XT 600 dies on me....

[kwagga]

Hi guys,

I'm new here. Hope you guys doing gr8! Hppy new year!

I'm a bit frustrated with my bike. I'm trying to fihure out what's going on with it, but it dies when i open it. Can't go above 50mph....

So i can drive slow everywhere, but as soon as i give petrol, it diez...

I did put a new airfilter in, service the bike, but that did not help.

I THINK it's the carb and it might be the needle & seat that is finished...?

I did try to change the pin to different levels on the ''jet needle assembly'', but that did not work. It's rather other way around.... It does not get enough petrol then to go anywhere....

Jets - I bought it and it was fine, but just wondering if there is a standard jet...

Anyway. It would be very helpful if anyone can advise me how to fix this.

O yes. XT 600 Yamaha , 1988 model.

Cheers

Kwagga

[Jens Eskildsen]

Sounds carb related. I would take out the primary jets in both carbs and clean them and everything else.

[Pigford]

Check fuel flow from tank....... Take off the pipe from tap to carb, and see if fuel flows nice & fast.... Check filler cap air vent, incase its blocked, causing a vacuum & slowing fuel flow.

Any other symptoms.... black smoke from exhaust? Try putting choke on at higher speed to see if makes any difference?

[Champ]

Hi Kwagga,

Seems that carby problems are taking their toll at this time of year it is winter in the north so condensation could be a problem, :confused1:

My questions are did this problem just start or did it happen when you did something else before this happened?
Check to ensure that you dont have an air leak on the inlet manifold

Sounds like it is starving for fuel, so what’s stopping the fuel?

• I can see no reason to change anything if this was not a previous problem
• Do you have the same result with the tank switched to reserve?
• If it just started did it start after you fuelled it up?
• Did you drain the fuel and check for water or dirt?
• Do you have a filter in the fuel line? If not you should have….. if you do check the filter
• Should the needle and seat be a problem…. Only if it has some junk under the needle and it is over-fuelling the engine this is usually a problem at idle the needle and seat operate as a small valve and only allow sufficient fuel to enter the float bowl as required by the demand of the engine it usually cuts off the flow as less demand is placed on the fuel. Protect this by having a small filter in the fuel line
• Ensure there is sufficient flow from the fuel tank: - if fitted with a vacuum valve check that the valve is working by removing the fuel line at the carb and placing in a clean bottle or jar so that you can examine the contents. Remove the vacuum hose from the carby and provided that there is no fuel leaking from it suck the hose and see if fuel is released from the valve.
• When you start the bike with the air filters removed can you observe the carby pistons rising which cause the needles to rise and allow fuel air mixture to enter into the engine?
• Check the diaphragms by removing them and holding up to the light checking carefully that there are no holes or cracks in the diaphragms
• Check the vacuum placed on the diaphragms

Purchase an overhaul kit and completely strip the carbs and clean thoroughly looking for any abnormalities.
Hope this helps
In the spirit of good biking
Trust all goes well
Merry Xmas and look forward to an exciting new year

Champ

[kwagga]

Thanks for the replies guys!

Ok:

Jens: I've asked the guys at the bike shop to clean the carb, so they did....

Pigford: I will do that and check it.
Symptoms, yes, if I stopped and gave too much petrol, the bike needs to get going again, but unless I use the choke, it would not go.... Yes, black smoke!

Globi:yes and will check that :-)

Champ: The problem just started suddenly. Did not change anything...
- Does not matter if the tank is switched to reserve.
- Starts normally when i fuel it up.
- Nope, did not drain it.
- No filter on the fuel line...
- I'll put a filter in :-) The guys who previously helped me fixing the bike said he thinks the neadle & seat is finished, i should replace it.
- Have not started the bike without the air filters....
- thanks for the advice!!

Thanks everyone. Will checkit out!

Kwagga

[*Touring Ted*]

I had this exact issue and it turned out to be a blockage in a very HIDDEN fuel filter in the float bowl valve...

Loads of carb cleans miss it if they don't know its there.

It's common to gum and clog up !

[kwagga]

Ok....

What's the best way cleaning it? How did u do it?

Cheers

kwagga

[Champ]

Hi Kwagga,

Google carberator Cleaning

1. Video results for carberator cleaning
Click on Vidio results for carburator cleaning and enjoy

Also Google Motorcycle carburettor maintenance and follow any of the self help videos

http://www.webbikeworld.com/Motorcycle-technical-articles/articles.htm

http://www.webbikeworld.com/t2/carb-adjustment

Just a little test before you strip anything down :-

Start the bike and warm up … allow to idle spray some WD 40 around the inlet manifolds a little at a time and trying one inlet at a time where the maifolds joint the carby and again at the head … see what effect this might have on the bike. Note any changes and if revs increase it is likely that you have a leak around the manifold.

By having the exhaust pipes hot spray some liquid ether on the exhaust pipe near the head. The exhaust pipe should be quite hot and the ether should instantaneously evaporate if it doesn’t and visibly bubbles around this will indicate a cylinder with a problem.

I come from a mechanical background but have little experience on motor bikes so my knowledge is a collective from working on other engines.

• As an apprentice we are taught to start at the source and follow a system through. In this case the source is the fuel tank. Start there and make sure the
• petcock is clear and in good working order, drain the fuel and then remove the petcock,
• No filter:- Put one in, just a small inline filter throw away type
• Fuel pump if fitted ensure it is delivering fuel at the right pressure
• Having completed the test I suggested and having noted any changes then tackle the carbs:- the videos will clue you in as to disassembly and reassembly… ensure that replacement parts are available especially o rings gaskets etc (Full carby kits) as they should be replaced at this stage old O rings will leak when they are disturbed.
• As I said and the videos will back me up the Needle and Seat is usually only a problem when something is stuck under the valve and fuel will leak continuously from the carb.
• Follow the instructions for cleaning checking for abnormalities and where the fuel flows to the carbs for any tiny filters usually on the inlet to the Needle and Seat
• Note any adjustments as per video and you should be able to download a manual for your bike from the net this will have the set up procedure for your individual bike.

