Hey, first post here. Let me start by saying that I have been through all 404 pages of the 4-stroke section and although there were some guys with similar problems, I couldn't get a definitive answer on my particular problem. There may not BE a definitive answer for my problem. If you've got 10 minutes to kill, read on.
· I bought this bike for my 15-year-old son in 2013 with plans to do some dual sport rides with him.
· I assume the bike has been “powered up” because the O2 sensor bung has been plugged
· It has an Arrow silencer and a Loudmouth air filter
· Stock dash is long gone, it has a Trail Tech Vapor instead
· Bike has been rock solid until January this year when the fuel pump failed to spin
My problem started with a fuel pump issue. The pump initially failed out in the middle of nowhere. I had all the tools I needed so I pulled the pump assembly out of the tank and plugged it back in to the harness to test it. I found that the pump was possibly choking on some debris, so I tapped the pump with a wrench and it started spinning. I put the tank back together and we rode for another 100 miles praying that it would restart after each stop. It did. I got the bike home and ordered a new fuel pump.
The first one I bought did not have a barb on the outlet. I had to resort to installing a compression fitting and hose barb on the short outlet nipple to keep the hose from blowing off the pressure side. With the added hardware needed to install the compression fitting and barb on the pump outlet, the fuel line and filter were being forced into the interior tank wall when I put the assembly back in the tank so I scrapped that whole system and bought another pump from Quantum Fuel systems. That pump already has the hose clamped to a proper barb with band clamps. I installed that new pump, verified that the pump would stay put and reassembled the bike. Everything was great, bike ran great. I registered myself and my son for the SDAR Desert Dash in February. We started the Dash and all was going well until we hit 90 miles. The bike started missing at higher RPMs. I switched with my son so I could ride it and see what the symptoms were. It seemed like ignition at that point in time so I stripped off the seat and tank and checked all the coil connections and spark boot connection. The bike ran fine after that for another 40 miles of high speed pole line road, then it stated missing all over the rev range. We nursed it to the nearest fuel stop and decided that it was too late to work on it so I slabbed it back to get the truck.
I ripped into the bike a couple of weekends ago and found that the in-tank filter provided with the Quantum fuel pump had malfunctioned. The paper element inside the filter had come loose and was bouncing around inside the filter housing. Once I saw that, I figured that the missing may have been caused by a clogged fuel injector so I pulled that out and soaked it/blew it out with air. I installed a new fuel filter, one that didn’t have the element rolling around inside. I also cleaned out the fuel line that runs from the tank to the fuel rail. I put the bike back together temporarily and it started up and ran fine. I rode it up and down the street, through all the gears and it was great. I brought it back into the garage after the test ride and prepared to button everything up, I removed the tank once again, loctited the FI fuel rail bolts, verified the mating of all connectors, put on the side covers and thought I was done. Once reassembled, the bike would only idle for about 10-15 seconds then quit. Further troubleshooting revealed the following: The pump spun/primed when the key was turned to the run position. The pump ran as it should after the engine started. After the engine stalled, the pump would shut off. I know this because I pressed my ear up to the tank while the bike was idling. If I whacked the throttle open, the bike would stall immediately. If I let it idle, it ran for about 15 seconds then quit, the pump would then shut off. I swapped back in the old intermittent pump and I got the same results. I pulled the injector out again, cleaned it, cleaned all the fuel lines again and still got 15 seconds of idling, then it died. I pulled the injector again and checked the spray pattern during the start cycle, and it looked like it is spraying plenty of fuel for the period of time that the start button is depressed. During this whole process I tried running with the gas cap on or off, I got the same results. At that point, even though it would have been very satisfying the push the bike into the back yard and burn it, I decided I should just turn out the lights and walk away.
This weekend I built a fuel pressure gauge assembly and installed it between the tank and the throttle body. I was curious if I had enough fuel pressure coming out of the tank. I installed the pressure gauge assembly on the bike and started it up. It ran great for as long as I cared to run it. The fuel pressure started out at 44 PSI and dropped gradually down to 41 PSI while the bike heated up. It would idle happily and when I whacked the throttle open, it acted like a normal motorcycle, no stalling like before. I did this test with the vent tube/check valve removed from the tank cap, so I verified that the vent hose and check valve were clear and continued testing. Still ran great. I then shut the thing down and pulled the pressure gauge assembly off and put the old fuel line back in place. I put the whole thing back together and took it for a ride. It runs great now. The only difference between this weekend’s results and last weekend’s frustration was that I tested the fuel pump output pressure by installing a test gauge. The bike is now running as well as ever with all the same components that it had when it wouldn’t run for more than 15 seconds. FYI, the bike would miss twice just before it would die.
I’m near certain that this thing will bite me the next time we haul it out to the desert. Has anyone had any similar symptoms? Was this a bad connection somewhere? Air Temp/Pressure/TPS? I cycled through all the electrical connections on the first weekend but I didn’t bother with them this weekend. Now it’s running great. Temp sensor seems like its functioning well, the fan starts at an indicated 212F on the Trail tech Dash.
I’ll listen to any comments or suggestions?
