I just bought a used 20 inch bmx type bike for my son, nice bike but both brake levers are super loose and have a lot of wiggle room and give to them. The front brake will function when squeezed, but since the lever wiggles so much it doesn't seem very safe. I don't have much experience with fixing bikes, just wondering if anyone knows a simple fix.
Thanks a lot!!
Did you already try to tighten the levers up with the correct size Allen wrench ? Also Post a picture.
Good maintenance to your Bike, can make it like the wheels are, true and smooth!
I have the same problem. My SD 7 (an upgrade) sheared the pin that anchors the pivot of the brake arm to the frame. So i couldn't just choose another of the 3 small holes in the frame boss. So i tried out a new Promax front V brake, a brand often seen on kids' BMX bikes. Screwing both arms in all the way, there is still too much play between the arm and pivot on each side, so that the return springs escape their housing. No adding of washers or using different length bolts worked, so i had to reinstall the stock pair that came with the bike.
It's hard to believe that Promaxes wouldn't be standardized like other brakes. Is that the problem, or am i missing some step?
No. Let me try this again: By lever i meant v-brake arm. One SD 7 arm won't spring back out, as the anchoring pin in the tension adjuster barrel (that pokes into one of 3 little holes on the fork boss) is sheared off. The SD assembly looks like one piece since i can't get it apart to switch out the pin. If i could it wd. be easy.
So i tried replacing both arms with Promax ones, and they don't fit. They would if the mounting rods coming out of the front fork (on which they pivot in an out) were shorter. The upshot is the arms wiggled and the return springs jumped out from their little restraint tabs, so i reinstalled the stock brakes i'd removed for the SD 7's.
Which prompts the following questions: What the frock is with Promax products, and is there any way to open an SD-7 barrel? Also, since you mention caliper brakes, i have a hole in the stem of my front fork which i thought was for a basket mounting or front fender (since the fork has v-brake bosses already). Are these holes generally for caliper brakes? If so, i'll check the rear fork for something similar and bung one in there...
BTW, when does one start a new thread versus continue the old one if the subj. is relevant? Thanks for your patience.
A new thread for your specific problem might attract more viewers, ie: New Brake Arms Don't Fit Old Studs, might garner more interest.
I have 2 sets of Promax V-brakes that interchange OK, but I didn't buy them, they came on used bikes.
That hole you are asking about is normally used for mudguards/fenders/reflectors/Fancy Lights.
Then maybe my Promaxes are the kiddies' version--they are thinner at the pivot in profile than Saccons or Avids. Following your idea, then, i installed locally available caliper brakes--successfully--after bending the brake pad grips to fit the rim. (the mounting hole is in a plate welded between the seat stays, so the brakes sit at an angle to the rim, not perpendicular). A local welder also contributed a backup plate with bolt hole to reinforce the above mentioned mounting plate. They work OK but are cheap and flexy, resembling your scan.
Let me share a trick just learned for keeping the cable sheath seated in the hand grip (caliper) or tensioning the cable spring (hub-mounted band brake). This takes up the cable slack so you can use both hands to tighten the cable at the brake itself. The otherwise useless Promax v-brake arm with cable grip screw (not the noodle arm) is screwed onto the cable, after pulling slack, and holds it there. After tightening the cable grip screw at the brake, unscrew the v-brake arm from the brake cable and throw it in the toolbox till next time.