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Discussion Starter #1
This past week-end I took my 91' 900ss out for a ride and was excellent while at cruising speed of 65-75mph. Drove like 25 miles, arrive at destination, took a break 30minutes and headed back home. While on my way back home I decided to open her up and when I hit full-throttle I felt like a hesitation and heard like a bogging noise and the bike started loosing power! like if I was running out of gas! but I had a full-tank!! I immediately headed to the emergency lane and when I pulled in the clutch the engine died. Got off the bike, for some reason disconnected the vent hose that attaches to the top of the gas tank and tried to crank the bike and it started right up!!!:think: Now, I said... I better get going to see how far I can go before this happens again. So, I jumped on the bike and headed back home (I was a good 20miles away). I treated the throttle easily and didn't try full-throttle. Bike ran good. When I got like two blocks away from home I hit full-throttle to see what happened and bike responded excellent to full throttle without hesitation at all. I did hit it at least three more times on a 1st-2nd and-3rd gear full throttle sprint and bike didn't bogged or hesitate! :think: So, can somebody tell me why is this?? Is it pure coincidential? Honestly, now I am really worried to take her out on a ride and thinking it can left me stranded when you least expect it or need it!!!:mad: Any suggestions will be certainly appreciate it!

Thanks to all who respond to this thread.

Vickon:abduct:
 

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The first part was starting to sound like what happened to me when my timing belts slipped and my valves made contact with the piston... But then you started sounding nothing like the rest of my story after that... Either way maybe your belt just slipped a little bit but is still good enough to run. Check belt condition and tension maybe... It's probably something totally different, but this may be a place to start. Hopefully someone had your answer! Good luck!
 

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Discussion Starter #3
help...

Belts are new, I installed them, checked them and they are in perfect working order. Thank God that's not my case! My case should either be that little valve prior to tank vent port or dirty gas filter (but I always keep my tank with 93 octane good quality gas) and always full-tank! My regulator is maybe 9 month old and I have tested and it is in perfect working order too!:think:

Thanks anyway!
 

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Discussion Starter #5
help...

I already drained my tank completely and inspect it with a very high-beam led flashlight and no traces of rust either on the tank itself or the drained gasoline.
 

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Vickon, it sounds like you've already solved your problem and it's minor. Same thing happened to me when I kinked the fuel tank breather hose that goes into the top triple clamp. Could the one-way valve in the hose be backwards, or could the hose be kinked? It sounds like the tank is not getting air through the breather and this causes a vacume which starves the carbs for fuel; most noticeable at wide open throttle.
Good luck and let us know (I don't think it has anything to do with the cam belts).
Joe
 

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Discussion Starter #9
I connected the little hose with the valve back to the tank and moved the bike... just 2 or 3 minutes around the driveway without even starting the engine, later I unplugged the hose and it did a "hissing" sound like relieving a lot of air pressure!!! Is this normal? or is this the signal that the valve is not working? Once again, thanks everyone for your time and help!

Vickon:abduct:
 

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You sure you don't have the valve in there backwards? It only goes one way; the tiny arrow stamped on the valve should point away from the tank.
 

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Discussion Starter #11
Hi Joe-B, I haven't separated the valve from the hose never! So, there is no chance of it being reversed. Anyway, I will look today when I get back home to make sure the ">" arrow is pointing away from tank as you suggest. Once again, thanks! Is there a way to test such little valve??:think:

Vickon:abduct:
 

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Hi Joe-B, I haven't separated the valve from the hose never! So, there is no chance of it being reversed. Anyway, I will look today when I get back home to make sure the ">" arrow is pointing away from tank as you suggest. Once again, thanks! Is there a way to test such little valve??:think:

Vickon:abduct:
Yes. Take it off and blow through it with your mouth. You should be able to blow into the tank (opposite the arrow), but not out (with the arrow).
Joe
 

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Discussion Starter #13
So... just to be on the same page! The arrow is supposed to be pointing away from the tank? I can blow from both ways... but when blowing from one side sometimes it feels like a clicking loose part inside of the actual valve. Sometimes air flows both ways and sometimes it doesn't:think: I disconnected completely the hose and cranked the bike up and it started but when I rev it around 3K it kind of like wants to bog a little (not completely clean) but after it passes the 3K rpm range it is pretty clean and revs all the way up to 8K flawlessly! ?? It's driving me crazy!!! I don't know what to do or replace! What happens if I just connect the hose eliminating such valve? The fuel filter was replaced about a year ago. In that year I may have put 4K miles (maybe tops)!
 

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Vickon - if you decide that you want to test that stuck breather valve theory by swapping it out with another one I'm down in Plantation.

