work but I don't know which.
I wonder if the angle of travel of the front derailleur is too steep for a 52/39 combo. IE - Derailleur ends up at a 'non-optimal' distance from one of the chainrings depending on position and tuning? I take it the 52/38 would be marginal but acceptable if this was the case.
- Tim
- Posts: 2948
- Joined: Wed Jul 07, 2010 5:02 pm
- Location: Gippsland Lakes
Re: change chainring or cassette
Postby Tim » Sun Dec 04, 2016 9:00 pm
It's more to do with the conical profile/shape of the ramping on the large ring.BJL wrote:I wonder if the angle of travel of the front derailleur is too steep for a 52/39 combo.
With a 52T large ring the bottom of the ramp is designed to drop the chain straight onto the top of a 36 or 38 small ring.
The 39T small ring teeth sit just too high above the bottom of the ramp causing the chain to hang in between the two rings. The side of the chain slides on the edge of the (turning) 39 ring.
Until today I'd not heard of the DA38T small rings paired with a 52T large ring. Might be worth a try one day.
- panosk
- Posts: 84
- Joined: Wed Jan 14, 2015 12:20 pm
Re: change chainring or cassette
Postby panosk » Sun Dec 04, 2016 9:57 pm
- Derny Driver
- Posts: 3039
- Joined: Wed Nov 21, 2012 12:18 pm
- Location: Wollongong
Re: change chainring or cassette
Postby Derny Driver » Sun Dec 04, 2016 10:13 pm
36-28 is pretty close to 39-30
You could put an Ultegra 12-30. Cheapest and best option.
The ramping is different on those front rings. 36-53 will work but not real well.
- panosk
- Posts: 84
- Joined: Wed Jan 14, 2015 12:20 pm
Re: change chainring or cassette
Postby panosk » Mon Dec 05, 2016 12:24 am
12-30 would be ideal but i am afraid there is no 11s cassette with that ratio.Derny Driver wrote:You wouldnt need a 32.
36-28 is pretty close to 39-30
You could put an Ultegra 12-30. Cheapest and best option.
The ramping is different on those front rings. 36-53 will work but not real well.
The closest i have found is 11-30 from sram and shimano 9100, at near 9000 crankset prices.
-
- Posts: 2433
- Joined: Sat Apr 27, 2013 10:28 am
- Contact:
Re: change chainring or cassette
Postby dalai47 » Mon Dec 05, 2016 10:39 am
- Tim
- Posts: 2948
- Joined: Wed Jul 07, 2010 5:02 pm
- Location: Gippsland Lakes
Re: change chainring or cassette
Postby Tim » Mon Dec 05, 2016 10:43 am
110mm.dalai47 wrote:What is the BCD of the 9000 crankset? Will it even take a 36?
The new stuff fits everything from a 34 up to 55.
-
- Posts: 2433
- Joined: Sat Apr 27, 2013 10:28 am
- Contact:
Re: change chainring or cassette
Postby dalai47 » Mon Dec 05, 2016 10:46 am
- jules21
- Posts: 10555
- Joined: Thu Apr 02, 2009 11:14 pm
- Location: deep in the pain cave
Re: change chainring or cassette
Postby jules21 » Tue Dec 06, 2016 10:56 am
- Duck!
- Expert
- Posts: 9876
- Joined: Tue May 21, 2013 8:21 pm
- Location: On The Tools
Re: change chainring or cassette
Postby Duck! » Tue Dec 06, 2016 1:49 pm
The 52T for pairing with 36T is a different ring to the 52T for 38T.Tim wrote: It's more to do with the conical profile/shape of the ramping on the large ring.
With a 52T large ring the bottom of the ramp is designed to drop the chain straight onto the top of a 36 or 38 small ring.
- Tim
- Posts: 2948
- Joined: Wed Jul 07, 2010 5:02 pm
- Location: Gippsland Lakes
Re: change chainring or cassette
Postby Tim » Tue Dec 06, 2016 4:30 pm
I was wondering about that.Duck! wrote:The 52T for pairing with 36T is a different ring to the 52T for 38T.
As I couldn't get a 52/39 pairing to work I wasn't sure how a small ring only one tooth smaller was going to work any better.
So the large ring ramping is different on the 52/36 compared to the 52/38 combination?
Bugger, that means if I wanted to try out a (cheapish) 38 ring I'd have to also buy an horribly expensive different 52 big ring.
Nope.
- Duck!
- Expert
- Posts: 9876
- Joined: Tue May 21, 2013 8:21 pm
- Location: On The Tools
Re: change chainring or cassette
Postby Duck! » Tue Dec 06, 2016 7:01 pm
Return to “Buying a bike / parts”
- General Australian Cycling Topics
- Info / announcements
- Buying a bike / parts
- General Cycling Discussion
- The Bike Shed
- Cycling Health
- Cycling Safety and Advocacy
- Women's Cycling
- Bike & Gear Reviews
- Cycling Trade
- Stolen Bikes
- Bicycle FAQs
- The Market Place
- Member to Member Bike and Gear Sales
- Want to Buy, Group Buy, Swap
- My Bikes or Gear Elsewhere
- Serious Biking
- Audax / Randonneuring
- Retro biking
- Commuting
- MTB
- Recumbents
- Fixed Gear/ Single Speed
- Track
- Electric Bicycles
- Cyclocross and Gravel Grinding
- Dragsters / Lowriders / Cruisers
- Children's Bikes
- Cargo Bikes and Utility Cycling
- Road Racing
- Road Biking
- Training
- Time Trial
- Triathlon
- International and National Tours and Events
- Cycle Touring
- Touring Australia
- Touring Overseas
- Touring Bikes and Equipment
- Australia
- Western Australia
- New South Wales
- Queensland
- South Australia
- Victoria
- ACT
- Tasmania
- Northern Territory
- Country & Regional
Who is online
Users browsing this forum: Google Adsense [Bot]
- All times are UTC+10:00
- Top
- Delete cookies
About the Australian Cycling Forums
The Australian Cycling Forums is a welcoming community where you can ask questions and talk about the type of bikes and cycling topics you like.
Bicycles Network Australia
Forum Information
Connect with BNA
This website uses affiliate links to retail platforms including ebay, amazon, proviz and ribble.