APT SmartCarb

[keving]

Thank you for confirming this, so I can put everything back together and go for a ride.

[Corey]

Originally Posted by keving

Does anyone have a picture of the inside of the SC float bowl? I just opened mine up and there is a black mesh like material in the bottom. I am curious if this is supposed to be here or not. I can't imagine what that may do in the float bowl.
Thanks for any help you can provide.

It's tank foam, just like you find in racing fuel cells. It's there to provide additional baffling to give the fuel pickup a tranquil area to pull fuel from. If your not doing sick whips over log jams like Wally Palmer you probably don't need it. It will last for years but can be removed easily enough if you like. Corey

[3beejay3]

Anyone have any updates on these carbs?

[siaknijustin]

Originally Posted by 3beejay3

Anyone have any updates on these carbs?

I put mine on my 300 after swapping to the shorter rod, checking slide height, checking float height and sanding the crap out of the throttle cable end. The bike started on the 3rd kick w/ choke. It hadn't been run since mid February.
Once up to temp w/ choke off, I could tell that the suggested setting was a little lean. Unfortunately, I'm waiting on rear wheel bearings and so I didn't bother with richening up the settings.

As far as float height and slide height were concerned, they were spot on as delivered (checked w/ calipers and a feeler gauge).
Sanding down the end of the throttle cable was a total PITA! I had to have spent 30 minutes on it before it would fit into the groove on the slide.

[andoman]

siaknijustin,
What overall length did you start with on the shorter rod? Would you confirm the rod number as well?
Thanks.

[siaknijustin]

Originally Posted by andoman

siaknijustin,
What overall length did you start with on the shorter rod? Would you confirm the rod number as well?
Thanks.

The shorter rod # is RO76 (There was a laser etched E12 on mine that I've no idea what the meaning is). The setting Corey provided me was 55 clicks from full rich. The longer rod is an R078 and mine came at 59 clicks from full rich. I never ran it with the longer rod because of the many reports of a lean top end.
I'm going to check the plug gap before any further adjustments because there was one report on the orange site stating that excessive plug gap had caused a lean symptom. Speaking of that, what is the factory recommended spark plug gap? I generally run about 0.034".

[andoman]

My owners manual says .7-.8mm which equals .027 to .031 in.
I have always used .030.

[Moto7man]

Any performance reviews on the cast 38s? Do they work or are they inconsistent like some of the SC billet carbs?

[siaknijustin]

I've only got about 5 hours run time on mine but I suppose that I can post an "initial impression." So far mine has been very consistent throughout all throttle openings. The only inconsistency that I've noted at this point has been the idle and the only time it's inconsistent is before the bike is up to operating temps. At that point the idle becomes more consistent that I could ever dream of my Keihin being. So far mine has seen 4k ft elevation and +or- 30f temperature changes and has run the same at all times.
This is precisely why I bought the carb; I see huge temperature and elevation swings.
For the bad (take this w/ a grain of salt): I am experiencing some of the off-idle blubber that others have noted. I am still trying to tune this out as my plug readings are still rich. Once I got the spark plug gap right and up to temp I could tell that I was terribly rich (not lean as noted above). I'm a lot closer than where I started but still not quite there. Every other throttle opening is great and top-end over-rev is better than the Keihin.
Also, on the old style subframes up to 06, the carb has to be angled all cockeyed to not make contact w/ the cases. Corey is working on a drainless float bowl for me and I believe that will relieve the clearance issue.
Overall I'm happy w/ the carb and for someone w/ varying conditions I'd strongly recommend it.
*please note that off Idle blubber isn't an inconsistency; it's always there. However, I'm confident that I can tune most (if not all) of this out.
I'll post more as I go but realize that I don't get out near often enough.

[Moto7man]

Thank you for the post/update! I have read all the postings here and on KTM Talk. I am seriously considering this carb. It seems that there won't be any 38s available until late October anyway.