Hi everybody, I have a 1980 XS400 special. It seems that when the bike has been sitting, and gets cold started that I have to prime it. Is that normal or is that just a quirk with the bike. Myself and another guy could not find gas leak anywhere. Thanks alot, have a great day!
-
Enjoy XS400.com? Consider making a donation to help support the site.
XS400.com receives a small share of sales from some links on this page, but direct donations have a much greater impact on keeping this site going.
Priming when cold
- Thread starter zonk39
- Start date
63-Coupe
XS400 Addict
Gotta ask, no insult intended; Are you using the choke when you try to cold start it? 
Gotta ask, no insult intended; Are you using the choke when you try to cold start it?
Yes But it needs gas. After I prime it then it will start. If I don't prime it, it will take 20 kicks to start. Thanks alot, have a great day!
63-Coupe
XS400 Addict
The symptoms indicate that essentially you are dealing with a problem of not enough fuel in the carbs to start it. You say it is when cold starting after sitting so it could be that fuel has evaporated out of the carbs. If the bike has been sitting for a long time putting the petcock to the "PRIME" position to refill the carbs to start it is not in itself unusual. If it is after only overnight then yes there is likely something wrong.
Don't just look at the carbs as possibly being the culprit. Before you start ripping them apart make sure that they are getting fuel from the tank when you try to kick start it. I am thinking it's possible that you may have a partial vacuum line leak, or a partially plugged petcock or filter if you have one. Pull the fuel line off, when the petcock is set to "ON" or "RES" you should have no fuel flow when the engine is not running. When you kick the engine over you should get good fuel flow. Full unrestricted flow should only happen when the petcock is set to "PRIME".
Don't just look at the carbs as possibly being the culprit. Before you start ripping them apart make sure that they are getting fuel from the tank when you try to kick start it. I am thinking it's possible that you may have a partial vacuum line leak, or a partially plugged petcock or filter if you have one. Pull the fuel line off, when the petcock is set to "ON" or "RES" you should have no fuel flow when the engine is not running. When you kick the engine over you should get good fuel flow. Full unrestricted flow should only happen when the petcock is set to "PRIME".
I always prime the carbs before I start the bikes. Even if I not going to run them I make sure the carbs have fuel in them once a week. This will keep them from getting any dried up gas gunk in them and also keep any rubber bits wet and soft.
I understand the question now.
normally to prime an engine you tickle the carbs and kick over a few times, run it over TDC before ignition is switched on and then kick start it.
your talking about the Petcock setting to prime ^^ what they said^^
normally to prime an engine you tickle the carbs and kick over a few times, run it over TDC before ignition is switched on and then kick start it.
your talking about the Petcock setting to prime ^^ what they said^^
danisawesome
XS400 Addict
I prime it every time then one kick and ride
Going to try this next time; usually it takes 3 kicks when cold, so maybe this will get it down to 1.
I prime it every time then one kick and ride
I just did that this am and you are right 1 kick. Have a great day!
