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Do I need a bigger Chainring?

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#21 ·
Keep in mind that a larger chainring requires a longer chain, usually a new chain.

If you get chain skipping it is possible that there is a problem with the chain, like a slight kink that you can only tell with careful examination.

But this problem sounds like a freehub. I would open it and clean just for fun.
 
Discussion starter · #22 ·
CrozCountry said:
Keep in mind that a larger chainring requires a longer chain, usually a new chain.

If you get chain skipping it is possible that there is a problem with the chain, like a slight kink that you can only tell with careful examination.

But this problem sounds like a freehub. I would open it and clean just for fun.
Click to expand...
Free hub is brand new.
 
#23 ·
Stahr_Nut said:
True Story. Not long ago I was riding with a friend who was complaining about how since he recently had his bike in for service at his local shop he has constantly been dropping his chain. I looked down at his Shimano RD and flipped the lever and told him, problem solved. :LOL:
Click to expand...
I had a similar experience. But instead of telling him I flipped the lever, I made Tibetan Monk chant sounds, rang my bike bell a few times, threw a handful of dirt on his bike, and told him it was fixed.
 
#30 ·
Mookistar said:
So looking at my options, the biggest chainring is 34t. Do I need to change the whole crankset to go bigger?

I have the Shimano 32t SLX SM-CRM75 Single chainring for SLX M7100 / M713 at present…
Click to expand...
You should not need a new crank to fit a bigger chainring.
FYI
32x11, 13, 15, 17, 19 = 2.82, 2.46, 1.88, 1.68
34x11, 13, 15, 17, 19 = 3.09, 2.27, 2.00, 1.79 (on my trails I spend a lot of time in 34x22 = 1.55, or 36x21 = 1.71)
Final drive depends on your wheel/tire size (for total gear inches)

So the 34T will up your range by about 1-1/2 cogs in the back. You'll spend more time closer to the middle of the cassette.

-F
 
Discussion starter · #31 ·
The reason I thought I needed a new crank is because the chainring is direct mount and Shimano only make 2 sizes.
Perhaps I’ll give 34 a go to see if it leaves me short in the higher gears should I change terrain.
 
#35 ·
Sorry to be obtuse, but I'm still baffled that you ONLY use the 3 smallest cogs. If we use a common 90 rpm cadence, a tire diameter of 744mm , and plug 10T, 12T, and 14T in as the hardest 3 gears of a 10-51 SLX cassette, we get 25mph, 21mph, and 18mph? Really? Many of us are plenty strong but need some lighter gearing than 14T/18mph even on the road. Or are you pedaling with a much higher force/lower cadence which could lead to some nasty sounds out back occasionally, especially if you're trying to shift while pedaling super hard at 50rpm?

EDIT: to be clear, you may still want a 34T or larger ring to avoid spinning out on downhills, but wonder if you might try a different approach on these undulating grass hills that are producing the symptoms described in the OP.
 
#36 ·
Standing on the pedals usually doesn't produce 90rpm. I personally only stand occasionally, but my brother stands on the cranks all the time. He put his seat in the car so his Thudbuster wouldn't get stolen. His wife drove off with it and he rode 10 miles home with no saddle. Short rides he doesn't bother to put it on the bike.
He runs a 48x11t top gear on 700x52mm tires. NYC Commuter. 175mm cranks too. Some people like to ride that way.
 
Discussion starter · #37 ·
Clyde Ride said:
Sorry to be obtuse, but I'm still baffled that you ONLY use the 3 smallest cogs. If we use a common 90 rpm cadence, a tire diameter of 744mm , and plug 10T, 12T, and 14T in as the hardest 3 gears of a 10-51 SLX cassette, we get 25mph, 21mph, and 18mph? Really? Many of us are plenty strong but need some lighter gearing than 14T/18mph even on the road. Or are you pedaling with a much higher force/lower cadence which could lead to some nasty sounds out back occasionally, especially if you're trying to shift while pedaling super hard at 50rpm?

EDIT: to be clear, you may still want a 34T or larger ring to avoid spinning out on downhills, but wonder if you might try a different approach on these undulating grass hills that are producing the symptoms described in the OP.
Click to expand...
I don't quite know how to answer this. I'm certainly no fitter than anyone on here but can only ride what is ahead and under me. I'm trying to maintain a pace and find I literally never need to move out of those 3 gears. My ride is mainly flat so i just pedal to the route.
It's a short route so I'm pushing but don't really know what else to say.
 
Discussion starter · #38 · (Edited)
Clyde Ride said:
Sorry to be obtuse, but I'm still baffled that you ONLY use the 3 smallest cogs. If we use a common 90 rpm cadence, a tire diameter of 744mm , and plug 10T, 12T, and 14T in as the hardest 3 gears of a 10-51 SLX cassette, we get 25mph, 21mph, and 18mph? Really? Many of us are plenty strong but need some lighter gearing than 14T/18mph even on the road. Or are you pedaling with a much higher force/lower cadence which could lead to some nasty sounds out back occasionally, especially if you're trying to shift while pedaling super hard at 50rpm?

EDIT: to be clear, you may still want a 34T or larger ring to avoid spinning out on downhills, but wonder if you might try a different approach on these undulating grass hills that are producing the symptoms described in the OP.
Click to expand...
William P said:
Standing on the pedals usually doesn't produce 90rpm. I personally only stand occasionally, but my brother stands on the cranks all the time. He put his seat in the car so his Thudbuster wouldn't get stolen. His wife drove off with it and he rode 10 miles home with no saddle. Short rides he doesn't bother to put it on the bike.
He runs a 48x11t top gear on 700x52mm tires. NYC Commuter. 175mm cranks too. Some people like to ride that way.
Click to expand...
THANK YOU. THANK YOU. THANK YOU.

These two posts get me thinking about my riding style and today I changed things up.
Up to now my policy has been to get into the highest gear as I can and ‘push’. I figured fast spinning legs = wasted energy.
Today I stayed in lower gears but increased my cadence, only changing up when it felt like the ‘effort’ to pedal remained the same.

I also stayed in the saddle for almost the whole ride. Again I believed getting up and pushing was the key to fast riding.

I just took 16 seconds off my personal best for a route I’ve been riding for 3 months.
And best of all it felt easy!!

So thank you for changing my perspective. I’m well happy this morning!!
 
#39 ·
Now refine your spin. Raise the back leg on the upstroke, don't make the other leg push it up. Then start the power stroke early across the top. Moving the saddle back a little may help. Then sweep across the bottom.
The ankles are involved in this activating the calf muscles. Don't be surprised if this results in you shifting up a gear or 2.
You'll know your doing it right if you still need a bigger chain ring.
 
Discussion starter · #40 ·
William P said:
Now refine your spin. Raise the back leg on the upstroke, don't make the other leg push it up. Then start the power stroke early across the top. Moving the saddle back a little may help. Then sweep across the bottom.
The ankles are involved in this activating the calf muscles. Don't be surprised if this results in you shifting up a gear or 2.
You'll know your doing it right if you still need a bigger chain ring.
Click to expand...
Will do! Thank you!
 
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