APT SmartCarb
 

First of all, I am not affiliated with APT, I just found this to be quite intriguing. I saw this carb mentioned on DirtBike Magazine's website in the news section and thought I might've seen Clay mention it here on the forum in the past. Does anyone know anything more about this? http://www.powerapt.com/smartcarb.php
btw, I find it very impressive how involved Clay is on this forum.

Let's say it improves fuel economy by 30% - just an optimistic guess as they don't list any hard numbers. So my 300 that gets around 23 mpg goes to 30 mpg. Riding 2000 miles per year (I don't ride nearly that much BTW) I'd save $80 a year at $4 per gallon. At $775 for the carb that's a lousy payback.
FWIW, my Honda 250 gets 30-35 mpg with its inferior EFI.

Its an interesting concept, quite possibly superior as they claim, but the price is just stupid. Not too many bought for tinkering with I'll bet.

The greater efficiency is great but I am far more interested in their claim that it autocompensates for altitude changes. Where I live I can go on rides that will see 5000' of altitude changes. I do think that it is safe to assume that there's not much first hand experience w/ this product b/c of the price. You'd think that they'd enter the market with a lower price to see if their product would take off.

I bought one. I will post a review soon.
It is everything they say it is.

Bike sounds raspier and even the exhaust smells different due to the complete combustion of the fuel mixture.

Awesome. Did you buy a straight bore or a taper bore? Let us know how well it auto adjusts as well as the increase in efficiency. I look forward to it.

Is it a variable venturi like the Predator?

It is a straight bore.

No variable venturi.
It has a conventional slide with a straight needle.

You adjust the mixture by moving the needle up and down. That is done by the knob on top of the carb. You hold the throttle wide open ( engine off). Then push down on the knob to engage the needle and make the adjustment.

And that's it? Are there no further adjustments due to temp or elevation change?

I would love to try one but $800 for a carb! That's some carb!!!