Handy Randy!
By TMX Archives on 15th Sep 03
CHANGING TYRES can be an absolute bitch of a job if you don't know how to do it - make no bones about that. CHANGING TYRES can be an absolute bitch of a job if you don't know how to do it - make no bones about that. Okay, so your local dealer will probably do it for you for a few quid but sooner or later you're gonna need to do it yourself. And once you've got the hang of changing tyres it really is a piece of cake.To show us how to switch rubber with the greatest of ease I've recruited Randy Richardson. Randy's head honcho for the Michelin MX race tyre service that attends all the SXs and Nationals and looks after notables such as the factory Suzuki squad - although most of them had been busted up by the time I took these photos at the Millville round.His #1 priority at Millville was the #14 bike of Kevin Windham who's been doing a pretty good job of making the champ's championship campaign a little tougher than he had it last year when KW was taking a sabbatical. Well, the cookin' Cajun is back armed with a factory CRF450 and Michelin tyres and is doing a pretty good job.Firstly, you need to take care of the basics - starting with washing the wheel. I know this isn't always possible as you may be repairing a flat at the track but if you're at home you have no excuses. You need to make sure the wheel is clean otherwise it's twice as much work trying not to drop all kinds of crud inside the tyre.Now the wheel is nice and clean you need to get rid of the air - a valve remover is called for and a lot of factory mechanics have a valve cap with a remover built into it with a 8mm-thread bolt in to give leverage. Failing that, you can buy valve removers at petrol stations or any car spares shop. They're very cheap and you need one.Then slacken the rim lock (security bolt) nut to the end of its thread (leave it so the top of the threads are flush with the top of the nut) and remove the valve lock-nut from the valve stem.Now you need to break the bead. You're not actually breaking anything, just unseating the tyre from the rim. If the tyre has been on the wheel for a while it can be a bitch of a job (all the wheels Randy works on are for factory race teams so the longest one would have been sitting is a week which makes this part of the job easier for him - bloody lightweight!). To do this you need to support the wheel on the rim or spokes (an old rim off a car works well) leaving the tyre unsupported. Now stand on the tyre to unseat it - you can also use tyre levers to help although it's tough getting them into the gap between the tyre and the rim sometimes. Now turn the wheel over and repeat on the other side. Oh, and make sure you start work on the wheel side with the disc, not the sprocket (it hurts a lot less when the levers slip).Once you've unseated it, push the tyre into the rim and spray some WD40-type lube into the tyre to ease the process. Then take two tyre levers (you don't need massive truck levers, just sensible motorcycle levers - a company called Motion Pro do some good ones that you should be able to pick up at your local dealer) and with the rim lock at the furthest point away from you put a lever in the tyre on both sides of the rim lock and pull them towards you.Now take a third lever and, near one of the levers already in place, push it into the gap and flip towards you. Take the lever that's now redundant from the latest move and do the same again - soon you'll be able to take bigger bites out of the tyre and do this until it's all the way off on one side. Remove the tube by pulling the tyre away from the rim near the valve and pull the valve stem away from the rim. Easy!Now you need to remove the other side of the bead. Stand the wheel vertically and with the rim lock facing at three or nine o'clock, put a lever inside the tyre and over to the rim's outside edge. Then pull it over and with a soft hammer just knock the tyre around until it's off.You're now either going to replace the tyre or turn it to get a good edge back - if it's the latter then concentrate because there's nothing more annoying than putting the tyre back on the same way. Not that I've ever done that of course!Lube the inside edge of the tyre (the bead) with WD40 and, starting with the rim lock the furthest point away from you, push the tyre bead into the well on the rim (the lowest point where the head of the spokes are visible - well, under a rim tape anyway). With your hands push the bead onto the tyre as far as you can (some people can actually get this all the way on with their hands alone but not me or Randy) then lever the rest of the bead on.Now spin it over so you have the unseated side of the tyre facing you. Then take the tube, replace the valve and inflate it enough to get a roughly round shape and lay it on top of the wheel in the position you need it when it's inside the rim. Pull the inside of the exposed bead away from the tyre and place the valve stem into the valve hole in the rim. Once it's through the hole you need to thread the valve stem nut on, twisting it far enough down to give you room to get the airline connection on later.Next up place the tube inside the tyre by lifting the bead enough to stuff the tube inside, making sure it's not twisted or folded.Starting with the rim lock at the furthest point away from you, place the levers at seven and five o'clock (with the rim lock at 12) and flip the bead over, making sure you don't feel the tube under the tip of the lever or you'll puncture it. With your third lever start to take small bites around the bead, alternating sides so you finish at the rim lock. Go for four-inch bites at first, although you'll have to get progressively smaller as you near the end.Now for another tricky bit. To get the tyre around the rim lock you need to have a lever on both sides of the lock. With your third lever push the rim lock thread up to allow the bead to seat correctly. For this you may need another pair of hands at first - although as you get used to doing this you'll find eventually you can go solo.Now to inflate the tyre. You'll need to over-inflate to begin with to pop the bead out onto the rim but if you need to go over 40psi then there's a problem. If this happens simply remove the valve, break the bead, spray WD40 inside, replace the valve and blow it up again. It should pop out okay this time.Then simply tighten the rim lock down and set the pressure - usually between 12 and 15psi depending on the track surface. A higher pressure will help to prevent flats but will give worse traction...it's a compromise.There you go, all done - easy eh?Words by Doc Wobbly