Just a little information here that may help: - I have a 1977 GS750 Suzuki and although I do most work my self things like multiple carb settings I leave to the experts.
I had a problem with the bike when I bought it was really running ratty hard to start needed choke and don’t touch the throttle or it would flood took ages to settle down once the engine started . I knew I had a CarbX4 problem and by the liquid tests I new I had a leaking manifold. The bike had been altered quite a bit , air box had been removed and pods fitted jets had been altered.
No self respecting Motor bike designer would design a bike to run like this believe me it was a pig.
When I took the carb’s off and the then the inlet manifolds, the O rings in the inlet manifold disintegrated in my hands. To get the bike back to somewhat near new I sourced an air box and put everything back to standard< I chose to have a well known Motorcycle mechanic Acid bath the carby’s and re-kit them the reason being why would I want to set this up and then in may be two years be on a RWT. These guys do this everyday and are aware of all the little individual tricks.
·When you reassemble the carbs take the time to fill the bowls with petrol an leave them stand for a while and ensure there are no leaks before putting them back on the bike Believe me its all part of the job and you may not want the practice of putting them back on the bike and having to remove them again.
· TUNEING It is likely that to get the best tune set up that you take it to someone who is experienced and NOTE WELL a bike that is running lean can burn valves and that is a problem that you don’t want.

By the way the GS now starts and runs as it was designed by the manufacturer, it is yet to be tuned and the carbs properly balanced. Tell you it is a shining black horse that wants to get up and go. Imagine being in the depths of nowhere and some unlikly charachters approach you wanting your wallet and your Rolex and you have an unreliable tired old machine that wont start and takes an hour to warm up and run properley.... not for me Sam I want to be out of there

IF there is something that I can help with I will be watching the posts
Take care and I wish you all the best
Hope this helps

Kind regards
Champ

[*Touring Ted*]

To clean (or remove as some do) the filter...

Take the carb off
Remove the float bowl
Remove the float valve by pushing the pin out.
Cant remember specifics, but its under the float valve.
Be careful not to bend the height adjustment tang or you will have to reset it

Just clean it in petrol or carb cleaner, blow it clean etc..


It's simple to do if you take you time and remember where everything goes !


If its not clogged or blocked, clean the rest of the carb out.

[Livotlout]

Hi Kwagga,

See item 43 in :-

http://i103.photobucket.com/albums/m...tlout/h-06.gif[/IMG]

This is the valve that Ted refers to. The very small filter is the upper component of item 43 in the exploded detail, which blocks easily and causes fuel starvation.

Alec

[kwagga]

Goodness me, you guys r awesome!

Thanks for the replies!

I have not had time yet to fix it, so this morning in to work I stopped 5 times!! It's a bummer when you r in all the busy traffic and your bike starts puffing, then you know......i've got a few seconds to get somewhere to park!!

Not nice, but i think i'll have to do it this Friday/Saturday....

Thanks again for the advice!!!

kwagga

[kwagga]

ok....

Last night i thought i'll do it. Then i started checking the fuel tap. and it looks good. Petrol flow through well. Have not put a new filter in yet, but will do....

Then i took the carb off opened it and cleaned it like on the video's champ suggested. Everything was clean and i did not get anything that was clogged up....? So i've put everthing together again after alot and alot of frustration. Just rediculous to get that carb back. Such a mission that took me ages.

So i came to work this morning without stopping at least, but had to go very slow because of the snow, but i'll have to open it a bit and see if it performs good.....

Some things i was unsure of:

1. The float was not straight, but was basically lying on the bottom of the carb bowl. Is that suppose to be like that?

2. There's a little screw on the bottom of the carb, I think to tune it. Am i correct? How do i know then when it is correct?

3. Idling - It almost cannot idle... So, if i turn it up, does it make any difference to the performance or just the idling?

will keep you updated

kwagga

[Jens Eskildsen]

The screw poiten out to the left of the bike is to drain the carb.

Theres a CO screw (Airscrew, but it actually controls the petrol instead of air)

The Co screw is hidden in a slot on the carb, towards the front of the engine. Of you screw that screw out, the bike will burn richer (open p the fuel) if you screw it in, it will go leaner.

When its cold, the air is denser, and theres more "air" in the air, so ypu bike will burn leaner. And if you also have a low float setting it will be even leaner.

Perhaps a sparkplug check ? post a picture if you do, my guess is its white.

Try to adjust the CO screw out for half a round, see if it helps. It's a flat screw, and as i said, is well hidden. I'll try to get a pic.

Think this could be it.

*Edit*

Heres a beemer carb, dont mind the sizes and shapes, its only to give you the location in case you dont know:

[bacardi23]

Do yourself a favor and check the cylinder compression of your piston!
how many miles/km does your bike have?




Hey guys.. it's been months..sorry, had no ISP...

Vando

[kwagga]

Thanks Jens!

I did fiddle with the air screw, but what happens now is that is started backfiring alot! Donno if that is because of too little or to much petrol....

Also still stop when i open it up....

[quote=bacardi23;271809]Do yourself a favor and check the cylinder compression of your piston!
how many miles/km does your bike have?

How do i check the compression mate?
I have 33000miles on the clock Vando.