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[Simplo]

Nothing to do..
No air leaks...
I'm really getting mad...
Today I wanted to try to reset the float...
A few days ago I also cheked it.
First of all I didn't found any reference about the setting; the pdf at this link: http://www.hitchcocksmotorcycles.com/pi ... s_-_a4.pdf
refers to a little different model of carb. Mine does not have the choke leverage, but just a rubber tap, so I'm not sure the setting is the same.
But...
It says:
"With the carb held upside down and the float chamber gasket removed measure from the carb body surface to the
top of the float, as shown below. The standard measurement is between 24-26mm (see picture)."
It doesn't says if this setting is for both 24 and 26mm carbs.
Also, I don't understand if the position of the float is to consider just when it touches the plunger or when it really press on it (because of the spring).
Anyway I checked it considering the first case. On my carb it was set at 21mm so I changed it at 25mm.
All other settings are standard: air screw at 1 and 1/2 from closed and needle clip at 3rd groove (as it always has been for 10 years).
Result was: the engine starts at first kick with choke. The RPM increase using the throttle with choke on. The engine runs at regular idle also without choke. The engine drowns as soon as I use the throttle, without choke.
Today I tried to reset the float at the (orginal?) 21mm.
All other settings to standard.
The engine did non started with choke, but it started without choke at first kick.
RPM increased (without chocke) but with many coughs.
I played a lot with the air screw and after a few minutes the engine seemed to be ok with standard 1 and 1/2 turns from closed!!
So I turned off the bike and refitted al the temporary mounted parts.
Then I tried again: the engine does not starts with choke, but only without. And... nothing to do again! It runs at idle, but as soon as I use the throttle it drows, even if I let it warm.
As soon as I open the choke it turns off.
The only thing I can thing is that the float is not working well but I checked it: no holes, smooth movements....
Is there a way to check the fuel level in the float bowl? My carb has not inspecting screws...

[Gwilly]

I think you've just proved the float is working buy the different results in starting, in relation to float height and choke use..

The float height is the same for both VM24 and VM28 so i would take the float back to 25mm where it starts on the choke..

Leave the air screw at 1.5 turns out as you've proved a tickover..

Examine the new needle you've fitted and check it has the same taper and numbering as the old one that you bent..

if it is the same then lower the clip to the bottom groove and reassemble paying particular attention to the throttle cable adjustment on top of the carb, take up slack in the outer cable but not too much, its important that you can hear the slide click or clunk when you release the throttle and the slide closes.

Try not to have any tight bends in the cable and ensure that the slide still shuts with a clunk with the handlebars turned full lock left and right..

Its easier done than it is to explain.. Basically with the float at 21mm you don't need the choke as its already too rich, too much fuel in the bowl..

[Gwilly]

A line seems to have disappeared in posting..

Measure the float height with the float gently resting on the float pin, (carb upside down)

Do not apply any finger pressure on the float, Just gravity only..

[Simplo]

Hi Gwilly,
I'm start to be persuaded that is afloat issue.
Last time I tried (I can't remember what exact settings) I closed the tank fuel tap while the engine was idling.
After some time it started running nice and responding to throttle as it should.
After another 10 or 20 seconds it became poor and turned off.
I reopened the tap, restarted and it didn't run weel, turning off as I actted to the throttle.
Then I closed the tap once again ad after some time it returned to run well.
So I think, now, the level is to high and when I close the tap and the fuel level reduces, it reaches the ideal level and the engine runs fine.
So I think I will ignore level indications (mikuni says 16mm, Hitchcock's pdf 24) and will procede with trial and error...
Thank you all!!

[Creaky45]

Short reply:Condensor (Capacitor)
Long reply:
Just read your post right through again and I have a thought. My Bullet, same as yours came home on a tow truck the other day because of a similar problem. It was running fine and then suddenly started missing and eventually stopped. I checked all the obvious things like you have and the strange thing was it would start and idle perfectly but any amount of throttle or load and it would splutter and backfire and that's why I called a tow-truck. When I got it home I disconnected the wire to the distributor and connected an ohmmeter between it and earth to check the points and got a short circuit (normal) with them closed but with them open I still had a partial short circuit and the only thing to cause that could be the condenser. Sure enough that was the trouble. Test yours with an ohmmeter and compare the test with a good one. If you don't have an ohmmeter just try a replacement. If you don't have one, any old bike or car condenser will do and it does not have to go inside the cover. Just connect it between the wire and earth. Mine was definitely faulty and I still don't know why it started and idled so well.It runs perfect now. Just a thought but easy to check. Please let us all know how you are going.

[PeteF]

The float test in your last post COULD mean the float is too high BUT.
It could also mean that the carb too rich and, as the level of fuel in the chamber drops, the mixture is going leaner.

[Simplo]

Hi Creaky45, thanks for you idea. I also tought that it could be an electric problem, but with choke on the engine runs as ot should, at any RPM, so I don't think it can be a condenser issue. But your sytem to check it is very useful!

[Simplo]

Last news: as I wrote in the last post, it seemed ot was a float problem. Current settings are: float:21mm, needle at the bottom place (richest mixture), air screw at 1 and 1/2 turns from closed.
The engine starts at first attempt with the choke, throttle is ok with choke, it idles right without choke, it turns off with throttle, without choke. Closing the tank tap, after a few seconds, the engine runs well.
This morning I removed the carb and just changed the needle position up +1, no other settings changes.
After starting the engine and let it warm it runs right. I turned it off and let it get cold, then restarted after 20 minutes: ok.
I'm not really persuaded the problem is fixed, tomorrow I will try again.
If all will work, my idea of all this story is:
- first problem was due to a float problem because of a long time without using the bike
- then I disassembled it and blended the needle. Maybe also I altered the float setting.
- I replaced the needle, but with the wrong float setting it didn't worked right
- Than I started to alter the float, the needle and the air screw without catching the right set, just because it seems my specific carburator, engine and PAV are different than any setting document I found.
The only mystery I can't understand is why after I replaced the needle, on the very first run, the engine was running good...
Next days I will tell you if the problem is fixed and write also the final settings, hoping they can help someone!
Thank you all for your very appreciated patience and support!!
You are great!

[papasmurf]

Simplo, if you weren't mad before you bought a Royal Enfield it won't be long before you are.

[Simplo]

papasmurf: eheheheh you are right.
Here is a stupid video I made many years ago with another italian Royal Enfielder...
https://www.dropbox.com/s/m351ipzib667d ... F.mpg?dl=0
Sorry, no english version so subtitles are here:

Slide 1
The Royal Enfield temptation cause in his victim's mind a storm of doubts...
Slide 2
"Will I have to adopt a -vintage- look?"
Slide 3
"Will I find a mechanic who knows it?
Slide 4
"Will it be so hard to find parts?"
Slide 5
"Will it stop in the wrost circumstances?"
Slide 6
"It is an indian bike, does it uses strange oriental technologies?"
Slide 7
"Will I be too slow?"
Slide 8
"Will the right gear be a problem?"
"Down! Down! Third gera is down!!"
Slide 9
"Than you find one"
Slide 10
"New or used"
Slide 11
"And they turn it on"
Slide 12
"Welcome"

PS: forgive my bad translation