Has my bandit been frozen to death? :(

[dragstaar]

Hey all

I have a Bandit 600 (2000)

Well, I went out this morning, started my bike up on the choke, and she fired up first time. Full tank of fuel, fresh from the night before. A lot of the bike was iced over.

So i ride off, choke turned off, and she started to make that spluttering noise that you have when you start to run low on fuel. there wasn't a noticable difference in the acceleration though. And it got me through my whole 20 mile commute. Every now and then, when i cut off the throttle then opened it again, there'd be a small backfire.

I noticed the noise was only there at low revs (2-3k)

On the way home (i kept my bike indoors in the heated office ) she sounded okay.

I don't have a garage, and wanted to know whether this had anything to do with the temperature plummet, i think it was -2 last night where i live. Is it okay to ride the bike that cold?

thanks in advance

[flumpy7]

I've never had a bandit, but the fact that this happened after a particularly cold night makes me think carb icing. Someone who knows more about bandits will be able to tell you if this is an issue for bandits.
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2012 Sinnis apache

[Ingah]

I'm pretty sure carb icing is a common issue on Bandits. Quite what it is though, i'd have to google.
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-- Ingah

[Paddy Blake]

If it happens again open the fuel cap and listen to hear if it sucks in air.
Ice might be blocking the tank breather.
Clear the frost/ice around the fuel cap.

[weasley]

This has carb icing written all over it.

Have a Google for Silkolene Pro-FST. It's a fuel treatment to help prevent icing.

[defblade]

Yep, carb icing.

Seems some do it, some don't..... my 650 oil-cooled does Sounds nice running on 3 (maybe I have a Triumph hankering...?) but things get a bit shit on 2

Check the carb heaters are working first - the wire to mine was disconnected (probably when I was wiring the heated grips ) which didn't help!

Wynns Dry-fuel can help according to t'internet and indeed it did make things much better, but I was using half a bottle per tank which would run expensive.... I've been given a bottle of the pro-fst by a helpful bloke who's got fuel injection now but it's been snowing since so no report!


Also, turning the bike off and letting the heat soak through the carbs for 10 minutes can sort it for a while, but a bit of a sod on the way to work.

Dealer reckoned it was worth cleaning out the carb bowls too as water can sit under the petrol in those and play up too.

Carb icing happens when cold/damp air is being sucked through the carb rapidly, causing temp drops and then ice forming and potentially blocking jets etc. Seems to happen more in UK than most places as we're colder and wetter Still doesn't explain why only some bikes on a particular model suffer but them's the breaks.
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Honda Varadero 125cc => Suzuki Bandit 650 33bhp => 77bhp =>
BMW K1200R Sport 163bhp => Aprilia Shiver GT 750 95bhp

[Paxovasa]

It does sound like carb icing, mine has suffered from it occasionally.

As has been said check the wires are connected to the carb heaters, if it starts again lower your speed and keep the revs up (it works for me).
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Suzuki GSF600 K3 (in the fastest colour, black).

[defblade]

[dragstaar]

thanks for all the replies! Is it bad for the bike to drive out whilst the carbs are iced, I worry about it damaging my bike.

[defblade]

[MarJay]

I actually think you all might be wrong about carb icing.

Carb icing occurs when there is moisture in the air and the venturi effect of the carb cools the incoming air. Carb icing typically occurs at an air temperature of about 5 degrees centigrade. The Carburettor cools the 5 degree air (which is laden with moisture) to below freezing, and the moisture freezes in the venturi, changing its shape.

The shape of the Venturi is critical to the operation of the carb, and so the fuelling changes along with the shape of the venturi.

If the bike is left for a couple of minutes after the engine has been turned off, then the ice will melt from the heat of the engine. The problem will then appear to have gone away until the carb freezes again. The reason why this cannot occur in air colder than 0 degrees celsius is that the moisture in the air has already frozen, and cannot freeze to the sides of the Venturi. This means that in very cold weather bikes that suffer from carb icing are generally not affected.

