I think it’s reasonable to say that Aprilia got it right when they chose Rotax and the rock-solid V990 motor for their range of bikes in the late 90’s. Bullet-proof doesn’t quite do it justice, especially in the de-tuned Caponord variant. But even this wonderful piece of Bavarian engineering has it’s weak points, and probably the one most obvious from a service-by-service aspect is that damn annoying magnetic plug in the crankcase.
Yes, little old AP0241782 can be easy to install, but a stress-breeding mega-monster when it comes to it’s removal. Stubborn is just too understated for how this little sucker can behave! Even with a brand new, high quality hex-key you feel the fear rise in your throat as you apply more and more torque – until finally with a loud ‘crack’ it gives way while your knuckles accelerate toward the floor at light speed. Or as has happened on the odd occasion, the head sheers off!
Over the years I’ve tried removing it with the engine hot, cold and in-between …. with prayer, witchcraft by a full moon and plain old cursing. In the end the best remedy I stumbled upon was a bag full of the little suckers donated by a friend. Spoiled as I was, I could afford to be decadent and change the plug for a new one every three services. By that time the fit between the screw and hex-key was getting a little stretched. But then one day, the bag ran dry …. oh my!
A little online digging threw up a bit more info regarding Aprilia numbers and options. It turns out that the magnetic plug AP0241782 has now been superseded by 2R000498 AND there is an optional washer offered if you want to use one. The 07-09 RSVR and 07-10 Tuono used the same plug AND also had the crush washer AP0250640 fitted. This washer is now sold listed as a usable option on all engines that use this plug. Does it make a difference? I’ve no idea as I’ve not tried one, but I guess it moves the mating surfaces from the taper to the screw head/crankcase and washer. In the end I went a different route used by many others over the years.
Following the recent footsteps of my old mate Beasthonda, I dipped into my pocket and purchased a KTM mag plug – 58030021100 for the princely sum of just under £9 compared with the Aprilia part retailing at £32. This saving alone is worth moving away from the Aprilia part! Now the eagle-eyed among you may have noted that the magnet on the KTM plug is longer than on the Aprilia one and be concerned that this could cause a possible oil restriction – fear not. The 10mm magnet (versus 8mm) fits into a cavern …… the space inside the crankcase behind the magnet goes back at least 50mm, so there’s tons of room around for oil to flow by. So, job done ….time to move on with the rest of the lockdown service.