I would make sure the points/timing and valves are set correctly. 2 1/2 turns out on the idle mix screws is a lot for these type carbs. You said you are running pods. What type are you using and what jets are in the carbs and where is you jet needle set at. Have you set the floats to the proper height? Have you synced the carbs with a manometer yet? Post some pics of the bike.
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Engine randomly dying
- Thread starter jonjkim12
- Start date
jonjkim12
'77 XS360 Owner
O boy,
ya i know 1 1/2 is the factory setting, but it was sputtering at that setting, i possible had the throttle screw (plastic white screw, please correct me if i'm using the wrong term) too high before setting the mix screws. I'll re-do it this week end.
As for the pods, i'm not sure it was installed by the PO. I have no experience with carbs, and haven't dug into it yet out of fear it won't run and then won't be able to bring to a shop haha.
i haven'y synced the carbs yet, but i'm working on making a little manometer for the weekend.
it sounds like you may not agree its the timing alone? there is some abnormal vibration in 3rd gear that i feel may be the carbs out of sync?
ya i know 1 1/2 is the factory setting, but it was sputtering at that setting, i possible had the throttle screw (plastic white screw, please correct me if i'm using the wrong term) too high before setting the mix screws. I'll re-do it this week end.
As for the pods, i'm not sure it was installed by the PO. I have no experience with carbs, and haven't dug into it yet out of fear it won't run and then won't be able to bring to a shop haha.
i haven'y synced the carbs yet, but i'm working on making a little manometer for the weekend.
it sounds like you may not agree its the timing alone? there is some abnormal vibration in 3rd gear that i feel may be the carbs out of sync?
jonjkim12
'77 XS360 Owner
Hey guys,
brought the bike to a mechanic buddy who's really good with bikes. He said he think its a lot simpler than i thought, and said it's probably the fuel filter just getting clogged. He said this because of how it dies while i'm riding. He said that it's like getting clogged, the breaking up over night which is why it rides fine again the next day, and clogs again. which also explains why when i really open the throttle, it tends to die more consistently.
any suggestions on fuel filters? i want to try this simple solution before getting too into anything else.
brought the bike to a mechanic buddy who's really good with bikes. He said he think its a lot simpler than i thought, and said it's probably the fuel filter just getting clogged. He said this because of how it dies while i'm riding. He said that it's like getting clogged, the breaking up over night which is why it rides fine again the next day, and clogs again. which also explains why when i really open the throttle, it tends to die more consistently.
any suggestions on fuel filters? i want to try this simple solution before getting too into anything else.
If he's right, it sounds like maybe the filter is installed in reverse - assuming you have a transparent filter.
They work both ways, however, if it's on backwards, the detritus accumulates inside where you can't see it. Installed the other way, the detritus accumulates on the outside of the filter screen where you can see it and judge when it's time to get a new one.
I've used the < $3 plastic ones with a fine metal screen.
Some folks on here prefer the ones with the paper filter element since it catches nearly every particle.
jonjkim12
'77 XS360 Owner
O wow really?
A bike can ride with that filter on backwards? I have one of these
http://www.knfilters.com/search/product.aspx?Prod=81-0221
And it looks like it goes from big to small from the tank to the carbs.
Even if it's one correctly I want to get a new ones. I'd like to get one that catches the most since this is a pretty annoying problem.
Papers catch the most? I was a little confused reading about it here on the forums. As for the size 1/4 or 5/16, is there any way for me to know what size aside from just measuring it?
Specific brand suggestions would be great if possible. Thanks for the reply!
A bike can ride with that filter on backwards? I have one of these
http://www.knfilters.com/search/product.aspx?Prod=81-0221
And it looks like it goes from big to small from the tank to the carbs.
Even if it's one correctly I want to get a new ones. I'd like to get one that catches the most since this is a pretty annoying problem.
Papers catch the most? I was a little confused reading about it here on the forums. As for the size 1/4 or 5/16, is there any way for me to know what size aside from just measuring it?
Specific brand suggestions would be great if possible. Thanks for the reply!
Sounds backwards. With luck it will be plugged solid and your problem will go away after you spend $3. No need for fancy brands, just what a lawnmower dealer sells.
Here's a good thread:
Here's a good thread:
jonjkim12
'77 XS360 Owner
haha that's embarassing for my mechanic and myself, if it is.
thanks Lou!, i'll let you know how it goes.
Also i've been trying to get pictures up here of my bike, since i think visually she's much better looking than how her engine runs, but i can't seem to get it uploaded, anyone know how to do this? i tried using the "insert image" button with a link to my flickr account, but it never works.
thanks Lou!, i'll let you know how it goes.
