XJ750 dying

Last fall I cleaned the carbs, synced, float levels, new oil... Bike is running great, except when stopping abruptly, then it dies, very consistently.

Was coming up on a light and it changed to red rather quickly, stopped moderately quickly, bike died while I was still rolling, never had that happen before.

So when I got back to the garage I was testing it out, and was just rolling the bike in neutral and if I hit the brakes quickly, the bike dies, every time....

Any suggestions or just clean the carbs again after sitting all winter?

 

Sidestand switch flaky?

 

High float levels would be my guess.

 

Sidestand switch is disconnected.

I will recheck float levels, just curious though, how would float levels cause this issue?

 

If the floats are set too low then the fuel level may just barely be high enough for it to be picked up under normal riding conditions. Braking will cause the fuel to slosh forward, making the fuel level too low to be picked up.

 

Hmm.. They would really have to be off for that to happen, they were set last fall, I'll open up the carbs to tomorrow to check though.

Thanks for the feedback.

 

You don't need to open the carbs to check the fuel level. Use a length of clear tubing attached to the float bowl drain. Use it like a spirit level.

 

What Moe said Beat me to it lol

 

Yea

Fuel level was actually just a tad high, adjusted the floats and they are all in spec now. Shot some cleaner in them while I had em off. I still have the issue with it shutting off when the engine is cold, but doesn't do it when it's hot.

I think I have a slide sticking now though... When I'm just sitting there and give it a little gas, the RPMs arn't coming down fast after I let off.

Something funky in there, I'm just gonna give them a thorough cleaning, and I'm gonna make sure to drain them this fall instead of leaving the gas in them. :?

 

Just a little update in case anybody cares.

I rechecked the vale clearances just to make sure, all were good except for one exhaust valve which was quite tight. Which seems kind of odd that just one would be out... Went from a 265 to a 255 and fixed that issue.

Then after giving the carbs another thorough cleaning, polishing up the slides to perfection and actually backing the pilot screws out another ~1.25 turns everything seems to be running even better than before.

 

Glad it's working out better for you!

 

Hanging idle means you're out of sync; not that a slide is necessarily hanging up.

 

The hanging idle seems to be all better, but good point, probably wouldn't hurt to sync again especially now that I've changed that one shim.