DIY - Replacing Amp Meter on Royal Enfield Electra 5s

Amp meter is mostly found on Iron Barrel (/Cast Iron) models of Royal Enfield. As the name says it shows the electric current flow/consumption in the motorcycle (wiring). 

Royal Enfield Amp Meter Grey, for Electra 5s

Now in the real world, the following are some of the use of the Amp meter, which I am aware of:

1. When the engine is running, it should lean towards the + sign (this means the battery is getting charged)
2. When any accessory (e.g. blinkers, headlight, horn, fog lamps, etc) is switched on, the meter needle dips towards the - sign, indicating power being consumed. Higher displacement of the needle to the left means more power is being drawn by that electronic accessory.
3. While kick-starting, if the needle dips towards the - sign, mean there is compression in the cylinder (first decompress the engine using the lever and give a half kick, and then try to start as usual)
4. [Update] If battery terminals are wrongly connected (reversed), the needle may dip to the -ve sign (This is just for info, plz do not try this one!)

Now am not sure if there is any other use for this thing. Feel free to leave a comment on this post if you know of any other use. So coming to my bike, it runs with an HID as the main light source and a set of halogens (55w x 2) for fog/rain, and on long tours, the phone (/gps) is wired to the charging port all the time. So I just keep an eye on the charging of the battery part, and hence have to rely on the amp meter from time to time. And of course, while kick-starting in the mornings. Anyway, now the amp meter on my bike had conked out a while ago and I had to get it replaced. Today I got some time to get my hands dirty. I had purchased a spare one for my Electra, so I just had to unplug the old one and put the new one in place. Yeah, its that easy, provided you have tool-friendly hands (meaning you know how to use tools without being all over the place and making dents and scratches on the bike).

Here are the steps to follow to get this job done.

Unplugging the old Amp meter from the main harness:

1. Ensure that your ignition is off and possibly take the key out for now
2. Get a feel of the set of cables, which is popping out from, below the amp meter, and see where its plugged into the motorcycle's wiring harness
3. If you can freely reach that plug from the side of the doom, then just try to unplug it (/detach) from the main harness by releasing the tiny plastic lock on one side
4. If you are not able to reach that connection/plug from the side of the doom, remove the doom from the head (do it carefully and keep it aside on the floor or on a cloth to avoid damaging it) and complete step 3

The female plug, is part of the motorcycle's wiring harness (notice the locking mechanism on the right side of the plug)

I had to open the headlight doom to reach the amp meter cable

Now the amp meter set is unplugged from the main harness, it is time to pull out the meter console from the head.

Removing the old Amp meter console:

1. Get a screwdriver and a piece of cloth (the one you keep for wiping your bike is also fine)
2. Now put the cloth on the handlebar, using it as a fulcrum, and with the flathead of the screwdriver try to slightly pry out the amp meter's ring from the head (do this slowly) 
3. Do the same thing from the front side as well and with each attempt try to lift the meter by half an mm and avoid being too hard on it
4. After a couple of attempts from front and back you should be able to pop out the meter (and maybe with the rubber sleeve around it out of the socket

Now as the old one is out, now the task is to fit the new meter in.

Fitting the new Amp meter console:

1. Put the new rubber sleeve into the slot, until it fits flush (as you can see in the images below)
2. Slowly put the cables inside the hole and work your way with the meter to sit in the slot perfectly
3. Slowly push the meter down until it fits in the slot and only the rim of the new rubber sleeve is visible below the metal edge of the meter
4. Now carefully take the meter cable route it around the speedo cable and plug it into the motorcycle's wiring harness ensuring that the plastic locking mechanism has slotted in properly
5. Move the handle from side to side and check the cable you just routed should not be getting pulled/stressed at any position of the handlebars

New amp meter without the rubber sleeve

First, put the new rubber sleeve in, then carefully slide in the amp meter cable followed by the meter console

Time to test the new setup before calling this DIY complete.

Testing the new Amp meter:

1. Put the ignition key in and switch it on
2. Switch on the blinkers and see if the needle flicks toward the -ve sign
3. Repeat step 2 for horns, headlights, fog lights, and any other accessories you wish to see the power consumption for
4. Now power up the bike using kick/self-start and see when it's idle, if the needle is leaning towards the + sign

That's it, the meter seems to be working fine. If you had to open the doom for this job, now you can fix it back.

 Amp meter needle in a neutral position : the ignition key is turned on, but the engine is not running

The engine is running and with a slight twist of the throttle the needle is going towards the + sign (in idle it still goes towards the + sign, albeit very less to capture in a photo)

Hope this DIY comes in handy when you are in need. For queries/suggestions, leave a comment below.

Cheers !!

Sid