- Tue Dec 04, 2018 1:04 pm
#80486
A really healthy battery (can be AGM as well as lithium ion) will make a big difference to the reliability of electric starting, as will a properly set-up carb with no air-leaks.
The other aid to the sprag's longevity is to use the valve lifter when starting and stopping the engine. Getting the engine spinning fast enough before releasing the valve lifter means the sparks will be coming at the right time (the temporary voltage drop caused by the starter motor kicking in will have passed, though the later green TCI box is supposed to fix this: fit one if yours doesn't already have it. Also stopping the engine with the valve lifter reduces the tendency of the engine to bounce back on compression and briefly drive the sprag clutch in the wrong direction.
This is all well and good, trouble is the valve lifter is rubbish! Or at least the silly little plastic lever in the left-hand switch cluster is. I gave up on mine altogether when the AVL tappet cover cracked and leaked oil badly, and still got another 13,000 miles before my sprag went bang... Some owners have managed to get the thing working well enough by using an old-style decompressor/valve lifter handlebar lever. The other option is to modify the cylinder head to take the classic Bullet decompressor valve. This is what I did for my AVL hybrid and it works well.
A.