Moving to more teeth on a single chain ring

[michaelmac]

Hi
I think what I want to do is move from a 46 t a 52 t chainring. The reason for this is because at a normal 60 revolutions per minute, I'm only doing about 12 miles an hour. So, I think ,,,, emphasis on think... That adding more teeth to my chain ring will give me more high-end speed at the same revolutions in the same rear gear. The bike has a single front crank with eight years in the back
This modification would be to a recumbent Terratrike rambler E VO ... Also if I'm thinking correctly it will make going up hills harder in other words I will be able to go faster but getting started and getting up hills will be harder, more effort, am I thinking about this correctly?. But, this is an electric bike so how hard is hard.
my other problem with my new Tara trike is adjusting my Rocky Mount swing away bike rack. It still needs to be able to haul my wife's bike as well as the recumbent. Basically, what I'm thinking about is simply making a platform for the back to wheel ..... Any ideas on this would be welcome
thanks in advance for your help
Michael

 

[6zfshdb]

Depending on your 8 speed rear cassette, another possibility would be to swap it with one that has fewer teeth on the high speed (Smallest) sprocket. That way you could maintain your lower gear hill climbing capability while still increasing your 60 RPM cruising speed. This of course depends on the existence of such a cassette that will fit your bike.

 

[Bruce Arnold]

It's always a trade-off when we make modifications, isn't it?

The Juiced Bikes Crosscurrent and Ripcurrent models are designed for speed rather than low-end torque. They come standard with a 52T chain ring. Since it is an ebike, with plenty of power assist, I've never used the lowest 2 gears for anything but the steepest hills. Getting away from stoplights on 3rd gear is just fine. There are guys on the Juiced Bikes forum with lots of experience with pulling long hills that could speak to this aspect. I'm not trying to sell you a Juiced product, just that we've got experience with a 52T chain ring.

 

[harryS]

Nice bike. This one? Bosch motor up front.

Rambler E.V.O. - Bosch - TerraTrike

Rambler E.V.O. - Bosch - TerraTrike

www.terratrike.com

You already got a 10 speed cassette in the rear with 11T on the smallest gear.

This calculator says, yep, 60 cadence should be around 14 mph with your 46T. You'll do 16 with 52T.

Bicycle Gear Speed Cadence Table | BikeCalc

Calculate cycling speeds at a specified cadence given chainring, sprocket, tire and wheel sizes.

www.bikecalc.com

 

[PaD]

Nice bike. This one? Bosch motor up front.

Rambler E.V.O. - Bosch - TerraTrike

Rambler E.V.O. - Bosch - TerraTrike

www.terratrike.com

You already got a 10 speed cassette in the rear with 11T on the smallest gear.

This calculator says, yep, 60 cadence should be around 14 mph with your 46T. You'll do 16 with 52T.

Bicycle Gear Speed Cadence Table | BikeCalc

Calculate cycling speeds at a specified cadence given chainring, sprocket, tire and wheel sizes.

www.bikecalc.com

I thiink the OP tried to tell us he has 8 gears.

 

[michaelmac]

Yep ,,, 8 speed is what I have it was a demo model . Maybe they moved to 10 to get some more speed .
Thanks
m

 

[michaelmac]

Sorry ,, I thought I had proofed my post. It's Gears not years ,,,,so much for word recognition

 

[PaD]

Could be interesting to know how many teeth there are on your smallest cogwheel ( and also the kargest)
I get the impression the 8 speed cassette was meant to be paired to a dual or triple crankwheel setup.

 

[harryS]

Then you have more room for improvement if it's 8 speed. Your fast gear on that was probably only 12T so you could add 11T for speed, and a bigger 10th gear to get your climbing capability back on hills..

 

[steve marino]

Yep, a bigger front cog will give you more top speed at the same crank revolutions. I wouldn't worry about hills since you have 8 speeds on the back. Just drop it in to one of the lower gogs for those. Might want to do some simple online calculator calculations on the difference in MPH if you go from 48 to 52 to see if that will be enough. My guess is you might want a few more teeth on the front to get a noticeable difference, but that might depend on whether you live in Florida (flat as a billiard table) or in San Francisco (a real knee killer town for bikes).

 

[michaelmac]

HI
I kind of wondered about the 52t year myself. But, I have a clue how to figure that and the calculator that HarryS posted was way the on me. When I tried was a simple percentage which told me that I would gain about 2 miles an hour. I'm not sure that that's enough to go through the trouble.
52t is the largest chainring that I have found out they are. If you have a source for a 104 bcd with more teeth could you pass a along. I'm going to head out to the garage and see about counting the teeth on the largest and smallest cogs.
Thanks for your message
Michael

 

[michaelmac]

OK ,,, the big wheel is 32t and the small one is 12t ,,, The set may be something like B2
Thanks
m

 

[PaD]

I think you’re right about thr 2mph going from 46 to 52 crankwheel.
Is there anything stopping you from increasing cadence just little? Going from 60 to 70 should reward you with another 2- 2.5mph.

 

[6zfshdb]

It appears from the specs on your trike the 8 speed cassette is a Microshift 12-32T. Microshift also makes an 11-32T which may be a direct replacement:

Products | microSHIFT

microSHIFT components: shifters, derailleurs, cassettes

www.microshift.com

Amazon has one for around $18:

Amazon.com

I would check the fit first before ordering. Of course you could always return it if it doesn't work.

Reducing the small cog from 12 to 11 teeth should give you the speed increase you're looking for. If not, you could also add the 52 tooth chainring.

 

[harryS]

Never realized recumbents were so limited on speed, but of course we have three bikes with 20" wheels and all top out around 18-20 mph with pedaling. Fast enough on them.

 

[PaD]

Never realized recumbents were so limited on speed, but of course we have three bikes with 20" wheels and all top out around 18-20 mph with pedaling. Fast enough on them.

What cadence do you need to go 18-20mph on these bikes?
There are e-bikes with full size wheels that will not reach 20mph if you restrict yourself to cadence 60.
I’m criticing the OP for wanting 60 as his cadence but it is limiting.

 

[harryS]

What cadence do you need to go 18-20mph on these bikes?
There are e-bikes with full size wheels that will not reach 20mph if you restrict yourself to cadence 60.
I’m criticing the OP for wanting 60 as his cadence but it is limiting.

One time i fell 1/2 mile behind when a car in a car stopped to ask me a question about my 20" folding bike. I was pedalng like a circus clown to get to 20 mph (calculator says 75-80 cadence with 52/11 gearing) to catch up. The motor tops out at that speed too, so it was helping.

 

[michaelmac]

PaD I'm not really sure what cadence I normally peddle at. I just picked 60 because I googled normal pedal speed for a casual bike rider, it gave me the 60 RPM cadence. But, as HarryS said,,, to get above 11 or 12 miles an hour I feel like I'm pedaling way too fast ,,,, like a circus clown. Just trying to get comfortable with the new ride. Also, I'm changing from bicycle to a trike so everything feels different.
Thanks for all the replies,,, keep them coming

 

[Manu]

The machine weight?pounds,kilograms

 

[michaelmac]

The Terratrike site says 56 lbs (26 K) total weight .And ,if it matters I run around 225 pounds ( 102 K ,,,looks better in K's )
thanks for the replies ,,,keep them coming , I'm learn stuff ,,, like I'm only 16 stones ..... that sounds much better than pounds :^)
m