Mystery Hole

Wilf · Post by **Wilf** » Thu Oct 15, 2009 9:27 am

Thanks Steve, I will replace the springs and I might as well put a new chain in at the same time.

As far as the 'mystery hole' goes, I'm going to propose a theory after noticing another anomaly in the case. The photo shows where a previous owner had used a hacksaw to cut away an ear that extended up through the upper crankcase cover. My guess is that the carbs were over-flowing so the PO cut away the ear in order to run over-flow tubing through the slot in the cover plate. Then he drilled the mystery hole so that the fuel could drain into the drive chain area. I'm sure the hole is not stock, and there appears to be fuel residue and pitting similar to what you see in old carb bowls. That's my guess.

But now I don't know what the ear was for in the first place. The drawing shows a hole in it, but for what?

Wilf

LOUD MOUSE · Post by **LOUD MOUSE** » Thu Oct 15, 2009 10:17 am

The hole is STOCK and all top cases have it. ...........lm

Wilf wrote:Thanks Steve, I will replace the springs and I might as well put a new chain in at the same time.

As far as the 'mystery hole' goes, I'm going to propose a theory after noticing another anomaly in the case. The photo shows where a previous owner had used a hacksaw to cut away an ear that extended up through the upper crankcase cover. My guess is that the carbs were over-flowing so the PO cut away the ear in order to run over-flow tubing through the slot in the cover plate. Then he drilled the mystery hole so that the fuel could drain into the drive chain area. I'm sure the hole is not stock, and there appears to be fuel residue and pitting similar to what you see in old carb bowls. That's my guess.

But now I don't know what the ear was for in the first place. The drawing shows a hole in it, but for what?

Wilf

FAST FRED · Post by **FAST FRED** » Thu Oct 15, 2009 10:34 am

WILF, THE EAR ONLY HAS A PURPOSE ON THE CA MODELS. IT HOLDS THE CARB COVER ON THAT SIDE. ON CL AND CBs IT HAS NO PURPOSE.

FAST FRED

Wilf · Post by **Wilf** » Thu Oct 15, 2009 10:46 am

Thanks Fred and lm...

I won't worry about the missing ear any more.

So the mystery hole IS stock...what's it for?

Wilf

Wilf · Post by **Wilf** » Fri Oct 16, 2009 9:19 am

LOUD MOUSE wrote:The hole is STOCK and all top cases have it. ...........lm

It must be for the battery vent tube.

Wilf

LOUD MOUSE · Post by **LOUD MOUSE** » Fri Oct 16, 2009 10:43 am

I don't have a clue.
Nowhere is it mentioned in the HONDA data. ......lm

Wilf wrote:Thanks Fred and lm...

I won't worry about the missing ear any more.

So the mystery hole IS stock...what's it for?

Wilf

LOUD MOUSE · Post by **LOUD MOUSE** » Fri Oct 16, 2009 10:45 am

Would ya vent battery acid/vapor on the side of the engine and chain?. ..........lm

Wilf wrote:
LOUD MOUSE wrote:The hole is STOCK and all top cases have it. ...........lm

It must be for the battery vent tube.

Wilf

Honda305.com Forum

Mystery Hole

EAR HOLE