Rooster tail carbs

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There’s too much snake oil out there. I need real world experiences like in my other carb thread. If I believed the first thing I’d heard, Tillotson are supposed to be the best but the experienced people on here that have used them say otherwise.

If they were that good then everyone would have them.

I’m just looking to eek out every last drop from what I have.
 
Does it make a noticeable difference though?

Cheers Sean.
Idk I don't have one. I've had a few short and cryptic conversations with the owner about how he modifies them, and got the above response from him. Internal modifications for more fuel flow (lowered pop pressure, is my assumption here) and the venturi was confirmed to be bored out.
Several of the guys have them and seem to like them.
 
Idk I don't have one. I've had a few short and cryptic conversations with the owner about how he modifies them, and got the above response from him. Internal modifications for more fuel flow (lowered pop pressure, is my assumption here) and the venturi was confirmed to be bored out.
Several of the guys have them and seem to like them.
Nice one mate, that’s good to know.

I might look at getting one.
 
Sounds like just another wallet bait gimmick for the average RC enthusiast. I want to share a quick story. Back in the late 80's when I started racing motocross it was all about who had the most expensive bolt on go-fast goodies should end up on the podium at the end of the race. Pro Circut pipes , race ported cylinders , rifle bored carbs, V-Force reed kits and so on. This was usually not the case. I remember one specific race I lined up next to a guy who had a TON of expensive hop-ups into his bike this guy was so amped up bragging about his mods and ready to kick the shizz out of the rest of the rider field. Long story short I smoked this guy right from the drop of the gate. Why ? (I really wasn't any more skilled than him) , but because when I was checking out his way fast ride before the race I noticed a half worn out rear tire. (My way slow mostly stock ride was in TOP mechanical tune and "race ready" with an almost new rear tire. So I think you will be able to figure out the moral of this story, and just something to think about.
 
I get it totally and that’s what I want avoid. I’m careful about what I do but still make mistakes that’s why I rely on you lot for advice.

Thanks Polar.??
I know what I know, I know what I don’t know and I don’t know what I don't know.
 
Without bashing the guy too terribly much, this is the simplest reason why I wouldt buy one. Hes extremely arrogant. His go to in our conversation was "I'm a fuel injection specialist, I know what I'm doing." I made it plainly clear, that I was not looking for trade secrets and more or less for hin to confirm my assumptions, I got the run around on everything but them boring the carbs out and using a larger butterfly. Beyond that I was talked to like an idiot. I know I'm not the smartest person out there, but I'm not a fan of being talked down to either. Having said that a lot of guys like them, even rc max offers them on a few of their engines as the carb of choice. So really they have to work well for them (rc max) to place them on a highly liked engine. To me there are plenty of carbs in the sea that don't need modified to satiate the fuel and air needs of a 2 stroke, the issue is finding one that meets your specs. I haven't had the time or a reliable way to quantify data or I'd toss about every version of walbro and zama I have at some if these engines to see how they react. Also from what I've seen the r carbs take a std rebuild kit, and theres only so much that can be done with them fuel wise, without making them sensitive to needle adjustments. Carbs are simple animals there really isnt a lot complicates going on in there.
 
On a standard one no, the venturing is larger on a 1107.

You'll see the biggest improvement with a rt990 with a reed engine or something that could use it.
 
On a standard one no, the venturing is larger on a 1107.

You'll see the biggest improvement with a rt990 with a reed engine or something that could use it.
I’m using ported pistons mainly and have standard 1107s so I’ll stick with those then, well I mean I’ll try a RT1107.
Cheers John.
 
Without bashing the guy too terribly much, this is the simplest reason why I wouldt buy one. Hes extremely arrogant. His go to in our conversation was "I'm a fuel injection specialist, I know what I'm doing." I made it plainly clear, that I was not looking for trade secrets and more or less for hin to confirm my assumptions, I got the run around on everything but them boring the carbs out and using a larger butterfly. Beyond that I was talked to like an idiot. I know I'm not the smartest person out there, but I'm not a fan of being talked down to either. Having said that a lot of guys like them, even rc max offers them on a few of their engines as the carb of choice. So really they have to work well for them (rc max) to place them on a highly liked engine. To me there are plenty of carbs in the sea that don't need modified to satiate the fuel and air needs of a 2 stroke, the issue is finding one that meets your specs. I haven't had the time or a reliable way to quantify data or I'd toss about every version of walbro and zama I have at some if these engines to see how they react. Also from what I've seen the r carbs take a std rebuild kit, and theres only so much that can be done with them fuel wise, without making them sensitive to needle adjustments. Carbs are simple animals there really isnt a lot complicates going on in there.
I’ll to talk to my engine builder and see what he says, he has a proven dyno but can also be a bit vague.

He knows I’m a basher and I get the impression he doesn’t like that as he is clearly into pro-racing with Elcons and MCDs.

I hate arrogance there is no need for it. None of us were born knowing it all and had learn somewhere, either with advice, learning or personal experience through trial and error.

WTF is wrong with people.
 
On a standard one no, the venturing is larger on a 1107.

You'll see the biggest improvement with a rt990 with a reed engine or something that could use it.
This right here is THE critical comment. A combustion engine is simply an air pump. No matter what you bolt on and mod the single fundamental concept is "The more air you let IN, the more air needs to be let OUT. If your engine won't handle the added flow, all's your doing is probably loosing hp instead of gaining.
 
This right here is THE critical comment. A combustion engine is simply an air pump. No matter what you bolt on and mod the single fundamental concept is "The more air you let IN, the more air needs to be let OUT. If your engine won't handle the added flow, all's your doing is probably loosing hp instead of gaining.
The ratio is also important you can‘t just add more air as you’ll lean the mixture out too much. More air needs more fuel, that’s the case for any IC engine.
Details aside I just want to know what’s best.?

I’m guessing that I’ll have to travel that road alone as everyone has different setups and run in different conditions.
 
What's the improvement? Throttle response, speed increase, easier tuning?

All around, I mean its not an OMG difference but I noticed increase in throttle response, it seemed faster also but I don't run a gps to verify. There are a few videos of someone comparing them and the speed is greater.
 
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