Picked up a Diamondback Cobra 20" MTB for my 7-year-old son last weekend. Fits him well, but he can't downshift. It came with a SunRace grip shifter. I called the local bike shop and they recommended replacing it with a SRAM MRX Comp shifter. Brought it home, installed it, adjusted it....he still can't shift. Just doesn't have the grip strength required.

Is there an easier shifter to mate with a Shimano SIS 6-speed rear derailleur? I use SRAM thumb shifters on my bike, but I'm wondering if his little thumbs can reach the buttons, and strong enough to pop them down to the hardest gears?

Or should I just tell him to live in 3-gear until he develops some grip strength?

Dump the grip shifters entirely and go with trigger shifters like these Shimano Tourney version. I have used this style shifter in either 3 x 6 or 3 x 7 type for years. Cheap and effective.

Stupid for shop to switch you from one grip shifter to another.

https://www.amazon.com/Shimano-Tourn...er+3+x+6&psc=1

There was a posting I was trying to agree with when I noticed it was removed, probably because of word choice. Overall, though, I agree in a more PC way.

When a 7-year old has problems with a new bike most people wouldn't consider it related to his weakness. It's probably the fault of the store for failing to identify an issue (grip shifter strength) that happens regularly on kids bikes or the parent for failing to make certain the child could operate the bike before he left the store.

In my opinion, only weaklings blame their problems on 7-year olds.

BTW, I agree with wrk101. Go with trigger shifters like many 7-year olds use.

I replaced the Shimano Revoshift grip shifter on my daughter's Specialized Hotrock with an Altus trigger shfiter. She can work that well.

How do these work? Do you push the thumb shifter to downshift (up the cassette or freewheel) and then push the button for upshifts (down the cassette or freewheel)? I guess the button will do one cog at a time, but can you push the thumb shifter all the way from one end to the other at once, or does it ratchet, allowing just one or two cogs at a time?

thanks! What does the "3x6" mean? The rear derailleur has 6 speeds, but what is "3"?

can I buy just the right (rear) shifter, without the left (front) shifter?

hahaha, I'm just being a smart-a** on the Bike Forums; I didn't actually give my son a hard time about it in real life. I told him I would get this sorted out, which is why I'm here asking.

Which trigger shifter do you recommend? Do some of them fit small hands better than others?

The thumb button shifts down, ie go to a bigger cog.

The finger button shifts up, ie go to a smaller cog.

Usually the thumb button can downshift up to two gears in a full range of motion.

3x6 means 3 front gears (chainrings), 6 rear gears (cogs)

Yes you can.

Not to be pedantic, but this description applies to the right shifter (rear derailleur) only. For the front, the thumb shifts *up* (to a bigger chainring/higher gear), and the finger shifts to smaller chainrings/lower gears (*down*).
Steve

Maybe consider Di2 or other electronic shifting. It fits well with the video game generation.

Thanks -- you both answered my question (I may have asked it too vaguely). Yes, the thumb pulls cable and the finger button releases it one indexed click at a time.

And the front is friction only, so you slide it either direction. Personally, I much prefer friction front over indexed. Eliminates chain rub, allows small adjustments. And no, you have to buy the set.

+1 I would go with a trigger and 7 speed also for this.

My only comment is that a thumb shifter might be easier to operate. On the weakling side, I have a touch of arthritis in the left thumb. After riding a while I can't use my thumb with a trigger shifter, and not much better with a grip shifter. I installed an old Suntour thumb shifter for the left shifter, (you'll want Shimano
Tourney shifters), and I can literally grab it with the palm my hand to shift.

Something to think about.

John

If you actually cared about your child and were a decent parent, you would get him a bike equipped with Di2 electronic shifting.

sort of funny how this thread went from one extreme to the other. (A father harshly criticizing his son for not being able to shift even though he is just a little kid, when the emphasis should be encouragement for riding a bike....... To the othe end of the spectrum where there is a wacko statement that if you dont supply your kids with the latest electronic shifting that you dont care about them and are a bad parent)

the fricken internet, man. Palm in forehead

I built a bike for my wife which was eventually given to my mother. I put grip shifter on it. My wife found it hard to operate.

After reading this thread, i let my wife try my trigger shifter. To my surprise, she found it easy to shift. Those would go on the next bike i am going to build for her.

It was not supposed to be taken seriously.

Fricken humorless internet, man.

It's annoying but true - more expensive shifting really does have lesser effort. You can't get XTR shifters at six speed, though.

Gear shifting should be the least of your worries. Are his hands strong enough to use the brakes? In my bike store days, I occasionally refused to sell a bike when it was clear that the child was too small or too weak to ride the bike safely.

You need to lubricate the cables or adjust the "B" screw on your sarcasm detector. Or, better still, upgrade to a Di2 model!
Steve

+1000000

I put these on a mtb to replace grip shifters for my son when he was little. Made a world of difference!

If you want to take the kid on trails where they have to go any significant uphill.

I tell you what though, it's a very hard thing to get a kid to understand when (and even how) to shift, and to get them to use any gear but the hi/lo extremes.

Seriously, do you come in to threads JUST to disagree with people?

Obviously this guys 7 year old is smarter and a better bike rider than you were in your teens. Probably faster as well.

As for the OP:

I remember seeing special grip shifters designed for kids on a really nice kids bike once. I'll have to see if I can find them. (EDIT: After a quick google search, I've had no luck unfortunately... I should have taken a picture when I ran across them. Sorry)

I noticed they were REALLY easy to shift, more so than a typical grip shifter with new cables and housings. Then I looked and they were special grip shifters that were designed to be easy to shift.

I am fan of cheap friction thumb shifters and have often replaced bad twist grips with these at a bike charity I help with.

pretty easy to work, cheap, and durable (important on a kids bike)