HEY EARL???

[Forzfed]

Got some Toomey pipes for my 2 smoker.  The bike has power jet carbs.  Is this a good thing or bad?  I thought they gave better mid range and you could run a smaller main jet and the power jet would compensate for it at WOT.  What is your take?

[earlbrown]

No idea. I've never ran them. I looked that the FAQ and it looks like gimmiky horseshit to me. According to them the valve only helps tune the top end and effects nothing else...   Your discription sounds more like an automotive power valve (IE enrichment circuit).
That's not how bike carbs work. Plus who cars if you can run a smaller main? I've never hard of bench racing with main jet size much less wanting a small one! Top end fueling is a factor of jet size and needle thickness anyways.  Plus the only time you're full main is at full honk.
Unlike a Holley, on bike carbs the main jet is the refrence point everything else revolves around.  You set the main for maxxx power first. Then put the needle, spring (if CV) and idle circuit around it.

Plus those RZ's are almost idiot proof when tuning. If the tune is 80% the power will still be pretty close to spot on.

[Forzfed]

I've hear some people swear by them and others say get rid of them.  My RZ with the power jets gets way better milage.  And I really like the pull when you just hit the power band with slight throttle and it keeps pulling and pulling like a big cc motor.  Below is what one company posted about them.

Here's a new twist on an old method; adding a power jet to a carburetor. Remember those? Simple power jets have been used for years as a method of improving the calibration on bigger carbs, like what sleds use. A Power jet consists of a fuel pickup in the bottom of the float bowl, connected through a fuel hose to a spray nozzle that protrudes into the incoming air stream going into the carburetor.         How and why is this an advantage? Using a power jet allows you to lean down the main jet circuit with far less fear that the engine will seize on top end, as the power jet supplies the rest of the fuel needed on top end. This has several advantages. Throttle response improves dramatically, and since most riding is done at partial throttle settings, fuel economy is improved as well. Power is improved at any temperature or elevation.   

[earlbrown]

My TZ250 came with a set of electronic valves like those described from the factory. I never could get them to make more power than just jetting accordingly.   

Keep in mind I live in 'Murica. We don't admit when out stuff don't work. We make internet posts bragging about having trick stuff 

On a 2 stroke street bike I'd rather have the bigger jet ESP if not running oil injection.  Keep in mind, during throttle chops, the rings, pistons and crank lose that lube.