Pro Connect - Pedal Keeps falling off!

[timelordUK]

Hi.. i wonder if anyone can help.
I have had my Pro Connect for 18 months now and have ridden an excess of 2000 miles on it. Suddenly on Monday the kerbside pedal just fell off. The nut rolled off somewhere never to be found. I initially blamed myself for not checking the nuts recently. After a long walk home I bought a new set of nuts. PLaced them on and used a socket wrench to tighten nicely.
About half way to work today it came loose again..... I tightened then after a few miles it was loose again. Am i doing something wrong here?

I can't understand why this is suddenly happening.

regards

 

[Mussels]

The pedal is unlikely to fall off as it's a left hand thread and tightens itself in use, did the pedal and the crank arm fall off as one?

 

[timelordUK]

my mistake... yes it is indeed the whole crank that comes off with pedal still attached....

 

[Lloyd_50cycles]

Hi TimelordUK,


This sounds to me like the taper on the cranks has worn out. If you give me a call on 0844 800 5979 and give me your address I'll pop a complimentary pair in the post to you tomorrow.

Kind regards

Lloyd

 

[Barnowl]

Yes there's usually a large nut or bolt in each crank arm that holds it to the axle. This needs to be checked regularly and should be kept tight especially in cold weather. If a crank arm has come a bit loose, there's a good chance that it's been distorted. If so, you end up re-tightening the crank bolt often, with the crank still continuing to come loose. Which sounds like your problem .
It probably needs replacing. If you let it go, the axle may become misshapen and need to be replaced.

 

[timelordUK]

Got the replacement cranks from Lloyd at 50cycles - brilliant guys... so quick and helpful on the phone!! Certainly no complaints from them at all!!

However, replaced the left crank... can't get the right one off no matter how hard I try...

but the left one still keeps working loose, it feels funny to pedal as well, like it is not straight... is there a knack to getting the crank on correctly, or should it just slot into place....?

any advice gratefully received!!

 

[flecc]

It should just fit neatly onto the square taper. Have a look at the tapered flats on the spindle to ensure there's no ridging that's stops the crank tapers from fully seating, then make sure the crank is fully homed on the tapers and sitting straight before you tighten the nut.
.

 

[Lloyd_50cycles]

To remove the cranks you need a crank removal tool. It is a device that pulls the crank from the tapered axle, and can be found in all good bike shops. Make sure when fitting the cranks that they are done up tight, otherwise the same thing could happen! The recommended torque is 45Nw if you have a torque wrench, if not then in lamens terms that means "tighten them until your arms feel like they are going to fall off", or "very very tight". DO NOT use an air gun or similar, it will break the crank bolts.

It is also worth noting that the tapered axle must be clean and free from all dirt/grease/oil.

Any problems, please feel free to call either myself or Simon on 0844 800 5979.

Kind regards

Lloyd

 

[Mattyduk]

or a sonic screwdriver....

it's late and I'll get my coat....