Winfried

Hello

Overall, I'm happy with my new Giant Rapid2 Triple because it's light and responsive.

However, it's mega hard to start moving, to the point where I have to start on 50x14 (biggest chainring x third gear) and stand on the pedals. Even then, my knees don't seem to like this.

I was wondering what components are recommended to get a fast city bike that's easier to ride?

FWIW, here's the technical infos:
Thank you.

demoncyclist

stop starting in that big a gear if it is hard on your knees

bboy314

Sounds like you just need to use your lower gears. Maybe try riding in the middle chainring, and practice shifting down in the back before stopping, allowing you to start in an easy gear. This will be much easier on your knees.

Phil_gretz

Left index finger. Click twice approaching a stop...

Once you start out again and get "revved up", one click with the left thumb.

Repeat as necessary.

dabac

Well...
Personally, I wouldn't see much use of the 50 within city limits. 39-12 would be quite sufficient, giving me about 25 MPH/40KMH before spinning out. I really don't spend that much time above that speed. So stay off the big ring would be a starting point. Try to remember to downshift the rear too before stopping would be another.

If that isn't good enough, have the bike converted to an IGH. The Shimano Alfines are supposed to be quite nice. Then you can downshift while stationary.

ThermionicScott 

Are you one of those people who likes to keep their bike in top gear all the time? Now would be a good time to break that habit.

HillRider

Sounds like you need a lesson in gearing. If the bike is too hard to get rolling in that gear, use a lower one. A smaller chainring and/or a larger cog will make starting out a lot easier.

sreten

Hi,

You have all the parts you need for a very fast and
easy to ride bike, your just not using them properly.

Get your saddle the right height and learn to spin.
Always drop a gear or two coming to halt unless
its downhill or the wind is behind you.

Knee issues have nothing to with standing, they
are caused by too low saddles and too big gears.

rgds, sreten.

For the right height saddle you will always be standing
at a stop, except when next to a convenient kerb.

You've got gears, use them. The middle ring should
be your default in a city environment. Same on open
roads with the wind against you, the big ring default
for the wind behind you and any decent length downhill.
Fairly obvious when you will need the granny ring.

I've got a 52/42 and a 7s 14 to 28, and the idea of
setting off with 50 and 14 is utterly alien to me.
I've got into 52 and 14 going downhill at 30mph+.

FWIW I also always slow down, drop a gear or two, and
take it easy approaching major junctions / roundabouts.
Proceed through the hazard at a reasonable pace, but
you will be in a gear you can accelerate if you need to.

Same sort of thinking in the city, you should always
be running a gear you can accelerate in if you need to.

Homebrew01

Other than what everyone else has said, make sure your wheels spin smoothly. Lift them off the ground. Do they spin for a bit without rubbing brakes or frame ?
Then downshift ! I use a 50 x 14 after I am up to speed at about 20+ mph.
I start off in my 39 x 21 or so, then gradually shift up as I go faster, keeping my pedaling at about 90 rpm (count the number of times your right foot is at the bottom of the stroke )

sreten

Hi,

At 50+ 20mph+ is a fair lick for me and I can't do it with 52 x 14 on the flat.
I never use that gear on the flat, nevermind trying to start off in that gear.

52 x 14 is a downhill 25mph+ gear for me.

Youngsters who are faster than me should be pedaling at a higher cadence.
No doubt they can also push big gears a lot better than me, but apparently
your best cadence reduces slowly with age, so if you want to be fast, spin !

rgds, sreten.

caloso

I once did a Merckx style 10-mile TT on my FG with a 52x15 gearing (which is 3 gi. less than 50x14). That was plenty of gearing for the race, but riding through town to the start was hell. No wonder your knees hurt.

ThermionicScott 

About the same for me -- as fast as I go, I hardly spend much time in the 50/14 or 50/13 where my bike tops out. Now that I think about it, it's kind of discourteous to wobble around in one's 95" gear when the light turns green, while people behind them wait.

Winfried

Thanks for the infos. I'll try using the middle chainring instead and see how it goes.

I guess a 50 chainring is a bit big for riding in the city. What would you recommend for chainring + gears for a fast city bike with occasional hills?

Phil_gretz

From reading the information you've provided, your bike is fine for your purposes. Simply learn to use the gearing that comes on the bike. Stay in the middle ring while moving at your cruising speed. Shift to the small ring to start up again as you approach a red-light to stop.

It's unlikely that you need to change anything. If you have specific questions about how your bike works, or something that seems "not right", take the bike to a local shop for an inspection and tuning. Go over your questions with the technician there. He/she will help you.

kmv2

Learn to shift. Practice using the front, and avoid cross chaining.

https://www.youtube.com/watch?v=Q4x8Kq3o-mI

Winfried

I already downshift the back gears when coming to a red light, and upshift when riding away, but don't change the chainring because it takes a bit longer.

I'll experiment with the middle chainring and see how it goes.

Phil_gretz

As measured in hundreds of milliseconds?

rm -rf

Here's the speeds for your bike at the usual 80-100 rpm cadence range. Spinning higher cadences like this are way easier on your knees and your leg muscles.

From Mike Sherman's gear calculator

The 50 chainring is blue
The 39 chainring is black
The 30 chainring is red.


The middle 39 chainring is perfect for most riders on reasonably flat ground. You can efficiently ride anywhere from 11 mph to over 20 mph.

Drop to the 30 chainring before the road starts getting steeper.

The 50 chainring would be good on slight downhills (or if you are a strong rider that often pedals 18-20 mph or more)

cny-bikeman

It takes longer to shift but it's "mega hard to start moving" - do you see a bit of a contradiction here? If you take a second to shift and it saves you time and effort overall you are gaining, not losing.

rm -rf

Your triple bike is already just right. The middle chainring has a good mph range for many riders, and the 30 small chainring is great for hill climbing.


The alternative these days is a 12-32 cog set, and a 50-34 double chainring. That gets to similar low gears for steep hills, but the cogs tooth counts have bigger jumps between gears. With a triple, it's much easier to get that "just right" cadence.

cny-bikeman

Agreed - ride the middle most of the time, but avoid the 12 tooth cog in combo with it, due to higher chain angle and increase wear. Actually I'd say just forget the 12 tooth is there.

kmv2

Also don't shift under load, let off a touch as you shift. You should be thinking about it before you stop. Try it out and it becomes a habit. Better for your knees, and your drivetrain.

When cruising around, always try to keep cadence around 80-100rpm if possible.

Approaching a stop:
1. get rear cassette to a middle cog if needed
2. shift front to smaller/middle chainring (granny ring should only be for tough hills IMO)
3. shift rear cassette to large cog.

Taking off from a stop you're then in the best combo.

As you pick up speed,
1. shift towards middle rear.
2. shift to larger chainring.
3. shift towards smallest rear.

Shifting graphic:

Turtle Speed

Listen to the other advice you're getting in this thread - put that baby on the smallest front chainring when reaccelerating from a stop, and you'll go from zero to rolling with no effort at all!

Then shift up as you gain speed.

It works for cars, and it works great for bikes!

sreten

Hi,

Its simple - use the middle ring most of the time in a city. Use the big
ring on the open road and long downhills, use the granny ring for uphills.

Down shift a couple of gears as you stop for an easy start.

rgds, sreten.

Winfried

Thanks all for the advice. I'll get used to using the middle chainring instead.