Starting after top-end rebuild and new carb

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loadedscooterist
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Hi All, So after fitting a new top end and various other new bits I finally have an assembled engine.

My top end consists of a budget 185 kit - 22mm Dellorto and I have a AF 42MM Clubman.

So go to start and it starts first kick and sounds much better - however, it then cut out after running for about 45 seconds to a minute and then refuses to start again. So I cleaned out the carb and it then restarted but again only for a short time.

So in terms of jetting here is what I have:
Setup:
Atomiser = 7895-2 (I do have a 7895-1 spare)
Main Jet = 118
Pilot Jet = 50
Starter Jet = 50

So now looking for some advice as to setup of this carb (or anything else I may have overlooked).

Thanks in advance
loadedscooterist
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Sorry instead of Atomiser please read Slide!
rosscla
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I'd have said your pilot and main are too big for that set up.

My Lince standard 200 is running a genuine SH2/22 and clubman currently on 45 pilot and 112 main and still looks nicely rich.

I found starting really bad with 50/118 and running really lumpy. I worked down one main / pilot at a time till it started and ran better. Despite what people will tell you I found the main had an impact on starting more so than the pilot.

Just my observation.

What atomiser is it by the way?
"Our dilemma is that we hate change and love it at the same time; what we really want is for things to remain the same but get better."
Daggs
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Your Main jet is irrelevant. You need to be looking at the pilot circuit.
eg. Choke, Pilot jet, air-screw.

My best guess is you are running too rich at the pilot circuit. This will help it start from stone cold, but as soon as the barrel warms slightly will cause flooding.
If you can repeat what happened before? Take a look at the plug it'll be soaked.
If so, drop to a 45 pilot and try again.
rosscla
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This is why I said it. I knew someone would disagree. ;-)

There is no way for the fuel to reach the pilot jet other than through either the choke jet or the main. The pilot is not drilled through into the float bowl. I found that it had an impact in mine.

I do agree that dropping the pilot to 45 would be the first step but also be prepared to test dropping the main to see if it makes a difference in your set up.
"Our dilemma is that we hate change and love it at the same time; what we really want is for things to remain the same but get better."
loadedscooterist
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Location: Falkirk
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Hi All, Thanks for the updates! As I have been finding my way through this whole process with this scooter any help is much appreciated for me.

I only posted as much info as I could as I thought someone would ask me what x was.

I will need to go and buy a 45 as I dont have one. I agree that its better to change one thing at a time so thats going to be my starter for ten.

Once I have that I will post findings as I am sure someone will find it useful

Cheers and have a great weekend!
rosscla
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Get a 45 and a 48 and a selection of mains down to about 110

It'll save you on postage in the long run.

Try Scootopia or Scooter Restorations
"Our dilemma is that we hate change and love it at the same time; what we really want is for things to remain the same but get better."
loadedscooterist
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Hello all, back again. I have now had some time to look into this and bought a few spare jets and played around with it. So current set-up is

Pilot : 45 (also tried on a 48 but that started even worse)
Atom Jet - 5699-1 (that's what it looks like anyway by the small writing on it)
Main - 112 (The colour of the plug is a nice light brown though).
Starter Jet - 50
Air-screw - 1 and 1/2 turns

I have a good fuel flow and a spark as well. I did change the plug to a new one as well. This is a new Scootopia 22mm carb BTW and also has a casa air filter and bellows installed.

My main issue is that it's still a struggle to start (maybe 20 kicks from cold?) e.g it sort starts but then dies quickly after. Once running its been fine so think my main jet sizing is good as the plug colour is a nice light brown but the start-up procedure is the thing thats getting to me!

So looking for further advice on getting this to start within a couple of kicks as it should.

Cheers!
nick b
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we have this attitude bigger is better but I run a rt 195 on a 118 jet and 3rd clip it starts on half a kick everytime and flies In my opinion it is a balancing act that maybe a 125 jet on 2nd clip would work equally as well I have a pwk 28 but iam sure this applies to most carbs
loadedscooterist
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Hi Nick, Thanks for chipping in. I am sorry but don't understand what you mean by 3rd Clip. My carb is a 22mm Dell Orto and the main jet has no bearing on startup.
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