Trying to start for the first time.

[yamyam]

I purchased a NOT running '79 xs400f from a guy that told me he thinks its the carbs for the reason its not running. The same guy also told me the bike was an '83 so Im not to sure what to believe.

Before I spend any more money than I have to to try and get this bike running when I have no idea if it's even worth keeping I was wondering what you guys would suggest in terms of getting her going.

So far i've.....
-changed the oil.
-drained old fuel and cleaned fuel tank.
-installed new battery.

Anything else before the first attempt, like a carb cleaner that doesnt involve taking them apart. any suggestions are greatly appreciated.

Peter

 

[l4ne4]

Take the carbs apart and cleeeeeeean. Check spark too.

 

[Lupe]

I would
- open the carbs and check if the diaphragms are ok and the inside of the float bowl is clean.
- take the spark plugs out and check if there are sparks (maybe renew them...)
- check valve clearance
- ignition timing

 

[yamyam]

So I got the bike running today with out any carb work or cleaning. The reason for not trying to start it earlier on was because of some wiring issues and not having power at the ignition. Fixed the wiring issue so decided to try and fire it up for the hell of it before getting into things to deep to see what happens.... It fired up within about 3 seconds of holding the electric start which was awesome and very unexpected.

Right now the problem is it idles at 5000 rpm and when I pull the choke out a bit while running the idle drops down to about 4000 rpm. I disconnected the thottle cable to see if that was causing the high idle but it's not. Any ideas on whats going on?

Thanks
Peter

 

[vectra]

get a can of starter fluid and try spraying it around the boots that hold the carb to the motor when its running
if the revs go up your best bet will be replace the boots
i got mine for around $35 on ebay
if it stays the same try the air intake side

 

[xschris]

Are you running any air filters on it? If not you are pulling too much air and its running lean.