PAMCO Timing - Any ideas on this one?? Pete??

[pristic]

OK,

For those who dont recall - 1981 XS, all new wiring and PAMCO + e-advancer.
Had carb issues which I have solved by having them completely rebuilt.
The copper cup for the e-advancer spun a bit and threw my timing a little (still rideable but popping on decel and then started to 'pop and miss under load)

Got a new copper cap... pulled out the advance rod, put on the new cap (the way I was advised by PamcoPete) and even used locktight on the little pin to make sure it doesnt move again! All looks perfect, threw on the left side and tightened it up.

Now, bike wouldnt start, strange. Started messing with the timing and if I put it on FULL retard it starts but idles low, grumpy and pretty bad all around. Tried turning the plate to FULL advance, it starts, idles, revs (pops when you let throttle off) however when I try to ride it, it pops, and stutters under load (if I wind the throttle on slowly its not too bad, soon as I try to 'go' it pops, backfires, stutters, etc)

Ill hook up a timing light on Sat and try and check the timing but I find it strange that I cant get it started unless its fully retard or fully advance (or almost full)
Fuel, carbs, etc are all untouched and it did over 200kms on a run last week (before the copper cap got damaged)

My questions really are:
Timing.
1. When trying to set the timing I have the left piston at TDC then put the advance rod in and everything lines up. Is that right? Having said that, I dont see how with the pamco you can set it wrong, the pins simply line up and thats that, the copper cap doesnt allow me to put it on wrong... am I missing something here??
ie/ You cant 'adjust' the shaft, copper cap, and rotor with pamco, the only thing you can do is rotate the timing plate.

2. Advance rod assembly. I have done it as per Petes instructions (put on washer, then cap, then washer then washer then spring washer... and tighten it up... then put it in then put on the rotor side... when I tighten the rotor side up, I have absolutely NO freeplay in the rotor, cap, advance rod or anything... it turns nicely with the motor, but there is no play in/out or left/right... is there meant to be any at all? All seems good to me but just checking.

Cheers,
Peter

 

[TwoManyXS1Bs]

Hey, Pete, while you're waiting, have you seen this (second half):

http://www.xs650.com/forum/showthread.php?t=30186

 

[pamcopete]

Pristine,

The timing must be set with a timing light. You can set the plate to a preliminary position as shown and even check the timing as the engine is turning over before starting.

 

[pristic]

Hi Pete,

Thanks, ill do that, its just strange that in the SAME position as before (where it ran awesome) it wont run now.
Cam chain, etc all adjusted... timing is just out now.
I didnt realise how I could check timing before it turns over - can you elaborate? Or anyone?

Also, should there be any free play in the advance/timing shaft, etc - mine is all nice and tight, no free play.

Twomany - yep read that post earlier today and doesnt quite line up with what I am seeing.
Ill mess with it tonight again and see but its just really odd.

Think of it this way.
Pamco and e-advancer installed - running great. All good.
Take off the pamco and remove the shaft and copper cap, etc. DONT touch the timing plate (dont even unscrew it) then put it all back together and it wont run, and the timing is out.
Thats what I am confused about... I would have thought putting it all back in the exact position would mean timing is spot on again... since I cant screw up the copper cap rotation nor the rotor position... ?

Peter

 

[TwoManyXS1Bs]

Maybe you could visually compare the notch locations of the old and new copper cups.

The relevancy in that other post was pamco pete's mention of new aluminum cups.

Just a thought, I wonder if the spacing of the rotor to the hall-effect sensor affects timing...

 

[pristic]

Hey Twomany, thats what I am getting at, what other factors may change the timing...
I spoke to pete last week and he mentioned the ally caps... cant wait for that but now its installed 100% the way Pete said and cant move... so should no longer be an issue however cant time the damn thing. lol.

Unfortunately I cant compare the notches on the caps (emailed Pete about that yesterday actually) as the original one has been spun and the 'slot' is now about 6mm long as opposed to only a couple mm for the little pin.

When I get home today (children, wife and dog permitting) I will set it somewhere it will run and throw the timing light on it and see what it shows. I am also wondering how much change rotating the plate makes (ie/ if I rotate the plate 2deg vs 5deg vs 15deg...
I mean, how sensitive it is... thats more curiosity however does help. It may have needed only 1deg rotation and since I didnt use the light first time, I moved it around and then completely out.

Wanna know another STUPID moment?
If you look at a past thread, I said my little pin wouldnt fit into the camshaft hole (like the hole was too small/short... and I decided (since this time I had it all apart anyway) to use locktight - so I put the pin in, tapped it a tiny bit to hold it.... then used some large pliers to press it in... and BANG! the pin pushed THROUGH into the camshaft tube... I pushed it back up and its all good and locktight in there but OMG that spun me out.

Pete

 

[TwoManyXS1Bs]

Oh, yeah, that was probably a OMG! Moment.

You mentioned the deeper notch, wonder if it affected the rotor spacing.

Sensitive timing? Yeah, a 1° move of the timing plate produces 2° change at the crank.

Tell the dog this is important. He'll listen, they live for that...

