Carb float problem?

Ola

Ola

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Carb float problem? *video*

I`ve had problems with my motor for a while ago.. Another thread in page 2 or 3..

Now it starts right up again, and i dont know why really :D

I was out riding again the other day, and noticed a "pattern" in its behaviour.. When riding bumps, jumps, and especially going uphill on bumps and jumps, it bogs right down to idle after some seconds.. Then i need to let it idle for 3-4sec, until it responses correctly again..

My first thought is that the carb float perhaps may be wrong set, and this being a bigger problem uphill than riding flat/downhill?

Perhaps this was the original problem as well, the last time? But that time it didnt start up again after it bogged down to full stop..

I have two small videoclips of it happening, if you would like to see..

http://www.m535t.com/film/trouble.wmv

Right at the top, when i am going to turn, it bogs down and makes me stop.. then i can go again..

Here you can see it happend again..

http://www.m535t.com/film/trouble2.wmv
 
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from the info you have shared T.O.R.S sounds most likely responsible... The fact that it seems to do it going up hill is puzzling however... Check throttle cable free play as sited in you owners manual after you have bypassed it temporarily for test purposes...
 
Have you tried to take it to the dealer? I assume you have checked your carbs, powervalves etc etc? Do you get any warning light?
 
Any ideas welcome right?

Another thing, probably not it but; have you checked your tunnel, if you have a hole, which allows snow to enter the engine compartment? I had a srx 600 with that problem, and going uphill in deepsnow would never go well because there would be a snowspray to the clutches and the sled would just stop.
 
It`s not snow coming in, and i have checked the valves even though they guaranteed has nothing to do with this..

havent taken out the carbs yet, but i`m going to soon i think.. Just a little worried about getting all the air out of the coolant system again..

The dealer for yamaha are 200km from here, so its not an option.. I`ll solve it for sure, but was hoping someone recognized the problem, so i dont need to invent the wheel all over again.. But i`ll do what it takes..
 
I would start with the TORs. Ethier bypass for testing or get on the flat and pin it WOT, let off real fast all the way. Take your thumb right off, then pint it WOT again.

From the video it sounds as though the problem is common to all cylinders. I highly doubt that all three carb are buggered. The one thing all three have in common is the TORS. If that doesn't cure your problem, I would start looking at other things like crank seal, etc.
 
taylzee said:
I would start with the TORs. Ethier bypass for testing or get on the flat and pin it WOT, let off real fast all the way. Take your thumb right off, then pint it WOT again.

From the video it sounds as though the problem is common to all cylinders. I highly doubt that all three carb are buggered. The one thing all three have in common is the TORS. If that doesn't cure your problem, I would start looking at other things like crank seal, etc.
Click to expand...

Ok.
Running flat straight, actually works great.. But didnt try letting off, and pull hard again.. So you might have a point..

Since i am a tech loving dude, i sure would like to know how the TORs really works?
Easyer to solve problems, knowing what each function really does/works..

I searched the forum, but only came across posts telling people to bypass.. no technical explanation..
 
TORS explanation.

The simple version is that there is a microswitch in the throttle block and where the cable attaches to the carbs. The TORS makes sure that the switches are at similar distances when machine is in use. If the carb switch is open and the throttle one is closed then the system kicks in to prevent the sled from running off due to a sticky cable or something along that thought.
 
It is the Throttle OverRide system. There is a switch on the carbs and a switch on the throttle block. They have to work together for the everything to function properly. To put it simply. They are 2 sets of contacts that have to act together. If one is not following the other then the system activates. It's there to prevent situations such as a Frozen open carb. Even tough the slide on the carb may be open (carb switch closed), the throttle block switch would be open. Since the contacts are not in sequence with each other, the system retards from letting the sled take off.

Wehn you are riding WOT and let off the throttle, the swtiches should change state and when you get back on the gas, the system should respond normally (no bog ), but if the contacts aren't following each other properly, TORs will activate and retard the sled.

If you think this is the problem. You can bypass the system to test it. There are 2 bullet type connectors at the carbs that connect the carb switch to the throttle block switch. You can bypass by unpluging them and plugging them into themselves if that makes sense. If you need pics I could probably get some to show the connectors and what they look like bypassed and not bypassed.

Let me know How you make out.
 
Thanks guys.. Bypass is easy, so i will try this out if it doesnt help loosening the cable.. I`ll measure the throttle switch also, to be sure its working ok..

After reading your posts, and this http://www.totallyamaha.net/forums/showpost.php?p=3752&postcount=7 post, i find it possible to be my problem..
It doesnt explain why the motor stopped the last time i was riding, but its a beginning..
 
just another version of the above explanations...

TORS consists of two switches and the Sled's CDI... One switch on the handlebars within the throttle block and one switch at the carb rack.. The switches work such that the CDI must always see a ground potential on the Black/Yellow wire..(most Yamahas)... Either the throttle switch or the carb rack switch must supply a ground potential to this wire.... This is normal operation... If for some reason this ground potential is not evident to the CDI, TORS operation is implemented... The engine will not rev above 3000 RPM and CDI will not reset untill RPM's fall to near idle...

Normal operation..

1) at idle with no hand on throttle block the contacts at the carb rack switch are closed and those on throttle block are open.. This is ok since one set of contacts is feeding ground potential to the Black/Yellow wire to CDI... (NORMAL OPERATION)

2) at trail speed, the contacts at the carb rack are now open but the contacts from the throttle block switch are closed (from grabbing the throttle)... This is ok because again one switch is feeding ground potential to the CDI... (NORMAL OPERATION)

Trouble..

