APT Smartcarb

[vagassasson]

Hmmm this might throw a wrench in my plan of using them for a Turbo k5 ... they did sound a little to good to be true    . They did promise me dyno time if I get the k5 Turbo working so long as I use an apt smart Carb

[RoostiusMaximus]

I'm not ever going to say that Corey Dyess isn't a 2-strike lover that'll go out of his way to help you. But the rest of the crew there kinda doesn't have the same enthusiasm.

You'll need a cultivator spring for the slide! Haha. The stock ones are so lite that a good cr5 intake signal will draw that slide open on its own. You can see it by looking in the airboot at idle while shining a timing light strobe in there.

[Brute]

"The stock ones are so lite that a good cr5 intake signal will draw that slide open on its own."

That is,,, really, really, not good. Really. Seriously. Not. Good.

[Mike Grant]

Rootius Maximus.......curious to the jetting you have found works for cr500 with a 38mm pwk airstryker.....I have a  58 pilot with a 165 main jet  with a DGL needle in the third clip on my 87 K KX500 Seems crips but I am not a carb tuner pro compared to you . I am running at around 700-1500ft above sea level at at around 5-15 degrees Celsius.  I've cracked the throttle open a few times and it seems very close but I do not want to burn the top end up because I'm not understanding what the engine is looking for......on a side note the work you have done for me sounds so clean and crisp compared to other bike of the era..... amazing attention to detail.......passed on your name to many on the west coast here......hope I can put some extra $$ in your pocket. Most common thing I am asked about after refering you is if you are able to to re=coat cylinder.....not sure if that is up your alley

[Friar-Tuck]

 I know I'm way late to the game  here, but I have run the 38 a.s. on my old '85 cr5 and my kx5 with no issue,  most guys are looking for more power.
   I wanted more low mid as I was riding from 3000 to 6000' and 13 or 14/51 (10mph or so 1st gear) single track skidder and fire roads with guys way faster than me.  Up here you rarely have the oppty. to get to 5th let alone wfo.  I never had any issue with short wfo 4th/5th as there was less than a mile or two to get it.     If you are looking for low/mid throttle response the improved velocity of the 38 worked for me.   There are some of my old posts here, but I think my cr5riders may be long gone... RoostMax has done some great work search his stuff on both sites.
you can't go wrong...Tuck\o/

[motojason]

There is a letter response in Dirt Rider written by Editor Adam Booth this month regarding the APT carb. He said something similar (to roostmax) regarding 3/4+ throttle lean operation. Letter stated he blew up his personal KTM 300 using this carb with major damage to the top end sustained.    

[RoostiusMaximus]

Mike Grant, Haven't run a KX here yet, won't be on a standard PWK when I do either, going pulse induction.
The K5 generally takes more pilot than a CR, the numbers you're at is about what I'm hearing.
I'd only have Millennium plate cylinders, I don't do that work.