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Discussion Starter #1
My 11 Strom began to momentarily hesitate at highway speeds a couple weeks ago. During my last ride the brief cutting out of the motor happened more and more and I suspect a clogging fuel filter. I'll probably do the three key turn check. I have a few questions for those familiar with the process.

I think it would be best to replace the mesh screen and the various o rings. A little expensive, but ok if it is best.

I plan to use a wix filter and the necessary type fuel line for the bypass, but wondering if the existing connectors can be used/transfered? Or do we use four small hose clamps?

I saw a photo of what appears to be the same fuel pump and reservoir, but still not sure of the exact location to drill the 3/16s or so opening.

Bike starts up ok, but will hesitate when the throttle is cracked open.
 

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If all you're getting is a little hesitation I'd be looking at the plugs before the fuel filter. My filters were toast with less than 10,000km on it, but it had been allowed to sit for a long time with stale fuel in it before I got the bike and things were badly gummed up. Don't use mileage as any indication of the state of the filters, it only takes a single tank of sufficiently bad fuel to block them.
 

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It actually depends on the quality of the fuel you have been using, and whether you keep the bike outside or indoor. If the bike has been stored outside, Open the gas cap when the fuel tank is empty, shine a flash light in there and have a look at the condition of the fuel tank and also the fuel pump mechanism. If there rust and corrossion, I would go ahead and do the fuel bypass.

I did the bypass on my bike and it had 30k miles. My daughter's Gladius needed the fuel bypass at around 16k miles because her bike was stored outside and the condition of the tank was not too great.
 

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I think it would be best to replace the mesh screen and the various o rings. A little expensive, but ok if it is best.

I plan to use a wix filter and the necessary type fuel line for the bypass, but wondering if the existing connectors can be used/transfered? Or do we use four small hose clamps?

I saw a photo of what appears to be the same fuel pump and reservoir, but still not sure of the exact location to drill the 3/16s or so opening.
If you're that deep into the bowels of the bike, it's best to change things like o-rings as a precautionary measure. The labour costs - even if you do the work yourself - typically far outweigh the cost of these items.

You can apparently use the existing connectors but you need to be very, very careful when taking them off the existing fuel line. Use side snips to cut through the fuel line about a cm from the connector, and then carefully cut open the fuel line in the direction of the connector.

I decided not to do this. The appropriate set of Dorman connectors (800-081, Amazon.com: Dorman 800-081 Fuel Line Quick Connector for 5/16 In. Steel to 5/16 In. Nylon Tubing, Pack of 2: Automotive) is just over 10 dollars and that was worth the peace of mind for me.

As far as the location of the drill hole, just take out the pump, watch the photos in the threads on here and on VSRI, and match them with your pump. It will all become clear.

You will need the appropriate length of fuel line (50 cm?) and four hose clamps. Two for the connectors and two for the fuel filter. I bought this: https://www.amazon.com/gp/product/B0006302JA/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&psc=1 and used four of the small (black) clamps. But honestly, any appropriately-sized FI-spec hose clamp can be used. If you go to an automotive store near you and specify FI hose and FI hose clamps you should get the right stuff.

Oh, and while you're this deep into the bike anyway, the same diameter fuel line is also used in the fuel delivery pipe assembly. This fuel line will eventually start leaking, so you might just replace that as well. If you get the hose clamp pack that I referenced earlier, you've got sufficient hose clamps anyway, and you'll likely have the 3 cm or so of fuel line left over anyway. Just be careful when you remove that fuel delivery pipe assembly as you'll likely pull the injectors out with it. When you reseat the injectors, make sure you don't damage the rubber ring ("cushion") between the injectors and the throttle body.

Bike starts up ok, but will hesitate when the throttle is cracked open.
This is weird and may be indicative of another problem. The clogged filter problem typically only manifests itself at around 5000 RPM or when accelerating hard (high fuel flow) but should not have any consequences for idle/low power performance. Hesitation when the throttle is cracked open from idle is typically related to a TPS (Throttle Position Sender) problem - either one that is broken/worn, or one that is not adjusted properly. And the problem may be influenced by a wrongly adjusted idle (needs around 1300 RPM when warm) or an out-of-balance throttle body - so you need to do a Throttle Body Sync (TBS).
 

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Discussion Starter #5
Thanks for the replies fellow Strommers. I did the quick fuel flow test this morning and after three cycles I got 350 ml, or 12 oz. of gas so the flow seems ok. I don't think the spark plugs are fouled, but a loose connection may be a concern. The gas looks like urine with a greenish tint so I will run thru the two or so gallons and see if a refill helps.
The gas tank looks very clean inside, there is a little rust around the area (outside, under tank) where the fuel pump is bolted to the tank.
I have not done a TBS on this bike yet, but I do them on my FJR with a Carbtune gauge so I will be looking into that procedure.
 

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Discussion Starter #6
I pulled the tank and dumped the fuel, but the problem persists. The bike is not rideable due to the cutting out of the motor when accelerating from a stop. In other words, between two and three thousand rpm the motor sputters before revving up and going again.
Seems the pump is ok, and the gas was ok, so now I'm thinking the throttle position sensor may be worn.
By the way
Does anyone know if the secondary (I presume) throttle mechanism sits and rotates freely? The first set that the throttle cable attaches to seems ok, but the other set just stays wherever it is moved/rotated to.
 

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I pulled the tank and dumped the fuel, but the problem persists. The bike is not rideable due to the cutting out of the motor when accelerating from a stop. In other words, between two and three thousand rpm the motor sputters before revving up and going again.
Seems the pump is ok, and the gas was ok, so now I'm thinking the throttle position sensor may be worn.
By the way
Does anyone know if the secondary (I presume) throttle mechanism sits and rotates freely? The first set that the throttle cable attaches to seems ok, but the other set just stays wherever it is moved/rotated to.
The secondary throttle plates are supposed to move when you turn on the bike, full open then to fully closed. If you turn the key to 'on' with the covers off (so you can see them) and they don't move then you have a problem.
 

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Discussion Starter #9
I lifted the fuel tank and moved the secondary throttle down by hand and then turned the key. The throttle mechanism moved all the way up, and probably down, and then I started the bike to observe what the secondary does when twisting the handlebar grip. Seems ok, but I will look into lubing the linkage and whatever else is recommended.

I read another post that said to twist the throttle fully several times (bike not running) when the symptoms described earlier (hesitation from a stop, etc.) occur. I am happy to say that this method worked to eliminate around 90% of the issue. Rode 20 miles or so. I ordered a replacement (oem) TP Sensor on Monday and waiting for it to ship. The problem I had is that the parts shown on Bike Bandit and Partzilla do not make a distinction between the TBS and the STBS. Seemed I was required to buy two at Partz while BikeB allowed for one. I will get back to you all on that one.
 
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