Kaput
 

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Discussion Starter #15 (Edited)
Thank you very much kaput! I really appreciate it! but from where I am it's kind a long trip and honestly I'm afraid it will let me stranded again and that it wouldn't start! Can you please tell me where is the pointy arrow facing? is it pointing towards the gas tank or away from the gas tank? Once again, thanks kaput! I really appreciate your help! We will certainly get together soon!



Kind Regards,

Vickon:abduct:
 

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Thank you very much kaput! I really appreciate it! but from where I am it's kind a long trip and honestly I'm afraid it will let me stranded again and that it wouldn't start! Can you please tell me where is the pointy arrow facing? is it pointing towards the gas tank or away from the gas tank? Once again, thanks kaput! I really appreciate your help! We will certainly get together soon!



Kind Regards,

Vickon:abduct:
Vickon, (as I said in an earlier post) the arrow should point away from the tank. You should not be able to blow both ways, only into the tank. That's because the purpose of the valve is to let air into the tank as the fuel is used up, so you don't get a partial vacume in the tank and starve the carbs for gas. The reason you should not be able to blow through it away from the tank is that the valve is supposed to close in that direction, so gas doesn't squirt out when you put on the brakes, or when the tank is full. You can run the bike without the valve, but I wouldn't if the tank has much gas in it. Without the valve, watch out for gas squirting out of the breather hose through the bottom triple clamp onto the motor, and possibly the rear wheel. If you ride the bike for a few miles and stop and open the tank and you hear a "woosh," like air is rushing in, then it sounds like the valve is the problem.
Joe
 

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Discussion Starter #17
Thanks again Joe-B, I was looking at old pictures of my bike and since the valve has a line around one of the sides I was able to find out which way the valve actually was prior to having this problem. I discover (based on the pictures) that the valve if it is how you say it is, has been reversed all of these years! and now I recall that a couple of times when I filled up the tank to the top when I arrived at a destination I would smell a very strong gasoline odor and noticed that some gas had been squirted off from the breather hose (bottom), therefore confirming your theory that if mounted the other way and valve working properly I should not experience this. So, if someone has one of these valves that could sell I will appreciate it!

Once again, thanks Joe-B! I have one last question regarding this issue...:think: Like I said before, I completely disconnected the hose from the tank and crank the bike up. It started right up, but when it got to the 3K RPM range I noticed it was not clean! but when I give it more gas all the way up to the 8 to 8.5K RPM it would rev cleanly! Why??:think: Anything else I should check?

Thanks!

Vickon:abduct:
 

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Thanks again Joe-B, I was looking at old pictures of my bike and since the valve has a line around one of the sides I was able to find out which way the valve actually was prior to having this problem. I discover (based on the pictures) that the valve if it is how you say it is, has been reversed all of these years! and now I recall that a couple of times when I filled up the tank to the top when I arrived at a destination I would smell a very strong gasoline odor and noticed that some gas had been squirted off from the breather hose (bottom), therefore confirming your theory that if mounted the other way and valve working properly I should not experience this. So, if someone has one of these valves that could sell I will appreciate it!

Once again, thanks Joe-B! I have one last question regarding this issue...:think: Like I said before, I completely disconnected the hose from the tank and crank the bike up. It started right up, but when it got to the 3K RPM range I noticed it was not clean! but when I give it more gas all the way up to the 8 to 8.5K RPM it would rev cleanly! Why??:think: Anything else I should check?

Thanks!

Vickon:abduct:
:think:...I dunno!
By the way, remember there is also a fuel overflow hose which begins under the gas cap and exits under the clutch. If this overflows it just means you overfilled your tank or the tank got hot and the fuel expanded. It has nothing to do with the breather hose with the valve that sticks down into the top triple clamp.
Joe
 

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Discussion Starter #19
Well... I flipped the valve pointing away, cranked the bike up and took her for a ride. Went to my "favorite testing spot" a good, practically abandoned street that heads to a dead end but at the same time is very clean and well paved.:D So, I opened her up all the way from cruising speed to full throttle and reaction was perfect! :eek::D Never a hesitation, missing and of course front end wanting to head up!:eek: I did this like 5 times, shifting up, down, cruising, then full-throttle and bike responded perfect at idle, at 3K, at 4,5,6,7,8 all the way to the red line! Then when I was at an almost stop I pressed hard the front brake (to test if any gas would squirt out) and no gas smell at all and no gas spill or overflow at all! :D Well, I guess that was it! or maybe an electrical gremlin???:think: I hope not! I have never had an electrical problem with my bike! other than replacing the "voltage regulator" which I had never replaced since I got the bike (years)!!!

Thanks Joe-B and kaput and all the members who filled in and gave their opinions, ideas and suggestions!:) I really appreciate this forum and the excellent group of members in it! :D Thanks!! hopefully I won't come back (at least regarding this problem) again! Lol.

Vickon:abduct:
 
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