Soak with penetrating oil, plusgas, WD-40 etc.

For tubing you could cut up an old knackerd bike frame or scaffold pole etc and use it as extra leverage over the spanner. A long pedal spanner to start with always helps, such as a park tool or cyclo product.

Don't forget that the left hand pedal is reverse thread! Both pedals tighten towards the front of the bike.

When re-installing, put a little bit of grease etc on the thread to make life easier when re-removing the pedals, dont do them up too tight, just nip them up  

--Last edited by Time Lord 1 on 2007-01-25 23:25:08 --

what size are grifter pedals , thread size

9/16

I have a few 15mm spanners that came from the boot sale.  I grind the side of them down.  So they fit between the pedal body and the crank arm.  Some bikes have plastic coated cranks and the pedal goes in the hole.  So theres not much spanner flat there.  Even thinner than a Cyclo spanner.  Also some pedal spindles have short spanner flats.  So a normal spanner disnae fit.
If the pedal is stuck.  And it has an adjustable bearing axle and a removable endcap.  You can pop the end cap off.  Then dismantle the pedal spindle.  Then I grip the pedal spindle in a vice, real tight.  No tighter than that.  Get a scaffold pole on the crank arm, if its a left arm.  Then really shove the pole.  It may be really stuck on though.  Remember use the correct direction.  If its a right side arm.  I cover the cog in a cloth.  Then grab it and try to move it.  
Those methods are not really for standard Raleigh pedals.  They are difficult to dismantle.  But there may be non standard parts on there.

a bit of heat also works wonders,but i mean a hot air gun ,not just a lighter,ive tried this methos several times after using oil and scaffold pole etc,few mins with the heat gun on the back side of the crank and around where the pedal actually goes into the crank,then a bit of wd40 sprayed on it ( the internal heat suck the oil into the crank) heat it again ,bit more oil ...and give the snanner a whack with a hammer and hey presto it should loosen,,,,just mind and let it all cool down before touching the crank