Honda Spree and Elite 50 Forums

When doing the air pressure test as per the Honda Shop Manual ... should it be air tight or what is an acceptable leak when doing the pressure test?

True, there is not a leak down spec. The air valve is a sliding fit with no sealing seat or rings, so it's going to leak.

In my opinion:

• Slight leak of the air valve from input to output (bypassing the carb slide) will not have much impact on idle speed or mixture. If the air bleed screw gets turned in much further than the service manual, then look for air leaks - wherever they may be.
• The fuel side is not impacted by minor air valve leakage. Leakage between the engine side and bystarter causes slight airflow. But the air bleed holes in the fuel pickup tube break suction until air flow is greater.

Thank you. In order not to pollute this subject, I'll give feedback on my subject.

-- Emulsion tube visual identification --

Note: Only the Elite Unrestricted tube is shown. It has two sets of holes at 90 degrees. Pic shows both views Note: Aero has two sets of holes at 90 degrees. Pic shows both views Note: Sporee has two sets of holes at 90 degrees. Pic shows both views Note: Gyro has only one set of holes

mousewheels wrote:-- Emulsion tube visual identification --

Emusion_Tube_Aero_NB50_A.jpg

The emulsion tube with the most holes is the unrestricted one, yes?
The part number indicated is the restricted or unrestricted part number?

Thanks.

PS : did you get to use the video I had made for the leak test on the by-starter?

saved,

The emulsion tube with the most holes is the unrestricted one, yes?
The part number indicated is the restricted or unrestricted part number?

Thanks - I've updated the posting to clarify. I have only a un-restricted emulsion tube and its got two sets of holes.

PS : did you get to use the video I had made for the leak test on the by-starter?

Can you point me to the video again? I will add to the wiki. Thanks!

Greetings:

Mouse is the Master. Can you re-size my giant pics in Fab Flash thread? Or better still, tell me how?

mousewheels wrote:

The emulsion tube with the most holes is the unrestricted one, yes?
The part number indicated is the restricted or unrestricted part number?

Thanks - I've updated the posting to clarify. I have only a un-restricted emulsion tube and its got two sets of holes.

PS : did you get to use the video I had made for the leak test on the by-starter?

Can you point me to the video again? I will add to the wiki. Thanks!

At the end of this post, you have the video : http://www.hondaspree.net/phpBB3/viewto ... 20#p251818

Do you think there is a big change between a restricted and an unrestricted emulsion tube?
I have a restricted Aero. It has been derestricted by the ramp plate and the washer in the pipe.
I have not changed anything with the carb though.
Was wondering...

Do you think there is a big change between a restricted and an unrestricted emulsion tube?

Sorry - still something I'd also like to know. I have not yet had a emulsion tube from a carb with the id tag from a restricted scooter to compare.

Pilot Jet orifice measurement (approximate)
Using a set of pin gauges (seller says accurate to "-0.0002")
I found anything up to 0.013" would pass through, and the 0.014" would not

0.013" is about .33mm, The 'nogo pin' at 0.014" is about 0.356mm
The 0.013" pin is has some wiggle room, so 34-35 is a reasonable figure for the Spree pilot.
Pilot Jet size - from other Honda Scooters
The Honda Elite 1987 SE50 manual documents the 'Slow jet' size as a 35
The Honda Elite 1988-2000 SA50 manual also documents the 'Slow jet' size as a 35
Pilot Jet - aftermarket replacement
eBay seller 'chopchop*123' is selling Spree pilot jets in what he says is the stock size '34'.

Previously he had some oversized pilot jets for the Spree also - to go with his big bore kits.

Ed: I reposted this from local files as it was in the wiki and not accessible until recently. perhaps this should be deleted? 03/17/2021

b]Pilot Jet - Orifice Open Verification by Light[/b]
One method mentioned on this board for verifying the pilot is at least 'not plugged' is by light.
Note: Start with an expectation the test requires a bright light and that the pinhole of light remains dim.

Here's a pic of the carb showing a clear Main Jet and no visible light through the pilot jet - even though the pilot jet is clean/clear.
The reason the pilot jet is so dim relative to the Main Jet, is the light path is indirect.
The carb body idle mixture passage is offset from the pilot jet orifice
Light from the carb slide side, must bounce off the pilot jet then bounce off the carb body.

Photo setup to verify idle jet
Indoors, I use a bright flashlight, to view the pilot passage, and it's still relatively dim.
Using a camera can help make the light visible, note the camera setting of 1/6s, ISO400.

Hello all, I have inherited a 1986 Honda Aero 50 that was sitting for a long time and would not even turn over when I got it. Since than, I have been able to start by spaying starting fluid in the intake but it will only run for a few seconds. A little history on the issues. Oil was leaking into the crank causing the piston to not move when cranked and that has been cleaned out. Now it tries to start but won't so i changed the spark plug, carb, battery, fuel lines, and I cleaned out the fuel tank. Checked piston compression, good there. Checked petcock to see if operational, good there. I read a thread that said the exhaust could be the problem so I took that off and same issue. Another thread said, these won't stay running unless if the air filter and box were on so I put that back on with a new filter and same issue. I am stuck and don't know where to look. It's almost like something is telling the motor to turn off. Any ideas? Thanks in advance!

Carb Mixture Screw and Idle Screws
Mixture screws in general seem to be no longer available
Idle Speed screws can be found

Most carbs adjustment screws interchange with other models.

Carb models with O-Rings or washers on the adjustment screws
In creating the table in the last post, it was noticed only 3 models had o-rings on the mixture screw

Note the p/n between Item 5 'mixture screw' is same between 88-93 SA50 vs 94-01 SA50. The parts fiche may have omitted the washer.
The 94-01 SA50 added an o-ring to the idle speed screw.