In need of guidance! Xj650

Can I get a pic of your caliper? I want to confirm that I'm thinking of the correct one.

 

Sure thing. There's two of them one for each caliper. They came off last night and I'm not sure how

 

Thanks for all your help everyone. I got the calipers on. Simple as can be. I was complicating everything. I need to learn to not stay up all night working on it because that's what makes me start to go insane. I'll wait until the hurricane passes to work on changing that rear tire.

 

She's coming along...

Without xjbikes, I never would have attempted fixing this bike up.

 

Everything was running perfect until today when taking it out it started backfiring about 100 feet from my house so I turned around and it barely ran it was popping so much. Starts right up, just pops almost constantly. Acts extremely lean but dies with even a slight amount of choke. This bike has been nothing short of an emotional rollercoaster. Any ideas?

 

Weird. I had no idea Kmoe. She starts without enrichment every time because in fact if I do use any choke it kills the engine almost immediately. The only thing I can think of is my plugs are misfiring because they're fouled. I just bought these the other day too. Right now in the process of fishing out old orings from the pilot screws cause I forgot about those. Thinking I might need to just get new plugs, make sure I'm lean and adjust from there so I'm not fouling anymore plugs. Could fouled plugs really cause misfire/popping?

 

Also no , come to think of it I did not warm it up prior to riding it.

 

Misfiring is usually down to plugs or leads - remove plugs and check that all plugs they are all the same colour on the central electrode - any that are black will show the problem one.
Check usual things ;-
1. That all are sparking out-side the cylinder by attaching to leads and turning the bike over on the starter
2. Check resistance of each spark plug should be around 4100-6000 ohms
3. screw on plug caps firmly
4 check coil primary and secondary resistances
5 swap over plug leads from 2 to 3 and those from 1 to 4 if the lead from the coil is suspect

good luck!

 

It sounds to me like the idle mixture is a tad rich. Going by the weather reports, it's not been warm enough there for the engine to start without using enrichment if the idle mixture is set right.

 

You know what I find my strange, #1&4 are coming from the left coil, #2&3 from the right coil (correct I think). However, #1 cap is taiko denso, #2 is td134, #3 is taiko denso, and #4 is td134. I always thought the outers were both supposed to be td134 and the inners taiko denso.

 

Brand aside, the inner plugs should have the longer plug caps on them. So long as the resistances are correct they will work no matter the brand or style, the difference is for accessability (as noted by how the #2 plug cap barely fits, and is allowing the wire to touch the head).

The plug wires are coming from the correct coils, per your description.

You might want to start the machine in the dark, and maybe spray the plug wires down with water from a spray-bottle, to rule out cracked plug wires causing spark to jump to ground before reaching the plugs.

I'm still of the mind that this is an idle mixture issue, but testing for cracked plug wires is easy enough to do, and may be contributing to the problem (and I could also be wrong, so test, test, test).

 

I think you're right because I had to replace an oring on one of the mixture screws. Also all the plugs were soot fouled.

 

Okay, ran through the carbs real good one more time. Set the pilots 1 full turn out, fired her up with new plugs, and everything worked out great. Took her for a spin. Let her cool, pulled the plugs... Just a tad white. I guess from here its gonna be fine tuning everything. I suppose it was just a rich condition fouling the plugs. Thanks again everyone

 

Update: all 3 plugs except #2 look just like they should with the pilot screws only out one turn. #2 looks pretty black. And it only so happens that carb#2 is the one with the broken choke plunger. So my question is this: could a broken choke plunger (in the picture) cause a rich condition?

 

Answer is no. The enrichment plunger is closed by the spring in the assembly. The broken top means that it's always closed.

The big question I have is why you can start the bike with the idle mixture set to only one turn out from seated. With stock jetting the baseline is two turns out, and a bump or three beyond that to get them dialed in.

 

Hi all, I've got her rolling new tires and all. Been riding her for months with no issues. Loving the motorcycle it's really fast and sounds great. Had an issue getting the master cylinder screws out and have it all sorted now. been looking into an airbox because I'm stuck with pods for now. Any idea where I could get an airbox for a 1983 xj650 Maxim? Also, would installation involve breaking the frame apart or is it pretty easy? Thank you

 

pull carbs and starter a little heat on box whereit hits