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Old 07-29-09, 11:28 AM   #1
DOS
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Kid not strong enough to turn grip shifter

My 9 yr old is not strong enough to turn the grip shifters on her new bike. I have played around with cable tension and housings to see if I could make it a bit easier -- some marginal improvement but not much. Is there anyway to adjust spring tension to make these things easier to shift?
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Old 07-29-09, 11:39 AM   #2
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No, but I've noticed that different models of (SRAM) gripshifters are easier or harder to turn. Is it the left (3 gear) or right (7 gear??) shifter or both? What model bike and/or shifter?
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Old 07-29-09, 11:45 AM   #3
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Its both shifters but more noticable with the front shifter. She can down shift (i.e. release cable tension) ok but up shifting is impossible for her. On the rear she can get it to turn in both directions, but again its easier when shifting from larger to smaller cog. The bike is this REI house brand with Shimano shifters http://www.rei.com/product/772040. Could be the answer is she needs to get stronger.
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Old 07-29-09, 12:44 PM   #4
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Fix would be silly, ie. replacing with trigger shifters. Unfortunately, she may just need the wrist upgrade However, as they say about kids, they tend to "get stronger and smarter each day, how about you?" I suspect this will not be a problem for very long.
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Old 07-29-09, 12:48 PM   #5
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Fix would be silly, ie. replacing with trigger shifters. Unfortunately, she may just need the wrist upgrade However, as they say about kids, they tend to "get stronger and smarter each day, how about you?" I suspect this will not be a problem for very long.
I did consider trigger shifters since they can be had fairly cheaply. But I think I would be trading in a need for stronger wrists for a need for longer fingers. Anyway, she seems content at the moment to spin around in the middle ring using only a couple of gears in the back.
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Old 07-29-09, 01:22 PM   #6
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My 9 yr old is not strong enough to turn the grip shifters on her new bike. I have played around with cable tension and housings to see if I could make it a bit easier -- some marginal improvement but not much. Is there anyway to adjust spring tension to make these things easier to shift?
Replacing the springs would depend how handy you are. Since the issue is going to larger cogs/rings, the springs in question are those on the derailer that she's fighting. Could be worth seeing if you can research derailers that have stronger/weaker springs, possibly? You might be able to replace the spring, but seems to me it would be a pain.

My thinking is to worry about the rear cluster and just leave the front in the middle for now, as you mentioned.
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Old 07-29-09, 01:56 PM   #7
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Is she trying to shift while stoped?
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Old 07-29-09, 03:14 PM   #8
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Old XTR rears had a spring tension adjustment. I always run mine on the stiffest setting, because the spring is what forces the upshift on the rear. It could be run softer, to allow easier shifting, with some degradation on the upshifts.

Way back when, there used to be a "worm" for lack of a better word, that applied tension to the cable at the derailleur. Haven't seen one in years, and I'm not sure how much help it would be anyways. It was just a rubber/latex tube that went around the cable and clamped in such a manner to apply a small amount of preload
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Old 07-29-09, 03:21 PM   #9
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How about lubing up the cable housing? I think replacing the springs in the derailleur would be really hard, and I doubt the shifter itself is causing any problems, but you could always check by disconnecting the cable from the derailleur and having her twist it about to see if it actually IS the shifter and not the derailleur...derailleur...
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Old 07-29-09, 03:25 PM   #10
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The middle front ring w/7 rear gears should be plenty for most conditions. You might try talking with REI's tech support/bike mechanics to see if they've run into this problem before.
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Old 07-29-09, 07:04 PM   #11
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She'll get stronger, in the meantime, she has a 1x9
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Old 07-29-09, 09:44 PM   #12
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Am I going to be first to say, "Tell her to HTFU!".

In all seriousness, even my wife's SRAM Attack shifters on her C'dale F700 can be a little hard for her to turn, so I think it is pretty normal. I've been thinking about switching hers to thumb shifters (probably in the off-season).
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Old 07-30-09, 05:18 AM   #13
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Is it possible to increase her leverage somehow? Attach a small lever that points AWAY from her that she can get a couple of fingers under and pull? Obviously safety is the most important, and you don't want any pointy things that can impale her if she drops the bike, but if you pointed it down and toward the front wheel?
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Old 07-30-09, 05:20 AM   #14
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if the bike is new, it may take time to break it in. have you tried lubing the derailer to see if that helps any? possibly lubing the lines also.
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Old 07-30-09, 07:07 AM   #15
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Update: Thanks for all the comments; the problem is definitely the shifter not derailleur springs (hard to shift even without cables attached). Flatmaster is correct that problem is part technique as my daughter does attempt at times to shift while standing still or moving slowly so it should lessen over time as she gets more skilled with the shifters. That said, the shifters are a bit stiff even for me. I found the following on MTBR.com:

If this works the same as the grip shifts I've torn apart, the detent spring is a flat spring bent into a curved U shape with a bump on one side. Your options are basically to pinch this U a little bit tighter with some pliers or to take a dremel sander to the notches on the shifter body so that the spring doesn't have to compress as far to get from one detent to the next.

So I tried the spring pinch solution on an old shifter I had lying around, and it worked like a charm. Once I pinched the u-shaped spring a bit and reassembled the shifter, it was noticably easier to shift. However, since I would have to completely remove my daughter's shifters from the bike, take em apart, then reassemble and put back on bike, seems it may not be worth the trouble since my daughter well get stronger and develop better technique over time so problem will solve itself. If there was an easier solution, I'd give it a shot but probably won't bother with above. That said, for parents who experience similar problem in the future, the solution is now posted.
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Old 07-30-09, 07:10 AM   #16
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I don't have much hand strength but I'm an adult and I have trouble using grip shifters on cheap juvenile bikes. The problem is as you have gathered the springs in the derailers that are too strong. Most of the responders here who are saying that she should harden up have NEVER used them themselves and they DO require more strength to use than the better units fitted to adult bikes. Seems stupid really. I've tried lubricating everything with mine but they are still heavy.

