1983 XJ900RK

Hello all,
I've been rebuilding this baby for two years now. She was neglected, but had all her parts.
I cleaned the carbs, and she fired up.
I then took her apart to replace bearings, put her back together, and now she wont start. No spark.
I've found lots of helpful info here for this project, and am totally stumped as to how I should approach a diagnosis of what the matter may be.
Any suggestions would be welcomed.
Thanks

 

Sometimes you miss an otherwise simple problem.

One of the Switches having to do with the Safety Circuit is closed.
Most likely, ... Sidestand!

See that the Activating Rod atop the Sidestand Pivot isn't Crud-Bound; not allowing the Rod to move forward in the Small Bore near the Pivot.

Shoot the Switch Clean with SAFE Electrical Cleaner -or- Rubbing Alcohol.

With the Rubbing Alcohol, ...
Remove Cap.
Puncture Seal with a Tooth Pick or Paper Clip.
Squeeze Bottle aiming stream into Switch Housing.

 

A safety circuit issue will keep the motor from turning over at all.

If the motor is turning over but there is no spark, the first suspect is a weak battery. The starter may be drawing all available current leaving nothing to fire the ignition.

 

I'm aware that its the little things that drives us nuts.
So I went over all connections with sandpaper.
Alas, spark in all four cylinders. No start. Fuel??
Thanks for input. I tried to post a pic, but it too large. Ill figure a way to take another that is a smaller file.

 

Proper wires to proper plugs from the coils? Do you have the coils plugged in correctly to the main wire harness? I'd look for the little things like that.

Check to see if you have the relay switches plugged into the right place in the electric box (blue pin to blue relay) sort of thing (i've done that before and it stumped me for a freakin' week).

Best of luck

 

Although this might not pertain to this problem; be aware that OEM Coils have a Shelf Life.
There are plenty of Posts where Members have encountered Ignition issues only to replace 30-year old Coils with DYNA's, and said the Bike runs tip top.

My 900 wen through 2 Brains and several Coils.
A pair I got off EBAY lasted the longest; they arrived clean.
A pair I got gouged-for at a nearby Used Parts and Motorcycle Salvage Store (Junk Yard) bit the dust after a few thousand miles.

If you even suspect that your Coils are to blame, ... upgrade.

 

I'd look at fuel first, if you already know you have spark. Did you hook up the vacuum line to the petcock? Is there gas in the tank? Do you have fuel in the bowls? Did you try a snort of starting fluid?

Let's begin with that..............
dave

 

Make sure you fill the connectors with dielectric grease, because sandpaper probably stripped the factory tin-coating and corrosion will be a problem.

 

I'm a newbie to motorcycles, but a few things I had problems with that kept my bike from starting were:

air leaks from loose rubber intake boots-- make sure there is no extra air flying in;
a weak battery-- get it fully charged;
and of course making sure the bike is in neutral/on position with the kickstand up.

 

I may have more than one issue.
So: Push start button - nothing (actually oil light on dash comes on)
Use screwdriver on relay. - turns but no start
drained battery
check start button for continuity
check stop switch
check starter relay
check starter
:?

 

If the "oil" light comes on when you mash the starter button then it does mean that the safety circiit is "deployed."

Check sidestand switch; check neutral switch if the green "neutral" light isn't on when the bike is in neutral.

 

Perform a "Pop / No Pop" test.

Give it a good whiff of Starting Fluid.
Try her.
If she pops: Your issue is Fuel Supply.

No Pop: Likely Ignition relalted.

 

I thank evaryone for their reply, and all suggestions are heeded.
I went over the bike, and it seems that the carb is sending fuel into the oil pan. I researched this, and thankfully found alot of information on the Mikuni carbs.
Ive cleaned the carbs again, changed the oil, and hopefully she will start.
This project has brought lots of challages, and provided invaluable personal gratification.
Again, Thanks to all.
Cheers

 

Hey there !
Here's the starter circuit diagnosis thread.

http://www.xjbikes.com/Forums/viewtopic ... relay.html

also - - search "Church of Clean" and "Whole Nine Yards" - - this site.

Brake and tire warnings \/

 

Also, if you are trying to start the bike in gear.... check your clutch switch (on the handlebars) too. it may have worked its way out....

 

Also, I'd like to get your 900rk registered on the xj900rk Seca Database for USA-Delivered bikes. Please PM me.

Right now we're a little over 65 listed (two just came in in the last couple of weeks)!

Dave Fox