throttle not passing 2000 without my bike dying

hey everyone...having a problem...

when I first turn on my bike...my idle is bouncing around 1500..but when I try to throttle pass 2000...my bike dies...I tried the basic check ups such as gas, playing with the choke, checked the spark plugs...but still no resolution.....but when I do spray some carb cleaner onto my carb holders, the idle stick does jump up a little bit...is this a leak in my carb holders? any other suggestions on what I can check on?

 

Definitely sounds like a vacuum leak. You should start there sealing up those cracks. Search the forum for ideas but I think a lot of guys use RTV Black Silicone.

Based on what you've written - it sounds like a fuel/air mixture issue but I wouldn't rule out electrical gremlins.

What did the spark plugs look like? Black and sooty?

 

The plugs arent sooty actually they are tan like they are supposed to be. Looks like the only cracked ones are the 2 outside ones (#1 & #4). I was trying to get them off the bike but the inside screws are hard to get to as my allen wrenches are too long at the bend, do i have to take the whole carb system out to get to these carb holders? is there a trick to getting them out?

any help would be appreciated. thanx

 

this happened to me on my 82 xj750 maxim. found vacuum leak in carb holders. they are flexible enough to get off without removing the carbs, just pry them out after loosening the screws. i haven't fixed it yet but i plan to use the black rtv sealant.

 

another thing... i know it sounds dumb, but is the bike warmed up when this is happening? if the bike is still cold then it would make sense that it would die like that.

 

Gonna try using RTV silicone on my carb holders

I'm gonna try using the RTV silicone this weekend...anyone with any tips on using it? should I take off the carb holders or can I leave them on cuz Im having problems trying to get leverage taking out the inner screws on the outer carbs...

 

Intake Manifold Cap Screws are SOFT Steel; pretend to turn until they break.

Intake Manifold Cap Screws are SOFT Steel; pretend to turn until they break.

Intake Manifold Cap Screws are SOFT Steel; pretend to turn until they break.

Intake Manifold Cap Screws are SOFT Steel; pretend to turn until they break.

 

Leave them on and just smear the RTV around the outiside and into the cracks.

 

my opinion, just opinion, is to take them off, if they break, they needed to be replaced anyway.

 

It is not if the carb boots break it is if the bolts break off in the cylinderhead! That matters and it didn't need to be replaced. I try to be careful with other peoples toys and money.

 

Yes - I would agree with Rick and BlueMaxim - pull off everything in the way so you can get to the boots to seal them up.

 

I'm going to suggest you hit them with PB Blaster and let them soak overnight. I have gotten the intakes cleaned up for you and will post pics shortly. If you get stuck, we can always replace the studs. Not that hard. Using a stubby drill, a drill guide block, and a reverse twist drill bit one can remove studs snapped off flush. If anything sticks out, easy street. I've a set of stud pullers from Snap-On that will yank them with 1/8" showing. It has been suggested that you gently heat the studs before attempting to remove them. I think this is a good idea.