Keep an eye out for better derailers at a decent price on eBay is the best I can suggest.

EDIT: you responded first while I was posting. The twist grip shifters I had were OK when unattached to the derailer and in my case the derailer springs were just heavy, especially the front one. Its probably a bit of both. Thats cheap bikes for you.

Anthony

Last edited by AnthonyG; 07-30-09 at 07:14 AM.
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Old 07-30-09, 07:18 AM   #17
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I can't stand grip shift... you notice that SRAM has gone to trigger shift on all their good MTB stuff? Hmm...

FYI, I just bought a set of STX 7-speed shifters new with cables for ~$25. I got mine from Niagara cycle, but I think JensonUSA has the same deal. (I'm not happy with Niagara service).
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Old 07-30-09, 10:26 AM   #18
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well, not trying to hijack, but since the OP "solved" the problem and we're talking bout shifters, I have a question.

I bought a Giant Boulder which has the shimano "brifters" I think the term is (combo brake/shifters). I kinda hate them. I'd rather have one lever instead of 2 and I ALWAYS forget the 3 gear shifter is backwards from the 7 gear, so when Im goin uphill, I always shift up instead of down and loose all of my momentum.

Now I have a set of separate hand brakes and shifters ('99 era~ shimano thumb shifters) from my old bike I've been contemplating switching over. Could I swap w/o changing cables, etc? Or what type of shifters would you recomment on a 21spd mtn bike? Only thing I didnt like bout the thumb shifters is that if I'm not careful, they would rubbed on my hand and create a mild sore spot, unless I wore gloves, but dont always do.
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Old 07-30-09, 10:48 AM   #19
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Can you put on handle grips with larger outside diameters? Larger outside diameter grips would increase the moment arm enabling her to exert more torque on the shifter without an increase in arm or hand strength.
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Old 07-30-09, 12:42 PM   #20
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put some triflow in the crack of the barrell of the shifter and triflow the deraillure lines?
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Old 07-30-09, 03:30 PM   #21
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Can you put on handle grips with larger outside diameters? Larger outside diameter grips would increase the moment arm enabling her to exert more torque on the shifter without an increase in arm or hand strength.
Most kids hands are small. I think that by the time you made the moment arm long enough, they would have a hard time gripping the shifter. My kids can open a G2 bottle with some effort, but I know they would have a much tougher time with a jelly or even a peanut butter jar given equal required force.

It might help some, I just don't think it would make much difference.
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Old 05-24-14, 02:47 PM   #22
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The Solution!!!

Reviving an old thread here …


Recently bought Walmart bike for my 6 year old daughter:
http://www.walmart.ca/en/ip/20-rave-girls-bike/6000077806829

Actually a very decent bike for the $89 on sale! Raleigh, made in Canada, Real Shimano shifter, everything well adjusted, seems very solid (although heavy). I really wanted gears so she could climb hills, and maintain a fast pace when biking with me.

But like so many threads on the internet complain about on these cheap kids bikes with grip shift, at 6 years old she did not have the wrist strength to turn the shifter (especially down shifting to second or first). If she tried as hard as she could (with two hands and her whole body), she would destabilize the steering while riding so it came down to me doing it, or her stopping and twisting every time she needed to shift. Not a solution ... she also complained the skin on her palms became red and hurt when she did it herself.

No definite "quick fix" answer on the net, and since bike was new (and I could turn it just fine with a grown man’s strength) this was not a case of lubricate, change out kinked cables, or have warranty work done on the bike. And most bike shops just told me to “toss the Walmart bike, and get her a real bike because having their mechanic retrofit a good shift system would cost more than the bike is worth.”, and did not want to just sell me parts to experiment with.

Consensus seemed:
- Lubrication, new cables, twiddling and adjusting may help a wee bit - but not much.

- Just changing twist grip to a better one would not help, because problem is the tension in the derailleur.
- Trigger/rapid-fire shifts don’t exist for the 6-speed derailleurs on these cheap bikes.
- Trying to use a 7-speed trigger/rapid-fire would have the wrong spacing.

Finally one bike store guy looked in his catalogue and ordered a “Shimano SL-TZ20 SIS rear 6-spd thumb shifter” for (I kid you not) $5.00. He stated the thumb shift has much better “leverage” than a grip shift.

Took me 15 minutes to replace the grip shifter with this thumb shifter, and re-adjust the derailleur. Came with cable attached, and obvious enough how to swap them for the mechanically inclined. Also took the opportunity to change the handlebar grips at the same time since the original one next to the grip shifter is shorter, since the grip shifter itself comprises of half the grip.

PROBLEM SOLVED! 6 year old daughter can shift just fine now, while riding! She can climb hills, and maintain a decent pace with me. Best $5.00 I ever spent!!!

(Before) Too hard for a small girl to twist!





(After): No problem for a small girl:




Hope this helps somebody in the same predicament!!!

Last edited by steve_cay; 05-24-14 at 03:22 PM.
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Old 05-24-14, 02:51 PM   #23
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Yea grip the Thumb shifter like a faucet handle ,with the whole hand. seen it work with others

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Old 05-24-14, 02:59 PM   #24
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Yea grip the Thumb shifter like a faucet handle ,with the whole hand.
Nope, it has enough leverage for her to just use her thumb or fore-fingers. But yea, I guess a particularly weak child (or very stiff derailleur), could employe the faucet handle maneuver
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Old 05-24-14, 03:03 PM   #25
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this is sort of a a ' my kid's stronger than yours' sort of theme .
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