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[Nekowrites]

I am hoping someone can give me some advice for my next step.

My blast died on me at a stop sign. I walked it home get it apart and found that the sparkplug had come apart. The small screwed on top piece was stuck in the cable. I replaced the plug but no joy. Next I replaced the battery, which needed to be replaced anyways. When that didn't work I cleaned the carbs with gum out. After doing that I am now to the point in the video below...

Please Obi-Forum Kanobi you are my only hope.

https://youtu.be/htxeWCmwW9k

 

[Cooter]

Lone Starr will have to do

Will it re-start right away? Or only after you wait awhile?

Run it again... and after it dies... back out the screw on the bottom of the float bowl 5 turns, does a shot glass worth of gas come out of it? Is it empty?

I suspect it's empty. Check that the tank has enough fresh gas in it, make sure the petcock is not clogged and the fuel line isn't pinched or clogged.

If that all checks out then take the carb off the bike and have it taken apart and ultrasonically cleaned by the oldest mechanic you can find. Even a small engine repair shop should be able to do that for you.

Or buy a NEW carb off e-bay.

 

[Nekowrites]

No it won't start right back up. I will give this a try after dinner. Thanks!

 

[Nekowrites]

I learned a valuable lesson tonight... When taking the float bowl off... Remember to turn the pet cock off.

Long story short there was fuel in the bowl.

 

[Cooter]

Don't take the bowl off. Don't shut off the petcock.

To continue to diagnose why its dying and not re-starting right away, you need to know if there fuel in the bowl right after it dies

To do that,

Run it again... and right after it dies... back out the screw on the bottom of the float bowl 5 turns, does a shot glass worth of gas come out of it?

This one:



I know thats not a Blast carb.

 

[jetlee]

Don't take the bowl off. Don't shut off the petcock.

To continue to diagnose why its dying and not re-starting right away, you need to know if there fuel in the bowl right after it dies

To do that,


This one:
View attachment 16112


I know thats not a Blast carb.

Stock Blast carb does not have a drain screw.

 

[34nineteen]

I always learn something new about the Blast whenever Jetlee comes around.

 

[Nekowrites]

I THOUGHT I WAS CRAZY!!!!!

OK because that is why I took the bowl off because I didn't see a screw. So I guess then my question is does anyone know what I should do next?

 

[34nineteen]

I THOUGHT I WAS CRAZY!!!!!

OK because that is why I took the bowl off because I didn't see a screw. So I guess then my question is does anyone know what I should do next?

The Blast has some weird things on it that we assume are on all carbs, such as accelerator pumps and float bowl drains.

Get some starting fluid and run the bike with the air filter off until it dies. Then immediately after it dies spray some starting fluid into the carb. If it starts back up, you have a fuel starvation issue. If not, its likely ignition related.

Have you checked to make sure the fuel tank is venting? When it dies remove the fuel cap to see if you can hear air rushing into the tank.

Have you checked the fuel lines to make sure they are not blocked?

If someone added a fuel filter, is it clogged?

Is the petcock flowing fuel or is it clogged? Is it turned all the way to one position or another?

It could very well be that fuel flow is being restricted just enough so the float bowl runs empty while the bike is running, but still trickles out enough fuel to fill the bowl over time.

Have you checked the float height? Although if you werent having problems from the start, its likely not an issue now.

Or it could be that the float is leaking gas into it and holding the needle and seat open too long (float height too low) and it just runs too rich until the plug fouls. Usually thats indicated by black smoke coming from the exhaust pipe.

Either way, the video does sound like it is a fuel starvation issue since it gradually runs slower and slower until it cant. If it was ignition, it would just stop.




Before you roll your eyes at the video, there have been a lot of people on this forum who have done that or equally dumb things like hooking up their battery backward.

Or putting DOT 4 brake fluid in their brake reservoir when it clearly says DOT 5.

The fuel system on a Blast is very similar to a lawnmower.

 

[Cooter]

Stock Blast carb does not have a drain screw.

Thanks.


Still trying to help him diagnose the Blast the same exact way 34:19 is.

 

[Nekowrites]

Cooter, 3419, jetlee - thank you all for chiming in. I really appreciate it.

