heat related power loss

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simmonsk133
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heat related power loss

Post by simmonsk133 » Sat Jul 25, 2015 2:07 pm

Hi,
2011 Gear Up. Starts great, pulls and runs great, then after about 7 to 10 miles, a few backfires and dies.
Restarts ok but when revving it cannot move without stalling. Tank cleaned, filters cleaned, carbs cleaned,, no help.
After tow home, started next day OK. Ran good 5 miles and died again. After cooling and over revving and taking a 1000 miles off of clutch , got home.

Replaced HES. Same thing. This sucks. Is spark coil next??? Headlight is bright, starter is fast.
Thanks. I will post results.
2011 Ural Gear up.

gobium
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Re: heat related power loss

Post by gobium » Sat Jul 25, 2015 2:13 pm

Coil?

PineyMountainRacing
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Re: heat related power loss

Post by PineyMountainRacing » Sat Jul 25, 2015 2:14 pm

Heat can certainly affect electrics and ignition, but a little more history on the bike. Was it running fine up until recently or did this problem start all of a sudden? New bike to you or you've been running it for awhile? Did the problems start after you serviced or worked on it?

Jetting changed recently? If it's too rich it might start cold but load up as it gets warm.
Air filter oiled recently? Easy to over oil the filter.
Last valve and ignition timing check?
'12 GU

simmonsk133
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Re: heat related power loss

Post by simmonsk133 » Sat Jul 25, 2015 3:07 pm

Thanks for help. Air cleaner cleaned and re oiled . Not ridden wet. Stock jetting although have new jets and screws from Holowpaw. Owned since New. Problem started suddenly. 8500 km. Valves are good.
Thanks
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URAL CT
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Re: heat related power loss

Post by URAL CT » Sat Jul 25, 2015 3:31 pm

Wazz a "HES"???
Cats still in place? Any upgrades done, like air filter, air box, muffler, ignition, etc..?? Check for vacuum leaks too.
My guess would be a defective coil too as Gobium suggested. Good Luck!
CT
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Albuquralque
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Re: heat related power loss

Post by Albuquralque » Sat Jul 25, 2015 4:40 pm

Coil or halls sensor....
"Put a little gravel in your travel"


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rivers
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Re: heat related power loss

Post by rivers » Sat Jul 25, 2015 5:01 pm

Coluralado wrote:Coil or halls sensor....
+1
That'd be my first guess and avenues of exploration.
Joe
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Snakeoil
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Re: heat related power loss

Post by Snakeoil » Sat Jul 25, 2015 5:27 pm

Tank vent plugged? Easy to check. Open the cap and if it starts running fine again, you found it.

Fuel petcock screen plugged? Crud in the tank plugging petcocks? But my money is on tank venting if ignition proves okay.

regards,
Rob
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Re: heat related power loss

Post by thumper05flstsc » Sat Jul 25, 2015 6:13 pm

I had same problem. New HALL sensor and no more problem.
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Re: heat related power loss

Post by Msblu79 » Sun Jul 26, 2015 4:49 pm

If it's possible pull the plugs after it dies and see if they are wet or dry. Wet or blackened plugs indicate electrical issue, dry clean plug is fuel starvation for some reason.
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Re: heat related power loss

Post by S 854 » Mon Jul 27, 2015 6:06 pm

simmonsk133 wrote:... Air cleaner cleaned and re oiled .
Did this problem start before or after you cleaned and re-oiled your air filter?
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simmonsk133
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Re: heat related power loss

Post by simmonsk133 » Tue Jul 28, 2015 12:12 am

Hi, No mods, except for Hellas headlight and high temp socket. Plugs at shut down were damp. Fuel petcock and carbs cleaned after first shutdown. HES is hall effect sensor. I replaced it after first shut down. It does not seem to help. Air cleaner done after first failure. Rode it a bit this weekend. 95f about 5 miles each trip. Will take coil with me next weekend and a big bottle of water and see if I can get it to fail in 30 miles or so. Before it gets hot it sounds and runs better than new. Auto zone has plugs on sale. Got 8 so I will be ready to read plugs at rejet time.
Is the coil hard to replace on the side of the road? I just don't want to pull tank on a hot motor.
Thanks until weekend...Ken
2011 Ural Gear up.

Brian Crean
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Re: heat related power loss

Post by Brian Crean » Tue Jul 28, 2015 7:04 am

The dying after warm-up is indicitive of various electrical faults, but the one that raises it's ugly head the most like this has been the coil. In the past, it's been mostly the type IV&V ignition, with the coil under the front cover going south when it got warm.

simmonsk133
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Re: heat related power loss

Post by simmonsk133 » Fri Aug 30, 2019 1:33 pm

I just realized that I never closed the loop. Gobium nailed it. The coil was failing when it got hot. I got another from Holowpaw and not have miles on it. HES is now in spares box. Thanks.
2011 Ural Gear up.

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