View Full Version : Blast has trouble starting and won't stay running unless you throttle it

06-10-2012, 12:47 AM
I have an 02 blast and recently ran out of gas. Put it on reserve to get the mile home. Was running rough on way home. Filled gas tank and ran fine for a day. Today I take it out, and it won't stay running unless I keep the throttle on. It was also backfiring like crazy. Now I don't think it will even start. I tried putting it back on reserve, and it ran at idle, then started to get rough, so I switched petcock back to on position and it died. Then I couldn't get it started again. Bad gas, crap in the tank, or clogged something? I'm really stuck now, supposed to go to Laconia bike week in a couple days!! Please help me!!!!

06-10-2012, 12:50 AM
what does the spark plug look like?

06-10-2012, 01:02 AM
It's a fairly new one, without taking it completely out, it looks new. Can you take it out with the tank in the way, looks really tight in there?

06-10-2012, 01:05 AM
I believe the guy I bought it off of put a new one in recently. I've had bike for a little over the month.

06-10-2012, 01:12 AM
it might be flooding and fouled the plug.

06-10-2012, 01:16 AM
Do you have to take the gas tank off to get the plug out?

06-10-2012, 01:26 AM
no you can pull it with the tank in - just take your time - check the brand and # on the plug - most times when you ask for a plug for the blast they give you the wrong one.

they usually give you 1 that is to hot of a heat range.
try 1 of these plugs.

NGK DPR9EA-9 cool (equivalent to Buell 10R12)

HD 10R12A are the stock number for the Blast

you probably have a bad leaking boot - some times it looks ok but is leaking .

this could help also -

Carefully remove plug over idle mixture screw (drill it out carefully) and reset idle mixture screw to 2 1/2 turns from full in or for best idle speed. If best idle is more than 3 turns out, switch to a 48 pilot jet and re-adjust idle screw for optimum idle.

Shim the needle a little higher (~0.05".

06-10-2012, 01:29 AM
Intake Boot Symptoms (Smallest to Largest) :

*) Flat Power Loss - If you are experiencing loss of power while riding flat, not under load, not going up a hill or a steep grade
*) Small increases in fuel efficiency - Do you normally get 65 to 70 miles per gallon, and now it seems your getting 70 to 75
*) Do you have random power loss followed by backfire, then a regain in power
*) Bike will not start, will turn over, but will not start
*) Will idle but dies when you apply throttle.

*) Make sure it is not a gas tank vacuum issue, try to start your bike with the gas cap off (If no continue)
*) Have you checked your fuel is on, the fuel filter &main line into your carburetor? (If yes continue)
*) Are you getting consistent spark from your plug? (If yes continue)
*) Place your hand over your carburetor while attempting to start the engine. You should feel strong suction on your hand, (If not continue)
*) Replace intake boot

Replacement at a garage will run you just under $170, 2 hours labor + part, the part is about $10.00 retail and very easy to replace. Following the Service Manual instructions for checking fuel filter and removing carburetor will get you all the disassembly and reassembly instructions. Be sure you have the boot seated in the grooves correctly, and that the clamps are in the correct grooves and tighten sufficiently.

NOTE: I noticed the smaller issues for about a month before my boot issue got to the point my bike would not start. It has also been suggested that you regularly change the intake boot at least every 2 years.

blast tips / quick ref. (http://www.buellxb.com/Buell-XB-Forum/Buell-Blast/Blast-tips-mods-info-etc.)

06-10-2012, 01:42 AM
could also be the clutch or kick stand safety switches going bad .

or a loose engine ground orthe tank vent may be stuck closed

06-10-2012, 02:25 AM
When I took air cleaner off and tried to start it, it definitely had good suction. It was sucking my palm in. So does that mean its not a boot issue?

06-10-2012, 02:30 AM
Could it be that there was a piece of trash in the tank and was picked up when reserve was put on and is now lodged in a carb jet? Or clogging the fuel line somewhere?[cool]

06-11-2012, 02:04 AM
No, just replace the boot anyways. They are cheap and generally should be replaced regularly anyways.

Start saving for dans superboot.