Camshaft screw (XMAX)
K.I.S.S me: A screw too short can cause unhappiness (and a hole in the wallet).
Most Xmax riders have heard tales, a common problem with the top side of the engine. A short M6 cap screw that holds the camshaft retainer plate. Some unlucky riders have had this screw dislodged as early as 12000+kms on the odometer. The retainer plate also holds the rocker arm shafts in place.
When the screw comes loose, the rocker arm shafts can spin 360° hitting the decompression assembly located on the camshaft itself. When this happens, you will notice these symptoms, to name a few:
❌ Ticking noises (loose screw bouncing around)
❌ Bike being harder to start (damaged decomp assy)
❌ Engine stalling (screw gets stuck between timing chain and cylinder head)
Replacing the camshaft (because the decomp assy is not sold separately) will set you back at least $300. Not to mention metal shavings being thrown around the engine causing damage to other parts as well.
Solution: We offer replacing the screw with a longer part, torqued down to spec. The cylinder head has enough thread that allows for a longer screw to be used. This will cost you $100+ inclusive of labour and gaskets necessary as a preventive measure to a more hefty bill before other parts get damaged.
Also we recommend replacing this screw if you have not done so, during your nearest valve clearance. Just because it didn't happen doesn't mean it won't. Prevention is better than cure
In most cases, long screw good for holding things in place, short screw not so.
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Hakim has extensive experience in the auto repair industry, working in car and motorcycle workshops before opening up his very own, Bear's Garage. Contrary to his nickname, he's actually very friendly!