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GTBozak said:
Thanks for the tip Bob.

I didn't do the idle thing yet because I wanted to eliminate other possibilities. When you mentioned gas, I recently started filling up at a sunoco, just because they were selling 94 at the same price as the 92 across the street, but maybe that sunoco fuel has me all fouled up, maybe their gas was watery.

The bike sure is acting weird. Today I was pulling a uturn with extreme lean angle because I was trying to beat a line of slow traffic, and the bike cut off mid turn. It touched onto the peg , maybe even the turn signal before I could get enough grip on the upside bar to yank it back up. Only 27 miles into a new tank of gas.

On another theory, will overfilling the tank create too much vacuum as the fuel is spent causing the cutoffs? I've been filling the tank while sitting on the bike lately and it looks like more gas gets in there that way, but maybe that's not good. I hope it's that or the gas cap thing posted by Joshua109. I think they might be similar issues.
I always fill my bike with it in the upright position and top it off to the bottom of the filler neck and never had a problem as you have described. As someone else has mentioned the fuel cap should allow the tank to vent so you may want to have that checked. If you live in Pa. a Inspection Station has the equipment to check your cap. One other thing you may want to have checked is the "lean angle safety switch". Most large cycles, to include the 109, have a device that actually detects the angle of your machine. It is safety feature which is part of the fuel delivery systen and cuts power to the electric fuel pump should your bike be laid over. Your dealer should have a test procedure to check the switch.
 

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Mine's never cut out :bow: I run 95 octane minimum, normally 98 & sometimes 100. I never buy fuel from a 'no frills' station no matter how cheap. I've posted on this before, but if I even put an extra spoonful of fuel past the base of the neck I get fuel running down the tank once I ride off. This is with the bike on the stand at fill up.
 

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Some additional information on the "Lean Angle Safety Switch". Suzuki calls it a "Tip-Over Sensor" and it is located just below the gas tank mounting bolt and forward of the battery box. Page 5-11 of the Factory Service Manual has the following description "When the motorcycle tips over, the tip-over sensor sends a signal to the ECM. Then, this signal cuts OFF current supplied to the fuel pump, fuel injectors and ignition coil". From the problem you have described you may want to have the sensor checked.
 

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bob109 said:
Some additional information on the "Lean Angle Safety Switch". Suzuki calls it a "Tip-Over Sensor" and it is located just below the gas tank mounting bolt and forward of the battery box. Page 5-11 of the Factory Service Manual has the following description "When the motorcycle tips over, the tip-over sensor sends a signal to the ECM. Then, this signal cuts OFF current supplied to the fuel pump, fuel injectors and ignition coil". From the problem you have described you may want to have the sensor checked.
:bigthumbsup:

Thanks.

I it does sound like something electronic. I'll repost after dealer visit.
 

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Tip over or side stand switch *could* cause it, however the lean angle would need to be quite large to do so....... or the side stand switch contacts hitting due to *big* bumps.
 

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Still haven't taken it in. It was warm today in PA and I had absolutely no problems with the cutoff thing. I did not change my riding style, just changed gas stations so far. Hopefully it was just the gas. I'll find out if the ambient air temp had anything to do with it when Bruno and I go to breakfast this Sunday.
 

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guys there is only 1 way to properlly adjust the idle on your m109. this will help your stalling. throttle body sync. check the suzuki service manual!
 

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hey again also DO NOT adjust that bolt with jam nut under the l/h air filter can have bad results. it is desiged to hold the throttle plates of the bores of the throttle bodies. it is not an idle adjustment screw! to adjust idle you must perform a throttle body sync. idle speed is 900 rpms. warm.
 

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dear nasa you are right. however when you :joke:sync the throttle bodies on a 109 you are not adjusting the throttle plates. you adjust the air screws on the bodies. not the plates.
 

