spluttering tenere

[fward]

have another problem to share!
when i try to start the bike up in the morning or if the bike is left sitting for more than half an hour it splutters and misses like crazy for nearly exactly 20 minutes every time and then suddenly it behaves again and its ridable. When trying to ride it in this state you have to constantly clutch and rev it to make it go and keep it alive ....rides like a total pig - carb thoroughly cleaned today ... still persists .

Could this be the pulser that I just had rewired :confused1: ... please tell me no ...

please ..

[aukeboss]

Seems to be engine-temperature related. Tehn again you get back at either fuel or ignition systems.

1. To check ignition system, best to A) make sure all connectors etc are tight and clean and B) exchange with parts from known good bike to identify the culprit. Mind you, also the coil heats up so this could also be the problem.

2. Fuel system: could also be that your carb is somehow set extremely lean in the midrange. I conclude that, because you do manage to start it and to have it tickover, then when you open the throttle and load the engine it starts misbehaving. Checks: float level, fuel floa to the float bowl ok, setting of the needle in the primary carb: are all washers present and in the correct location?

Alternatively, if the only thing you changed between before problem - now is the rewound pulser (I'm sure you mean the coils in the stator that feed the ignition and not the two pickups btw) than this is a very strong indication that the problem has something to do with that. Measured the resistances of everything?

Auke

[*Touring Ted*]

I dont think this is related to electrics as the bike runs fine when warm ????

Sounds almost certainly to be bad fueling or carburation..

The carb is clean but is it tuned ?? Are you carb rubbers in good order ? No leaking from the plastic parts ?

The bike only seems to calm down when nice and hot.


Tell me.. how does it idle when cold and when hot ??

[Sly-Fox]

I had a similar problem with my XT, as Ted mentioned it turned out to be damaged rubbers on the carburettor intake manifolds; leading to too much air getting into the mix, which resulted in symptoms you describe.

Try this: Get a plant mist spray bottle thing full of water, start the engine and keep it running. Spray all around one side of the carburettor, then the other. If you've got a leak you'll find it easily by listening to the engine as you spray the water. My leak was so bad that a fine mist of water, sucked through the cracks caused the engine to stall.

It'd be a good way to eliminate it as a problem if nothing else.

[fward]

thanks guys
when I inspected the cables to the pickups I saw one wire slightly exposed and earthing off the case. Re insulated it and bingo - bike starts and from cold works fine across the entire rev range. Strange why before, after 20 minutes it ceased earthing off the case ??? - maybe oil circulating was getting between the exposed wire and the case. Happy! So all that was left to do was pick up the new battery I left charging overnight in a shop and then I could hit Colombia!
I have jumpstarted this bike off other batteries ( I have two batteries!) a million times but for some reason unknown to me yesterday morning I touched the positive off the negative and bang big spark. It took a small piece off the donor battery positive terminal
Got new battery, tried tow start ... couldnt get bike to start. Eventually it did after much rewiring and reinsulating but rougher than before. Now it wont start at all. Am extremely worried i might have damaged the CDI with the power surge ... is this possible?

Auke - yes it was actually the two pick ups I had rewound - dont ask! Some useless electrician in Peru was convinced the pickups were a previous problem and proceeded to hack away the sealed casing with a nail and a stone on the pavement ( I kid you not .. I was that desperate) until he could remove the old coils and rewind anew! Of course it wasnt the problem but since then Ive been travelling with a very dodgy pickup.

I also discovered today that my stator and pickups havent been getting much oil for months. I cleaned the two oil entry points in the crankcase and found the bottem one was blocked solid with silicone. The difference now after I turn over the bike and remove the crankcase cover is startling .. oil everywhere now.

[aukeboss]

Although the stator and the other stuff in there are suposed to be covered in oil, it does not hurt them when they are not. No worries there. However, if there is so much sh*t residing inside your engine I'd clean that out to avoid any gunk blocking a critical oil channel.
As for power surges and CDI's, no problem: the starter circuit is separate from the ignition so damage highly unlikely, further, you got it running again.
So, it's something else again.

Auke

[fward]

cheers Auke - thats good to know, i am about to go at the wiring again now.
Could you help me on this one please .... I measured the resistance of the pickup coils. Instead of 3 wires from the pickup I have 4 now! The guy who rebuilt the pickup last ran a 4th wire (earth?) from one of the pickups.

So I now have
the white/green and green coming from one pickup
white/red and black (the new wire) from the other pickup.

when I measure the resistance between the first combination (w/g and g)
I get 110ohms

when I measure the resistance between the second combination (w/r and Bl)
I get 105ohms

Is this the correct way to measure? The clymer manual I have says to measure the resistance between the w/r and w/g only but I cant get a reading this way?? (Clymer says 90 - 129 ohms is the range)

on the source coil Red to brown I am getting 350 ohms (at RX100 too).

