Ninja EX500 carbs on an XS650?

[troopthrowback]

Just cleaned the passages again with carb cleaner and compressed air, check seats are clean. I'll pull again, try the toothpaste polish, install old needle valves and see how it goes. The toothpaste is news to me, but sounds like a good idea.

 

[troopthrowback]

Oh yeah, a internal tank filter plus external in line. No gunk. Pulling my hair out!

 

[troopthrowback]

Ok, pretty much at a loss. Toothpaste polished the seats, new float needles, float height set. Leaks profusely. Toothpaste polish the old float needles, install those: leaks profusely. All ports cleaned with carb cleaner and compressed air at 110#. What next?

I did notice slight dimensional differences between the old and new float needles. Namely the new ones have about twice the spring length. This changes the appearance of the float height setting until it's checked with the carbs upright.

I'm totally at a loss on where to go from here.

 

[xs650dreamer]

I'm pretty sure you checked your float height right ?
Put you hose on the fuel inlet and blow into it while pushing the needle into its seat air should not enter

 

[Maurice]

Use the clear tube method for checking float height?

 

[troopthrowback]

What's the spec on it? I couldn't find that. I just made sure they were even. Great, now I've done it!

 

[Maurice]

clear tube: within 1 to 2mm below the bowl level IIRC.

 

[troopthrowback]

Ok, the valves are seating by blow test. Its gotta be height!

 

[troopthrowback]

Off to find some clear tubing...

 

[xs650dreamer]

Yea man it's your height. Your lucky those carbs have that screw at the bottom like the bs34s best way to check level in my opinion. Oh once you get the tubing set your carbs up so they're level with a remote fuel source. You know how to do the clear hose check ?

 

[troopthrowback]

I remember reading it here earlier on. The process is simple and makes sense, but what is the recommended method for adjusting float height?

 

[xs650dreamer]

Bend the tang since yours are leaking I would bend it down. Remember the carbs are up side down when messing with float height so a higher float level will give you less fuel and a lower one will give you more fuel. You get what I mean ? If I were you I'd bend the tang just a little so they don't pour all over you when you're checking fuel level and who knows you might get lucky on get it dead on

 

[xs650dreamer]

That's why the clear fuel method is nice once you messed when the tang a little and closed them back up you c an see exactly where your fuel is even if your floats are a little crooked or something

 

[troopthrowback]

I'm very close now with the tab bending method, very quickly running out of room for adjustment with these replacement needle valves!

 

[troopthrowback]

Very frustrated. Got them set don't hey don't leak, installed. Very hard starting, choke full on. Mixture screws at 1.5 turns from closed.idles only, does if I give throttle. Adjust out to 1.75 turns, no better. Adjust to 1.25 turns, no better. Intermittent "Pop" at idle. Pull choke off after 2 minutes of mixture adjust, motor does. Left carb leaking.

I adjusted the floats so they only visibly move, I'm talking no measurable amount of movement. Blow test so that if I touch the float it stops. Flow is restricted when in open position, that's how little movement is allowed.

How am I the only one with this issue? What am I screwing up?

 

[troopthrowback]

I think I'm done. Pretty frustrated with not being able to keep these from leaking. I've torn them down about 29 times now, adjusted the floats until they move only microscopically, tired twos offering pairs if float needles including a brand new pair, polished the seats several times (they are shiny and uniform) and have not been able to prevent leaks. Been at it for four hours now with no solution.

 

[troopthrowback]

I've rechecked the floats, no holes in them (I had a leaky float in my bs38 pair). I'm at a loss...

It'll fire despite leaking floats and run for approximately 8-10 seconds then it dies. Seems much like fuel starvation after flooding the carbs. No choke needed, cold motor.

Motor was a reliable runner with the bs38 pair on it just prior to swapping. Stock bore 650 with less than 10k on the clock.

 

[XSLeo]

I haven't taken my carbs that far apart, so I don't have anything to say about how my float valves are, but if you take pics of the old parts and new parts maybe we can figure it out.
Leo

 

[troopthrowback]

I'll do that tomorrow. Honestly after 6 hours of battling with them I was ready to throw them over the fence. I'm hoping my head will cool enouhg for me to look at them again tomorrow.

 

[pekka]

Intermittent "Pop" at idle.

I also had this issue. Pop out of carbs. It got better after setting ignition timing correctly. I had the timing too retarded at idle (almost at TDC). I set it to the proper advance and it idles much better now.

Also had leaking float valves after putting in new float needles. Had to put the old needles back to stop the leak... Quality of aftermarket parts I think that there should be no need to bend the floats from stock setting. My fuel levels is a bit higher than the gasket surface when measured with the clear tube method.

Pekka