Wtf? @ 4000rpm

Single & twin cylinder model BMW Airhead specific discussions
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Googledave
Posts: 10
Joined: Sun Nov 13, 2016 8:39 am

Wtf? @ 4000rpm

Post by Googledave » Sat Nov 19, 2016 2:07 pm

Hi all, I'm pulled over on the side of the road on my new to me r50/5 with a retrofitted 75/6 motor in it and dyna111 electronic ignition. I've ridden 30 miles and decided to pull over and check out the sights.. I'm stopped about 30 mins and start going again except she starts to stumble thru the revs. I pull over shut her off. Star her up and stumbling is gone... start riding everything is perfect until 4000 rpm where she then stumbles and the alternator light starts flickering.. I pull over rev her to 4000 and stumble and flicker. Above 4000 and it goes away... wtf? Carbs were completely rebuilt 100 miles ago. New spark plug wires, battery, 4 gauge battery cables... ground connect cleaned and paint scraped off frame... this just started today... any ideas?

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bbelk
Posts: 1721
Joined: Wed Aug 04, 2010 2:13 pm

Re: Wtf? @ 4000rpm

Post by bbelk » Sat Nov 19, 2016 5:58 pm

Float levels?
1975 R90/6
1979 R65

Googledave
Posts: 10
Joined: Sun Nov 13, 2016 8:39 am

Re: Wtf? @ 4000rpm

Post by Googledave » Mon Nov 21, 2016 3:52 am

Okay first off I posted this incorrectly it should be under post 70's forum. Second I found the issue! It was the contact at the ignition switch. As the bike got up too 4000rpm the contact would vibrate and caused a bad connection, to the point that it drained the battery. Anyway a little bending of the contact and a jumpstart from a friendly farmer and she's all good.. thanks!

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