jimm7007

I am an old guy who bought a Schwinn Phantom Urban Cruiser to ride in my moderately hilly subdivision and in camp grounds.
Specs:
- 3 speed Shimano
- 27.5 x 2.5 tires
- 40 tooth front chain wheel (Chuan Wei, 5 bolt, BCD 110 mm)
- 23 tooth rear sprocket (converted from stock 20 tooth rear)
Peddling is easier with the 23 tooth rear (about a 15% lowering), but I still find the third gear much too high to use and want to go to final gear ratio which results in third gear being about same as stock second gear. I believe Shimano has about a 36% spread between gears. A local bike shop has advised that the 23 tooth rear now installed is max teeth available. Would appreciate advice regarding number of teeth/availability/source of increase tooth rear or decreased tooth chain wheel.

Oneder

Hi there. I would upgrade to 7 speed maxrange shimano cassette. Its range is 11-34. You will need new rear deraillieur, new shifter, new casette. The parts will cost about 60 bucks. I am not sure if you need a new rear tire but you can get a used one easily. Either that or you could get a new chainwheel up front that is 28 or 32. 40 is actually pretty big.

jimm7007

Thanks. Do you have any source for the 32 chainwheel?

Oneder

modernbike.com is a good site, I have been happy with all my purchases.

jimm7007

Thanks.

GamblerGORD53

Psssst....He is talking about an IGH. I think OP needs to ride more and get in shape.
With 40/ 23T the GIs are already plenty low. 35.9/ 49 / 66.8. Just perfect IMO.
I am 66. My 3 speed SA has 47.2/ 62.9/ 83.9. Lately I have been doing more short hills with the middle gear.

Oneder

He did say he is older, and he may have hills. Personally I don't like a 40t that is a bit much because I go mainly uphill, I keep it on a 32t most of the time.

GamblerGORD53

OP ..... Do NOT get a 32T. FAR too low and it's beyond the limits for that hub.
A 38T/ 23 is as small as possible really. Your bike is supposed to be a cruiser, not a mountain bike. That IGH hub is very easy to push actually.
My tour bike goes at 78 lbs all the time, it has 14 speeds.

Gresp15C

Some of the IGH's have a minimum ratio between chainring and cog, roughly 2:1 as I recall. But I wonder if that's really going to be a problem for the OP. That limit has to be based on the anticipated weight and strength of the rider.

Reading between the lines, if the OP is struggling with moderate hills in a residential neighborhood, then they are probably not a candidate for pushing the hub beyond its mechanical limits. In this case, I'd tell them: Go ahead and try a smaller ring in front, know that there's a limit for good engineering reasons, don't overdo it.

I've never heard of anybody breaking an IGH due to too much torque. If they're that strong, they've probably already moved to derailleur gearing for other reasons. I'm certainly not that strong.

jimm7007

Thanks for all the advice, gentlemen. This old 82 year old is considering your thoughts and please bear in mind that I (obviously) know nothing about bikes or gearing of same.
One of the reasons I broached going to gearing to achieve a new third gear of about same ratio as old second gear was the recommendations made by Sheldon Brown: "Bicycle manufacturers often assume that the middle gear of a 3-speed hub is the "normal" gear. They fudge a bit, lowering the gears in order to keep the top gear from being completely useless, but then the middle gear is too low for level-ground riding. A 3-speed hub will work better for you if you change the sprocket or chainwheel to lower all the gears, so you use the top gear on level terrain."

Oneder

You may need to look at your crankset and see if it can be modified, if you post what it is someone here can probably tell you. Otherwise you may need a new crankset to get 32 teeth chainring.

GamblerGORD53

40T/ 23 is in fact already at the point where 3rd is a flat gear. But everybody has different body abilities of course.
32/ 23 will wizzout at 15 mph.
My dad rode a too big single speed until he was 90, all flat the last decade likely. This bike was antique when we got it used in 1967 from his uncle. It's gear was the same as your 3rd. I never asked him what hills he ever did with it. I rode it in high school 3,800 miles. My uncle in Calgary was still downhill skiing at 82. I gave that up in 1980. LOL

Maelochs

Get a smaller chain ring. What other did, can do, want to do .... none of it matters. Pro riders can do things I couldn't , even when I was young and in shape. Why should I try to emulate them?

Set up your bike to work for you. Get a smaller chain ring and enjoy the ride.

jimm7007

I tried to post photos here. I am not allowed to do so till 10 entries. I sent photos of what I have to Wolf. They advised that the smallest chain ring that will fit on my bike is 34 tooth and that I would have to put in new real bolts to retain since what appears to be be allen head screws on mine are really rivets. My calculations, based upon input by noglider on 7/30/17 and 11/18/19 (not sure from whom for latter date) in this Forum, show that the 20 to 23 cog rear change amounts to about 15% lower. Additionally, going to a 34 tooth chain ring adds another 14.8% reduction for a total of 27.8% reduction.Not quite up to the 36% gear spread on the Shimano but sure better than where I am now. The Wolf stuff certainly appears top notch but pricey for putzing around my subdivision so if anyone has any thoughts on what would be best/cheaper for reducing the cogs on the existing 5 bolt, 110 mm, 40 cog ring, please share.
I am also checking with Modern Bike to see what they have.

rollagain

Is this the bike?

https://www.amazon.com/dp/B06XXJKPHF...osi&th=1&psc=1

A big problem I see with it is no front brake--for going down those hills again--and no way to even put one on without changing out that front wheel for one that will work with a caliper brake.

jimm7007

Yes, that is the bike. I have installed a front brake on it with standard wheel and, though not great, it does assist. I do not normally use it when in motion...just rear coaster. In fact, the best use is to hold the bike in one place when I get on/off. Ha. Recall I am 82. .Our subdivision hills are never over about 25 yards long so the coaster works fine and I have seen no fading issues, probably because I am going SLOW all the time.
Sheldon Brown recommended gearing to achieve a new third gear that duplicates the stock second gear. As noted before, the stock front was 40 teeth and the rear 20 with 27.5 tires. I think that results in 41/55/73. I have installed a 23 tooth rear and believe that results in 36/48/64. In order to arrive at what Mr. Brown recommends, I believe I need to go to a 34 tooth chain ring with the current 23 rear cog. If my long unused math is correct, I think that results in 31/41/55 and thus achieves what Mr. Brown recommends for the 3 speed Shimano on the bike when compared to figures of the stock bike..

However, I would certainly appreciate any of you folks comments on the logic in going to the 34 chain ring and source(s) for same.

Thanks.

jimm7007

I have received advice from Wolf that the 34 tooth chain ring is the smallest size made. Additionally, they advised that anything with less chain ring teeth would interfere with the bolt holes for the ring.
I guess that zeroes in on a 34 or greater number of chain ring teeth. Do any of you folks have one laying around in your used parts bin?
:-)

jimm7007

I have changed from 40 to 34 tooth chain ring. Works great for an 82 year old.