My son loves this bike. It’s been the perfect ride for him until now. We cover 100-200 miles on riding weekends and I’m not really looking forward to towing this thing out to the nearest road crossing the next time we go out.
Thanks,
Another New Guy
· I bought this bike for my 15-year-old son in 2013 with plans to do some dual sport rides with him.
· I assume the bike has been “powered up” because the O2 sensor bung has been plugged
· It has an Arrow silencer and a Loudmouth air filter
· Stock dash is long gone, it has a Trail Tech Vapor instead
· Bike has been rock solid until January this year when the fuel pump failed to spin
My problem started with a fuel pump issue. The pump initially failed out in the middle of nowhere. I had all the tools I needed so I pulled the pump assembly out of the tank and plugged it back in to the harness to test it. I found that the pump was possibly choking on some debris, so I tapped the pump with a wrench and it started spinning. I put the tank back together and we rode for another 100 miles praying that it would restart after each stop. It did. I got the bike home and ordered a new fuel pump.
The first one I bought did not have a barb on the outlet. I had to resort to installing a compression fitting and hose barb on the short outlet nipple to keep the hose from blowing off the pressure side. With the added hardware needed to install the compression fitting and barb on the pump outlet, the fuel line and filter were being forced into the interior tank wall when I put the assembly back in the tank so I scrapped that whole system and bought another pump from Quantum Fuel systems. That pump already has the hose clamped to a proper barb with band clamps. I installed that new pump, verified that the pump would stay put and reassembled the bike. Everything was great, bike ran great. I registered myself and my son for the SDAR Desert Dash in February. We started the Dash and all was going well until we hit 90 miles. The bike started missing at higher RPMs. I switched with my son so I could ride it and see what the symptoms were. It seemed like ignition at that point in time so I stripped off the seat and tank and checked all the coil connections and spark boot connection. The bike ran fine after that for another 40 miles of high speed pole line road, then it stated missing all over the rev range. We nursed it to the nearest fuel stop and decided that it was too late to work on it so I slabbed it back to get the truck.
I ripped into the bike a couple of weekends ago and found that the in-tank filter provided with the Quantum fuel pump had malfunctioned. The paper element inside the filter had come loose and was bouncing around inside the filter housing. Once I saw that, I figured that the missing may have been caused by a clogged fuel injector so I pulled that out and soaked it/blew it out with air. I installed a new fuel filter, one that didn’t have the element rolling around inside. I also cleaned out the fuel line that runs from the tank to the fuel rail. I put the bike back together temporarily and it started up and ran fine. I rode it up and down the street, through all the gears and it was great. I brought it back into the garage after the test ride and prepared to button everything up, I removed the tank once again, loctited the FI fuel rail bolts, verified the mating of all connectors, put on the side covers and thought I was done. Once reassembled, the bike would only idle for about 10-15 seconds then quit. Further troubleshooting revealed the following: The pump spun/primed when the key was turned to the run position. The pump ran as it should after the engine started. After the engine stalled, the pump would shut off. I know this because I pressed my ear up to the tank while the bike was idling. If I whacked the throttle open, the bike would stall immediately. If I let it idle, it ran for about 15 seconds then quit, the pump would then shut off. I swapped back in the old intermittent pump and I got the same results. I pulled the injector out again, cleaned it, cleaned all the fuel lines again and still got 15 seconds of idling, then it died. I pulled the injector again and checked the spray pattern during the start cycle, and it looked like it is spraying plenty of fuel for the period of time that the start button is depressed. During this whole process I tried running with the gas cap on or off, I got the same results. At that point, even though it would have been very satisfying the push the bike into the back yard and burn it, I decided I should just turn out the lights and walk away.
This weekend I built a fuel pressure gauge assembly and installed it between the tank and the throttle body. I was curious if I had enough fuel pressure coming out of the tank. I installed the pressure gauge assembly on the bike and started it up. It ran great for as long as I cared to run it. The fuel pressure started out at 44 PSI and dropped gradually down to 41 PSI while the bike heated up. It would idle happily and when I whacked the throttle open, it acted like a normal motorcycle, no stalling like before. I did this test with the vent tube/check valve removed from the tank cap, so I verified that the vent hose and check valve were clear and continued testing. Still ran great. I then shut the thing down and pulled the pressure gauge assembly off and put the old fuel line back in place. I put the whole thing back together and took it for a ride. It runs great now. The only difference between this weekend’s results and last weekend’s frustration was that I tested the fuel pump output pressure by installing a test gauge. The bike is now running as well as ever with all the same components that it had when it wouldn’t run for more than 15 seconds. FYI, the bike would miss twice just before it would die.
I’m near certain that this thing will bite me the next time we haul it out to the desert. Has anyone had any similar symptoms? Was this a bad connection somewhere? Air Temp/Pressure/TPS? I cycled through all the electrical connections on the first weekend but I didn’t bother with them this weekend. Now it’s running great. Temp sensor seems like its functioning well, the fan starts at an indicated 212F on the Trail tech Dash.
I’ll listen to any comments or suggestions?
My son loves this bike. It’s been the perfect ride for him until now. We cover 100-200 miles on riding weekends and I’m not really looking forward to towing this thing out to the nearest road crossing the next time we go out.
Thanks,
Another New Guy
