Stalling sometimes

[Smick6]

Hawk problems on the way to work this am. So I recently did a rear brake resevoir delete and thru swing arm mod. That required me to remove the ground wire from the bracket the resevoir was on. This stalling problem (backfire and stalling but power still on) happened once after the mod. I took the ground lug back off, cleaned everything and reinstalled. Verified continuity with a meter. Checked spark and found all good. Fuel filter is clear. Drove it twice after that about 30 miles each time with zero problems.

This morning the same thing started happening. I was close enough to push it home. When it first happened today I pulled over and let it sit for a few minutes and started it back up. I didnt hear the aftermarket fuel pump tick even while pulling back the throttle so I felt it and it was really hot. Do they normally get that warm while running? I never had a reason to touch it when running. So I think when I get home I will pull the fuel line out, put it in a container and jumper the fuel pump just to see it flow. Problem is that its intermittent so I might just buy a new one.
I was thinking about doing a Mikuni pump swap. Anybody have one for sale?

Any tips or suggestions would be appreciated.

[Smick6]

I will check the fuel pump relay also.

[yorkshire]

Hi, can the hot pump be no fuel getting to the pump, just a guess

[Smick6]

Clear fuel line looked like it had gas in it. I was on the side of the rode and late for work so no time to really troubleshoot. Will be checking stuff out in a few hours hopefully.

[squirrelman]

do you hear the pump clicking continuously ?

[Smick6]

So got a little time to work on it and found a small leak in one of the hoses then I barely moved it and it became a big leak. Heading out now to try to find some new lines. Strange I never smelled it.

[Smick6]

do you hear the pump clicking continuously ?

squirrelman you are a Hawk whisperer. You totally helped me when I was dialing in my jets.
It does click continuously now. I replaced the line with the leak and it basically fell apart as I removed it. After a few minutes at idle I used a long screwdriver to help feel and hear the nonstop clicking.
If I remember correctly it should only click when bowls need a refill correct?
I will research this further shortly.

[squirrelman]

seems like poor fuel flow INTO pump, thats why its hot. pull off line to pump to check for flow. maybe blow air backwards into the line to clear debris, maybe clogged tank filter.

normally the pump will click once about every 15 seconds.

[squirrelman]

Hi, can the hot pump be no fuel getting to the pump, just a guess

exactly

[Smick6]

Got a bit more time for troubleshooting. Pulled off the outlet of the pump and ran a tube back to the tank. It pumps as expected. So fuel filter and pump are ok. Since I had a new pump and filter I threw it on for a test drive. I let it idle in the sun for 10 min before riding. Drove around in subdivision for 15 min about 25mph stop and go with zero problems. Went back home to grab the helmet to hit the road. Turned off bike and fired right back up fine. 3 blocks out to the main road and its 45mph to 55mph. Got on it a little and within 1/4 to 1/2 mile it bogged out.

One thing I noticed is the tank seemed to get way hotter than ever. It is 90 degrees here but I have ridden in this temp plenty of times and never noticed the tank get hot. The temp gauge stayed where it usually does so no overheating.

Pulled over for 10 min and it fired back up.
Got within 2 blocks of home then start bogging down so pulled over and pushed home.

No more time tonight or next 2 days for troubleshooting. Almost seems like fuel starving but pump works, petcock clear and hoses filled with gas. Will have to look into carbs and the tee in the fuel line for each carb. Will change all of the fuel line out first just to be sure one is not collapsing.

[squirrelman]

could be a tank venting problem or kink in a fuel line.

carry a spare sparkplug to quickly test for spark (without having to remove one) as soon as it quits.

[Fastmongrel]

I had a similar problem on an old BSA B44 it turned out after much checking of the electrics to be a bit of wax had got into the breather hole in the tank cap. Ten seconds with piece of wire cleared the electrical problems.

Proof that cleaning and polishing is bad for the bike

[6]

Got a bit more time for troubleshooting. Pulled off the outlet of the pump and ran a tube back to the tank. It pumps as expected. So fuel filter and pump are ok. Since I had a new pump and filter I threw it on for a test drive. I let it idle in the sun for 10 min before riding. Drove around in subdivision for 15 min about 25mph stop and go with zero problems. Went back home to grab the helmet to hit the road. Turned off bike and fired right back up fine. 3 blocks out to the main road and its 45mph to 55mph. Got on it a little and within 1/4 to 1/2 mile it bogged out.

One thing I noticed is the tank seemed to get way hotter than ever. It is 90 degrees here but I have ridden in this temp plenty of times and never noticed the tank get hot. The temp gauge stayed where it usually does so no overheating.

Pulled over for 10 min and it fired back up.
Got within 2 blocks of home then start bogging down so pulled over and pushed home.

No more time tonight or next 2 days for troubleshooting. Almost seems like fuel starving but pump works, petcock clear and hoses filled with gas. Will have to look into carbs and the tee in the fuel line for each carb. Will change all of the fuel line out first just to be sure one is not collapsing.

If it does it again as soon as you stop pop the fuel cap and listen for a "pssst" sucking sound. If it's struggling to suck air into the tank it can not pull the fuel out.


If that's the issue drill a hole in the gas cap, then ask nt650hawk to take it for a few laps to help set it up.

[Smick6]

More troubleshooting going on today.. Front plug.
20220620_090526.jpg

Rear

[6]

Rears look the same?