has anyone tried a go kart carburetor on a puch maxi?, something like the ibea L6
Don’t know about that particular brand but I know people have used diaphragm carbs before.
Diaphragm carbs are nice...they have there uses
> todd amundson Wrote:
> They rule
Iv seen a few pukes in my day & I have to say that bike is perfectly simple! Wow it’s perfect 😭 it’s reminds me of the good old days when mopeds were simple
Don’t touch it!
I've used a 24mm Tillotson but not the Ibea. Interesting stuff. Make sure you use a fuel filter.
I had asked about using a tillotson on a moped a while back and got a lot of poo poo answers about it working. I'm glad that they do work.
Where is the bonus of them, where do they fall short?
Have to have a pulse line
On piston ports the pulse hole just needs to be exposed in the intake. I think with reeds the pulse line has to be behind the reeds?
From all the threads I’ve seen seems like they just aren’t as tuneable as other carbs. People were saying it’s more of an “on off” switch that you couldn’t really tune it to run half throttle. So sounds good to me for a variated bike. Your usually full throttle then coast on them
I have one on a v1 polini and all I needed to do was notch the intake to meet the vacuum circuit and it works well. If you run the carb "upside down" with the diaphragm on top you can also use gravity to your advantage. It takes a little playing around with pop off spring to get the mid range dialed in, but yeah it's basically an on off switch. Super fun though.
Also a tillotson hl-166b will very nearly bolt right up to a vm20 intake.
I'm not concerned with an "on/off" switch situation. My bike has the motion pro throttle and there is hardly anything but WOT on it. It has like maybe 45° of rotation, so even my vm18 is kind of on or off.
Do they work better with reed setups or piston port?
The on off switch thing is because the pop off pressure isn’t set right. Basically it will run out of fuel or flood if the case pressure rises or drops below the pressure in the vacuum diaphragm making it want to die off of idle and really really hard to start. (edited)
> Daniel '' Wrote:
> The on off switch thing is because the pop off pressure isn’t set right.
> Basically it will run out of fuel or flood if the case pressure rises or
> drops below the pressure in the vacuum diaphragm making it want to die
> off of idle and really really hard to start.
This sounds correct. Pop off tester is in my tool box. They start and run great if you get it between 9-12 inch lbs. is it inch pounds? Think it is. https://mopedarmy.com/forums/read.php?1,4094781,4095260,flat=1#msg-4095260
Yeah 9psi worked for a polini, though we only tried it with the one spring it came with. It was a bitch to start and didn’t have much in the way of quarter throttle. It wasn’t my bike so I never really took a crack at tuning it, but I think I understand the concepts. I wonder if a using a vacuum gauge on the pulse feed intake manifold would help with tuning of pop off pressure. I the think most tilly and walbro carbs have spring kits where they come with a few springs and some shims.
Todd you are the MAN
Anything else you want to share I'm all ears, what models work well, what you've used them on, etc.
So they would work best as a case induction carb?
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