While you are in there check to make sure you have 12v there also. The other thing to check is make sure the left petcock is flowing fuel. pull off the fuel line and open the tap with a cup to catch the fuel.
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need help with my '77 xs650 Not idling and blinkers stay solid
- Thread starter legendary yamaha
- Start date
The Tik Tik Tik sound you are describing. Could that possibly be an exhaust leak? At the head pipe maybe?
Yes, checking if the headpipe is hot is the simplest way to verify a cylinder is firing. Start it up, lick a finger and touch the pipe just for a second. If it's running, you'll sizzle the spit on your finger, that's how fast the pipe gets hot. And that's why you lick your finger. If you don't, you'll burn it.
do you have a Haynes workshop manual ? you'll need to get some sort of workshop manual if you intend to do this work yourself .
Have you looked in the TECH section at the top of every page ? it is organised in sections to make it easy to find relevant articles and guides.
This thread would be a good start to read through and use as a troubleshooting guide and information source. http://www.xs650.com/threads/bike-wont-start-running-rough.390/ much of it won't be relevant but it will give you a checklist to help with diagnosis. Note that Inxs recommends checking and proving everything else before tackling the carbs. This is good advice for those new owners that do not have a thorough understanding of these bikes.
If you wish to see which cylinder is not working put your hand in front of the end of the silencer and see which cylinder is not producing an even exhaust pressure pulse
First easy step would be to buy 2x new spark plugs and gap them to the correct gap and change out one plug at a time and check if that cures the problem. make sure that you always mark the plugs and keep them to the same cylinder . Your plugs will always tell you how well or not a cylinder is working.
If a new plug doesn't sort it then you will need to work your way back from the spark plug to the coils testing as you go. If you remove a spark plug , refit the plug cap and lead and hold the plug against a clean ground point with a pair of insulated pliers and turn the engine over you will be able to see if you have a spark or not on that cylinder
Have you looked in the TECH section at the top of every page ? it is organised in sections to make it easy to find relevant articles and guides.
This thread would be a good start to read through and use as a troubleshooting guide and information source. http://www.xs650.com/threads/bike-wont-start-running-rough.390/ much of it won't be relevant but it will give you a checklist to help with diagnosis. Note that Inxs recommends checking and proving everything else before tackling the carbs. This is good advice for those new owners that do not have a thorough understanding of these bikes.
If you wish to see which cylinder is not working put your hand in front of the end of the silencer and see which cylinder is not producing an even exhaust pressure pulse
First easy step would be to buy 2x new spark plugs and gap them to the correct gap and change out one plug at a time and check if that cures the problem. make sure that you always mark the plugs and keep them to the same cylinder . Your plugs will always tell you how well or not a cylinder is working.
If a new plug doesn't sort it then you will need to work your way back from the spark plug to the coils testing as you go. If you remove a spark plug , refit the plug cap and lead and hold the plug against a clean ground point with a pair of insulated pliers and turn the engine over you will be able to see if you have a spark or not on that cylinder
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I just re-read the whole thread from the first post and I really didn't really pay enough attention to what you said in your first post. 
As I understand it the engine was running fine until you randomly replaced the ATU springs
If after that work the engine started to give issues ...the ATU is where you need to concentrate your attention. The initial issue would have been something connected with the work you did on the ATU .
The tick tick noise is probably your ignition spark shorting out intermittently causing unburnt fuel to be dumped in the silencer and then when a spark does finally get through the fuel explodes in the silencer which is why you are getting flames out the can .
Get a handbook and open up your advance again and thoroughly check that everything is fitted correctly and there are no shorts to ground or pinched wires etc .I bet that is where the issue lies
As I understand it the engine was running fine until you randomly replaced the ATU springs
If after that work the engine started to give issues ...the ATU is where you need to concentrate your attention. The initial issue would have been something connected with the work you did on the ATU .
The tick tick noise is probably your ignition spark shorting out intermittently causing unburnt fuel to be dumped in the silencer and then when a spark does finally get through the fuel explodes in the silencer which is why you are getting flames out the can .
Get a handbook and open up your advance again and thoroughly check that everything is fitted correctly and there are no shorts to ground or pinched wires etc .I bet that is where the issue lies
You're not going to get it running right until you properly clamp that loose carb in place. It may have been stuck in there and sealed itself in before when the bike did run OK, but now you've pulled the carbs out and broken that seal. You also mentioned the butterfly plates aren't aligned or matched. That means the carbs are out of sync. One may be effectively shut off at idle if it's plate is completely closed.
legendary yamaha
IG:ne_caferacer_club
I ordered the Hayes service manual book today arrives after 4-5 days(hopefully)I just re-read the whole thread from the first post and I really didn't really pay enough attention to what you said in your first post.
As I understand it the engine was running fine until you randomly replaced the ATU springs
If after that work the engine started to give issues ...the ATU is where you need to concentrate your attention. The initial issue would have been something connected with the work you did on the ATU .