Your carbs are not frozen when the bike isn't running... So I doubt it is carb icing to be honest, especially if the air temperature is -2.
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British beauty: Triumph Street Triple R; Loony stroker: KR1S; Track fun: GSXR750 L1; Commuter Missile: GSX-S1000F
Remember kids, bikes aren't like lego. You can't easily take a part from one bike and then fit it to another.

[defblade]

[MarJay]

[Walloper]

[Moo.]

My carbs iced up, throttle stuck open :o scary as hell xD
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A2 Passed 18/6/10

[dragstaar]

[dragstaar]

so if its not carb icing, then any ideas on what it could be?

[dragstaar]

Oh yeah, Sorry, i know the Throttle sticking was because it was frozen to fuck.

I thought you were saying that the spluttering was not because of the carbs icing. I am cONFOOos, So im gonna get some pro FST and dump it in the tank. How long will it take to take effect you reckon?

And the Carb heater connections seemed fine, but the Haynes manual's method of testing looks waaaay over my head!

[HD]

[tahrey]

there might be something in the air, mine was doing this in the garage earlier. right bugger to get going, and not happy off choke for quite a while, and sounding sort of different. never heard it backfire before neither, even last winter, but it did today. maybe leftover summer fuel with a bit too much water in it (condensation or just legally allowed) or some other additive that doesn't like cold? it's been standing a while.

water being generated somehow (maybe even ice inside the pipework that's melted) could explain an icing effect. or even air that's not quite frozen, but quite close to it, and so relinquishes its vapour readily as it goes through the fridge-cooler-esque venturi... there's a reason most carburetted machines have carb heaters after all. could even be the fuel freezing if it gets REALLY cold from effective windchill.

I don't know about the specifics of it at all, suspended moisture etc (hey, you get clouds on freezing days, so maybe water vapour acts differently to liquid water? or it might be a lot of molecular-sized bits of airborne ice that only clump together into snow or hail under the right conditions, same as rain forming?) ... just seen a good few claims of this stuff happening on very cold and freezing days over on a car forum I used to frequent.

Simple enough test, really - does it run fine at low speeds, but then splutter or even die if you go faster... thus using higher revs and wider throttle, pushing more air through at higher speed? And slowly but eventually recover if you slow down (more than what you're forced to, that is)? The classic thing was someone trucking along the motorway at 70-80, then being forced down to 50 in the inside lane on full throttle, but being able to get back to a cautious 60ish if they suffered 45 or so far a while.

The other thing might be unhappy ignition leads/coils. I've personally suffered variants of this on injection engined cars which were traced to leads or coils which would have been borderline but operating satisfactorily in dry, warm weather, but couldn't keep up the pace once things got wet or cold (changes the insulator conduction - particularly if it's slightly cracked so rain or condensation can get in... if it's ice, it'll melt and turn to water after a while because of engine heat, they're a lot closer to the block than the carb). One of them didn't run on all cylinders until revved quite hard (regardless of throttle opening), the other just lost power and saw me dragging along at 60mph in 4th on WOT, having been easily cruising 90 in 5th before the rainstorm hit.

[Robby]

Those with a stuck throttle aren't suffering carb icing (generally, unless it's really bad). You're suffering from ice jamming something external. I had this the other day where my throttle was stuck almost closed, but enough to nurse it along. Melted enough to open the throttle after a mile or so, with revving it a bit at a standstill to get some heat soak going.

Bio ethanol will absorb water, but it won't leave water sat at the bottom of your tank - it will leave a water/ethanol mix (dilute ethanol) which should get shaken back into the fuel and pulled through the engine with the motion of the bike. Better to have some ethanol in the fuel pulling water into circulation, than water that gets into your tank being able to separate out of the fuel and sit in the lowest part of the tank, slowly rusting it away.