 

[pristic]

Ah, yeah mate I thought it was tear down time! OMG bigtime...

No - regarding the notch I meant torn width wise not deeper.
This isnt mine, but its like this exactly... (stolen off google)

 

[TwoManyXS1Bs]

Oh my, that looks like a serious tear in what looks like a copper plumbing pipe cap. Yeah, a little wiggle there would translate to large timing changes. I understand from other posts that this is usually caused by improper assembly. Maybe your original timing was done on a slightly damaged cup, and after replacing the cup, the mechanism is now correct, but the timing is off...

 

[pristic]

Yes, thats true... could be that it was out slightly due to cup...
Thats the reason I cant compare cups though.

This one is assembled correctly. ok, time to time it ... grrr, was hoping when I went electronic ignition, etc I would have my timing all done and dusted forever

 

[pamcopete]

Pristic,

All in good time!

 

[pristic]

Thanks Pete

Ok fellas,

Just as an update, I got home WAY to late to start the bike (someone needs to invent mufflers that drop a bike to 20db or less just for 'night time testing purposes' ) haha

But I did open things up (pulled off all covers, etc to confirm a few things.
- The timing mark on the rotor is 100% dead on T line for TDC and the pin on the advance points directly at 12oclock. (or 6oclock depending on stroke, but anyway, its spot on... so the cam chain, etc (were all already adjusted) are all lined up fine and dandy. So simply must be simple timing that I need to set.

The second I can get to it to start it without waking up the whole street ill have the timing light on it immediately.

Does anyone have any tips for turning the pamco plate while engine is running? Seems like I have nothing to grab to turn it, my fingers dont fit (without the magnet thingo ripping them off actually) so while its running I guess I can only use a screwdriver to turn it while its running.
Am I a complete tool or is there some little trick

Cheers,
Peter

 

[gggGary]

I might suggest the Pete is saying time it while cranking it, doesn't have to be RUNNING.
IMHO Plugs out but on the caps and grounded will improve the accuracy of this "initial" timing.

 

[pristic]

ahhh gggGary, I see!!!... I was thinking some much deeper more meaningful thing he was referring to lol... was like "Oh you can time it without starting!"

I guess I could try, but she's kick only, no starter... which (I assume) makes it harder to do that. I need 3 arms and a spare kicking foot... THEN im sweet!

Ok, ill get cracking on it as soon as I can (leave for work too early, come home too late) I need one of those 'sea change' shows to come and take me and the family away and pay me TV royalties forever... THEN I will be all set!

 

[gggGary]

The wife or a 10 year old kid could do kicking duties with the plugs out.

 

[pristic]

Hah, dude thanks, I needed a laugh. My Mrs would break something even with plugs out, but the kid... hmmm, I will give that one a go.

Actually, the Mrs would be ok, just stirring. Took her up the street on it a few weeks back (yep solo seat but I put her on the tank/front of the seat 1/2 on my lap) and basically went 1st into 2nd up the road... the neighbours (about 4 different houses) came out because she was screaming SO much... ah, shes tops though.

Ill get her sorted on Saturday latest (if not sooner)

 

[XSLeo]

Ok, I was reading this thread, and in post #6 you said you pushed the pin in with pliers and it pushed it through the cam shaft tube.
There is supposed to be bushings inside the cam for the rod to ride in. On the advancer side the bushing holds the pin in place. If you can push the pin into the cam then you are missing the bushing.
With the E-advancer the rod won't spin in the bushings but the bushings center the rod in the cam.
When you install the cap on the rod and install the rod and rotor, when you tighten the nut on the rotor side this pulls the cap tightly against the pin and end of the cam.
This eliminates any free play end to end but with out the bushing the rod can be off center.
Being off center may effect the way the magnets in the rotor pass the Hall Effect
transistor. How much it effects things I can't say for sure.
This may be a part of why the cap was damaged.
Leo

 

[pristic]

Hey XSLeo,

Didn't really think about the bushes as f I recall I didn't need em or something. 1981 in Australia.
The advance rod goes in really snug and has absolutely no play at all.
First time I installed it and the copper cup did push the pin and held in place but the pin wasn't actually nicely fitted.
Like I mentioned it was like the hole was not drilled out enough from factory. I could never get it to stay nicely in place. NOW it ain't moving hahaha.

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[XSLeo]

If you can push the pin in so it comes out into the middle of the cam you are missing something.
On the points bikes, And I think Australia got points after 80 when the US got the TCI, It had a brass bushing and a labirynth seal on each end of the cam. The seal was a bushing that had grooves to hold grease.
On the advancer side the pin went in the hole and rested against the bushing. The bushing kept it from falling into the cam.
If what you have works, fine. If it gives you more issues you may need to check for having the right bushings in place.
Leo

 

[pristic]

Oh my god I almost took a sledgehammer to it. !!!
Timing spot on. Mark is on the T line on TDC.
Start her up and turn PAMCO till its in the correct range. All good.
Rev it and it advances to the proper point.
Now take for a ride and its fucked.
Noticed that WITH choke pulled its not a stutter etc. without it is spitting backfiring etc. BUT keeps idle fine and free revs fine.

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