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Do I need a triple chainring???(4 posts)

Do I need a triple chainring???SmoothGroove
Jul 7, 2002 6:11 PM
Being a racing mountain biker, I'm thinking about buying my first road bike. My current road machine is my mountain bike with 1.5" rubber, I have an extra set of wheels and just swap em' when I hit the pavement. Will I need the triple on the front? I'm in pretty good shape, and my road training rides are around 40-50 miles. Also, how much faster can I expect to go on an actual road bike??

Thanks all
SmoothGroove
where do you live, and what will you ride?laffeaux
Jul 8, 2002 9:01 AM
A triple is very nice if you ride in the mountains; however if you live in the flat lands it's pretty useless. I live in the SF Bay Area, and a triple comes in handy here.

When you ride on the road with your MTB, do you ever use your granny to climb? If so then you need a triple. Even though a road bike rolls faster than a MTB, a road bike double in its lowest gear is harder to turn than a MTB in the middle ring and in the largest cog.

You'll notice that the road bike is faster particularly when it's flat. Your average speed will be higher on a road bike.
Depands on where you intend to ride ...Markus_B
Jul 8, 2002 12:29 PM
Watch yourself: How fast do you climb the hills/mountains in your area?

With a double chainring road crankset (Shimano is available with 53/39, e. g.) and a short cage rear der you cannot use a sprocket with more than 27 teeth.

Assuming a 28" tire being about 2,1 m round and assuming you have to cycle at 60 rounds per minute at least, the result is 39 teeth divided by 27 teeth times 2,1 m/r times 60 r/min times 60 min/h divided by 1000 m/km equals approximately 11 km/h. If you want to ascend slower, consider a triple crankset.

Being in the same situation like you, I chose a double crankset and I have no regrets so far (though they will come for sure if I should ever ride in the Alps).

"tour", a German road bike magazine, claims that triple cranksets in fact offer only 1 or 2 additional gearing ratios (definitely true) and tend to cause chain sucks (sounds reasonable with regard to my MTB experience).

Of course you will be faster, but don't expect too much. If we're not talking about weight weenie MTB vs. lowend road bike, your road bike will wheigh significantly less. It will be more aerodynamic (depends primarily on rider's position). But I do not think it will roll smoother compared to your MTB with slicks.
In getting your first roadbike, go with it.niteschaos
Jul 9, 2002 5:33 AM
If you are just starting out on road, then it won't hurt to have that extra bit. I went from collegiate rowing to cycling, but got a triple just incase because of the mountains in the Greenville,SC region. On my next bike I will most likely get a double with a 25 rear cog because 90% of the inclines I can ride up in a 42/23 gear combo. But I am also planning on doing Assualt on Mt. Mitchell next year so I'm going to get that 25 cog just in case.

Speed difference was really noticeable for me. A road bike on level ground is like riding a mountain bike with slicks down a 2% grade with a tailwind. If it means anything I average 18.8 mph for my non-group and non-lactate threshold workouts. I'm also 6'2" and 188 pounds (I was a heavyweight rower), so not the ideal mountain cyclist build either, but then agian neither is Hincappie.