Day 3

Accomplished 3 things tonight:

1. Checked on Tank de-rusting progress
2. Got measurements (and found!) a new battery
3. Removed huge rear mudflap and installed plate

 

Tank Cleaning

Tank has been filled with vinegar for 1 week. I was curious and poured some out to see how the progress is going - and the tank is already spotless inside! Vinegar worked!

Some vinegar poured out, inside of tank is spotless 

Inside tank, limit of the vinegar (brown liquid in lower half), the inside tank (upper part) looks great.

Next I will remove all the vinegar, neutralize with baking soda, rinse a few times with gas + 2-stroke oil mix (to both coat the inside of the tank so it doesn't rust, and also to remove any remaining water), get the petcock back on, and fill it up with gas. 

Battery

After a week of searching online and a visit to the local moto shop, I finally found the modern equivelant to the most random obscure battery on the planet. 

Original reference

YB7BL-A

New reference 

12n7a-3a - X4

And I found a shop in France that actually carries it!

The new battery is the closest thing I could find that has same characteristics AND dimensions. 12 volts, 7 amp, and that fits in this tiny, skinny little battery holder on the bike. The more common 12na7a-3a is slightly too wide (at 75mm). However I found a shop that carries a few versions of the same battery that has the exact dimensions I need and also the gas exhaust port and polarity on the correct side. 

Interesting things I've learned about lead-acid motorcycle batteries. 

• Volts and Amps differ a lot, once you find what you need then even for the same battery:
• Dimensions (usually two of the three are perfect, and the third side is too big)
• Terminal location (positive and negative can be on either side / orientation)
• Gas / exhaust port location. Since these batteries breathe, there is a gas escape port

So I finally found the battery that meets all the criteria and will fit in this tiny cage:

Battery cage, constrained to 153mm L, 135mm H, 68mm W

Backside

Cleaned up the rear a bit. Took off this huge tractor mudflap (don't plan on riding this thing through the forest).

Dump trunks don't have flaps this big!

To my surprise, there was a nice bracket already installed so putting on the plate (from my CBR) was a breeze.

Looks better with a plate. Now we have to get it to run.