WRENCH: 2016 Yamaha SMAX 155 Valve Adjustment (on the road!)

Neil is doing scooter maintenance in the woods again! Alan's 2016 Yamaha SMAX 155 has nearly 16K miles on the clock, and the valves have NEVER BEEN CHECKED! Neil just checked his SMAX before riding out for this meet, so he offered to help Alan with his scoot. Skip around with the chapter markers below.

Here are the fast facts for anyone doing the job:
- Yamaha specifies the check/adjust interval every 2000 miles! 😮
- Check and adjust valves while the engine is COLD!
- INTAKE: 0.003 - 0.005"
- EXHAUST: 0.009 - 0.010"
- Tappet adjuster screw: 3 mm square
- Tappet locknut: 8 mm
- Spark plug gap: 0.036 - 0.040"

2016 Yamaha SMAX 155 owner's manual PDF download (direct from Yamaha Motors):
https://library.ymcapps.net/library/om/contents/pdf/10/2SW-F8199-11_02.pdf

Time indexes:
0:00 Removing the variator filter and CVT drive cover bolts to access the crankshaft/variator nut
2:48 Removing the body center cover to access the valve cover
4:51 Removing the CVT cover and valve cover
6:54 Visually indexing the crankshaft and rocker arms to find TDC
8:14 Loosening the tappet locknuts with an 8mm wrench
9:44 Loosening the tappets with a 3mm wrench (these valves were WAY too tight)
11:33 Setting the proper valve lash using feeler gauges
13:08 The "tug test", resistance on the feeler gauge, should be able to remove and reinsert feeler
14:17 Tightening the locknuts and rechecking the valve lash
15:33 Adjustment complete, reinstalling valve cover and checking the spark plug gap
17:03 Reinstalling the CVT cover and filter
18:03 First startup still rough, weak battery? Subsequent restarts are better than before.
--
QM
quasimotard@gmail.com

#yamahasmax155 #scooterlife #motorcyclemaintenance
2016 Yamaha XC155G SMAX 155
motorcycle valve adjustment
motorcycle maintenance
scooter valve adjustment