XJ650 Seca Seized Engine Help

idle adjuster would be setto where the butterfly on # 3 was just showing the 1st pilot circuit hole in the top of the carb throat, this would have been done at bench sync.

 

Idle speed screw initial setting:
Coarse thread: 1.5 turns out
Fine thread: 2.5 turns out

Sounds like circuits may be clogged in a carb yet-----Or some jets in the wrong places.

Butterflies - I'd check to make sure that all the butterflies are even:

Turn the idle speed screw BACK so it's not touching anything

Put the straightened end of a paper clip under 'fly #3... let the fly hold the clip in place.

• If it's too loose and the 'fly isn't holding it, you have another waaay out of adjustment. So, play with appropriate screw to open THAT fly more, etc.... til you get just fly three holding that paper clip.

NOW-get another paper clip of the same size, open the end, and adjust each of the three remaining 'flies until you get the same firmness of 'pinched clip' at all four butterflies.

Remove the clips and let the buuterflies close.

Turn the idle screw in until 'fly #3 opened enough for the first hole at the top to be half covered.

Adjust the sync screws so the other three are the same way.

Snap the lineage open and shut a few times

Check and adjust screws if needed

Now you're ready to install try again.

Keep us posted, feel free to send me a conversation if you need specific help.

dave

 

If only there were some one here who knew everything about these carbs... I'd make that guy a moderator!

 

I did a thorough bench sync when they were off the bike but I bet after stuffing around with the idle speed screw, they're probably out again now? Time to pull them off again.

hogfiddles - I'll double check the circuits. They were clean but I wonder if something got back in there. Jets are in the right places but a double check won't hurt and I'll post the results here to make sure.

MattiThundrrr - those mods are wise men aren't they? ;-)

 

The idle speed screw will not affect the synch screws. It's not a bad idea to re-check the bench synch though.

 

Alrighty, so today I pulled the rack again and ran through your valuable checks. Air jets are standard and in the correct positions. I checked all the sliders for the "clunk" test and they're good. Pulled apart all the idle mixture screws/springs/washers/o-rings and there was a bit of crud in a couple of them, so I am cleaning that out. This is new so I'm a bit concerned and will strip the float bowls again to clean everything up. It looked like white crusty build up. I'll also put a another new filter in place just to make sure.

While I was at it, I made up a mixture of rubbing alcohol and wintergreen oil to soften the boots and manifold rubbers per this article : http://v4musclebike.com/forums/showthread.php?t=13477 . Will let you know what the outcome is.

...and I ripped out my battery negative terminal lead and made a new one. The old terminal connector had bitten the dust ages ago and a bent standard terminal just wasn't cutting it, so I made a new one up from some scrap metal I had. Will take a photo when I'm out there next.

 

Boots and manifold rubbers came up real good. Not much more flexible but they look brand new and re-fitting the rack was significantly easier.

So I fired it up and no more run away idle/throttle! Drove it around the block and it looks like I have a viable bike Must have been a vacuum leak.

 

Quick question - when I get her warmed up, I'm getting a little smoke from the exhaust headers. It appears to be coming from right down the bottom, almost inside the pipes but I can't see any visible oil leaks at all. Nothing on the floor of the garage either. Any ideas?

 

A bit of dribble from last oil change?

 

Mine did same when I first got it running after years of sitting. Condensation / old oil burning off

 

^^ that.

 

Thanks guys. "Ride it some more" is the answer I was after

 

It's pretty rare that I have parts left over but these two bolts and concave washers have me stumped. Any idea where they're from?

 

They look like the 2 bottom bolts holding the oil cooler in place.

 

Because that's what they are. Good eye!.

 

Waddayaknow! Well spotted Simmy!

 

Finally found a local supplier for shims and got all valves within spec and she runs really nicely. Next up I'll vacuum sync the carbs but to be honest, it's pretty nice at the moment. Only real problems are a bit of a hung idle (comes down but slower than expected) and I think a leaky exhaust but I'll go over all that when I have some more time. My only other MC experience is with a V twin and EFI so it's a bit hard to know what to expect. Is the throttle and rev to idle normally quite snappy or a bit slow?

 

I think if you did a running vacuum synch you will find your idle drop will become quick and smooth.

Add a Colortune and final synch and she will be purrrfect.

 

Congrats on a job well done!

 

Thanks guys! A couple of more tuning jobs and I get to do the fun part - ride!

...after I get it across the pits and licensed.