bike question relating to chain rings/crank system

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2005-02-16 3:34 PM

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Subject: bike question relating to chain rings/crank system

Ok, after reading several articles on parktool and other biking sites, I have a couple of questions relating to what I think is the chain rings of the crank system, which they didn't spell out clearly for a non-biking person.

I have two mountain bikes and noticed that on my older one, it has a larger diameter on the largest chain ring in the crank system, than on my newer mountain bike. That said, the older one I feel gives me better pedaling because I can constantly pedal without having to pause. What I mean by that is, on the newer bike, I have to pedal, then the bike is almost going to fast and so I have to pause for a second on pedaling for my bike to slow down for a second, for me to pedal (hope this makes sense). As if I want to go faster but the stupid pedaling system is too slow for the speed of the bike.

I only noticed this because I started to ride on the flat rode (practicing for the tri) instead of mountains. 

So, my question is, do I have to change the diameter of the largest front chain ring to fix this problem on my newer mountain bike, or is it the pedal stem length or the actual size of the bike because it's two different sized bikes?

Does anybody else have this problem, the pedaling too fast for the bike?

(assume I'm not going to buy a road or tri bike as my solution to this problem).



Edited by auto208562 2005-02-16 3:36 PM

2005-02-16 3:40 PM
in reply to: #118179

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Elite
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Subject: RE: bike question relating to chain rings/crank system
auto208562 - 2005-02-16 2:34 PM

Ok, after reading several articles on parktool and other biking sites, I have a couple of questions relating to what I think is the chain rings of the crank system, which they didn't spell out clearly for a non-biking person.

I have two mountain bikes and noticed that on my older one, it has a larger diameter on the largest chain ring in the crank system, than on my newer mountain bike. That said, the older one I feel gives me better pedaling because I can constantly pedal without having to pause. What I mean by that is, on the newer bike, I have to pedal, then the bike is almost going to fast and so I have to pause for a second on pedaling for my bike to slow down for a second, for me to pedal (hope this makes sense). As if I want to go faster but the stupid pedaling system is too slow for the speed of the bike.

I only noticed this because I started to ride on the flat rode (practicing for the tri) instead of mountains. 

So, my question is, do I have to change the diameter of the largest front chain ring to fix this problem on my newer mountain bike, or is it the pedal stem length or the actual size of the bike because it's two different sized bikes?

Does anybody else have this problem, the pedaling too fast for the bike?

sounds like a gearing issue.  your old MTB has more teeth in the big chainring than your new MTB so your old MTB has a "higher" gear causing you to pedal less RPM at the same speed compared to the new MTB chainring.

but remember, optimal cadence for tri racing is typically >90RPM so before you go changing anything check out your cadence



Edited by Steve- 2005-02-16 3:41 PM
2005-02-16 3:42 PM
in reply to: #118184

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Subject: RE: bike question relating to chain rings/crank system

So, do I have to replace the whole crank system on the newer bike if it's not related to cadence?

sounds like a gearing issue.  your old MTB has more teeth in the big chainring than your new MTB so your old MTB has a "higher" gear causing you to pedal less RPM at the same speed compared to the new MTB chainring.

but remember, optimal cadence for tri racing is typically >90RPM so before you go changing anything check out your cadence



Edited by auto208562 2005-02-16 3:43 PM
2005-02-16 3:45 PM
in reply to: #118179

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Subject: RE: bike question relating to chain rings/crank system

What color is you bike? If it's not RED  then the problem is it's too slow.

Any idea what cadence you're pedaling at? Sounds like you're "spinning out" and your gears are too small for use on the road. You're not able to tap all of your power, thus are going slower than you can.

Count the teeth on both big chain rings, also count the teeth on all your cogs in the back. That will tell you the different sizes of your gears, and will telll you if you will benefit from changing the cogs/cassette (cheaper) or if you have to change the chainring (more expensive).

2005-02-16 3:46 PM
in reply to: #118179

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Elite
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Subject: RE: bike question relating to chain rings/crank system

Before I answer that, answer me this:

1.  what do you want to use your new MTB for? (type of races, type of terrain)

2.  how many teeth does your smallest cog in the rear and largest cog in the rear have on your new MTB?

3.  how many teeth does your smallest cog in the rear and largest cog in the rear have on your old MTB?

4.  how many teeth does your largest chainring have on your new MTB?

5.  how many teeth does your largest chainring have on your old MTB?

2005-02-16 3:47 PM
in reply to: #118190

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Resident Curmudgeon
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Subject: RE: bike question relating to chain rings/crank system
What, is there an echo in here?

2005-02-16 3:47 PM
in reply to: #118188

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Pro
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Subject: RE: bike question relating to chain rings/crank system

Ironically, the older mountain bike with the larger diameter and which is faster, is red.  The newer mountain bike is slower and NOT red.

the bear - 2005-02-16 12:45 PM

What color is you bike? If it's not RED  then the problem is it's too slow.

2005-02-16 4:13 PM
in reply to: #118191

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Elite
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Subject: RE: bike question relating to chain rings/crank system

the bear - 2005-02-16 2:47 PM What, is there an echo in here?

No, just a slow computer connection...(check the post times)

2005-02-16 7:14 PM
in reply to: #118179

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Subject: RE: bike question relating to chain rings/crank system
yo bear, you like cajon fried chicken? it is spicy but f-ing good. Don't hate on the dial-up cats. In most of Philly we get free high speed internet through the colleges. Peace, and keep chow down on the cajon.
Jdog
2005-02-17 1:56 AM
in reply to: #118179

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Subject: RE: bike question relating to chain rings/crank system

I just counted the teeth and there are definitely more in the front, and same # in the back. 

2005-02-18 11:21 AM
in reply to: #118179

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Subject: RE: bike question relating to chain rings/crank system

Just to let you know, I bought a crank puller and switched the pedal part (with the chain rings) on the two bikes, but it was a bigger hassle than anticipated.  Because, not really anticipating it, I had to adjust the dumb front derailer height, which now covers one of my holes that is part of on of the water bottle cages (redering that cage useless with only one hole), and thus the actual derailer.

I guess I learned a whole bunch about my stupid bikes.

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