My friend has suggested to me that my recent bike leg at Vineman could have been faster if I used a bigger chain ring with my 650 wheels…Current set up 53x11, could this be true. He suggested a 55x11 could have been a better gear set up…seeing that the wheels are smaller…2:46 bike leg…thx Sam
Were you spinning your gears out? 53x11 is quite a bit of gear, even on 650’s.
I would say yes on the down hills…but not on the flats…I cant push a gear that big on a straight for 2;40+ hrs…He says I should swap out the gear in the off season//he also says that the gear I was pushing was like pushing a 51 chainring with the 650 wheels…He is a roadie ///sometimes he helps me with my training ,and is very helpful at times but he dosent swim and then get of the bike to run///
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Hmm, I guess it just depends on how fast you feel the need to go down hill. Take the opinion of roadies with a grain of salt; nobody ever complains of being too fresh for the run.
Yes, bigger is always better. Just ask the ladies.
has anybody else changed to a bigger chainring because of 650 wheels?..If so did it help out ?
Another thing to consider is shifting. I’m not sure the 39 to 55 jump would be smooth. Your little ring might have to be a 42.
Perhaps someone has tried it?
yeah, i used to use a 56-tooth chainring on my old bike, and a pretty little cassette. this was on a steep-angled 650 bike, and i was very happy with it. i also have big legs and considered myself (at the time, at least) more of a ‘power’ rider.
and yeah, the little ring was a 42, i think. shifting was ultegra 8-speed STI - no problems.
-mike
How was your chainline in your normal cruising gears? If you’re riding the 53-12 on the flats, then yes, you could improve that by jumping up the chainring size.
I assume he recommended the bigger chainring so you didn’t spin out on the downhills? If you have ever ridden a hilly course with a power meter you would probably buy a smaller chainring instead of a larger one for hilly races. A power meter will show you how much power it takes to go faster at high speeds and I can tell you the output is huge and your speed increase is small. You would we much better served to tuck in or soft pedal past 30 mph and use your energy on the uphills at slower speeds when it will make a much bigger difference in speed.
Now if you can roll the 53x11 for long periods on the flat at 85+ rpm then you are a stud and maybe a bigger chainring might help. I suspect that most people would be better of with 50x12s or less so they don’t overwork on the downhills. I raced the rolling course at duathlon nationals by softpedaling the downhills and working the uphills and it was comical to see how hard people worked to pass me going down the hill only to have me re-pass them easily going up.
Chad
Spin faster. I have experimented throughout the years with big ring sizes from 53-56 - and have settled on the 53. You should be able to pedal into the 40mph category downhill without “spinning out”. If not, you could use some cadence training. A 53-11 is a hot combo on a 650c wheeled bike. Only on a flat course with a very strong tailwind would I ever wish for a 54 or 55.
Someone mentioned shifter performance. Indeed, it is a factor and most larger rings are not ramped/pinned (some are). It is a big jump for a chain to fall from a 55 to a 42, providing lots of room for error.
Larger big rings will prove a limiting factor on shifting range in the rear, too.
A few extra seconds of downhill advantage per race? Only if you’re consistently running into 40mph + downhills, IMO. Otherwise you shouldn’t be spinning out. Not worth the other sacrifices if you ask me.
My opinion, too:
I’m 6-3 with very long legs, 180mm cranks but on a 700c frame. I ride 54-42’s using Rotor Cranks. One of the big differences with this setup compared to the others I’ve used, 53-44, is that my cadence has slowed, which has helped lower my HR and increase my speed. Its not just downhills and uphills you need to watch for the optimum chainring size. I live on the flat east coast of Florida and the 54-42 works very well.
I believe a 55 or 56x42 on 650c wheels is about equal to a standard 53/39 on 700s. I wouldn’t worry about it, though, if you’re not having problems with your current setup.