Hills and Gears?

Question

I am still debating my bike purchase. I am not in good shape. I really like Giant Suede W. It is a 7 speed bike. The store could order in the 21 speed version. I don't like the colour of the 21 speed. I want to know if I can get by with 7. I asked a bit about this before but now have more information on the actual hills. The main ride with hills would be to and from work. It is 2 km of rise and fall. I figure the dips will at least let me get some speed for the hills. The biggest hill is 0.2 km long. The grade is about 6% with a high of about 10% near the top. Of course, going the other way, it will be mainly downhill. Do I really need 21 gears for this? Also, I understand the Suede W is made so that the low gear is more suitable for hills that you might expect for 7 gears. I am not exactly sure how this works. Maybe it has to do with the size?

Answer 1

the suede w 7 speed:
cassette Shimano 14-34T, crank Alloy 46T, 26 inch wheels.

you need what we call a "30 inch gear" to climb your hill when a beginner. you have a 35 inch. the rear cog is maxed out, you would have to change the front to about a 42 or 40 tooth.

(inch gear formula: front teeth/rear teeth times wheel diameter; FT/RTxWD=inch gear )

"Lower inch gears" climb hills better, "higher inch gears" make for faster top speed if you have the legs to push the pedals.

then your high gear would be about 78 inches, a bit slow for fast gear. If you change the rear cluster to a 12/34 you get a 91 inch gear. Even then your gear spacing would be rather wide as a 7 speed going from 30 inch to 90 inches. (chain has to be shortened, hope the derailleur still works- it should)

So ask the shop which would be cheaper, I suspect that the 21 speed would be cheaper.

If you don't like the colors, try the Raleigh Gruv, it is quite similar to the Giant suede with the feet forward design. ( I have a Raleigh Gruv 42 - front 11/32 rear 8 speed )

Answer 2

If the shop will let you, ask them to try out the 7 speed. Take it to the hill and try it. If you can get up over the hill, you're good. If you come to a screeching halt halfway up, you'll need the 21 speed.

I'd go with the 21 speed. A 6% grade with a 10% pitch is pretty steep. I ride an 18 speed to and from work, and there are some days I'm going up one of the hills in my easiest gear, just because I'm whipped from a long day and I just want to sit and roll easy up the hill. Also, the bike will be more versatile, should you really get into riding and want to go somewhere where there are longer or harder hills.

Answer 3

More speeds is better, not because of the number of gears, but the range of gears. Yes you can go up hills with the 7-speed gearing on the Suede, but it will be significantly easier with the 21-speed. The Giant Cypress DX might be a faster bike but just as comfortable than the Suede, but you don't get that sit on the saddle with feet on the ground feature of the Suede.

How does gearing work? Basically your shifter are moving the chain onto different cogs/chainrings. When the chain is on the smallest chainring in the front crank and on the largest cog in the rear, it is the easiest to pedal. When the chain is opposite combo....largest chainring in the front and the smallest cog in the rear, it is the tougest to pedal and the gear where you can generate the most speed. All the combinations inbetween offer a different balance of ease and power. You just sort of click through them to see what is comfortable on the particular terrain you encounter.

Answer 4

Personally, I think the 7 speed is enough, provided you have reasonably strong legs and aren't lugging a zillion pounds of gear.

I ride to work (29-32 km each way), with five long, steep climbs (2.8km at 9%, 3.2km at 7%, 1.4km at 12%, 4.6km at 10%, and 1.5km at 15%). And going home means I have to do the reverse of those climbs (they're all 'peak type' hills, so the back sides are approximately the same as the front).

My gearing started out at a 39F - 23R on 27 inch wheels (for 45 gear inches) on the two steepest hills. Now, a year later, I'm usually climbing them in 39F - 17R (62 gear inches). The lesser hills are usually 53F - 21R (68 gear inches).

At the beginning, you MAY have to get off and walk the last couple of meters to the top of the steepest hill. But if you persevere at it for a while, you'll find that you develop enough strength and overall cardiovascular condition to easily make the ride to work. And who knows? You might even start to ride longer distances, just for the fun of it!

Answer 5

21 gears sounds like a mountain bike. This amount of gears is essential if you are thinking of off road. For road work and only about 1.8 km, a standard road bike should be OK.

As for the hills, you might benefit from altering your set up a bit. Lower your handle bars, so that your weight if further forward, over the front wheel, perhaps buy cliped peddles, so that you can peddle in a push me pull you roatation, buy some bar end grips, again to help with posture.

However, for only a couple of km, you should be ok.

luck

Answer 6

Go with the 21 speed version. You said so yourself, that you are not in shape. You will need the range the 21 speed offers over the 7 speed.