3) at trail speed you decide to let off the throttle... the carbs have frozen open for some reason... the switch at the carb rack has stayed open because ice/ obstruction etc hasn't allowed the carbs to return to idle..(therefor switch is open)... NO ground potential to the CDI... At the same time, when you released the throttle block the switch contacts there open... again no groud potential to the CDI now from either switch.... CDI now limits RPM to 3000 (below engagemnet, and doesn't reset until idle rpm is again seen)..

4) your sled has sit out in the yard for a week and no one but your four year old has been on it... he was pretending to be dad and making Viper noises with his mouth (just like dad when no one is listening).... He's grabbing the throttle hard from corner to corner and probably outdriving dad at this point... He gets off the machine to go and play elsewhere but the carbs or cable had frozen so that the carbs are open to an equivalent 95 MPH......now.... the switch at the throttle block is open because the block has returned to normal... no ground potential to CDI... Similarly because the carbs are frozen open, the switch on the carb rack is frozen open...again, no ground potential to the CDI... TORS will operate and keep the sled from starting quickly next time you pull it over, reving to 8400 RPM and shooting right across the road, before, it drives into the side of your neighbors Buick Century...


TORS when adjusted and working properly is a brilliant saftey device, but when out of adjustment is the source of much grief and headache... If the throttle cable is not adjusted properly, (too tight), then contacts at the carb rack at times dont't close properly... When this happens on the trail at trail speeds, letting off the throttle for the up coming corner has both switches open.. ie. carb rack switch is held open incorrectly by a tight cable and the trottle block switch was opened when you released the block for the upcoming corner... NO ground potential to the CDI therefore limiting RPM to 3000 RPM and resetting only when idle RPM has again been achieved... BUT, because the cable is still too tight, problem will again result...

The switches are nothing mysterious and only simple contacts connected in parallel across the Black/yellow wire of the CDI and chassis ground.... The contacts at the carb rack and those at the throttle block are both a micro switch and are often best replaced if found to malfunction..

Yes a long post.. sorry.
 
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TJ500 said:
just another version of the above explanations...

TORS consists of two switches and the Sled's CDI... One switch on the handlebars within the throttle block and one switch at the carb rack.. The switches work such that the CDI must always see a ground potential on the Black/Yellow wire..(most Yamahas)... Either the throttle switch or the carb rack switch must supply a ground potential to this wire.... This is normal operation... If for some reason this ground potential is not evident to the CDI, TORS operation is implemented... The engine will not rev above 3000 RPM and CDI will not reset untill RPM's fall to near idle...

Normal operation..

1) at idle with no hand on throttle block the contacts at the carb rack switch are closed and those on throttle block are open.. This is ok since one set of contacts is feeding ground potential to the Black/Yellow wire to CDI... (NORMAL OPERATION)

2) at trail speed, the contacts at the carb rack are now open but the contacts from the throttle block switch are closed (from grabbing the throttle)... This is ok because again one switch is feeding ground potential to the CDI... (NORMAL OPERATION)

Trouble..

3) at trail speed you decide to let off the throttle... the carbs have frozen open for some reason... the switch at the carb rack has stayed open because ice/ obstruction etc hasn't allowed the carbs to return to idle..(therefor switch is open)... NO ground potential to the CDI... At the same time, when you released the throttle block the switch contacts there open... again no groud potential to the CDI now from either switch.... CDI now limits RPM to 3000 (below engagemnet, and doesn't reset until idle rpm is again seen)..

4) your sled has sit out in the yard for a week and no one but your four year old has been on it... he was pretending to be dad and making Viper noises with his mouth (just like dad when no one is listening).... He's grabbing the throttle hard from corner to corner and probably outdriving dad at this point... He gets off the machine to go and play elsewhere but the carbs or cable had frozen so that the carbs are open to an equivalent 95 MPH......now.... the switch at the throttle block is open because the block has returned to normal... no ground potential to CDI... Similarly because the carbs are frozen open, the switch on the carb rack is frozen open...again, no ground potential to the CDI... TORS will operate and keep the sled from starting quickly next time you pull it over, reving to 8400 RPM and shooting right across the road, before, it drives into the side of your neighbors Buick Century...


TORS when adjusted and working properly is a brilliant saftey device, but when out of adjustment is the source of much grief and headache... If the throttle cable is not adjusted properly, (too tight), then contacts at the carb rack at times dont't close properly... When this happens on the trail at trail speeds, letting off the throttle for the up coming corner has both switches open.. ie. carb rack switch is held open incorrectly by a tight cable and the trottle block switch was opened when you released the block for the upcoming corner... NO ground potential to the CDI therefore limiting RPM to 3000 RPM and resetting only when idle RPM has again been achieved... BUT, because the cable is still too tight, problem will again result...

The switches are nothing mysterious and only simple contacts connected in parallel across the Black/yellow wire of the CDI and chassis ground.... The contacts at the carb rack are open to environment and can be cleaned periodically... Those at the throttle block are a micro switch and are often better replaced...

Yes a long post.. sorry.
Click to expand...

Great post! Thanks!

I`m just back from the garage, and i think perhaps the cable was a little tight as you guys thought.. i adjusted it, so it JUST makes full throttle when fully squeesed, and it made some more play at idle! Hard to explain how much, but definently better..

Hoping this solves the problem, and if not, then i now know how to test my way through the TORS system!

Ola
 
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