Carb cleaning help please.

[alfa.rbt]

My cyrvy sv developed a very bad misfire so
- Ive checked spark plugs (1000m old iridium) and the sparking sweet against cylinder so guess leads are fine as well.
- might be a water in fuel tank and I'm yet to check that

Ive been told that it's going to be a dirty carbs so I want to take them off and clean them. Only problem is I never done that before and am afraid I might bugger something up soooo would anyone local be so kind to come around and supervise/advice me on sunday while I'm on it? I've got plenty of coffee and biscuts if needed. also i'll buy a case of favorite (enter your favorite lager, cider etc). I could give it to the garage but simply cant afford it and need a bike to go to work monday. I hope I'm not asking for much and will be very greatfull for help!!!

[Jayneflakes]

Have you checked for rain contamination of the front plug lead first?

Then check for the condition of your spark plugs, how do the ends look (http://www.aa1car.com/library/reading_spark_plugs.jpg), is one getting wet with fuel and earthing with out spark?

There are a couple of options to check before you dive in and take things to bits. Good luck.

[alfa.rbt]

cheers for advice, will crack on tomorrow morning with it. hopefully I'll find out whats wrong with my baby :)

[Penry]

I would but your a mission from me, try this http://www.youtube.com/watch?v=HeMjppADyTM but refer to the haynes for removal :)

[DJ123]

when did it start mis firing?

[alfa.rbt]

when did it start mis firing?

Few days ago after I fitted new battery as the old one died.
I didn't ride it in the wet recently, use same fuel station all time ( shell vpower if that matters)

[alfa.rbt]

I would but your a mission from me, try this http://www.youtube.com/watch?v=HeMjppADyTM but refer to the haynes for removal :)

Cheers mate

[DJ123]

did you check the spark plug gaps? is the air filter clean?

[alfa.rbt]

did you check the spark plug gaps? is the air filter clean?

Would the gap change it self?
Air filter looks clean.
Misfire is actually happening at about 6k revs when engineis worm and about 2.5k when cold. Also when it's cold and start misfiring at 2.5k it dies. When at idle it runs fine. Also when on full choke it's at over 3k revs it does not misfire even wyen cold, only when I touch the throttle. Don't know what else to say

[DJ123]

Is the air box sat down correctly, seated & sealed well, no air leaks getting into the system?

[Thunderace]

Airbox shouldn't make any difference to firing you could take it of totally and the bike would be fine until it snuffled up a leaf or some such!

Could be many things fuel injectors, faulty plugs, work top down to find the fault, don't dive straight in and start taking things apart, check the simple stuff first, I read that you checked the spark that doesn't mean they spark well right through the rev range, buy a new set try them, worst case you've got some spare!

Yes the gaps on the plugs can change, and it can cause a missfire.

[alfa.rbt]

I don't think there is but I will recheck it

[alfa.rbt]

Well, decided to take the carbs off and done it. A fair bit of fuel came out of them and i've got it in the clear container. Gues what whater mixed with fuel :(
Next step clean the carbs inside so where do i start...

[speedyandypandy]

The only thing that changed before it started missfiring was changing the battery.....what happened that you knew it was old? did it go bang and than flat? was it not cranking to start.

[embee]

Biggest issue might be that the drain tube which runs from the tank filler recess down through the tank and out the rear has rusted through, it's not uncommon. This lets water directly into the tank from rain/washing.

It's been discussed before but I'm not sure if anyone has managed to successfully "sleeve" this tube, others will advise, or search.

[yorkie_chris]

As you've found water in the fuel usually gives this symptom of fine at tickover but doesn't like to rev. Reason being the idle jets are a bit above the mains so have better chance to be in clean fuel.

Take float bowls off, blow through any holes you can see with compressed air, that will do most of the gain for least complexity.

Just dropping the water out of them has a pretty good chance of curing it for now.

Airbox shouldn't make any difference to firing you could take it of totally and the bike would be fine until it snuffled up a leaf or some such!


Well except it would be completely unrideable and run like a very lean bag of crap...

[yorkie_chris]

Biggest issue might be that the drain tube which runs from the tank filler recess down through the tank and out the rear has rusted through, it's not uncommon. This lets water directly into the tank from rain/washing.

It's been discussed before but I'm not sure if anyone has managed to successfully "sleeve" this tube, others will advise, or search.

That drain hole is a right tw*t.

Zoran TIG brazes them back together which seems the best way. I also heard of someone using the head of a rivet to hold it.

[alfa.rbt]

I've managed to clean the carbs, not much of a dirt inside them but there was some. Also drained the tank and found some more water but not to much. After all that I'm happy to report that bike is happy again and revs like crazy. thanks for any advice thats been given