my bike wont start need help

[moorishone]

Hello everyone. I have a 1978 yamaha xs400. I was riding about a week ago and it cut off on me while doing 65mph. I got it to start and it cut off again had to walk it home now it just won't start. Replaced the battery but, it still won't turn over. Check out the video. I need help

 

[xschris]

I don't see a video but it sounds like a grounding issue or fuse.

 

[Sesty]

i dont see a video either?

did the electronics come on after you replaced the battery?

 

[moorishone]

Ok sorry. It didn't download. But if you go to YouTube. The title of the video is "my xs400 won't work"

 

[moorishone]

 

[Sesty]

good think i watched more than the first ten seconds, cause i was going to say you probably need a gas tank....didnt see it off the side. maybe raise the tank up a bit to make sure gas is getting to the carbs?

 

[moorishone]

Yeah it was doing that before I removed the gas tank though

 

[xschris]

I would check for spark at the plugs and then do a compression test. If the plugs are wet with gas it's getting fuel.

 

[Recreateme]

You will probably have to go through the usual checklist, maybe varying the order since you know it died in action, so i would push the carbs and fuel tank to the back of the list, check your coils, check for spark, check for compression. It is probably a lose connection somewhere in the wiring that was vibrated loose and needs to be re-seated.

Put the battery on the charger and grab your multi-meter!

 

[Charles]

Did you wiggle your kill switch and try it again.

 

[moorishone]

I have checked the coils actually they are new/used had them tested they are good. I am getting spark from the plugs and compression is good. I changed all the fuses and played with the kill switch. I am lost

 

[willem]

you're getting spark but it won't turn over? that's magic..

I'm guessing you actually mean it's not firing (which is different from not turning over) and based on your observations, your carbs are the culprits. My guess is something's blocking a passage, and you need to clean it out.

Edit: sorry should have watched the vid first. Still, if it's not the spark it's a fuel delivery problem. Check if the float bowls are getting filled, and check if your plugs are wet after trying to start. If the bowls are empty, check the petcock and replace your inline fuel filter. If the plugs are wet and the bowls are full, it's a timing issue. But since you don't get it to fire at all, I expect it's not getting any fuel.

 

[moorishone]

Right it's not firing. I hope it's not the carbs they are brutal. Lol. I hope it's not the stator cause I can't find them

 

[Charles]

Video is blocked here at work, so sorry if this is in there, but have you shot some carb cleaner in the carbs to see if that causes it to fire up? If so, then you def know it's a fuel delivery problem.

 

[moorishone]

I have not sprayed anything in the carbs. Will try that now

 

[Scorpio1963]

Either your battery or starter is slow also,at least compared to my bike.Make sure your battery is fully charged.Spray some starting fluid and see what happens.

 

[AnzacPaul]

Either your battery or starter is slow also,at least compared to my bike.Make sure your battery is fully charged.Spray some starting fluid and see what happens.

Guy at the exhaust shop had to to do this with my bike yesterday, spray some aerostart to get it running. (needs full choke, no accelerator when cold )

 

[Recreateme]

Yeah that is strange, thats exactly what my bike sounds like, but mine eventually starts... However it takes forever when its cold.

I had a period where i thought something major was wrong, it was exactly like your video. So i bought new plugs, put them in and it started lol

I think the issue i had was i would put my plugs in, and right around the end they would feel tight, so i left them there, when in fact it was just a grimmy thread and i had to really twist them down to seat them all the way in. Initially i was off about a 1/4 turn or so but it made all the difference.

Try removing them, check the gap, clean them off and re seat, if not just buy new ones for 8$ gap those and tighten em down.

Its cheap but it might not be the carbs and this would save you a whole bunch of carb cleanings if it is the problem.

EDIT - also, try kicking it at full charge not the starter, maybe the starter is sucking voltage and giving you weak spark.

 

[AnzacPaul]

I think the issue i had was i would put my plugs in, and right around the end they would feel tight, so i left them there, when in fact it was just a grimmy thread and i had to really twist them down to seat them all the way in. Initially i was off about a 1/4 turn or so but it made all the difference.

Please be very careful if you do this. Many a person has overtightened/threaded there spark plugs causing many more tears.

 

[moorishone]

I just got new spark plugs have yet to replace them though.even when I try kicking it no luck. But will see after I change them