Finally got around to sorting out the cracked clocks that my 749R came with. Bought a set of second hand clocks off ebay in Italy and carefully took both of them apart and swapped the internals. I now have a set with both mode buttons and no cracked screens! Yay! BUT..... When I took the original internals out of the cracked cases, something was rattling around INSIDE the circuit boards. Carefully undid them and this little baby fell out! WTF? The clocks appear to work fine, all lights etc, modes, bike starts and runs. Well weird. Any ideas?
Looks like a Ceramic capacitor Richard, probably rattled out due to dry joints. I wouldn't worry too much, the clocks might explode at speed and take one or both of your eyes out- italian electrics eh.
From the back of the circuit board. Capacitor. Some are blue but in this picture red https://goo.gl/images/YJfDt1
Very useful John! Of course, you’d know all about dry joints, what with your electrician background an’ all.
Its function is to store the electrical energy and give this energy again to the circuit when necessary. In other words, it charges and discharges the electric charge stored in it. Besides this, the functions of a capacitor are as follows: It blocks the flow of DC and permits the flow of AC.
so look on the bright side then, they might last a couple of hours or even a day or two before they go pop.
Assuming the ' Unidexter's' capacitor can be identified and a replacement found, I would be happy to resolder to your board if it's still accessible? We should be able to see where the little blighter has escaped from as one of its legs will still be protruding, and nearby will be a tiny hole where it's other leg lives. I have a tiny instrument soldering iron and steady hands!
@CRYSTALJOHN that is a very generous offer! We can arrange a meet up so I can observe your tiny instrument and steady hands.
It's actually a varistor (a variable resistor), not a capacitor, which is used for over-voltage protection to a circuit. That is an EPCOS varistor (identified by the older UR logo) series 14 (S14/K14) means it's 14V protection, which makes sense. The EPCOS part number is B72214S0140K101 Vrms = 14v Vdc = 18v iMax (8/20uS) = 1000A Wmax (2ms) = 4 Joules Pmax = 0.10 Watt You should be able to find a direct replacement or equivalent for a couple of quid. EPCOS spec sheet: https://www.digchip.com/datasheets/download_datasheet.php?id=5397692&part-number=S14K14
My hands are not so steady atm. Just come back from a ride in the jungle which I had to abandon as the track was too rough and I was getting exhausted. mostly learnt some tough lessons when I’ve got the bike stuck and put myself in danger, so I thought it would be best to head home. I’m always worried about snakes, as where I am has 3 of the deadliest snakes in the world: The king Cobra ( with which I’ve had a close encounter), The Russell’s Viper, and the Krait. Nearly out of the jungle and back on the road when I nearly rode into a 4’ long silvery slithery snake , I had a panic reaction when I saw it and grabbed the front brake which locked the wheel on the dirt track and nearly had me off ffs! I’m still a bit shaken, as I’m a bit phobic about snakes, me hands are a bit shaky. I’m back in a couple of weeks, be glad to show you my tiny instrument then.
Clocks now mended. Massive thanks to @antonye for identifying the part number of the thingamy-whatsit - bought 5 of them from RS for less than a fiver. Massive thanks also to @CRYSTALJOHN for coming over yesterday with his soldering kit and years of experience to solder the thingamy-whatsit back onto the clocks. Points of note: Removing the Rev counter needle is a bit tricky - requires a fair amount of force to be carefully applied under it without damaging the face of the Rev counter. It’s easy to turn the spindle while doing this so it is important to note where the “zero” point is. I found this out when the job was done and I’d put the clocks back in the cases and back on the bike. I thought I had been sufficiently careful to make sure it was installed back at “zero”....no, not quite. When the ignition was turned on, the needle did its sweep around the dial but when it parked, it was registering below zero. Took it apart again...removed needle, lightly installed it on the shaft, carefully plugged the unit back in without cases fitted and switched it on. When it parked I could remove the needle again and install it back at Zero. Anyway...lesson learned and passed on. Update. Clocks
