You can get close by setting a piston to top dead center and see if the timing mark on the rotor aligns with the "T" on the stator. That's only as good as your ability to set a piston to TDC by looking through the spark plug hole.
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Help save my trip! Bike doesn't run when warm
- Thread starter Bjorn
- Start date
Interesting Jim
I got a rewound rotor where the mark was off 1/3 of the turn or so
I think it was a clymer manual that had a picture of a wooden stick into the Sparkplug hole.
Going against the top of the Piston.
I used a small paintbrush shaft and spanner on the rotor nut for finding top dead center
Obviously setting ignition timing then needs to be done " By Ear " and moving a bit back and forth.
A method common in the old days on cars.
One can hear the change in sound of the motor and if off difficulties in starting with the kick.
To early it knocks more .To late -- quiet but with less throttle response and power.
Idling can be lower rpm if close to the right spot.
And engine stalling if off..
Jim perhaps can tell if this is dangerous.
I have done so before even with the TDC mark at the right spot.
I feel the carburetor jets and play in bearings is a factor.
It runs quieter if a title later. I have rich mixture.
And the wrong ignition setting can make it difficult to start.
Please
Dont take this as an advice since there is a risk involved .I just describe how I have done it.
Inspection of spark plugs is a thing to do.
I got a rewound rotor where the mark was off 1/3 of the turn or so
I think it was a clymer manual that had a picture of a wooden stick into the Sparkplug hole.
Going against the top of the Piston.
I used a small paintbrush shaft and spanner on the rotor nut for finding top dead center
Obviously setting ignition timing then needs to be done " By Ear " and moving a bit back and forth.
A method common in the old days on cars.
One can hear the change in sound of the motor and if off difficulties in starting with the kick.
To early it knocks more .To late -- quiet but with less throttle response and power.
Idling can be lower rpm if close to the right spot.
And engine stalling if off..
Jim perhaps can tell if this is dangerous.
I have done so before even with the TDC mark at the right spot.
I feel the carburetor jets and play in bearings is a factor.
It runs quieter if a title later. I have rich mixture.
And the wrong ignition setting can make it difficult to start.
Please
Dont take this as an advice since there is a risk involved .I just describe how I have done it.
Inspection of spark plugs is a thing to do.
Bjorn
XS650 Addict
I did a visual inspection, LH cylinder at TDC the mark was on the stripe. So I call it good for now.
Just did a testride with the new rotor and other reg rec.
...
...
Exactly 40minutes in, starts to stumble again. I can leave it running idle without it stalling. Revving it some times goes ok, and sometimes leads to more misfiring.
I popped the airfilters off, no difference
I removed the crank vent cannister, no difference.
I sprayed it with some deodorant around the intake barbs, hard to tell if something happens there. It's stumbling before I do it.
I'm throwing in the towel
Just did a testride with the new rotor and other reg rec.
...
...
Exactly 40minutes in, starts to stumble again. I can leave it running idle without it stalling. Revving it some times goes ok, and sometimes leads to more misfiring.
I popped the airfilters off, no difference
I removed the crank vent cannister, no difference.
I sprayed it with some deodorant around the intake barbs, hard to tell if something happens there. It's stumbling before I do it.
I'm throwing in the towel
No Sir -- We are here ..
Please list what you have done
As I understand it
Replaced Rotor
Checked stator < --------- !!! ..???
Replaced Regulator and Rectifier
Still have 14 V at start up ?
What is the Voltage reading after the 40 minutes ride .. high 12 - s ?
Is it jumping around ?
Does it misfire on one side or both.
Please check the connections to ignition box and coils 12 V there ? Ground ?
Are spark plugs new ? < --------- !!! ..???
Does something else flicker lights ? ( Ignition Lock ? faulty )
Engine kill Switch on handlebar ??
And fuse box so it is not sloppy holding the fuses.
And give name and type of ignition.
Boyer ignition has a fault finding process perhaps yours also have one.
Perhaps that company answers on e -mail ?
Most vendors have a technician that have seen all Problems before.
