75 r90/6 FUSE VALUES?

[Rohls]

Thanks for the responses.

I have two 8A fuses in there; so that is confirmed.

The fuse for the brake light and turn signal circuit blows after I ride it for about 10 miles stop and go traffic. I just replaced my turn signal relay with a 'cheaper equivalent' (~$90 OEM was a little much) from an auto store; could this be causing the issue? The fuse/relay blew is the reason I changed it (visible burnt portion on the relay).

Any thoughts? It would be nice to stop having to replace my fuse every ride...or just live without a brake light....grr..

Thanks!

Nick

[Rohls]

Ideas which part of the circuit could be crappy...?

Thanx

[Deleted User 287]

I'd like to know, if one changes over their Euro fuses to blade-type, do you go with 5-amp or 10-amp?

A la Airhead (the late Bill Emory)










Yes, for those that didn't know Bill, he had a glass eye (or a couple of them) and this is one he had made special.
No photoshop here.

[Airbear]

Ah, an interesting coincidence – it was in this week three years ago that Bill died.

I've just fitted blade fuses to Brunhilde - and went with 10 amp. By the way, you don't need the fuse holders - standard female 'spade' connectors fit straight on to the fuse terminals - saves some dollars and a tiny bit of real estate in the bucket.

Nick, how is your search for a solution going? It’s hard to suggest a course of action because of the intermittent nature of the problem. I can only speculate that if the replacement flasher unit is good then the problem lies with an intermittent short to ground, possibly in one of the indicator pods or maybe in the handlebar switch. Probing about with a continuity tester while wiggling wires might find something. Of course it could be anything on any circuit supplied by that fuse (green/black wires). This includes the instrument pod, starter relay and horn, as well as the brake light and indicator circuits. Where does one start? There are some electrical ‘gurus’ who frequent Boxerworks – hopefully one of them will drop in soon, if only to let me know that my reasoning above is useless.

In the meantime, keep bumping this thread and try to narrow down the symptoms – maybe go for another good ride on back roads with a pocket full of fuses noting exactly what circumstances cause the fuse to blow – is it when you are braking, or using the indicators, or just when things get hot?

[Rohls]

Thanks! I'm not the best at these electrical issues, though the good ol' airheads are truly hard to beat in terms of 'simplicity', so I may just stumble on the answer...

I'm thinkin' my whole problem may lie in the auto flasher I stuck in there...(trident Stant...I think..550?). I'd love not to buy the stock one...anybody had luck with this 'cheap' fix?

Nick

[SteveD]

A gentleman.
3 years! Time flies.

[Airbear]

I'm thinkin' my whole problem may lie in the auto flasher I stuck in there...(trident Stant...I think..550?). I'd love not to buy the stock one...anybody had luck with this 'cheap' fix?

Nick

It is a common fix to use a different flasher unit, and there is a list somewhere of alternatives that work, but I can't remember where it is. My old girl has a non-OEM unit, but there are no identifying marks on it. It only uses 3 wires - no earth (brown wire).

Ah, I've just done a bit of blundering about in Snowbum's site and found this -

"After the /5, the electronic flashers are a bit complicated inside. There are three different uses/types of these flashers. On the early version flasher relays, there is a terminal 49G, which has the same function as 49a on later relays. Early flashers had the indicator lamp on terminal C, later ones had the same type of function, but the terminal is now marked KBL.
ALL of the flashers from 1974 can be replaced very similarly with such as the Tridon EL13..or HD13....and similar. If your motorcycle has TWO indicator lamps (one for left, one for right), then there is NO connection to "C" or "KBL", and you need NOT be concerned about making that connection when substituting an aftermarket flasher relay.

The BMW flasher is rather pricey, and has special indication when a lamp burns out. You loose that when installing an aftermarket flasher relay, no big deal at all, as far as I am concerned. It is possible to rather easily add a piezo tone unit to any of the flasher setups. These don't use the brown ground wire that BMW's flasher relay does.

A recently recommended substitute is the Blazer (or, Tridon/Stant) flasher. The model used was 550, which is a thermal flasher, but handles the BMW lamps just fine, and would even handle extra lamps, such as on a trailer or hack. An electronic unit could also be used. I recommend that for the /5 you use the thermal flasher, it is easy to connect, and for /6 and later, you use the mentioned EL13 or HD13 or equivalent.

Do NOT use the solid brown wire that BMW had in its connection to the original flasher relay (1974+). Connect the old wire that went to KBL or C to the flasher P terminal. The BMW wire for this is probably Black/White or green. The aftermarket flasher relay probably has a terminal marked X, that goes to the +12 power, the old wire connected to flasher terminal 49, likely was green/black. The turn signal output of the new flasher relay is L, for LOAD, and is likely green/yellow.

Connect the P (which stands for PILOT lamp) terminal to the indicator lamp (usually a green wire); the X terminal to the +12 power (old terminal 49 wire, green-black); and the L terminal to the load (old terminal 49a, green-yellow). If you have two INDICATOR lamps, don't connect to the P terminal."

Stolen from Snowbum's (Robert Fleischer) site http://bmwmotorcycletech.info/electricalhints.htm

I hope that offers some help. I think it implies that the Stant 550 should work, but the EL13 or HD13 is preferred.

[ME 109]

To Bill, I raise me glass.
I used to talk to Bill sometimes when ordering parts from Munich Motorcycles.

[Rohls]

Thanks for the replies on the fuse issue. After some tinkering, I wrapped up any wires going to and from the flasher (non-OEM), replaced the fuse and headed out for a ride....300 miles later all seems fine. I believe the root cause was the flasher jumping around (not securely fastened to anything). my best guess as I touched nothing else in the bucket...

Till next time! Cheers!

[Airbear]

OR, she fixed herself. They do that sometimes, when faced by the alternatives.
Enjoy the rest of your summer, Nick.