The Clymer says 160 - 240 ohms is the range - so does my source coil have too much resistance? and which is slightly better - too much or too little resistance?

Finally the two earth? wires from my pickup ( green and black) are going straight from the stator harness into earth at the battery - not to the cdi. The green wire from the cdi that I presume is where they should go is just hanging open. What do you think of this? Bike was running ok before with this set up but how good bad is it?

Is that green to the cdi an earth for the pickup and if so should I wire the two pickup earths directly too it?

Appreciate the help if you or anyone else can do so ... I know its not the funnest thing to be doing on a sunday ... contemplating my electrical nightmare ...

thanks all

[aukeboss]

That's what I can make of the colour coding at least?

Originally Posted by fward

cheers Auke - thats good to know, i am about to go at the wiring again now.
Could you help me on this one please .... I measured the resistance of the pickup coils. Instead of 3 wires from the pickup I have 4 now! The guy who rebuilt the pickup last ran a 4th wire (earth?) from one of the pickups.

So I now have
the white/green and green coming from one pickup
white/red and black (the new wire) from the other pickup.

when I measure the resistance between the first combination (w/g and g)
I get 110ohms
** Should be 90 - 130 Ohm, so OK

when I measure the resistance between the second combination (w/r and Bl)
I get 105ohms
** OK

Is this the correct way to measure? The clymer manual I have says to measure the resistance between the w/r and w/g only but I cant get a reading this way?? (Clymer says 90 - 129 ohms is the range)
** It's not, if you measure like that you should get 180 - 258 Ohm. Mr. Clymer is wrong then.
So, measure w/g - g and w/r - g (black in your case)
Can't get a reading? But green and black are connected through earth? Check connections ...

on the source coil Red to brown I am getting 350 ohms (at RX100 too).
* Should be, indeed 160 - 240 Ohm

The Clymer says 160 - 240 ohms is the range - so does my source coil have too much resistance? and which is slightly better - too much or too little resistance?
** Normally theze coils fail thorugh internal 'short circuit'. Increased resistance points not to that, so if the bike runs with it, OK. However, maybe there is somewhere a bad connection causing this. Try to find it, will increase the energy available for the spark.

Finally the two earth? wires from my pickup ( green and black) are going straight from the stator harness into earth at the battery - not to the cdi. The green wire from the cdi that I presume is where they should go is just hanging open. What do you think of this? Bike was running ok before with this set up but how good bad is it?
** Not as Mr. Yam has designed it. The green and the black should go together to the green wire on the CDI. Trying seems to me without danger of frying something.

Is that green to the cdi an earth for the pickup and if so should I wire the two pickup earths directly too it? According the scheme it should not be earthed, it's just a common connection for the two pickup.

Appreciate the help if you or anyone else can do so ... I know its not the funnest thing to be doing on a sunday ... contemplating my electrical nightmare ...

thanks all

Suggest, with the scheme, to bring the entire system back in the state it should be in. Then start from there ....

Auke

[fward]

cheers Auke
have just dropped the stator assembly off at an electrician to rewire the ignition coils ( for the 100th time on this trip! ) to bring them back down to the 160 - 240 ohm range from the 370 ohm range I am recording. Im not holding out too much hope to be honest as I remember testing the resistance of these coils 2 weeks ago when the bike was running and it read in the mid 300s then.

As it is I am getting a fantastic big blue spark when I pull the spark plug cap off and earth the spark lead ... which I would presume confirms the state of the coils as being good.

when I try to start the bike it turns over fine and every so often it makes to start - spark and fuel combine but it never catches on to run the engine .. and then I have to keep turning the engine over for another few seconds where it repeats the same action ...

will let you know how i get on in anyways

cheers

f

[fward]

woohoo ... sort of
picked up the stator, ignition coils reading 170ohms now instead of 370 and the bike started first time from a jump start off a car. Not perfect running, this 'missing' in the engine ... (i can only describe it as a being like a 4 cylinder engine running off 2 or 3 cylinders) persisted.
I then took off the crankcase cover and proceeded to reposition the pulser unit which for some reason has many possible positions of placement (why is this?? why is there such latitude in where you can fix the bloody thing!!)

Too far forward and therefore close to the stator and the thing wont start at all, too far back dito. Eventually found a position where it starts and runs 90 percent from cold. I am still getting a miss in high revs, most noticable in second gear for some reason.

Does anybody know the best test procedure for positioning the pickups? I had an electrician once put a tiny dab of silicone on the two trigger points on the outside of the rotor; refit the stator and cover and then turn the crank a few times by hand before removing the cover to see if the pulsers/pickups had rubbed off the very top of the silicone. How close should they be, anybody got the figures??

Anyways I am over the moon that it starts again it sounds like a tractor on steroids but boy it starts. ... although I have to try it in the morning ... my arch enemy - the morning start ...

............. heres hoping