One for the Techos

[Falcoholic]

Ok after all my spannering and gnashing of teeth etc i have stumbled on a wee problem.

Starter motor (mille) replaced, sprag and alternator investigated at the same time. The resistances of the alternator (stator) were outside the values specified in the manual of 0.2 - 0.5 ohm (mine read 0.8) so I am in the process of replacing it.

The arrow on the flywheel tells me that it should turn anticlockwise, however having pulled it off to inspect the sprag and replaced it all back again I was a bit confused about which direction the sprag should spin freely in and now I'm lost as to whether I've put it back on correctly. (yes yes I should have marked it i know)

The starter cog spins anticlockwise, the geared cog spins clockwise, the idler in turn spins anticlock which in turn spins the cog at the rear of the flywheel clockwise (against the arrow on the flywheel)

Questions:
Could i have replaced the starter motor with one that turns the opposite way(ie are all Aprilia starters the same) and in turn put the sprag on the wrong way round?
Should the flywheel always turn in the direction of the arrow even under starting conditions.?Or does it start by going backwards then spins forwards IYSWIM

The beast has not yet been out this year and I'm missing her desperately despite having a mates 07 plate Tuono to play on.

Cheers for any help.

Andy

[Chabby]

Dunno really - all the clockwise and anticlockwise has confused me. Which side of the bike are you looking from?

Have you looked at how to change your sprag on the AF1 site.
Its comprehensive with good photos so should help.

http://www.apriliaforum.com/forums/show ... eplacement

[Falcoholic]

Sorry,

Looking at it from the alternator/stator side. Or the near side, whichever you prefer.

yeah did all that but it's just the arrow on the flywheel that's confusing me. The starter motor turns anticlockwise and through the system of gears it turns the fly wheel clockwise but the arrow on the fly wheel turns counter clockwise.

[Chabby]

Its difficult to visualise without sitting looking at it but someone mentioned a bicycle freewheel in an earlier post and thats just another sprag.
So when the wheel is going forward, you can pedal backwards with no effect but it engages when you pedal forward.
The engines the same - if you imagine the starter motor as your legs on a bicycle providing the power to turn the engine over.
When the starters driving the engine,the sprags engaged, when the engine fires the starter disengages, ie the sprag freewheels - this is why on a pushbike you can stop pedalling when you go down a hill.
Imagine this while looking how the gears go together on your bike and it might help you get your head around it!

[joecrx]

i take it you replaced the starter motor as it was mot turning over, or was the sprag not engaging and or and starter just whiring around ,
but anyways i think the starters are all the same , so if you hear a whirring sound the sprag is on the wrong way if you have replaced it it might be round the wrong way ,
my bike has been laid up for a few months , i do start her up every few weeks or so till one day it did not start even with jump leads from the car , i was hearing a load click as it turned over , i thought i bent a valve, i know it wasint the solinoid as iv been down the rout before , it did misfire and i thought it was the sprag failing , turned out to be fuel or lack of it , filled her up and fired her up no problems .
i think the loud click was from the fuel injection system running dry , all is well now