GY6 project out of the house

Recent progress: EGR delete, exhaust header nuts came in and got installed, exhaust hangers secured with generic bolts from Hooten’s hardware.

Hardwired the SAE quick-connect for the Battery Tender Jr charger.  It’s a .75A charger that works well on the 7A scooter cell.  I use a bigger BT model on the larger equipment.

At this point it was time to start running the engine for more than second-long tests so I moved it outside.

I installed the new Gates PowerLink kevlar belt;  this requires removing the variator (forward pulley) which can be a biotch since it’s on tight (40 ft/lbs) and spins on the engine output shaft. There is a spanner tool to help hold the variator while you wrench on it but I’d been putting off buying it.  Finally did and it works pretty well.  The fingers were a little too thick and required grinding but after that all was well.

Got the CVT put back together.   Engine started fine but didn’t want to rev, seemed out of balance, and rear clutch engaged at low engine RPM. Wha-a-a-a-a-t?

I hadn’t taken the inner variator plate off (the one with the rollers and ramp) to see if any belt chunks had ended up in there. . I spun the variator around and looked in the holes; one of the rollers was stuck in a weird/outward position. I think this was pushing the belt outward as if the engine were revved, increasing the belt RPM and engaging the rear (centrifugal) clutch. Since only one was out this could also explain the increased vibration.

The variator rollers (OEM 18×14 13g each) had flattened considerably and were in need of replacement:
 photo 20160331_212855_zpsqbri3vzm.jpg

That’s how they wear so it wasn’t unexpected.  The dings on the side of the roller are not a function of normal wear.  One of them had shed some of the “shell” material;  I wonder if this caused the dings and/or the original belt failure.

I ordered a set of 18×14 13g sliders off eBay and some of those little v-shaped “variator slide” pieces that fit on the ramp to help it move in/out as the rollers push the ramp out. One was missing, or I dropped it, or it turned to dust with the belt.

Sliders replace rollers but they are polygonal and slide (surprise!) up the ramp rather than rolling.  They are generally a bit more expensive but 1) are said to wear better; and 2) widen the gear ratio a bit by moving both deeper (low gear) and shallower (high gear) in the variator pulley.  It’s not a huge difference but wear patterns on the variator walls are wider with sliders so the v-belt must be traveling a greater range.

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