# An utterly dull chainring question.



## tdr1nka (8 Feb 2008)

I would like to know if changing a 36t chainring to a 38t will make much difference to my ride?

On my MTB I get my most comfortable road speeds on the 38t and 42t rings.

On my trike I'm finding that on the 36t ring I'm having to pedal too fast to get enough speed to get up to the 42t. The leg power is there but wasted on flailing.

Do these ratios necessarily transfer from MTBs to trikes?

Ta.

T x


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## byegad (8 Feb 2008)

Depends on the other ring(s) you have. Also remember you'll raise the bottom gear if its a double.


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## tdr1nka (8 Feb 2008)

The trike runs 3 rings 22, 36 & 42t

I'm happy enough with the 22t for really steep hills but don't otherwise use them, whereas the 36 feels like too much leg spinning for too little power, if that makes any sense? 

I've been able to get onto the 42t ring but only when finishing a fast long road decent and the then the trike fair flies but I just can't reach those speeds coming up from the 36t.

On the MTB I start/warm up on the 38t but spend most of my ride on the 42t.
Could it be the cassette difference? The trike runs 11-28t, but the MTB
is 13-30t.
I'm dead confused.

Thanks again,

T


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## squeaker (9 Feb 2008)

You're confused.....!!!
Your rear cassette has a range of ratios that are far wider than the 36T to 42T jump on the front rings, so just change down at the back when you change up at the front, to get an acceptable step up.
Using a gearing calculator like Sheldon's will give you some idea of what's available.
And IMHO trike and MTB will be similar, but as the trike is heavier, you will probably want smaller gearing steps.
Hope this helps


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## mickle (9 Feb 2008)

Rear wheel size comes into the equation too mind.


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## tdr1nka (10 Feb 2008)

24 of the queens finest inches!
Wheel size BTW.

T x


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## tdr1nka (10 Feb 2008)

p.s.
Finally got to ditch the old 24x2.5 Hook Worm tyre and put a Schwable 24x1.75 Silencio on the back, the trike is a lot zippier! Just need to replace the two fat 16's with skinnys and I'll be flying!


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## LeeW (8 Mar 2008)

I used 32-305 primo comets on the front of my KMX, they seemed to increase my ave speed from about 13mph to 15mph


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