So the petcock is good. And I went ahead and replaced the fuel line. I believe I am getting get good flow out of the gas tank I didn't hear any sucking and I fired it up with the gas cap off. I am still having the issue.

Is replacing the carb my next step? And does it have to be a stock Buell Carb or can I buy an aftermarket one?

 

[Barrett]

You mentioned "carbs". You attempted to disassemble part of it with the fuel valve ON. You "believe" you're getting sufficient fuel flow from tank to carb.
You clearly have no idea what you're doing nor sufficient skills to resolve this. Seek assistance from someone who actually does.
From the vid: NOT ignition problem. Fueling problem.

 

[Nekowrites]

You mentioned "carbs". You attempted to disassemble part of it with the fuel valve ON. You "believe" you're getting sufficient fuel flow from tank to carb.
You clearly have no idea what you're doing nor sufficient skills to resolve this. Seek assistance from someone who actually does.
From the vid: NOT ignition problem. Fueling problem.

This was extremely helpful. I am lucky to have access to someone with your ability to see so clearly. Thank you for letting me bask in your greatness for even a brief moment.

 

[34nineteen]

Why not just pull it off and bring it to a motorcycle shop that works on carbs. Its just a Keihin CV40 carb, so just about any shop that is worth their salt should be able to easily clean and rebuild it.

If you want to buy a new carb you can, but most new carbs are going to be set up for an 883 or 1200 motor, which will mean you will need to send it to someone to set it up for the 500 motor in the Blast anyhow.

Unless the carb is physically damaged, there is no need to buy a new one. The Keihin CV style carb has been used in many different applications and is a very simple unit. But if you insist, there is a brand new, in the box (but probably sitting on a shelf for 12+ years) Blast specific one on eBay now.

 

[Nekowrites]

Why not just pull it off and bring it to a motorcycle shop that works on carbs. Its just a Keihin CV40 carb, so just about any shop that is worth their salt should be able to easily clean and rebuild it.

If you want to buy a new carb you can, but most new carbs are going to be set up for an 883 or 1200 motor, which will mean you will need to send it to someone to set it up for the 500 motor in the Blast anyhow.

Unless the carb is physically damaged, there is no need to buy a new one. The Keihin CV style carb has been used in many different applications and is a very simple unit. But if you insist, there is a brand new, in the box (but probably sitting on a shelf for 12+ years) Blast specific one on eBay now.

That is what I will probably do (Remove it and take it in for a clean/rebuild) we have a shop here in town that I think should be able to do it. Thanks.

 

[Cooter]

I for one, like that idea:eagerness:

take the carb off the bike and have it taken apart and ultrasonically cleaned by the oldest mechanic you can find. Even a small engine repair shop should be able to do that for you.

If your diagnosis is correct and the fuel supply is flowing enough, its basically down to a sticking float or clogged needle/seat.

 

[34nineteen]

the oldest mechanic you can find.

Like you?

 

[Cooter]

Hey! How dare you! I'm not a mechanic!

 

[jetlee]

Thanks.
View attachment 16113

Still trying to help him diagnose the Blast the same exact way 34:19 is.

I haven't said anything else, because it would just be repeating what y'all're sayin', but then I thought about this...

It could be a clogged petcock. It's an easy test, but tastes horrible.

Disconnect the fuel line from the carb (valve off). Let it drain and air out for a minute. Now put your mouth on it and blow, then turn the fuel valve on. Turn the valve off again before you stop blowing or you will suck gas.

If there's crap in the valve, you will blow it out into the fuel. This doesn't solve the problem of crap in your tank, but it will open a clogged valve temporarily. If the bike idles/runs fine after that, that was your problem, now remove the petcock to clean your tank out. If that doesn't solve your issue, I'd lean towards a sticky float; for that, just spray the ever-loving crap out of the hinges and fuel inlet with carb cleaner.

 

[Cooter]

Ya we are all on the same track:eagerness:, seems fairly obvious somethings causing fuel starvation to, or inside, the carb:

make sure the petcock is not clogged

Use a hose thats longer than the top of the tank and you won't drink gas:black_eyed: