XS650D Ignition Timing Stuck

zoomoto

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Hey fam,

What i thought was a lean fuel mixture on my far side cylinder turned out to be an interesting ignition timing issue.

Regardless of how I rotate and set my bottom points plate, the point of spark will not change from this general area (see picture).

This is my first time digging into my bike’s ignition system and feel like I have done everything correctly based on my Clymer Manual. I have even started the whole process over again at timing chain tension. No change.

I plan on going to electronic ignition over winter but really want to learn how to work on the points system.

Any ideas? Currently blanking.

I have minimal play on my ignition shaft, cleaned the lobe, cleaned the fiber pads, filed the points (still some minor contact cratering).

Thanks for continuing to be an awesome community!
 
Uh thats not the points plate....its charging rotor and stator. Up above under the cover above the spark plug at the end of the camshaft. Try there.
 
Uh thats not the points plate....its charging rotor and stator. Up above under the cover above the spark plug at the end of the camshaft. Try there.

Appreciate the bluntness, however, the picture is only to show at what point in the engine's travel it is sending spark to the plug regardless of how the points plate is adjusted. Make sense? its weird.
 
Even if you can't get the timing dialed in exactly, changes to the points plate position should still show a change to where it fires. Let me ask the obvious - you are testing with the timing light connected to the left cylinder plug wire, or if static timing, with the test lamp connected to the lower left cylinder points set, right? You have to think of this as two little separate ignition systems here, one for each cylinder. You have to set and test each one individually.

Points ignition timing is a combination of the plate setting and the points gap. You may need to fool with the points gap to get the timing right. You look to be firing too far advanced. If you close the points gap up some, that will retard the timing a little for you. With used points that have some pitting, it's best to set them near or at the smaller gap in the speced gap range. The spark actually jumps between the pits, and you can't measure that gap with a feeler gauge. The actual gap ends up being bigger than what you're measuring.
 
Even if you can't get the timing dialed in exactly, changes to the points plate position should still show a change to where it fires. Let me ask the obvious - you are testing with the timing light connected to the left cylinder plug wire, or if static timing, with the test lamp connected to the lower left cylinder points set, right? You have to think of this as two little separate ignition systems here, one for each cylinder. You have to set and test each one individually.

Points ignition timing is a combination of the plate setting and the points gap. You may need to fool with the points gap to get the timing right. You look to be firing too far advanced. If you close the points gap up some, that will retard the timing a little for you. With used points that have some pitting, it's best to set them near or at the smaller gap in the speced gap range. The spark actually jumps between the pits, and you can't measure that gap with a feeler gauge. The actual gap ends up being bigger than what you're measuring.

I’ll have to play with the gap then. That makes perfect sense. I took the points, plate, etc. all off for a good cleaning and a re-lube. Do you have a favorite lube/grease for the lobe? It was pretty dry in there.

Yes, when setting my static timing I am using a light. Ground clip to engine fin and hot wire to corresponding points set which in this case is the lower set.

I’ll have time to play with it in the next few days. Thanks for the help
 
I use an actual points cam grease, not too easy to find today. I got a tube for my BMWs many years ago (Bosch brand) but I don't think it's available any more. I also bought a tube from a Harley shop. It was very old when I bought it (had "AMF" on the label, lol), so I doubt that's available now either. Both are a very thick, "dry" grease, like a paste. I think the Yamaha manuals call for a couple drops of 30wt. oil on the felt pads. Pretty much anything will work, but use sparingly.
 
Appreciate the bluntness, however, the picture is only to show at what point in the engine's travel it is sending spark to the plug regardless of how the points plate is adjusted. Make sense? its weird.

Sorry zoomoto sometimes questions are asked on parts unknown to them. I understand your concern now.
 
Another great write up by the master, hahah. Thanks guys. Looks like I have a first gen points set up on my 77? Will confirm shortly.

No worries, Superjet. I am admittedly newer to this bike so i wouldn’t put it past me. Appreciate your time.
 
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Alright. So. I was wrong i do have the correct components for ignition.

I reassembled everything but for some reason I am not getting spark at all. My light will go off when I touch certain parts of the plate so I know it’s getting power.

Potential newb mistake? I’m unsure. I even rearranged the order of washers on the electrical inputs on points, hahah.

Need to buy new charger so maybe I’ll do that. Battery should be fine though.
 
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Here is what it looked like before hand. I trimmed the felt and scooted them forward, cleaned the lobe, filed the points (not sure how sensitive they are to that??).
 
On your 1st pic, the points gap looks rather large. If it's too big, the points will never close. The test light comes on when the points open, goes out when they close. The coil charges up for the next spark when the points are closed. If they never close, that won't happen and you won't get a next spark. If the feeler gauge you used had any oil on the blade, that can contaminate the points faces and they might not make contact when closed. Hook up your test light and turn the engine over a few times. Watch for the light to go on and off. That will tell you whether the points are opening and closing correctly, making and breaking contact. If the light never goes off, the points aren't closing correctly. The gap could be too big, the points faces might be contaminated, or the points may be worn out. The spring steel strap that snaps the points closed can weaken with age and then the points won't close properly. That's why points should be changed about every 10 to 15K miles even if they still look OK.
 
On your 1st pic, the points gap looks rather large. If it's too big, the points will never close. The test light comes on when the points open, goes out when they close. The coil charges up for the next spark when the points are closed. If they never close, that won't happen and you won't get a next spark. If the feeler gauge you used had any oil on the blade, that can contaminate the points faces and they might not make contact when closed. Hook up your test light and turn the engine over a few times. Watch for the light to go on and off. That will tell you whether the points are opening and closing correctly, making and breaking contact. If the light never goes off, the points aren't closing correctly. The gap could be too big, the points faces might be contaminated, or the points may be worn out. The spring steel strap that snaps the points closed can weaken with age and then the points won't close properly. That's why points should be changed about every 10 to 15K miles even if they still look OK.
I’ll check the gaps when I get home. I feel the tension on the strap is fairly weakend with a little too much easy movement right off of point contact.

I also know for a fact that I had oil on my feeler gauge. I’ll clean that up too.

Is there a good place to find second generation ignition points on the web? Mikes has first gen only at first glance.
 
I'm pretty sure Mike's points are "2nd Gen", or at least they used to be. I think that's all that's made now. But you can do better elsewhere if you know what to look for. This will save you a good $10, and it's the exact same part .....

https://www.ebay.com/itm/Yamaha-75-...ash=item3636741a20:g:F6sAAOSwXSRbQ3ef&vxp=mtr

And here's a "or best offer" auction that might save you even more. Offer them $12 for 2 sets, maybe they'll accept .....

https://www.ebay.com/itm/NOS-Yamaha...tem2f2218a6d0:g:eaoAAOSwcW9bmci7&vxp=mtr#shId
 
I'm pretty sure Mike's points are "2nd Gen", or at least they used to be. I think that's all that's made now. But you can do better elsewhere if you know what to look for. This will save you a good $10, and it's the exact same part .....

https://www.ebay.com/itm/Yamaha-75-...ash=item3636741a20:g:F6sAAOSwXSRbQ3ef&vxp=mtr

And here's a "or best offer" auction that might save you even more. Offer them $12 for 2 sets, maybe they'll accept .....

https://www.ebay.com/itm/NOS-Yamaha...tem2f2218a6d0:g:eaoAAOSwcW9bmci7&vxp=mtr#shId


Okay! Got the bike running! Points are definitely the issue. Cleaned them and have new ones on the way.

Another weird thing is happening now though. The bike will get stuck at 3000rpm at rev and not come back down?? Advance issue?

It will idle at 900 and I’ll try to give it a little more air with the idle screw and it will just stay at that engine speed and then suddenly jump way up to 1500.
 
The random dying could be the bad points. Weak springs may not be closing them every time like they should. You lose spark and the bike dies. Yes, the hanging high RPMs could be an advance issue. The advance unit and, more importantly, the advance rod that runs through the head need to be kept lubed. If you've never serviced these items, there's a good chance no one else has either since the bike was assembled at the factory, lol.

Pull the little chrome cover off to expose the advance unit on the right side of the head. Grab the 10mm nut in the middle (it's threaded on the advance rod) and twist it by hand. This will turn the rod and push the advance unit into the advanced position. Let go of the nut and the unit should snap back smartly to the retarded position. If it doesn't, the advance rod is all dried out and needs to be greased.
 
Alright I will spend some time and go through the advance unit. At first glance it seems to be functioning very well. Does not look original.

I double checked my timing and my bottom points set was firing intermittently. Pulled it had to bend one side so the points had better contact, reassembled and rev hang went away.

Now the far piston is combusting intermittently even though coil is firing. Tested on the bottom set of points and at the spark plug wire to see if spark was being sent. All seems to look fine.

Wondering if it’s a carb problem? I went one step richer to try and fix a stumble off of throttle and have left it on the bottom setting (one down from stock setting).

Maybe I reassembled wrong??? Wife is outta town on business next week so I’m need to get this thing fixed ASAP and get some riding in!

Points come in next Monday
 
You may not get very far with tuning until you replace those points. I think they're throwing an intermittent wrench into the works. When you say you went one step richer, what do you mean? One step richer with what?
 
You may not get very far with tuning until you replace those points. I think they're throwing an intermittent wrench into the works. When you say you went one step richer, what do you mean? One step richer with what?

That may be very true. I’m just trying to figure out if there is anything else that i could have possibly done to cause this. I may just need to be content with waiting, hahah.

Sorry, I meant on the needle. I adjusted the clip to the bottom setting.
 
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