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Discussion Starter · #1 ·
I have an 87 gsxr 750 with pods instead of an air box. At sustained speeds above 80mph the accelration starts to get weak, choppy and eventually the bike loses the power to accelerate at all and i have to pull over. As soon as i stopp giving it gas it stalls. It was almost like i had ran out of gas but this hap happened several times and gas was good every time. I checked my fuel filter but it looked clear, and when placed on prime it seemed like i could see fuel flowing freely down the tube. I cleaned the pods, but not well. however i popped one of the pods off while riding and it still happened so it doesnt seem that clogged pods are the reason (?) I've had the carbs cleaned about 700 miles ago (when i bought it) so it seems that shouldnt be an issue. ALso, after pulling over (on the highway in the shoulder, which always sucks) i can get the bike to run again if i just let it sit for awhile. But even then it may or may not run like nothing happened in the first place, as long as i keep it below 80mph give or take. I also have a fairly bad oil leak but i keep an eye on it and im waiting for winter to end to do something about it.

Any help is hugely appreciated!!!
 

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Are you saying that if you run at 60-70 mph, it will run fine all day? I knew a guy who had virtually the same problem on an older bike. The rings were sticking, and the engine lost compression when the bike got really warm. Try a compression check when it's cold and again after it's heated up.
 

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You're certain on the fuel-flow thing?

Wife of mine had an EX500 - would "run out of gas" when on reserve (with gas still in the tank) Fuel flowed just fine, or so I thought. Turns out, the fuel-passage in the petschlong wasn't drilled-through completely - had this tiny little hole for fuel on the reserve side.

A bit of quality time with a drill press and the properly-sized bit cured that problem.

I'm not sayin' that's the problem with yours: but it turns out it was with hers.
 

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Please remember your bike has a vacuum operated FUEL VALVE (same as a petc0ck) so check to see if you've got a vacuum leak at that junction, also, how does it run on "prime"? Since Prime bypasses the diaphragm and the whole vacuum process all together...
 

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Well, I considered using "petweiner", but surmised people might think I was talking about a Dachsund.
My first wife had THREE of those things, Oreo, Prissy, and Brandy. Prissy got excited and peed the floor every time we came home. Brandy had some sort of skin disease that left crumbs in the bed. It was like laying in Rice Krispies. Oreo had the habit of dry humping everyone who set foot in the house. Good times, goooood times.
 

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It's out of breath. Sportbikes depend on the airbox to pressurize the airflow and thus have continuous flow for the carbs. Find a used box and install it. Repeat your objectives and if it doesn't die you have figured out the issue. If it does die, I'd say your carbs need to be re-fitted with needles that actually work for you.
 

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I prefer Pet-tallywhacker myself, Irregardless it sounds like the float bowls aren't keeping up at high speeds. Pinched vent or damaged vacuum line to the pet-schlonger would be my guess.

Good advice about replacing the airbox and original flat panel filter, as a general rule removing or drilling the airbox or removing snorkles is a pretty good way to make your bike run like sh*t unless you replace them with other componants to do the same thing
 

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Discussion Starter · #13 · (Edited)
thanks for the help!! here's some more details

I don't have a vacuum tube, it's just a hole on top of the gas tank. I wish i did have an airbox but thats how i got the bike. I tried running the bike down 95 south today and i got a couple doxen miles or so but then it happened again. I pulled over and let it sit for a while. It wouldnt idel unless i opened the choke a bit- which would make on ethink it was the pods. But i cleaned them recently and i have tried pulling open the choke while riding and it still konked out. It sounds exaclt like a bike running out of gas when it does. It needs high RPMS for the phenom to happen. It's been idling outside my house right now for about 20 mins- put some carb cleaner in the gas tyank. Does any1 think it could be the carbs. Supposedly they were serviced less than 800 miles ago...
 

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Discussion Starter · #14 ·
Are you saying that if you run at 60-70 mph, it will run fine all day? I knew a guy who had virtually the same problem on an older bike. The rings were sticking, and the engine lost compression when the bike got really warm. Try a compression check when it's cold and again after it's heated up.
I have no idea how to do a compression check but no, the bike will not run fine at 60-70mph, it will just take longer to conk out.
 

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plugs? i apologize for my ignorance (only been riding bout a year) so i dont know what plugs exactly ur referring to but if u tell me ill look into it.
Sparkplugs.

You need moto-mechanical help.

You have one of three choices:

If you love the bike, but don't have much money, buy a Clymer manual at your local mom-&-pop moto-shop. Read it cover to cover. Do it again. Ask questions both here and at the shop. Become intimately-familiar with the bike, then buy a Factory-brand Jet Kit to fix it.

If you love the bike, and have grundles of cash laying-about, do all the above, but pay the mom-&-pop to fix it (or lay out even MORE cash to a "Dealer", who may or may-not fix it many-hundreds of dollars later).

If you're frustrated with the bike; Sell it and use the proceeds to buy another bike, being somewhat more-informed about purchasing any moto with half-assed "power mods" done to it, no matter how great a deal it might seem.

Choose Wisely.
 

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Discussion Starter · #19 ·
Sparkplugs.

You need moto-mechanical help.

You have one of three choices:

If you love the bike, but don't have much money, buy a Clymer manual at your local mom-&-pop moto-shop. Read it cover to cover. Do it again. Ask questions both here and at the shop. Become intimately-familiar with the bike, then buy a Factory-brand Jet Kit to fix it.

If you love the bike, and have grundles of cash laying-about, do all the above, but pay the mom-&-pop to fix it (or lay out even MORE cash to a "Dealer", who may or may-not fix it many-hundreds of dollars later).

If you're frustrated with the bike; Sell it and use the proceeds to buy another bike, being somewhat more-informed about purchasing any moto with half-assed "power mods" done to it, no matter how great a deal it might seem.

Choose Wisely.
I choose option A. I dont know if i LOVE the bike but i like it and i cant afford sh**. Been meaning to get the manual for a while, it's always better to learn in my opinion. But any bike i can afford will be "half assed" in one form or another. Otherwise i wouldnt be having these problems. But on the other side, couldnt i also go back to the airbox?
 

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I choose option A. I dont know if i LOVE the bike but i like it and i cant afford sh**. Been meaning to get the manual for a while, it's always better to learn in my opinion.
It's definitely not the "easy road". But, it has it's own rewards. Don't be afraid to ask questions here; we're smartarses, but mean well.

But on the other side, couldnt i also go back to the airbox?
Yeah, that would be "ideal", IMHO. If you can find one, and all the accoutrements that go with it.

But, you said this is an '87 model-year. I would think something that old MIGHT be a bit hard to come by. The next-best thing would be to cope with what you have in-hand.
 
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