ATU question GS1000?

[CockneyRick]

So when reassembling my ATU i had the body, 2x arms, 2x circlips & 2x O rings.

I don't recall the ATU having any but they're in the bag i had when i took it apart?

I have fitted one arm with the O ring underneath but it just don't look right? Or is it just me?

 

[CockneyRick]

Also the smaller arm by the spring in the diagram pic shows it fitting into a recess, mine doesn't have that. Is that normal too?

[Poldark]

That doesn't look right.  O-rings are normally used to seal fluids; nothing to seal there.  I looked at a spare one from my box of parts; no evidence of O-rings.  Is your "bag" a rebuild kit or just a bag holding the small bits from when it was disassembled?  If the latter, maybe the O-rings are for something else and they inadvertently ended up in the bag.  Try assembly without them, then test it.  Should have free, smooth motion, no binding.

[CockneyRick]

Yep, just a bag i plonked em in. Perhaps they were in the bag before & i didn't notice!

Has yours got the recess?

[Poldark]

Mine looks similar to the one in your first photo including the "ND" stamp; so it's Nippon Denso.  Within a particular year/model, ignition components were sometimes sourced from different suppliers.  They all worked the same, but looked slightly different.

[CockneyRick]

The first pic is an internet one, mine is the one with my fingers.

You can see the little round nodule on mine not locating into anything?

[Poldark]

Now that I look closer, you are missing a piece.  Pic with your hand: shiny cylindrical shape is a bearing surface. There is a piece that slides over it with the locator notches.  Closely compare your two photos.

[CockneyRick]

Yep knew they looked different. I'll have to hunt around & try find it. Cheers matey  

[Gixer1460]

The bit you seem to be missing with have a 'tag' on the outside - this is the bit that passes the ign. pick-up to trigger the spark. It moves / revolves via the little bump - as the arms move out against the spring through centrifugal force, they force the tag to advance its position in relation to static position. Its clunky and mechanical, but it works. See Picture - not GS1000 but similar 

[Poldark]

Or if an earlier model with points ignition, it will be an eccentric cam lobe instead of the tag.

[CockneyRick]

7 hours ago, Poldark said:

Or if an earlier model with points ignition, it will be an eccentric cam lobe instead of the tag.

I think this version may well be mine, i'll go in garage later & check the crank end to confirm  

[Poldark]

Crank end should be the same on both.  Years ago, I was in a bind when the electronic ignition module on my GS550/650 burned out.  I was far from home but able to get to a small motorcycle salvage.  Swapped out electronic for breaker point ignition.  At the time, I didn't know the difference in resistance ratings on the coils.  It ran great until the lower resistance coils burned up.  I should have taken the coils from the donor bike. I remember the donor bike being a cb550; Suzuki and H**da used a common supplier for ignition components.   Or maybe I was punished for installing parts from a H**da in my Suzuki?

[CockneyRick]

Got a Dyna S on it & remembered the cam does it, what a fookin dope! 

[Gixer1460]

I was going to add a picture with my others but realised it had a Dyna rotor on - LOL would have saved some head scratching!

[CockneyRick]

And the whole point of taking it apart was to file off the hooks on the arms, that apparently helps with starting & the dreaded "clang" kickback on the starter clutch!

[Gixer1460]

Never heard that one before? In the 'rest' position the ign. is most retarded so plug firing is close to TDC so kickback should be reduced. It's when the mechanism malfunctions and you try to start with the pick up advanced that causes the kickback ie. too much cylinder pressure to get over TDC.

[CockneyRick]

Read it in an article a while ago. Gotta give it a try as it really is very disconcerting when it happens.

If it don't work, then that's another "remedy" fail off the list!