Bicycle Mechanics - Red Look Cleats

I'm having a real annoying problem with a new pair of shoes and cleats I bought recently and I was wondering if anybody can help me.

I am using a pair of shimano Rh-151 shoes with the Red Look cleats. The main problem is that after taking my foot out of the pedal a few times, the cleat shifts position quite dramatically on the sole of my shoe, which in turn makes it very hard to unclip my foot from the pedal.

I'm almost certain that the screws are as tight as they can possibly be, and I'm a bit worried of over tightening them and hence ruining the threads in the sole of the shoe. I have also adjusted the tension screw on the underside of the pedal, which makes it easier to unclip for a while, but eventually the cleat shifts position again. This is happening mainly on the left foot as this is the one I use as my standing foot.

I am at my wits end with this problem. One suggestion given to me was that perhaps the screws which attach the cleat to the shoe, may be just a tiny (1mm or so) bit long. I've already tried 2 different sets of cleats but to no avail.

Can anybody out there shed any light on this for me as I'm losing the will to cycle ! Any help will be greatly appreciated.

Thanks

Ian in Sydney.

Maybe you could loosen the tension on the pedal. If it's too tight, you might be needing excessive force to release your foot, which could be loosening the cleat.

Are you using the rectangular metal washers between the screws and the plastic cleat?

I had the same problem with Shimano shoes and Look cleats. I used a T-handle screwdriver to get the suffecent torque to keep the cleats in place. Consider the retention adjustment as well.

My Look cleats were shifting, so I added a lockwasher along with the rectangular washer, and that along with torquing the screw as much as I could seems to have helped.

Screws that are too long shouldn't matter; the nuts on most shoes are open-ended so a long screw would just stick up into the shoe.

You do not mention if the screws are still tight after the cleat shifts. If they are loosening up you might want to try a thread lock goo like Loc-Tight (sp?).

Another suggestion is to rough up the surfaces where the cleats contact the sole; they are both slick plastic and don't offer much friction. A dab of Goop (silicon-based adhesive) might be the finishing touch; it will keep things in place but will still allow you to remove the cleat when you want to.