My Kid can not squeeze the brakes hard enough to stop
12-23-08, 05:10 PM
#51
free mallocs
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That's funny, I seem to remember coaster brakes being great for 20' skids, but not so hot if you actually needed to stop quickly
12-23-08, 09:41 PM
#52
Yeah. I Race.
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Coaster brakes are fun to make into freecoasters.
12-29-08, 09:53 AM
#53
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glad to hear you sorted that out.
other tips for maintaining brakes:
1. keep the rim and pads clean. occasionally clean the rim with glass cleaner or Simple Green. tkae the brake pads off and look for a "glaze." if they are glazed, sand the glaze off with a file so there is soft rubber instead.
2. lubricate the cables. use a teflon-based lubricant like Tri-Flow or Pedros. DO NOT use WD-40 in your cables!!!
3. set the lever at whatever angle is most natural for the rider. if he stands up most of the time, it may be better to have the lever angled down, not straight out.
4. spring tension: i am pretty sure that bike has a u-brake aka 990 (the "Diacompe 990" was the original u-brake for bmx bikes). there is a spring in each arm. these springs serve to make the pad pop away from the rim but also keep the brake centered. you only need minimal tension in each spring. any additional tension just makes the brake harder to pull.
that raises another point- that "brake equalizer" you are using is superfluous if you set the brakes up correctly. if one pad is touching and not the other, either your wheel is off-center or the springs are not tensioned correctly. if the left pad hits the rim first, that means that there is not enough tension in the right spring, because the right spring controls the left pad. you need to take a little pressure off of the right spring, or add tension to the left. this video should explain that part:
https://www.youtube.com/watch?v=waX3p7oFTmM
other tips for maintaining brakes:
1. keep the rim and pads clean. occasionally clean the rim with glass cleaner or Simple Green. tkae the brake pads off and look for a "glaze." if they are glazed, sand the glaze off with a file so there is soft rubber instead.
2. lubricate the cables. use a teflon-based lubricant like Tri-Flow or Pedros. DO NOT use WD-40 in your cables!!!
3. set the lever at whatever angle is most natural for the rider. if he stands up most of the time, it may be better to have the lever angled down, not straight out.
4. spring tension: i am pretty sure that bike has a u-brake aka 990 (the "Diacompe 990" was the original u-brake for bmx bikes). there is a spring in each arm. these springs serve to make the pad pop away from the rim but also keep the brake centered. you only need minimal tension in each spring. any additional tension just makes the brake harder to pull.
that raises another point- that "brake equalizer" you are using is superfluous if you set the brakes up correctly. if one pad is touching and not the other, either your wheel is off-center or the springs are not tensioned correctly. if the left pad hits the rim first, that means that there is not enough tension in the right spring, because the right spring controls the left pad. you need to take a little pressure off of the right spring, or add tension to the left. this video should explain that part:
https://www.youtube.com/watch?v=waX3p7oFTmM
Thanks for the help, 2 points to make.
1. The 2008 bike edition, there is a equalizer. So the engineers at GT thought the same as me. But I had to spend months to fix it.
2. Looking atthe video, the brake did not have a gyro, while my kids does. As you said, if all is perfect, brake calibration should fix the issue. Somewhere on my kids bike there was more play on one side than the other.
12-29-08, 10:13 AM
#54
Bicycle Repair Man !!!
marc... how old is the little one?
My 8 year old daughter is a wee little thing with very small hands but likes to ride very hard and aggressively... on her first bike I swapped out the stock levers for a long adjustable levers so she could get better leverage and on her new mtb I swapped out the stock brakes for Avids and made adjustments to the lever for reach. She can stop on a dime and only needs two fingers on the levers.
This first bike has been passed down to my 5 year old niece and she has no trouble using these brakes either as the action is really light.
I often find that on kid's bikes the levers are not optimal for smaller / weaker hands and changing this really makes a difference.
My 8 year old daughter is a wee little thing with very small hands but likes to ride very hard and aggressively... on her first bike I swapped out the stock levers for a long adjustable levers so she could get better leverage and on her new mtb I swapped out the stock brakes for Avids and made adjustments to the lever for reach. She can stop on a dime and only needs two fingers on the levers.
This first bike has been passed down to my 5 year old niece and she has no trouble using these brakes either as the action is really light.
I often find that on kid's bikes the levers are not optimal for smaller / weaker hands and changing this really makes a difference.
01-05-09, 07:42 PM
#57
Bicycle Repair Man !!!
My 8 year old on her new mtb (last summer)... she had no trouble using the conventional v brake levers after they were dialled in and after I replaced the stock brakes with Avids and Kool Stop pads and replaced and lubed all the housing and cable.
Note the two finger grip and the fact she is a wee little thing... she will be 9 at the end of this month and is often mistaken for a 6-7 year old.
The stock brakes were crap... they might have been okay for someone who does not ride as hard and aggressively as my daughter but she destroyed them in short order.
She can do full on stops and will often brake hard enough to lock the front wheel as well as the back without losing it...
On her old bike and on my oldest daughter's bike I used old Shimano canti levers which are long and straight and with the reach adjusted and levers moved inboard they offered some great leverage and stopping power.
I feel that kid's bikes should be equipped with far better brakes than they do as smaller hands have less power and an inferior braking system just makes it harder for them to stop well.
Note the two finger grip and the fact she is a wee little thing... she will be 9 at the end of this month and is often mistaken for a 6-7 year old.
The stock brakes were crap... they might have been okay for someone who does not ride as hard and aggressively as my daughter but she destroyed them in short order.
She can do full on stops and will often brake hard enough to lock the front wheel as well as the back without losing it...
On her old bike and on my oldest daughter's bike I used old Shimano canti levers which are long and straight and with the reach adjusted and levers moved inboard they offered some great leverage and stopping power.
I feel that kid's bikes should be equipped with far better brakes than they do as smaller hands have less power and an inferior braking system just makes it harder for them to stop well.