Also i've been trying to get pictures up here of my bike, since i think visually she's much better looking than how her engine runs, but i can't seem to get it uploaded, anyone know how to do this? i tried using the "insert image" button with a link to my flickr account, but it never works.
They usually have the pointy end facing the tank.
You can click "Go Advanced" and then use the paper clip icon.
You can click "Go Advanced" and then use the paper clip icon.
jonjkim12
'77 XS360 Owner
Need a picture of that clogged fuel filter ... 
jonjkim12
'77 XS360 Owner
jonjkim12
'77 XS360 Owner
i believe i have a vacuum petcock, if i want to swap it for a new one, how do I shut off the gas line is gas doesn't spill everywhere? anything to keep in mind while i do this?
also how do i find out what size fuel filter i need?
Edit: I have a vacuum line I think, (no "off" position?)
also how do i find out what size fuel filter i need?
Edit: I have a vacuum line I think, (no "off" position?)
Last edited:
if the petcock is working right....
Now the trick I have been doing lately is fuel tank positioning. (it is not a new trick, technically)
I have been using a ladder and a 4 foot hose for my carb balancing act. what I have found to work so that I don't get fuel all over the place, even thou its not much, etc...
is that when I plug my tank into the carbs, I do it with the fuel tank on the ground (on a 4"x6"x3.5' or so. Then when the fuel tank is plugged in, I will move the fuel tank and 4x6 to the top of the ladder (saw horse, whatever you got that is higher than the carb) Then put the petcock on Pri (prime=free flow of fuel).
To reverse it,
So what do you do if you dont have a working petcock? get a cheap fuel shutoff, plug that end with an inch or two from the petcock, then run everything like above. (borrow one from your snow thrower, you wont need it anytime soon!)
PS, I could tell from where your sending your msg's from. when you are able, click on the control panel, and leave a signature info for us, so we don't have to guess. Thanks for all I know it may never snows where you live.
- just leave the petcock in on/reserve mode.
- pull rubber hose off of petcock
- take vacuum hose off of intake boot
- take fuel tank off of bike
Now the trick I have been doing lately is fuel tank positioning. (it is not a new trick, technically)
I have been using a ladder and a 4 foot hose for my carb balancing act. what I have found to work so that I don't get fuel all over the place, even thou its not much, etc...
is that when I plug my tank into the carbs, I do it with the fuel tank on the ground (on a 4"x6"x3.5' or so. Then when the fuel tank is plugged in, I will move the fuel tank and 4x6 to the top of the ladder (saw horse, whatever you got that is higher than the carb) Then put the petcock on Pri (prime=free flow of fuel).
To reverse it,
- put the tank on the ground,
- turn the petcock to on/reserve,
- unplug fuel line at the carb,
- unplug fuel line at the petcock,
So what do you do if you dont have a working petcock? get a cheap fuel shutoff, plug that end with an inch or two from the petcock, then run everything like above. (borrow one from your snow thrower, you wont need it anytime soon!)
most of the fuel filters are dual size then you can snip off what you don't need. If you can go into any motor bike dealer, you will find a display, and they will sell you one. or your take your existing hose to a hardware store, small engine rebuilding shop, and see what they have that will fit your hose. Generally you should find something at a Lowes/Menards/Fleetfarm/Yamaha/Kawasaki store. Remember Yamaha makes boat motors too, and they have full access to everything OEM that currently available. If that is all you can find. you know what I mean?
PS, I could tell from where your sending your msg's from. when you are able, click on the control panel, and leave a signature info for us, so we don't have to guess. Thanks for all I know it may never snows where you live.
DARKMIDKNIGHTWARRIOR
XS400 Addict
Bike looks great!
jonjkim12
'77 XS360 Owner
Thanks Arfstrom and Dark!
just an update. Yesterday had my mechanic buddy over, we went over the whole bike, and he thought all my problems were stemming from a loose battery connection, which we corrected. We also changed the spark plugs, and re did the mixture screw adjustments (2 turns out).
no dice though. I never got to her running long enough for the main engine shut off issue (sudden engine shut off at higher speeds). This time after about 15min, as i downshift i started to notice that as i pull in the clutch the engine struggles. if i engage it while downshifting quick enough, it'll be okay, but as soon as i get to 1st gear and pull in the clutch to stop, she dies.
again its the same pattern, after the first time (for the day) the engine dies, it'll happen consistently for the next +/- 5 min. but will start right back up, 1st kick. i've noticed she'll tend to idle pretty high everytime i kick her thereafter though.
