wits end with bogging hesitation issue

Hi folks,I ride a 2007 1250 bandit.The bike has 49000 km on it and has always ran great but unfortunately lately after a ride of at least 1 hour or more anytime I try to apply power it almost feels like its running out of gas.I crank the throttle and it just cuts in and out. I am thinking if it was the fuel pump it would be a constant problem not after an hour.Up until that hour it runs great.
I brought it to a mechanic and he cant figure it out.I am not talking about a minor hesitation,its so bad that I couldn't even pass a scooter when this happens. If I roll the throttle on really slowly it doesn't do it.
I am at my wits end and don't want to get rid of it cause I love the bike when it is running well.
I read this entire thread http://www.twtex.com/forums/showthread.php?t=48828&page=2 and cant find any answers

Please if anyone has any idea as to point me in the right direction it would be much appreciated and THX for reading

It is still worth to look at gas pump (mesh AND filter).
What happened to me last year when I was on a tour:
Started bike up, everything was fine. Accelerated well, revs went up to red line etc. Then gradually it got worse. Top revs dropped and finally after a while they didn't go over 5000 rpm. Full throttle it would almost die and when rolling throttle very slowly it would gradually go up to 5000 rpm. I do not remember how long it took for bike from running OK to not running OK but there was a significant time delay. Not an hour tho. It was less and deterioration was gradual.
What was the reason:
I bought my bike crashed and I had to weld my gas tank. I failed to clean my tank well enough so mesh got clogged. I did clean everything before I went to tour but it was not enough.
Basically what happened was that when bike was not running the debris would sink on the bottom of the mesh and they would not clog the mesh. When bike started the gas flow would start pick debris up and they would start gradually clogging the mesh up to a point where bike would not rev more than 5000 rpm.
Since I cleaned the mesh and not the filter it happened again. Filter was full of debris and after cleaning the mesh it was a source for new clogging material and it all repeated.
It could happen with dirty gasoline also not just welding and grinding debris.
So my symptoms were exactly as yours and it was still clogged up mesh and filter. After thorough cleaning of the mesh and the filter everything was OK. It was not the greasy stuff that clogs mesh that usually causes the problems but fine debris that would settle on the bottom after the bike stopped running and would get picked up once bike was running.

Thx for the reply TONIS and the tank sat for an extended period with no gas in it and when I got the painted tank back I did notice some rust beginning to form.I remember seeing a thread on this site about the mesh cleaning process along with pics.So I will search for it thx so much Tonis_t

If my version is correct, then clean the filter so you can test it and then of course replace it. It doesn't cost much.

Oh, one tip I forgot earlier. When you have the back part of the fuel pump body where mesh is at your hand, I used regular tap water to flow large amounts of fluid at quite high pressure to flow through the housing/mesh opposite direction of gas flow. Tap nozzle (garden hose works too) sits quite nicely to the opening where tube connects that leads to throttle bodies. Cover the hole where pressure regulator sits with your finger and open the tap be careful, water will shoot out depending on your main water line pressure up to 10...15 meters. I submerged the housing to glass jar in acetone too kept it there and shaked it regularly alternating it to high volume/speed water flow opposite direction of gas flow. (acetone was in hope that it would dissolve any of the gooey stuff that usually clogs the mesh. Dunno if I had any or not. I did not use the wire method described in twt thread but everything works for me for a year now)
Worked very well. Instead of glass jar with cover if you have access to ultrasonic cleaner, that would be much much better than glass jar/shaking.

Hopefully it is as simple as derbies in filter/mesh and it will solve your problems.

Thx again Tonis I am gonna give it a go this weekend.You SIR are a gentleman

Here's a good step by step: http://nswbandits.forumotion.net/t1379-fuel-pump-fix

I did the cleaning of the filter and mesh screen it was pretty easy,I found that a proxy brush which is a brush used to clean the gaps between teeth works well got quite a bit of crud come out. None the less the problem still remains albeit the bike when not having the issues is running fantastic. It still did it just took longer to happen and happens much less.

Right after cleaning had about a 1/3 of a tank left filled it up then went for ride and it first happened with two bars left so pulled over at the first gas station filled it again and it stopped doing it.When down to half tank it started again only seems to happen when I hammer the throttle.

I have disconnected the battery to reset the ECU and see if that has any effect.

So any one have any suggestions

If it took longer to happen again then do the cleaning again and also clean te tank itself. If you didn't clean the tank then you didn't remoove the cause of the problem. Also you need to clean the little filter before pump. It took me few tries before i got everything clean enough that the problem didn't come back.

Tonis_T said:

If it took longer to happen again then do the cleaning again and also clean te tank itself. If you didn't clean the tank then you didn't remoove the cause of the problem. Also you need to clean the little filter before pump. It took me few tries before i got everything clean enough that the problem didn't come back.

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Thx again Tonis,I was thinking the same. The little filter you speak of was also cleaned I utilized a small toothbrush used to clean between teeth, worked like a charm first dip in it came up black LOL . I am going to order the sock filter new just in case. My only worry would be the o-rings and main sealing gasket hope they can withstand the removal and replacement multiple times.

Best regards

update: Thanks Tonis and Kewig seems that my problem is resolved and the bike is running better then ever.Just in time before my trip down to enjoy the pennsylvania twistys.

What was it? Just needed cleaning or something else too?
Glad you got things resolved

It was the fuel filter strainer and the smaller filter before the pump as you suggested. Cleaned the tank by filling with a little gas shaking it up then dumping and repeating multiple times. Also by doing another final cleaning of the strainer before reassembling the pump with carb cleaner spray can. I also disconnected the battery to reset ECU,I don't know if that had any effect but I've been out riding man times and still NP.

androx45 said:

It was the fuel filter strainer and the smaller filter before the pump as you suggested. Cleaned the tank by filling with a little gas shaking it up then dumping and repeating multiple times. Also by doing another final cleaning of the strainer before reassembling the pump with carb cleaner spray can. I also disconnected the battery to reset ECU,I don't know if that had any effect but I've been out riding man times and still NP.

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Well done!

Good job! I had to swap tanks on my '07 Bandit due to a crash last summer which involved swapping the pump assy to the newer tank. I had check all this stuff while apart and was kinda amazed that it was all still clean at near 70,000 miles and gas from all over North America had been ran though it. I guess the trick is NOT to let them Set Up. I have a friend with an 04 DL 1000 that set up for over a year and wouldn't start even. Sad thing is , it's still on his lift , apart , since '07.

thx to this site saved a few $ and gained some valuable experience....with my beloved bandit. Went out for a ride yesterday evening and was smoking my two buddies in the twistys. One with the zx14 another has the gixxer 1000 both humbled by the BANDIT................LMAO

androx45 said:

One with the zx14 another has the gixxer 1000 both humbled by the BANDIT................LMAO

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Wanna see something funny! A bunch of cruisers attempting to hang with a KLR on a ruff and curvy road.