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For several weeks now my engine dies when I come to a stop. It seems to happen when I have half a tank or less of gas. Has anyone had this problem. Took to the service dept at my dealership and Suzuki told them to idle the speed up. I know from 30 years experience riding motorcycles this is not the solution. It's only masking the problem :cus:

Has anyone had this problem?
 

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Yes, mine has just started doing the same thing. Bought it new in 2014 (has only 18,000 miles), and has never done it before now. Does not happen when cold. Only happens after riding for a few miles, then dies when I pull in the clutch to down shift at an intersection.
 

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For several weeks now my engine dies when I come to a stop. It seems to happen when I have half a tank or less of gas. Has anyone had this problem. Took to the service dept at my dealership and Suzuki told them to idle the speed up. I know from 30 years experience riding motorcycles this is not the solution. It's only masking the problem :cus:

Has anyone had this problem?
Did you ever find a solution for the problem? Mine has started doing the same thing.
 

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Did you ever find a solution for the problem? Mine has started doing the same thing.
It's probably a dirty fuel filter. One of the first signs of them getting dirty is the bike quits when coming to a stop. You can get OEM for around $60 each or look on Ebay and you can find 3 for less than $10 shipped.

Great research BTW, this is one of the oldest threads on here. (y)

And welcome to the forum too.
 

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It's probably a dirty fuel filter. One of the first signs of them getting dirty is the bike quits when coming to a stop. You can get OEM for around $60 each or look on Ebay and you can find 3 for less than $10 shipped.

Great research BTW, this is one of the oldest threads on here. (y)

And welcome to the forum too.
Thank you. I'll order a new filter.
It's a terrible feeling for it to just quit running when you're surrounded by traffic.
 

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Give the fuel filter a try, its cheap enough and most are way past due to change their fuel filter anyway.
But if the bike is not bogging on you when you hard accelerate (needing the most fuel) and does bog when you are at idle (needing the least fuel) then chances are its not the fuel filter causing your issue.
If that is the case then have a look at your ISC valve under the tank. Follow the trouble shooting tips for this valve and circuit from the service manual.
The ISC valve is responsible for controlling the idle.
If you find nothing physically wrong with he ISCV, then you can also get a Suzuki dealer to relearn/reset the ISC scaling parameters using their SDS software.

BCS
 

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The engine never bogs when fuel is rolled on. It just dies when pulling up to a stop after a short ride (with a half-empty tank). While parked, it will run normally and never die.
This problem revealed itself after picking up the machine from the dealership. It sat there for four months while waiting for some body parts to arrive. During its stay, they never trickle charged the battery or occasionally cranked it up and let it run a few minutes.
I had no choice but to purchase a new battery from them (at full price), before I could get out of the parking lot. The tank was about half full and it started dying at every intersection I had to stop at, on the way home. I went back and told them what was happening, and they were completely baffled. After waiting three hours, they insisted on giving me a ride home (because they didn't have time to look at it), and to leave it with them, again.
The battery and fuel flow problems developed while in their "care", so I rode it home, and started researching the problem on the Internet.
I've ordered a new filter, round retainer clip, nylon strap and tank O-ring (to install, myself). If the filter changeout doesn't eliminate the problem, I'll be riding it to an out-of-town dealership.
Thank you for the technician-level information.
 

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On the fuel pump itself, there is a tube, the return tube, that is supposed to be routed to the inside of the boot. It helps keep the boot filled with fuel. I had this problem once, somehow the tube came out of it's receptacle on the boot. Once that happened, I started having issues like the OP has stated. Bike would still accelerate fine, but once the fuel level got around half tank, stalling issues popped up. Took the fuel pump off to replace it and found that. Put it back to where it's supposed to be, and the problem went away. That saved me from having to change the filter once.

Fuel returning via that tube is evidently under a lot of pressure. And apparently it just pushed itself out of the receptacle in the boot where it resides. I used a zip tie on it to make sure it stays put.
 
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If I discover that to be the problem, it'll be a great day. From looking at the diagrams, I know the tube you're describing.
Thank you for your great reply.
 
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