The next few weeks, i'm going to change the fuel filter, and check the static timing. Any other suggestions, comments, etc? So far this has stumped my 50yr old mech buddy, and somehow not come up for my main mechanic. Let me know if you guys need any additional pictures,or additional details to help narrow down the possibilities.
fyi, brought the bike to the mechanics a few weeks ago where he said he cleaned the carbs and did a once over on it.
just an update. Yesterday had my mechanic buddy over, we went over the whole bike, and he thought all my problems were stemming from a loose battery connection, which we corrected. We also changed the spark plugs, and re did the mixture screw adjustments (2 turns out).
no dice though. I never got to her running long enough for the main engine shut off issue (sudden engine shut off at higher speeds). This time after about 15min, as i downshift i started to notice that as i pull in the clutch the engine struggles. if i engage it while downshifting quick enough, it'll be okay, but as soon as i get to 1st gear and pull in the clutch to stop, she dies.
again its the same pattern, after the first time (for the day) the engine dies, it'll happen consistently for the next +/- 5 min. but will start right back up, 1st kick. i've noticed she'll tend to idle pretty high everytime i kick her thereafter though.
The next few weeks, i'm going to change the fuel filter, and check the static timing. Any other suggestions, comments, etc? So far this has stumped my 50yr old mech buddy, and somehow not come up for my main mechanic. Let me know if you guys need any additional pictures,or additional details to help narrow down the possibilities.
fyi, brought the bike to the mechanics a few weeks ago where he said he cleaned the carbs and did a once over on it.
Attachments
Did you check if your bike has a safety switch which allows the bike to be started in gear but only with the clutch pulled in?
If so, have you confirmed that it's working properly and not shorting out or sending a false signal when the clutch is pulled in?
If so, have you confirmed that it's working properly and not shorting out or sending a false signal when the clutch is pulled in?
I still think this is a carb issue. Perhaps start with the Float check. Get a clear fuel line, a foot or so, and if your carb is setup with the screw on the bottom of the bowl, just attach the fuel line to it, and open up the screw. Fuel should be to the bottom of the bowl mating surfaces. (I had one float that was shot, but I dont remember what problems it created. I new I could take the carb apart, put it back together, then it would run. next morning, it wouldn't or it flooded the airfilter/piston chamber contaminating the oil. Check for fuel smells from your oil.
your battery isn't an OEM style. is it charged up all the way? can you put some sort of volt meter onto it, to see where the battery is before, during and after a drive? This would confirm your charging system is tops/or not.
Still screaming carb issue. Mine does this too, but its because i have the choke on. Now my bike will want to idle that high (4k or so) and sometimes it will come down.
What size jets do you have in your carb? did the owner kick up the jets, just cause of air filter upgrade? Jets sizes are stamped in the side of them.
jonjkim12
'77 XS360 Owner
Hey Lou and Arfstrom,
i'm going to try to get you those answers. Since my motorcycle knowledge is pretty limited, it going to take some sniffing around for me to find these answers. I have photos of the air filters attached.
i just took her out for a ride again, and the clutch problem seems to be worse, now within 5 min of riding when i pull in the clutch the engine is dying, and if i can get it engaged downshifting before it quits, it just struggles until it dies.
the two issues here seem separate. one is when it dies while cruising at higher speeds at high rpms, the other is when the clutch is pulled.
i recently changed the spark plugs, i gapped them according to the manual, but i'm going to check again. as for the first issue at higher speeds, that one stumps me.
what do i need to buy to check the battery?
i'm going to try to get you those answers. Since my motorcycle knowledge is pretty limited, it going to take some sniffing around for me to find these answers. I have photos of the air filters attached.
i just took her out for a ride again, and the clutch problem seems to be worse, now within 5 min of riding when i pull in the clutch the engine is dying, and if i can get it engaged downshifting before it quits, it just struggles until it dies.
the two issues here seem separate. one is when it dies while cruising at higher speeds at high rpms, the other is when the clutch is pulled.
i recently changed the spark plugs, i gapped them according to the manual, but i'm going to check again. as for the first issue at higher speeds, that one stumps me.
what do i need to buy to check the battery?
Attachments
jonjkim12
'77 XS360 Owner
@xschris i'm hopeless at all electrical work. there is something below the seat, about the same size as the battery (little bit thinner). i have a feeling that's what you're talking about. All my buddies think its an electrical thing, but no one knows what exactly it could be.
the clutch problems are recent, before that she ran great, besides the cutting out at higher speeds. now i can't even get her to the higher speeds with out the clutch killing the engine.
the clutch problems are recent, before that she ran great, besides the cutting out at higher speeds. now i can't even get her to the higher speeds with out the clutch killing the engine.
