Neeed help with 2001 sherco 2.9 please.

[basilbug]

My bike will not start with the choke on at all. It will rev up a little then die, like it's not getting enough gas. It will do this as long as the choke is on, but never start.

When I do eventually get the bike started, which is very hard to do, I will put the choke on and the bike stalls. It will not run at all with the choke on.

Now, with the bike warm, it will start all day long on the first kick.

Any suggestions of what I should clean first?

Thanks

Edited November 13, 2011 by basilbug

[laser17]

When you use the choke, do you keep the throttle closed or do you open it?

What carb and size choke jet are you using? Have you checked the plug after trying to start it with the choke? Is it wet?

[Bender-250xl]

+1 on checking the spark plug. see if it is wet/oily AND check it is sparking.

have you done any work to it recently? have you ridden it recently (before this started happening)?

is the fuel still good? has it been sitting for a while?

[2PLY]

A long shot, but have you opened the flywheel cover to look for water? A large amount of water in there could be getting spun up to short things out until it gets hot enough.

I had a similar thing happen on my Gas Gas but it didn't get bad enough to prevent it from running.. It just didn't run right until I found the water.. Again, just a long shot.

[basilbug]

When you use the choke, do you keep the throttle closed or do you open it?

What carb and size choke jet are you using? Have you checked the plug after trying to start it with the choke? Is it wet?

Yes, I always keep the throttle closed when starting a cold bike with the choke on. The bike is stock.

[basilbug]

+1 on checking the spark plug. see if it is wet/oily AND check it is sparking.

have you done any work to it recently? have you ridden it recently (before this started happening)?

is the fuel still good? has it been sitting for a while?

The bike was sitting for a while. But it idles very well. I can tell its not getting enough gas with the choke on. Anyone ever work on the carb? Somehow the choke bypass passages might be clogged?

[basilbug]

A long shot, but have you opened the flywheel cover to look for water? A large amount of water in there could be getting spun up to short things out until it gets hot enough.

I had a similar thing happen on my Gas Gas but it didn't get bad enough to prevent it from running.. It just didn't run right until I found the water.. Again, just a long shot.

That's to much of a long shot. But I checked and it's dry. I kick it and it sputters a couple of times before I turn the choke off and then it will start with the choke off. But it's very hard. Go to baby it till she warms up.

[basilbug]

Remember that the bike runs great. Just will not start with the choke on. It's getting spark. If it runs, the gas does not matter. No need to look at a spark plug with the bike running great. It starts with the choke off, but difficult. And with the weather getting colder, it will be very hard if not impossible to start then.

[MX Tuner]

I'm going to go out on a limb here. Clean the carb.

[2PLY]

I'm going to go out on a limb here. Clean the carb.

A BIG +1... I thought you had already taken the carb apart. Any time a bike sits for a while and then has problems like that it's an automatic carb cleaning time..

If you can, catch any gas that drains from the carb in a cup or glass to look for water and dirt and take the choke valve apart and look for a bad O-Ring and use a silicone grease like Sil-Glyde to lightly lube it. You can get that stuff at NAPA auto parts, they have re-branded it with their name.

Blow out all of the holes and jets with compressed air in both directions if possible.

[laser17]

Remember that the bike runs great. Just will not start with the choke on. It's getting spark. If it runs, the gas does not matter. No need to look at a spark plug with the bike running great. It starts with the choke off, but difficult. And with the weather getting colder, it will be very hard if not impossible to start then.

wrong -the plug can tell you alot. If you pull the plug after trying to start it for a couple of minutes and it soaking wet, the bike could be flooding on you. If its bone dry, you could have a clogged jet. Would be helpful to know those types of things before guessing on other issues. Its also a very simple thing to check before you start taking other steps. I also agree that opening up the carb and having a look is a worthwhile action to take at this point. Also - you say the bike is stock - did u buy it new? Have u had the carb off recently? Did the bike just recently start doing this all of a sudden? (the all of a sudden part points to a clogged jet or carb port)

[2PLY]

Almost sounds like it's flooding with the choke on. If this is a Delorto, the rubber seal at the bottom of the choke valve may be damaged and allowing too much gas to flow.

On thing you should try to see if it is flooded is to turn the throttle wide open and hold it wide open for at least 5 strong kicks to see if it starts then. Start with the choke on cold and after it sputters and then stops, open the throttle full with the choke off and see if it fires up in about 3 to 5 kicks.. if so, it's flooding.

A wide open throttle prevents the idle circuit from adding any gas since it needs a vacuum at the slide to pull gas from the idle circuit and with the throttle wide open at kicking speed, there is not enough air velocity to pull any gas from the main jet so you can quickly clear the engine of excess gas that way. Doesn't work with fuel injection systems as far as I know,

Regardless, if you have not serviced the carb in the last year, it's time to freshen it up and look for water, dirt and rotten rubber parts.

Oh yes, and it's not a bad idea to drain and rinse your gas tank out and remove the petcock and inspect it for dirt.

[2PLY]

BTW, I was going to post a photo of that Sil-Glyde yesterday but didn't know where I put the photo... Found it!! So get yourself some of this stuff.. It's the same stuff that Jim Snell shows in his GG repair videos:

(I think Laser17 is responsible for the silly "Best Wishes"

[basilbug]

I'm going to go out on a limb here. Clean the carb.

Lol! Was planning on it:thumbsup:

[basilbug]

A BIG +1... I thought you had already taken the carb apart. Any time a bike sits for a while and then has problems like that it's an automatic carb cleaning time..

If you can, catch any gas that drains from the carb in a cup or glass to look for water and dirt and take the choke valve apart and look for a bad O-Ring and use a silicone grease like Sil-Glyde to lightly lube it. You can get that stuff at NAPA auto parts, they have re-branded it with their name.

Blow out all of the holes and jets with compressed air in both directions if possible.

The bike runs great though. All the bikes I have when sitting for awhile, the idle jet gets clogged up, never the choke. But the bad o- ring is a great idea, thanks:thumbsup:

And thanks for the pic too

[basilbug]

Almost sounds like it's flooding with the choke on. If this is a Delorto, the rubber seal at the bottom of the choke valve may be damaged and allowing too much gas to flow.

On thing you should try to see if it is flooded is to turn the throttle wide open and hold it wide open for at least 5 strong kicks to see if it starts then. Start with the choke on cold and after it sputters and then stops, open the throttle full with the choke off and see if it fires up in about 3 to 5 kicks.. if so, it's flooding.

A wide open throttle prevents the idle circuit from adding any gas since it needs a vacuum at the slide to pull gas from the idle circuit and with the throttle wide open at kicking speed, there is not enough air velocity to pull any gas from the main jet so you can quickly clear the engine of excess gas that way. Doesn't work with fuel injection systems as far as I know,

Regardless, if you have not serviced the carb in the last year, it's time to freshen it up and look for water, dirt and rotten rubber parts.

Oh yes, and it's not a bad idea to drain and rinse your gas tank out and remove the petcock and inspect it for dirt.

Very good suggestions too. Thanks:thumbsup: