I’ve gone through two seperate 20" in the last 18 months, both of
which ended up with exactly the same problem.
One of the cranks would keep coming loose, no matter how hard I or the
bikeshop dude fitted it on. Usually it comes loose within five minutes
of riding so I used to carry a crank remover around with me but ended
up getting rpetty annoyed with them.
I ended up using thread lock but the bike people say that on both of
them the axle and the crank have worn away.
I don’t know the brand and it’s not that easy to get uni’s here in NZ,
but they look like the same brand.
Has anyone else had any troubles like this?
PS I’ve had my 24" from Juggleart now for ages and had no problems at
all, very pleased with it.
are you saying the Locktite wore off, or the bits of the axle and cranks wore off? I had that problem as well. I fixed it using red locktite on both the axle and the 9/16 nut that screw on. It hasn’t budged.
One bike shop guy said that maybe the square hole in the crank arm may not be square anymore, and every pedal rotation was like a wrench undo-ing it more and more.
Luckily, in my situation, the permanent thread locker worked (permanent but removable, that is)
Wnat type of cranks are you using? how 'bout hub?
Re: 20 inch cranks always coming loose.
Just a couple days ago, on sunday, my screw came loose and I dropped my
crank, it had red loctite on it too, so I was kinda disapointed.
“Sofa” <Sofa.email@example.com> wrote in message
> are you saying the Locktite wore off, or the bits of the axle and cranks
> wore off? I had that problem as well. I fixed it using red locktite on
> both the axle and the 9/16 nut that screw on. It hasn’t budged.
> One bike shop guy said that maybe the square hole in the crank arm may
> not be square anymore, and every pedal rotation was like a wrench
> undo-ing it more and more.
> Luckily, in my situation, the permanent thread locker worked (permanent
> but removable, that is)
> Sofa’s Profile: http://www.unicyclist.com/profile/706
> View this thread: http://www.unicyclist.com/thread/17092
Can these Cranks be saved?
I had simmilar problems on my 24" united- although in my case, it was the result of abuse (it wasn’t made to do THAT).
A couple suggestions:
If you even susspect the crank is loose, STOP RIDING. There may be hope for a loose crank- but an anxel/crank set that has come loose and continues to be used will be rubbed round.
Press fit the cranks when you first get them- don’t use a mallet. Get a big C-clamp that will fit around the axel and cranks; tape large washers to the ends to form a receptical for the axel end in case the cranks are pressed on so far that the axel ends would contact the clamp. Do this without the nuts on the axel. Be judicious regarding how far you press the crank on.
As has been suggested, chemicaly lock the nut in place and/or use a split lock washer.
If your cranks/ axel are already damaged- THERE MAY BE HOPE. Try redressing the axel faces with a file untill they regain some integrity, and reface the crank socket; be carefull to remove as little material as absoluetly neccessary. Next press the cranks on, hard, so that the crank arm actualy streatches to conform to the axel. The axel ends will definately be poking out of the crank after this operation, so be sure to use the washers as a bridge to the clamp. If you have aluminium cranks handy, you might consider using them instead, as they will conform better to the axel (forget this idea if you have hard steal cranks- which It sounds like you do not).
This last bit is for the desperate, and if your cranks are bad enough, probably will not hold up to hopping and drops; but, hey- you weren’t taking drops on 'em, were ya?
Although I can’t personaly attest to it, some people have had success welding the cranks in place. Take percautions to protect the bearings- as they will be the last set on the wheel after this operation.
Considering your remote location:
a) order a bomb-proof uni
b) start a uni craze in Aukland so that a %of the gross national product is turned to uni production [by the way: America On Line just devalued itself more than the GDP of NewZealand]
c) employ a Master Mori Bonecarver to fabricate a new hub/crankset completely out of bits of shell and whale bone.