Gear Ratios explained

rdkaz

New Member
Can anyone explain the riding effect of the gear ratio differences between these two:
Front: 36, Rear: 11 - 34 (11 speed)
Front: 44, Rear: 10 -42 (9 speed)

Thanks
 

J.R.

Well-Known Member
Can anyone explain the riding effect of the gear ratio differences between these two:
Front: 36, Rear: 11 - 34 (11 speed)
Front: 44, Rear: 10 -42 (9 speed)

Thanks
Explaining the riding effect of different gear ratios is a really BIG, BIG question! With different effect for every answered question:
  • Your weight
  • Your strength
  • Your endurance
  • How far you'll be riding in a day
  • How hard you're willing to push
  • How much baggage you'll be carrying
  • The steepness of the terrain
  • The nature of the road surface
  • What kind of riding (urban stop and go/rural/touring/racing...)
  • How much effort you are willing to put into maintaining your bicycle
Bullet points copied from Sheldon Brown.

You should start here in my opinion: https://www.sheldonbrown.com/gear-theory.html

Then maybe: https://www.sheldonbrown.com/gear-calc.html

There's no way to answer the riding effect you will have with the two gear-sets you list. You'll need to do the work and learn and Sheldon Brown is the best place to start. You may also go through some parts with trial and error to achieve what you want. If that's not acceptable, you could always try a professional bike fitter.

Good luck!
 

Ann M.

Well-Known Member
Excellent links, @J.R. ! Gear ratios matter :). For a simplistic view, the larger the size of the chainring on the front, the higher your top speed but harder to climb, were the rear clusters the same. Also, very small gears in the rear (10 or 11 tooth) will give you higher speed on flat ground if your using the same front gear. A lot of ebikes theoretically designed for an average, non-racing type rider, include the 34T or 42T cog to help with the hills but not easy to shift into since its a big jump from the previous gear.

A common complaint we would get at our shop from stronger riders was that the front cog (when it's just a single front gear) was too small. They would out pedal all of the top gearing with motor assist and feel limited that their human power wasn't getting them down the road a little faster! Gearing is really a purpose focused set of choices with a rider's ability also part of the equation.
 

MLB

Well-Known Member
Real simplistic: The numbers you give used with the proper formula yields a total range of gearing, from lowest to highest. As a range of numbers, say 20-115 (triple ring front). For climbing the hardest hills, the lower the number the easier the peddling. The higher number is the top gear, and will equate to the fastest top speed IF you are strong enough to pull that gear to maximum cadence (peddle speed).
THEN specifically, a larger front ring = higher top speed = hard to push, takes more strength to turn. Larger = faster
On the rear it's the opposite effect. There a smaller ring = higher top speed/harder to push.

So in your example bike 2 with the 44 front is a much taller gear than a 36t. Significantly so. Much better for road work, top end speed. Not as good for hills and bad for offroad. (in general)
BUT then on the rear, bike 2 has a lower low gear with the 42 vs 34 (bigger = lower =easier to turn, for climbing). But I don't "think" it would make up for the larger range in front.
Using a gearing calculator (Sheldon brown and others) will give you the exact numbers but I would "think" that bike 2 would make you happier at faster speeds. Bike 1 on hills. But not sure how much.. ;)
 

MLB

Well-Known Member
Gearing is a discussion that I've been thinking needs to start being a major topic of interest.
Once you've got an ebike, tuning it to what you use it for is the next logical step.
My Haibike is very difficult to pedal beyond the 20mph assist because it's geared too low (for offroad work). Changing to a larger front ring would up the total overall gearing range and make it possible to peddle and add speed to the top of the E limit, like I prefer. My Stromer (no offroad low gearing) was easy to peddle 3-4mph faster than the boosted speed (28!) and though that was too fast (JMO!) it feels more natural and fulfilling (athletically) as you can still 'blow it out" (wind sprints, max effort for short spurts) and get actual speed out of it.

In addition, I've actually felt the torque of the bosche mid drive maybe 4 times in the past year. It's flat where I live and even the steepest hills dont' test a decent E bike. The Stromer and my Falco equipped trike are both way faster, even up hills. The ONLY time the Bosch shows it's real bones is on some really steep, very short climbs out of drainage ditch banks and such and THEN it was like "Wow, that was almost motorcycle like pulling" (compared to hub motor with street gearing).

Often in discussions of mid drives vs hubs or whatever, gearing is totally overlooked in the what is faster, stronger, discussions.
It's as much a factor as the motor used, or configuration. And lots of Ebike can be changed to suit much more fully with a simple gear change. ;)
 

rdkaz

New Member
Thank you all for your excellent replies.

The quoted bullet points are helpful considerations. I recently retired; and am purchasing my 1st full suspension e-bike, for a mixture of mountain, forest service, and paved road riding. The primary riding will be on hilly mountain forest service unpaved dirt roads. I am a recreational (non-competitive) rider; with questionable knees; but otherwise in good physical condition. I am 5-8; and weight 190 lbs.

I am considering only speed pedelecs; to enable higher speeds on flat terrain; but don't want to walk the bike up the hills.
I was not sure which gearing would suit my riding. I am considering the 2016 Focus Throns; and Haibike Full Seven "S" series.

The simplistic and real simplistic explanations were very helpful. It appears that either would work for my riding style.
Which would work best; considering both are speed pedelecs ?

Thanks Again!
 

MLB

Well-Known Member
For any offroad, especially hilly(!) you probably can't get too low with the gearing. Factor in gimpy knees and it's a no brainer, you need LOW gearing!! I would expect that if you gear your bike to suit the climbing, it probably won't be able to add speed with peddling above the 28mph mark.
Choose the bike you like the best, gearing is easy and comparatively cheap to change.
AND if being used aggressively offroad and climbing, the stockers won't last long anyway! (important to know and plan for)
I love my FS RX for what it's worth, Focus is a very good brand too. Fabulous offroad and very good onroad. I sold my 28mph Stromer and run street tires on the 20mph RX, the suspension is THAT nice. The new Yamaha motored Hai's with it's extra torque and the double front rings is an outright billy goat apparently. You just keep climbing if the peddles are moving.
Seems like the hot ticket for real hills. JMO
 
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