The 83 carbs being the BS34's should have the black plastic floats and be set to 22 mm.
Leo
Leo
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XS650 Battery loses charge overnight, After recharge cannot stay running
- Thread starter DylanXS
- Start date
Ok thanks guys, I measured both floats and one was low around 18mm, I bent the tong up as much as I felt comfortable doing without breaking, raised it up to 21mm+- got it all back together, started the bike and it's back to idling! Not popping from exhaust either. It's staying running while warming up and seems to be ok for the most part, slightly wants to bog down. I'm going to test ride it tomorrow see how it goes.
Fred there were several reasons why I suggested a partial clean
The first being that these carbs are complicated and exacting to reassemble, sync, tune and get running again and the po stated that he was new to motorcycle maintenance
Secondly it would appear that it is only the pilot circuit that is giving the problem not anything else as far as we know.
The pilot jet , main jet, pilot air screw and air passages, the float needle jets and the float heights can all be checked removed cleaned /changed and replaced without dissassembling the carburettors and without upsetting the throttle sync and throttle adjustments !
I would say that judging by the cleanliness of the carbs and bolts that it is not long since they were off and cleaned, synced and set etc
My motto is .....if it ain't screwed don't screw with it
The more you fiddle with the more likelihood you introduce problems that were not there in the first place.
Battery was at 40% ?! Something draining it while it sits? Put a tender on it got it back up enough to start. Bike turned over, little gas came out of one of my carbs near the air filter... Maybe I adjusted the float incorrectly? Would it be best to replace the float?
I know this is going to seem too obvious but if the ignition key is turned past the steering lock position does your rear tail light illuminate?
It does on my 79 and I drained the battery several times before I noticed the tail light on
It does on my 79 and I drained the battery several times before I noticed the tail light on
Your statement about not wanting to bend the float tang too much for fear of breaking it has me wondering if you measured your floats correctly, to the right spot on the float bulb. With these plastic floats, you measure up to the top of the round "bulb", not that higher flat area around the hinge bracket. Here's a float set to about 21mm, slightly rich but still in the spec (22mm±1mm) .....
When set correctly, the tang will only angle down slightly from the rest of the hinge bracket .....
When set correctly, the tang will only angle down slightly from the rest of the hinge bracket .....
Hi Dylan,
yeah, that accursed "park" position just one small hardly noticeable click to the left of the "lock" position.
(It's there because some jurisdictions require that vehicles parked on the street after dark must display a rear light)
It'll get you and run your battery flat if you don't know it's there.
And despite what peanut sez about how complicated the carbs are
(compared to the single Amal on my BSA, yeah. Compared to the 4 Mikunis on my XS11, not so much.)
you gotta learn sometime, eh?
Read the carb guide until you can quote it from memory.
Strip 'em in a big tray so as not to lose the parts.
Work on them one at a time so the other is a reference.
Grind up special screwdrivers to an exact fit on the soft-as-shit brass the jets are made from.
Trashcan every crosspoint screw you come across and replace it with an Allen head screw.
One last little trick.
The float pivot posts are frail and can snap off like a carrot if you ain't careful removing the float pivot pins.
Mr Hammer is NOT your friend here.
Some use a dykes (AKA sidecutter) behind the pin's head to start it moving.
I prefer using a spring loaded automatic centerpunch (good one ~$20 at a proper tool store) on the pin's tail end to pop them loose.
After the pin is out sand it down so it don't jam in there no more. It can't get out anyway once the bowl is back on.
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So I re-charged the battery 100%, I can get the ignition to operate however the bike will not start without a bit of throttle. I have to hold it up to keep it running otherwise it dies. Kind of back to square one. What should I look into next?
So I re-charged the battery 100%, I can get the ignition to operate however the bike will not start without a bit of throttle. I have to hold it up to keep it running otherwise it dies. Kind of back to square one. What should I look into next?
Don't be discouraged, your not back to step one. What you know is this. It's getting spark, air and fuel. I know you cleaned them but it might be time to step it up. Deep clean them, every port, every jet. Try using compressed air. Make sure they are synced, check the slides and diaphragms. It's all in the carb guide.
its starting to sound to me like you need to sync the throttle butterflys and set the idle speed . If your butterfly valves are not open sufficiently when starting from cold then you'll always have to give it a bit of throttle in order to start.
Once started you say that you need to keep the choke on also suggests to me that you may need to adjust the throttle stop adjustment so that the engine is getting sufficient fuel in order to idle.
How are you syncing the carbs ? the easiest way to start with is to blow into each carburetor in turn (against the butterfly valve) like a trumpet . Adjust each butterfly opening until it requires identical blowing pressure for each carb. The butterflys only need to be open a tiny fraction but the air flow past the butterflys (sync) needs to be equal .
Ok thanks guys, I am going to rip them apart once more look at the butterfly valve sync more closely than before, and get some replacement hoses on my vac lines, and double check my floats. See attached picture I took (with a bootleg ruler) I measured up 22mm with my float height, but I could have bent the tang incorrectly??
Anyway after I get this done, to adjust my throttle stop is that my idle speed adjuster? Do I just fiddle with settings until the bike idles out?
Also are my fuel screws on top each carb near the manifold? I want to set this back to recommended 3 turns.
Anyway after I get this done, to adjust my throttle stop is that my idle speed adjuster? Do I just fiddle with settings until the bike idles out?
Also are my fuel screws on top each carb near the manifold? I want to set this back to recommended 3 turns.
Didn't you read my post above? You're measuring to the wrong spot on the float. Yours aren't set at 22, probably closer to 17. That's way off and way rich. The amount your tang is bent is a dead giveaway that you've got the float level way off.
No, you'd want to bend the tang down...to raise the floats.
