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Zip Tie Accelerator Pump / Leak Jet Questions

6648 Views 16 Replies 9 Participants Last post by  Joester
Does anyone have any pics they might have snapped of where you zip tie the accelerator pump open?

Also can you get a size 35 leak (or do they call it accelerator?) jet at your average Yamaha dealer?
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the search tool is awesome. And there is a topic in the pinned section of "Tips and Tricks"
QUOTE (joseph who? @ Jun 9 2008, 07:40 PM) index.php?act=findpost&pid=681994
found this over on yfz tech.



Where the rubber o ring is i put a small zip tie instead because there was still play in the little lever when i punched the throttle real qiuck with the rubber ring ( it would streatch). I am running a 45 pilot and 35 leak jet with the ac pump screw turned OUT i think half a turn or alittle more. The bog is totaly gone. The way it runs now is friggin amazing with no bog.[/b]
there ya go
you dont tie it open, it will still move, you just take the play out of the linkage.

you should be able to find a accelerator jet at a dealer, but sadly, most dont know what they are.

if you want, ask them to pull up a parts diagram and show it to them, its on the bottom of the bowl...
How come no one just screws in the screw right there under that spring? You all are using a o-ring or zip tie why not just screw in the screw till there is no wiggle room?
QUOTE (Terse @ Mar 9 2009, 12:54 AM) index.php?act=findpost&pid=755526
How come no one just screws in the screw right there under that spring? You all are using a o-ring or zip tie why not just screw in the screw till there is no wiggle room?[/b]

doesnt that force the two apart, actually shortening the accelerator pump squirt?
I have no idea. I've never messed with it.
yes, screwing in the screw does reduce the full potential that the AC pump has, and zip tieing it does not. at least i think thats what happens when you mess with that screw
I used a small O ring along with a #35 leak jet and a Raven pump cover. It works great and I have no more BOG.
I guess my question is, if the bog is caused by fuel starvation, wouldn't I want go INCREASE the size of my leak jet from the stock 40 to say, a 45 or so ... Why would I want to DECREASE the size of my leak jet down to a 35?

Also, if I don't have any play in my accelerator pump lever, why do I need to zip tie it?
I was wondering the same thing, stock is 40, what would going to a 35 help? Or is a 35 bigger?
QUOTE (king450 @ Apr 11 2009, 08:26 PM) index.php?act=findpost&pid=768826
I was wondering the same thing, stock is 40, what would going to a 35 help? Or is a 35 bigger?[/b]
35 is smaller and the bog is caused by to much fuel going into the bowl or something like that so a smaller size doesnt let as much fuel in and cause a bog.
QUOTE (Dogmeat @ Apr 11 2009, 04:14 PM) index.php?act=findpost&pid=768733
I guess my question is, if the bog is caused by fuel starvation, wouldn't I want go INCREASE the size of my leak jet from the stock 40 to say, a 45 or so ... Why would I want to DECREASE the size of my leak jet down to a 35?

Also, if I don't have any play in my accelerator pump lever, why do I need to zip tie it?[/b]

the leak jet is actually the bypass circuit... when you jam the throttle, a rod is pushed down into the diaphragm of the accelerator pump, that pump pushes a burst of gas into the engine, when it pumps, there are two routes the gas can go, one route is up into the engine, the other path is through the leak jet and back into the bowl for recycling. so if you want more gas to go into your engine, you have to reduce the size of the leak jet. get it?
QUOTE (leveldrummer @ Apr 11 2009, 08:20 PM) index.php?act=findpost&pid=768875
the leak jet is actually the bypass circuit... when you jam the throttle, a rod is pushed down into the diaphragm of the accelerator pump, that pump pushes a burst of gas into the engine, when it pumps, there are two routes the gas can go, one route is up into the engine, the other path is through the leak jet and back into the bowl for recycling. so if you want more gas to go into your engine, you have to reduce the size of the leak jet. get it?[/b]
I s this true? it sounds legit. Hello everyone new guy here Hows it going
Im new here but just to let everyone know I am in full production of a pipe that will kick the stuffing out of any other pipe out there. They will be available in another two months I will stay in contact, pics coming soon
QUOTE (leveldrummer @ Apr 11 2009, 09:20 PM) index.php?act=findpost&pid=768875
the leak jet is actually the bypass circuit... when you jam the throttle, a rod is pushed down into the diaphragm of the accelerator pump, that pump pushes a burst of gas into the engine, when it pumps, there are two routes the gas can go, one route is up into the engine, the other path is through the leak jet and back into the bowl for recycling. so if you want more gas to go into your engine, you have to reduce the size of the leak jet. get it?[/b]
Yeah, I see what you're saying ...

I still don't understant though why I would need to zip tie my accelerator pump like you guys are saying, the bog isn't when I let off the throttle, it's when I stab it ...

there is no play between the two peices as it stands right now.
yeah, it fixes that bog when you stab it by making a bigger and longer jet of fuel squirt into the engine.

and you say there is no play... turn the wheel and at about 1/2 to full throttle the metal piece and the plastic piece start to have a gap. just zip tie it or bend the spring and then get a 35 leak jet. trust me.
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