Premium member. 2007 Harley Davidson Ultra Classic. When I first start out on the bike, she will backfire when down shifting and cut off when coming to a stop with the idle dropping from 10,000 to 0. After riding for about 10 miles, this problem usually subsides and she idles fine around 10,000 rpms. Any suggestions?
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Back firing when down shifting is probably decel popping. This is caused by a lean condition. If you have a Power Commander or Vance & Hines FP3, you can add fuel @ 0% throttle. The FP3 also has an auto tune feature and another section designated to decel popping. As for the m/c stalling – Check for trouble codes and check for an intake leak.
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http://www.fixmyhog.com/video/custom-efi-mapping-installation-001395/
http://www.fixmyhog.com/video/vance-and-hines-product-review-007293/
http://www.fixmyhog.com/video/vance-and-hines-fuelpak-3-install-007295/
http://www.fixmyhog.com/video/troubleshoot-with-harley-error-codes-008010/
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My Dyna was backfiring yesterday, then I heard a loud pop and the oil dipstick popped out…what caused that to happen
Hi Tyrone,
I’d love to submit your question to our experts! Could you please provide the bike’s year for us first, please?
Thank you!
Sincerely,
Julia
Fix My Hog Video Membership
1990 Sportster 883, at first seems to hesitate when applying throttle till it warms up. Any thoughts
You may have an intake leak. We suggest that you remove, clean, & inspect your carburetor.
Replace intake seals & flanges if needed.
CARBURETOR
https://www.fixmyhog.com/video/stock-harley-carburetor-tear-down-007190/
https://www.fixmyhog.com/video/harley-carburetor-rebuild-007192/
https://www.fixmyhog.com/video/twin-cam-harley-intake-seals-replacement-008713/
-Mark
Fix My Hog
10,000 RPM. At that speed the engine should have popped, not the exhaust
Hmmm… 10,000 rpm idle huh? Well seems to me like you’re revving it a tad too high LOL….
Are you going to have these fixes put on paper for us?
There are other problems that may cause this and do not leave a trouble code! I have a 2007 softail custom that would stall when I stopped and sometimes the idle would move to 1400 – 2400 rpm’s. When I turned off the ignition then restarted, the problems cleared, no trouble codes. This has gone on since I owned the bike from new. No help from HD since they could not repeat the problems and no fault codes! Recently, I met a rider who had similar issues and asked if I had experienced them. He told me he found out HD had a bad batch of TPS modules, (Throttle Position Sensor), and had his replaced and has replaced and the problem has never returned. I had mine replaced and also replaced the cylinder head temperature sensor and the issue has not returned.
I would like to know whose bike idles at 10,000 rpm’s?
It’ obvious he meant 1,000 rpm.
When I crank my 04 Road King, the engine jumps to around 2,000, sometimes 2,200 rpms. After 2-3, 3-4 or so, minutes, it starts eventually backing down slowly to where it should be: 1,000 rpms. I cant figure out what is the issue. Diagnostic shows no codes. Ive cleaned IAC sensor. . .. no change. Not sure how to check TPS, except simply to replace . Any advice? Thanks