What is your lowest gear and how low is too low. Are new bikes geared too high?

[Fastpedaller]

Easily enough once on the move. Stopping can be a bigger issue.

Derailleur gearing built onto a five speed hub gear.

Easy enough! 229 inches at 90 RPM gives a speed of 61 MPH , and at 30 MPH, I defy anyone to pedal that high a gear at 45 RPM. Is this true?

 

[Fastpedaller]

Indeed but many road riders are not World Tour Pros. Nor do they descend closed road alpine descents as fast as World Tour Pros. Nor do they sprint at 40 mph, like World Tour Pros.

Exactly, most riding over 100 inches don't need it. Even when I descended the Snake Pass to Glossop at about 70 MPH I only had a top gear of mid 90's (I was mostly freewheeling and sitting up to get windbreak when I needed to go slower)

 

[classic33]

Easy enough! 229 inches at 90 RPM gives a speed of 61 MPH , and at 30 MPH, I defy anyone to pedal that high a gear at 45 RPM. Is this true?

Once you get going.
It's true.

 

[roubaixtuesday]

...

I descended the Snake Pass to Glossop at about 70 MPH

That's an incredible speed on that hill. Maybe some calibration needed...

70kph, perhaps.

[Edit: just checked, the KOM on the descent to Glossop is held by Ethan Hayter, 70kph average, max 90kph]

 

[C R]

I have 28:32 in my flat bar bike, which I use for commuting or rough terrain. I rarely need to use the bottom gear.

In my road bike it is 34:34, around here it is fairly flat, so that doesn't see much use either.

 

[Rusty Nails]

My lowest gear is just that little bit higher than I'd like it to be.

Strangely, every bike I've ever had has had the same problem.

 

[Bristolian]

My Allez has a 3x9 setup with 50-39-30 chainrings and 11-32 cassette. I find I can ride mostly without needing the small ring, although there are a couple of hills that would defeat me otherwise. I'm looking to replace the middle ring with a 34T one, which would reduce the lowest gear with middle chainring from 33" to 29", and if that works on my "big" hills then I will convert the bike to 2x.

I did try a 48T big chainring for a few months but it didn't make much difference to my riding, probably due to the poor aerodynamics of my body , so I changed it back again. Also, my average cadence is around 75 so I'm never gonna bother even a mediocre club rider (these days)

 

[Fastpedaller]

...


That's an incredible speed on that hill. Maybe some calibration needed...

70kph, perhaps.

[Edit: just checked, the KOM on the descent to Glossop is held by Ethan Hayter, 70kph average, max 90kph]

The speedo gave out at 67MPH - I had no reason to question its accuracy, having used it for many time trials. In fact I still use it on my 'most regular' bike.

 

[roubaixtuesday]

The speedo gave out at 67MPH - I had no reason to question its accuracy, having used it for many time trials. In fact I still use it on my 'most regular' bike.

It's definitely wrong! No way Snake is steep enough for that speed, you're 10 mph *faster* than the pro who holds the KOM!

 

[lenfield]

Easy enough! 229 inches at 90 RPM gives a speed of 61 MPH , and at 30 MPH, I defy anyone to pedal that high a gear at 45 RPM. Is this true?

Yes.

inches per hour = radius * pi * rpm * 60 mins
229 * 3.142 * 90 * 60 = 3885397.2

mph = inches per hour / inches per mile
3885397.2 / 63,360 = 61.32

 

[a.twiddler]

On my 2007 2-speed Brompton i did the DIY conversion to 3 speed, at the same time changing the bb to JIS and some Spa 160mm cranks to be able to use a 10-speed chain and sprockets. it worked well, and the next step was to fit a 36T inner ring to go with the 52T outer. Fold fine as long as it's in the big ring - if in the small ring, there would be too much chain slack. I used one of the 40mm clamps from Ebay to fit a 'braze-on' type Shimano front derailleur, and it works great - the clamp means there is enough adjustment to get it perfect. I used 1mm flexible plastic 'double glazing' shims to pack out the 38mm seat tube to 40mm for the clamp, and suggest inner tube of similar will give problems because it's not rigid and will relax as well under load. I like close ratio, so used 12,13,15 sprockets giving a range from 39 -69 inches.
As you are A Twiddler, that would probably suit you as well

Current range is 24.66 -77.6". Greasy finger works for now, but the main concern I suppose would be finding a FD that will cope with the 22T jump between the front rings if I were to take the plunge.

 

[HLaB]

My 2 road bikes have a 36x28 lowest gear.
My TT bike (indoor trainer at the moment) has 39x25.
The gravel bike has a 31x32.

 

[Vapin' Joe]

One point to always remember -

No one ever had to walk down a hill because their gears were too low.

 

[Alex321]

It will give you 27 mph at 90 rpm. Just how fast on the flat do many road cyclists go?

What has "the flat" got to do with it?

Many would like to keep pedaling on gentle downhills, where they might be getting into the low 30's.

I never use the highest gear on the flat, but I often do on clear and open downhills. And that is with a 122 inch top gear.

 

[Sharky]

Going back 50 years or so, when I was just getting TT's etc, I had one bike that did all.
A 54/44 on the front and a 14-18 block. Had few problems with hills but in the office season, I had a special 18-20 block made up. I couldn't believe how easy it was on the hills.

Couldn't live with that now, although my 68" SS gets me up most local hills.