The tick tick noise is probably your ignition spark shorting out intermittently causing unburnt fuel to be dumped in the silencer and then when a spark does finally get through the fuel explodes in the silencer which is why you are getting flames out the can .
Get a handbook and open up your advance again and thoroughly check that everything is fitted correctly and there are no shorts to ground or pinched wires etc .I bet that is where the issue lies
Before I do anything I will check the wires under the gas tank, and the coil cables to see if electricity goes to both cilinders, and after I will deal with the start plugs and so on, was riding that vacum leak or ignition can cause the cilinder not to work so that might be the case. But will wait for the book before I do something stupid and make it worse.
legendary yamaha
IG:ne_caferacer_club
I bench set up the butterfly valves, so they both close in the same time, will do the test with WD-40 around the boots to check for leaks, was thinking to get a ‘fish’ can and place it under that clamp it will help to tighten it more, but is weird because the big clam is in the right cilinder not in the left one that is spitting fire. Can a clogged pilot jet make the bike run rich or cause a dead cilinder??
legendary yamaha
IG:ne_caferacer_club
Hopefully this one helps, is any way since I bought it, to put some pages from the book for the others here or is not allowed?
Attachments
A clogged pilot jet wouldn't make it run rich but could kill the cylinder at idle. Too bad you can't rev it up because if the dead cylinder kicked in when you did, that would indicate the pilot (low speed) circuit may be plugged.
legendary yamaha
IG:ne_caferacer_club
I didn't try to rev it hard enough because I was afraid it will break something, I will try to get someone get a video from the beginning of starting till shuts down.
There are factory service manuals online that you can download for free .....
https://thexscafedotcom.wordpress.com/category/manuals/manual-workshop/page/1/
Maybe they'll help.
https://thexscafedotcom.wordpress.com/category/manuals/manual-workshop/page/1/
Maybe they'll help.
It sounds like you are at an early point on the learning curve. Good idea to buy a manual and let that guide you. But a manual is best as a guide to stripping down and building up - less use at telling you what is causing a problem. Easy to go round in circles, blame the ignition system for carb faults. Or vice versa.
Priceless to have an experienced eye - or ear - spend half-an-hour with your bike and diagnose the problem. Failing that, this forum really is the next best thing. But you need to try and adopt a rational approach and not get too worried about breaking something or making matters worse. At the end of the day, everything mechanical can be fixed.
legendary yamaha
IG:ne_caferacer_club
Knowing how it’s built, maybe will help me to understand the condition if something is not like it should.
legendary yamaha
IG:ne_caferacer_club
Update:
Checked for leaks on the carb boots, they were good, not leaks, it holds on idle, I let it run for like 10 minutes, it started with poping and loud noise, but after 2 min no more, I checked for noise and if it had dead cilinder, both sides got hot and both exhausts were bringing air the same, so I let it run for like 10 min, and tried to put in gear. Here is the bad news, The second I was letting the clutch go, the bike start moving , I gave a little gas but the rev went up to 3k and a little more, shut it down, started again, was idling fine, put again in gear the same started rev at 3k.
Checked for leaks on the carb boots, they were good, not leaks, it holds on idle, I let it run for like 10 minutes, it started with poping and loud noise, but after 2 min no more, I checked for noise and if it had dead cilinder, both sides got hot and both exhausts were bringing air the same, so I let it run for like 10 min, and tried to put in gear. Here is the bad news, The second I was letting the clutch go, the bike start moving , I gave a little gas but the rev went up to 3k and a little more, shut it down, started again, was idling fine, put again in gear the same started rev at 3k.
Check the routing of your throttle cables. Drawings here somewhere. Do a search titles only throttle cables. At least your making progress. On to the next issues. Also look at lubing cables.
I'm not sure I understand what you're saying. Did it rev up to 3K and just hang or stick there, or did it stall? If you can't rev it up with the bike just sitting there in neutral and not moving, you're not going to be able to ride it yet, you still have some carb issues to sort out. It appears you have mods like pod filters and a different, probably freer flowing exhaust. That will most likely require some jet size changes to run right. The P.O. may have done some but maybe he didn't get it right yet. You should check the jetting you have in there now. Read the numbers off the jets and write them down. This brings us back to positively identifying your carb set year. Re-jetting is based on what was stock in your year carb set. Until you come through with a little more info for us, we can't help much.
legendary yamaha
IG:ne_caferacer_club
I will take a look at the cables but the throttle it’s not open when it revs at 3k, I was thinking something inside carbs, like the floats or the timing, when I let the throttle go, it takes some time to down, doesn’t cut right away. I might be wrong, not sure,
That could be those crap MikesXS advance springs you installed. They could be too weak and won't pull the advance weights back in to retard the timing. If the timing won't retard, the revs will hang.
legendary yamaha
IG:ne_caferacer_club
Info: it was idling fine after 2 min, set up at 1.2k for idling and it was good. When I rev without putting in gear it went down to 1200, when I put on gear and tried to move it rev up to 3k, and stuck there.
Shut down
Start again, idling fine.
Put on gear,
Rev to 3k and stays there.
