GTS Valve Lash Adjustment
Overview
This article demonstrates the basic technique for valve lash adjustment on the GTS. The key to this operation is tilting the engine far enough upwards so that the valves are accessible from the seat opening, using a motorcycle jack to tilt and raise.
Procedure
The steps to drop the engine for the maximum amount to adjust the valves are:

1) Remove the seat, pet carrier, and fuel filler panel. Remove the nuts rubber boots, and washers from the top of the shocks.
2) Remove the transmission cover, you'll need access to the variator nut to rotate the piston to TDC (top dead center).
3) Remove the three screws that mount the air filter, no need to disconnect the intake hose, it just needs to swing out of the way of the left shock.
4) Remove the spark plug boot. Take the wire out of the clip at the front of the engine compartment to give a bit of added slack when removing the boot.
5) Unclasp the bundle of wires on the top of the water pump.
6) Remove the muffler.
7) Guide the throttle cable around the ECU.

I used the Sears Aluminium Jack (about $140 on sale). It has removable lift extenders, and I found if I used only the one in the rear, it helps balance the scooter on the jack. Using both, or none (keeping the 'platform' level) made the scooter unstable as the rear rail is just at the balance point, making the front wheel lift high off the ground:

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Lifted off the ground


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The jack rails wind up just behind the battery drain (at the front) and just picking up the end of metal frame just before the plastic trim pieces


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This bundle of wires on top of the water pump needs to be loosened from the clip


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I took this opportunity to install the brass Moto Amore GTS muffler bearing. That edge of that curved bracket would put a lot of strain on the pipe and mounting studs for the muffler if left in place


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I had to guide the throttle cable around the ECU. (pay no attention to the valve cover resting on top of the fuel injector)


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Using a mirror to align the 4V mark on the head


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Adjusting the intake valves


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Adjusting the exhaust valves


The trickiest part was lowering the jack with one hand while guiding the frame back onto the two shocks with the other hand. I needed three hands. I failed to take a photo, but the trick I used was to lower the frame just so the studs on top of the shocks were just below the frame. I capped the studs with two small deep well sockets (10mm and 11mm) through the holes in the frame. The sockets guided the top of the shocks through the holes in the frame as I lowered the jack. Original post contributed by MV user starreem.
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