Noisy Hacker

Steve
I am also flying a Sebart Wind 110 and have been using the A50-16L motor.
I have had 2 motors which went noisy after not that many flights, maybe 15 or so.
I have not had the start up bang that you describe however.
I have also read about others having A50-16L problems on the RC Universe forum Pattern flying / Electric / Wind110

http://www.rcuniverse.com/forum/m_7905478/mpage_1/key_/tm.htm

Hope the links work

Also take a look at this which shows the problem on Youtube someone posted.

http://www.youtube.com/watch?v=onzZA5Z-EnQ

I started flying Intermediate in Scotland and one of the guys up here was telling me he thought my motor bearings were worn.
However after replacing the shaft and bearing it turned out to be this issue where the stator to bearing carrier locking pin comes loose.
I have emailed Hacker whose response is to send the motors back to Germany for them to examine.
In fairness they have communicated with me directly and I'm told Rainer Hacker himself is involved.
I am reluctant to send them to Germany since I have repaired one myself by using epoxy on the stator to carrier.
This worked and you can tell before even powering up the motor by the removal of the growl and noise when turned by hand.
I suspect there may be a design or tolerence issue with this motor at Hacker. It also could be a Wind application issue - cooling maybe.
I have an A50-16S (short version) which has worked for 2 years in my Angel 50 and sounds as good as the day fitted.

Because of the 16L problem I have changed over to a Scorpion motor S4035-250kv and running on 8s.
So far so good after about 30 fllights but I think the Hacker has just the slight edge on 8s using APC 18x10E.
Some of the other guys are using the Scorpion on 10s but I read that some have thrown magnets so I've stuck with 8s.

There are a vast amount of discussion on the RCU forum about the Wind and it's motors - take a look.

Hope this helps
Regards
Colin