1981 Benelli Enduro 125 - Gear oil level?

[Nihil]

Hi everyone,

I'm in the last leg of a Benelli 125 Enduro restoration (1981).
I wasn't able to get my hands on a workshop manual, so I'm not sure how much oil should go in the gearbox..
The side cover (clutch side) has a filler hole on its side.
Am I right to assume oil should be filled to where it will hold no more and start spilling the excess out the fill hole? or will that be too much?

Thanks for your help! I promise I'll post some pics when its done

[R Powell]

The little 6 mm bolt on the side cover is the level for the oil , make sure the bike is upright and not on the side stand. The Benelli motobi club have got a manual for your bike. I had to re jet mine as it would not run on the modern fuel.
good luck

[Nihil]

umm.. I got a little bolt at the bottom of the side cover, my guess its the oil drain,
and a big one at the center of it.
If I fill her up till it pours out the big one the clutch will be half drenched in oil.
Seems right or is it too much oil?

here's a picture:

[R Powell]

umm.. I got a little bolt at the bottom of the side cover, my guess its the oil drain,
and a big one at the center of it.
If I fill her up till it pours out the big one the clutch will be half drenched in oil.
Seems right or is it too much oil?

here's a picture:

Hi that bigger bolt on the side casing is the oil level and the lower bolt is the drain plug. Hope you get it started soon

[Nihil]

Great. thanks for your help!
Hopefully I'll start it this weekend. pics to come

[Nihil]

I had to re jet mine as it would not run on the modern fuel.

Well, I took the bike outside for a test run, and you might be right about the jetting-
The bike started fine when cold with choke pulled and no throttle, but did not rev up easily. had to turn off the choke and open throttle gently or it would bog and die.
Any attempt to move forward while in gear would cause it to bog as well.
Once it warmed up it was near impossible to start, with or without choke (very difficult to find and hold the right throttle position while kicking).
I also noticed a lot of "spooge" splattering out from the exhaust port (missing a seal there), and the spark plug was fouled with oil.

Sounds rich, right?
Lowered the needle to lowest position and it seemed better, but still rich.
Funny thing is I installed a free-flow air filter, so if anything I expected it to be lean, not rich.

I'm gonna try running it with less oil in the pre-mix. I used about 4% oil (1:25) since the motor has been sitting for a while. hopefully 1:50 with synthetic oil will do the trick.

[R Powell]

I had same problem dropped the main jet 3 sizes and bike runs much better the modern fuel needs more air to make it burn. Also check the float height as this can make them run rich.

[Nihil]

Richard, Do you happen to remember the size of the original jet or the replacement?
Took mine out today and its corroded. cant read its size..

Thank you!

[R Powell]

The original jet size is 75 try a lower size to see if it helps, the float height is 23.5 mm. I think mine is on 68 main jet to make it work the new diet 4 star is crap for old bikes!

[Nihil]

Much obliged!
hmm.. my main says "8" on it. not sure if its the only digit (seems that way) or if there were others that corroded.
So a lone "8" would be 80, right?
odd.