When did this starting to happen
Bjorn
XS650 Addict
Hi Jan,
Stator all 3 windings had around 0,5ohm no short to ground either
The charging is very strong, 14 at idle, the rest 14,5
Batt ign off after 40m 13.0v
It does seem like the rh cylinder is running out of sync compared to the lh.
Did a compression check now: both 135psi, warm with WOT
No kill switch on the bike
Fuses visually ok
New sparks plugs yes
Gonna try my old ign box. I know it doesn't advance but will see
Stator all 3 windings had around 0,5ohm no short to ground either
The charging is very strong, 14 at idle, the rest 14,5
Batt ign off after 40m 13.0v
It does seem like the rh cylinder is running out of sync compared to the lh.
Did a compression check now: both 135psi, warm with WOT
No kill switch on the bike
Fuses visually ok
New sparks plugs yes
Gonna try my old ign box. I know it doesn't advance but will see
Of the picture I can se that it is a Carmo I write to the company
My stock TCI box did the following. The cold bike would start one kick. I let it warm a bit then go ride. Once fulled warm, it would quit running normally and maybe drop to one cylinder. I could go maybe 45 mph at WOT and get hard surging. If I stopped the idle was just fine. Having the joints in the TCI box resoldered seems to have fixed it. Are you suffering similar?
Bjorn
XS650 Addict
I know what it is 99% sure. Just spoke to the guy at carmo who developed this ignition. Here is the thing:
It's using the pick up for signals. Because it's digital it's better at advancing the curve quickly. Downside is that it's more sensitive to a wrong pulse (long technical story)
Ones the bike heats up it affects the pick up. Just measured the resistance: 940 ohm each. Should be 700 at 20°c. Gonna remeasure when cold.
Just drove with the oem ign. No issues!!!
According to the guy this s because it's hardware is less sensitive to the difference in peaks of the signal.
Plan now: reinstall the oem TCI . It runs but doesn't advance good. So less top speed. But it's a runner!
It's using the pick up for signals. Because it's digital it's better at advancing the curve quickly. Downside is that it's more sensitive to a wrong pulse (long technical story)
Ones the bike heats up it affects the pick up. Just measured the resistance: 940 ohm each. Should be 700 at 20°c. Gonna remeasure when cold.
Just drove with the oem ign. No issues!!!
According to the guy this s because it's hardware is less sensitive to the difference in peaks of the signal.
Plan now: reinstall the oem TCI . It runs but doesn't advance good. So less top speed. But it's a runner!
Bjorn
XS650 Addict
So when the bike revs slow, one bad pulse is quite a lot and messes up the firing.
When revving hard, no problems because one bad pulse is now only a very minor part of the signals coming in
When revving hard, no problems because one bad pulse is now only a very minor part of the signals coming in
I Believe that is a No No
Perhaps it is not noticeable at higher revs but a ignition pulse to soon at higher revs can cause damage on the engine
" Engine Knocking "
But as it seems
We have support from the Manufacturer.
We have a solution provided the pickup is not faulty and works with the Stock Box..
I would use the stock ignition box.
But I suppose it is about riding style ,and preferences.
I experienced an issue with i believe worn brushes, creating iggy issues at certain rpms. I think this was false signals because of voltage spikes. New brushes, problem solved. Might want to open, check wiring by sprocket, broken wires happen there.
Bjorn
XS650 Addict
Just decided, I'm not taking the XS650 on the old-timer trip with the guys.
All the time working on the misfiring kept me from making A luggage rack, the fender is resonating itself to dead on the highway and the left carb just started leaking from the bowl. I don't have a spare gasket.
Guys I can't thank you enough. This will definitely get a follow up. For now, I'm gonna pack my other bike...
Not gonna lie, this feels terrible... All this effort, all this time and work
All the time working on the misfiring kept me from making A luggage rack, the fender is resonating itself to dead on the highway and the left carb just started leaking from the bowl. I don't have a spare gasket.
Guys I can't thank you enough. This will definitely get a follow up. For now, I'm gonna pack my other bike...
Not gonna lie, this feels terrible... All this effort, all this time and work
Once it all comes together, your grin will be ear to ear. It will be all the better because you made it so. For now, just enjoy the trip and post pictures in the appropriate thread.
