Chainsets - compact.
dinkdankdo10
Posts: 180
Hi all.
Wonder if a few could help me out with a couple of questions.
My new bike has a standard chain set at 53/39. Lovely, but I live in the peaks and use the full range on my compact currently on my other bike with a 34/50 set up so I would like to drop the 39 to 34 on the new bike.
Couple of Qs. My current bottom bracket is BB386 Evo bottom bracket standard using a FSA SL-K chainset. I have seen Planet X are doing a deal on the same chainset with a 34/50 set up but with a different bottom bracket.
Could I use the bottom bracket that is already on the new bike and simply switch the chainset (minus bb) ?
If not i hear I could drop the cassette on the new bike to a smaller one and keep the 53/39 chainset that may give me the same as a 34/50 chainset. Is this true and what size should I go for ?
Many thanks
Wonder if a few could help me out with a couple of questions.
My new bike has a standard chain set at 53/39. Lovely, but I live in the peaks and use the full range on my compact currently on my other bike with a 34/50 set up so I would like to drop the 39 to 34 on the new bike.
Couple of Qs. My current bottom bracket is BB386 Evo bottom bracket standard using a FSA SL-K chainset. I have seen Planet X are doing a deal on the same chainset with a 34/50 set up but with a different bottom bracket.
Could I use the bottom bracket that is already on the new bike and simply switch the chainset (minus bb) ?
If not i hear I could drop the cassette on the new bike to a smaller one and keep the 53/39 chainset that may give me the same as a 34/50 chainset. Is this true and what size should I go for ?
Many thanks
0
Comments
-
Doubt it will work, it is too big a difference 53/34, usually 16 tooth difference is about the max between them. Rear cassette can be changed so biggest cog has more teeth, depends what you're running now.0
-
Sorry it would be changing from 53/39 to a 50/34. Would I be able to use the same bottom bracket ?
Thanks0 -
Fit a 30 or 32 tooth rear cassette
I have a 53/39 with a 12-30 Ultegra cassette and it got me over several lakeland passes of 25% gradient in 30 degree heat recently
And I am 16 stone and pushing 50.0 -
a 39 chainwheel with a 30 tooth cassette gives a ratio of about 1.30, which is similar to a 34 chainwheel with 26 tooth cassette.
New ultegra derailleur (6700A) is designed to take a 30 tooth cassette.
Or fit SRAM wifli (long cage derailleur and 32 tooth cassette ) if you have sram shifters
Much cheaper than changing the crankset in any event0 -
^ as above0
-
In response to question about retaining BB and simply swapping cranks - you can either use another BB386 or any model of 24mm spindle crank. You can't use BB30 as the spindle is too short.Make mine an Italian, with Campagnolo on the side..0
-
Thanks all. I have ultegra di2 and just read that will cover up to 30t. At know a website I check the ratios out etc ?
Thanks all0 -
http://home.earthlink.net/~mike.sherman/shift.htmldinkdankdo10 wrote:Thanks all. I have ultegra di2 and just read that will cover up to 30t. At know a website I check the ratios out etc ?
Thanks all0 -
Cranks or chainrings will be interchangeable. You'll need to drop the front derailleur down by a few mm and take a few links out of the chain, but otherwise, will be relatively straightforward.0
-
Swap the chainset rather than the cassette, put a 30t cassette on and your shifting will be like a bag of spanners compared to a 25t.0
-
Bozman wrote:Swap the chainset rather than the cassette, put a 30t cassette on and your shifting will be like a bag of spanners compared to a 25t.
That's funny. I've been in the Alps running an 11-29 and the shifting has been absolutely fine. Maybe you did something wrong.
Faster than a tent.......0 -
Thanks everyone. The chainset is staying as is and switching to a 11-28 cassette.0
-
Rolf F wrote:Bozman wrote:Swap the chainset rather than the cassette, put a 30t cassette on and your shifting will be like a bag of spanners compared to a 25t.
That's funny. I've been in the Alps running an 11-29 and the shifting has been absolutely fine. Maybe you did something wrong.
I have a 12-30 over Lakeland passes and that too has been perfect.
If you have a derailleur with too short a capacity then shifting will be clunky, but fitting a derailleur to match the cassette will result in perfect shifting even with an 11-32 cassette.0 -
dinkdankdo10 wrote:Hi all.
Wonder if a few could help me out with a couple of questions.
My new bike has a standard chain set at 53/39. Lovely, but I live in the peaks and use the full range on my compact currently on my other bike with a 34/50 set up so I would like to drop the 39 to 34 on the new bike.
Couple of Qs. My current bottom bracket is BB386 Evo bottom bracket standard using a FSA SL-K chainset. I have seen Planet X are doing a deal on the same chainset with a 34/50 set up but with a different bottom bracket.
Could I use the bottom bracket that is already on the new bike and simply switch the chainset (minus bb) ?
If not i hear I could drop the cassette on the new bike to a smaller one and keep the 53/39 chainset that may give me the same as a 34/50 chainset. Is this true and what size should I go for ?
Many thanks
You cannot use the same bottom bracket if you buy the FSA SL-K compact crankset which is currently on sale at Planet-X.
Reason is that the spindle size of this particular crankset is different from the spindle size of he BB386 standard, and as such the Crankset would not fit in the new BB.
You can go as as wide as 11-30t cassette on Ultegra Di12 rear mech and this would indeed give you an equivalent range with the standard crankset (to using a compact with standard range cassette), but I would not do this because the gaps would be too wide for me to enjoy the shifting.
If it was me, I would save up and buy a Compact Crankset which would fit the current BB standard of the frame.
You will enjoy your ride much more in the long term than fudging it.0