It's good that you have another bike. Put it all behind you Bjorn and just enjoy your trip. When you get back, have a read here. @Team Junk has discovered that a Suzuki GN250 ignition box is most likely a viable replacement for the TCI box at a cost of about $20 here in the states. I'm running one in my 80SG and so far so good.
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Bjorn
XS650 Addict
Changed my mind, gonna be an adventure. Wish me luck
Yes Sir
Good Luck
There will always be something With these old bikes.making one nervous out there on the road.
Or something that could have been better newer etc etc leaking less
Tools water and other things needed ..on the trip --- Money for taxi home ... ??
But to me that is a part of the Hobby.
Man and Machine interface. It is something you do yourself.
It can be difficult and getting hands dirty.
But once you are out there in the wind so to speak
something has been Achieved.
A feat has been performed .. ..
Please keep us posted on how it goes on your trip Bjorn!
Pete
Pete
Bjorn
XS650 Addict
So we made it to Luxembourg! Don't ask me how. First few hours went great! But that after the first long stop it would start but just die because no spark. This would go on and off. Somehow it kept going but it makes me Hella nervous. Note that the tacho would keep working, so the system doesn't die complele
Higher speeds would go ok. But usually after stopping no Matter how short, it would act up.
The last few 20 km were nerve-wracking, I can tell the bike is not running good. It's not popping but I see the tacho vibrating. It didn't do that the first part of the trip. Note that it's a new tacho that uses inductive sensing of one plug wire.
I brought a shit load of tools and a backup reg rec. But that's it.
If anyone has some suggestions, I'm all ears!
My instinct says it either a wiring problem
Higher speeds would go ok. But usually after stopping no Matter how short, it would act up.
The last few 20 km were nerve-wracking, I can tell the bike is not running good. It's not popping but I see the tacho vibrating. It didn't do that the first part of the trip. Note that it's a new tacho that uses inductive sensing of one plug wire.
I brought a shit load of tools and a backup reg rec. But that's it.
If anyone has some suggestions, I'm all ears!
My instinct says it either a wiring problem
So if I am thinking out Loud here
Charging is new more or less . a couple of times .. should be OK charging 14 V
Ignition is the Stock known working box
The pickup can be Dodgy. measurement values.?
The voltmeter needle jumped around.
My first check would be the wires coming through to the Front lamp.. So the sharp edges of the lamp.
not has cut trough the insulation on wires.
Then I would Disconnect that jumping voltmeter for a while
Thinking out Loud here again
Since you have a later than 80 Alternator you probably have a couple of fuses 4 or 5.
One main 20 A the rest 10 A if I recall Right.It looks that way on the Pictures
Why not try find smaller Fuses Leave the 20 A and go down on the Others
A quick googling gives 7.5 A and 5 A should exist.
A gas station usually have some
If one fuse blows ..Information is Obtained. Not necessarily a proof ..but can be something to work on.
Lastly ,,this is perhaps stupid at this point in time ..but a leaking exhaust can also make misfiring sounds
A quick check of those bolts ...Wont Hurt.
Bjorn
XS650 Addict
I have measured the pick up hot and cold. Values are somewhat high with 850 ohms hot (2x) and 780 cold. Both wires give the same reading.
Before I left I disconnected the tacho when the bike was running weird, it didn't affect it. I checked the wiring in the headlight, it's fine and undamaged.
I got a modern fuseholder, I can try your suggestion with lower A Fuses.
And regarding the exhaust, I understand but this is electrical for sure. We checked the spark last time it died. We didn't see any sparks, but my friend did get zapped. Maybe it is or was sparking super weak.
Let's see what happens today. At least the view is nice
Before I left I disconnected the tacho when the bike was running weird, it didn't affect it. I checked the wiring in the headlight, it's fine and undamaged.
I got a modern fuseholder, I can try your suggestion with lower A Fuses.
And regarding the exhaust, I understand but this is electrical for sure. We checked the spark last time it died. We didn't see any sparks, but my friend did get zapped. Maybe it is or was sparking super weak.
Let's see what happens today. At least the view is nice
