APT SmartCarb

[Fred1956]

Originally Posted by fasteddy

That one didn't work for me.. Try this. Oh by my the way...... APT looks to be sold.... Hmmmmm

http://www.marketwatch.com/m/story/f...3-9f564e7ad205

This one worked for me...http://money.cnn.com/news/newsfeeds/...re/1043267.htm

[Motosportz]

Interesting / Weird. Both APT and MotoVOX websites are down now. And the ProTek company looks odd (website looks unfinished and missing a bunch of stuff)... http://protekcapital.com/index.html

[AZRickD]

I am not a fan of "news" organizations lazily reprinting press releases verbatim.

[Jakobi]

I still can't gel with this carb. There is something about it that I can't put my finger on, but its inconsistant. IE I'll start it, run it, dial it in well, have it so it idles on and on and on and doesn't hang after putting a big load on it, and then put it away. Go and ride it half an hour later and it'll have a hanging idle, or run rich, blow smoke and spooge. Maybe its the floats hooking up or the needle not seating? I don't know but I've had a gutful of it.

Add to that that I did a bit more tinkering today to get it dialled in and now its gone from running clean to a bit more smokey and spoogey. The power is grunty though. I'm a bit lost with it all. My experience with this has been anything but plug and play perfection.

[Jakobi]

I've gota big 2 day ride coming up, and currently stuck and not sure where to go from here. The bike feels like its running strong top to bottom, however is now showing signs of both being rich and lean together. Rich as in I have a small dribble of spooge at the tailpipe, which may just be a result of some testing I'd been doing and loading the packing up with some excess oil (heres hoping). Lean symptom is a hanging idle after giving it a good buzz along. Torque spread is very good across the rev range, and I think the lean hang is mostly caused when riding high in the revs, with under 1/4 throttle. If it was a Keihin I'd go up 1 needle diameter and it would be great.

I also found the slide height has very little influence on the idle speed. IE it takes considerable adjustments to make a change in idle, however it has a massive effect in off idle torque and cleanliness. It also adds to the hanging idle effect if having the slide up too high. The issue I face is that going a click richer on the MR means lifting the slide some more to maintain the idle, which kind of defeats the purpose of richening it up, as the adjustment then leans off the lower openings again.

I'm hoping the latest round of mods to the MR haven't negatively impacted fuel economy as I need to stretch a 90km section.. I'll have 1L in the back pack. Last week doing a similar loop of 70kms I used 6.4L, but the spooge is scaring me. Every other time I've seen it I've seen fuel economy suffer.

[n_green]

Want me to send your keihin back up mate?
That sucks you're still struggling with it.
Do you think it's possible it is simply a 'bad' carb. If so what are the chances of swapping the whole thing for a new one to see??

[Jakobi]

I guess I could put that to Corey. Maybe I'll see if he'll let me sample a Cast when they hit production for comparisons sake.

You can hold onto my Keihin a bit more yet Nath. I've still got TSPs Lectron here if things get really bad. After this weekend I'll pull the whole Smart Carb and double check the floats, inspect for wear and damage, fix the MR to stop it rotating, and maybe lightly sand it a little more where I think the straight section would typically be. I don't have much of anywhere to go with the R080 rod anymore as I'm at 90 clicks out to compensate for my orginal lapping. At the moment I think I'm a bit rich back towards WOT too, but I'm still getting around 9100rpm on the taco and not breaking up so it can't be too rich. I've got to pull the shock for a revalve so might as well treat the carb at the same time. I was hoping I'd be using this time to send the SC to TSP for Dyno time. Might yet depending on how the weekend progresses.

[drehwurm]

Originally Posted by Jakobi

I also found the slide height has very little influence on the idle speed. IE it takes considerable adjustments to make a change in idle, however it has a massive effect in off idle torque and cleanliness. It also adds to the hanging idle effect if having the slide up too high. The issue I face is that going a click richer on the MR means lifting the slide some more to maintain the idle, which kind of defeats the purpose of richening it up, as the adjustment then leans off the lower openings again.

I have seen the exact same symptoms before I got my rod/nozzle sorted. One thing you can try is to go in really far with the slide stop till there comes a point where the RPMs finally react to the slide height and work from there.

Michael

[rosco]

A leaky float valve can deffinately give you those symptoms. If you set the idle high enough so it will idle consistently for a period of time well then it is too high after you run it at higher rpm's. This will give the bike a lean feeling when coming down from higher rpm's. You might try shutting the gas off while it is idling and see what kind of feed back you get. I know this is stuff you already know, but sometimes a guy gets so rapped up in a problem that we forget to try some of the simple things.

[Motosportz]

Originally Posted by Jakobi

I also found the slide height has very little influence on the idle speed. IE it takes considerable adjustments to make a change in idle, however it has a massive effect in off idle torque and cleanliness.

This to me based on my Lectron experience is caused from to rich rod at the initial setting. If the slide opening is about typical for a good idle yet you cant change the idle much it is rich. If the idle if erratic and sensitive it is lean. This is a slide to rod position thing. Lectron tells me it is this critical area, at idle and just off idle, that is the most important part of the rod profile. The super small slide opening, high velocity, and super small opening at the base of the rod is very sensitive to this setting. The issue if you don't have the rod profile super dialed you can get the bike to idle nice but might have a huge bog as it is lean all of a sudden when you open the slide. If the rod profile is not spot on you have inconsistencies and cant get both a good idle and good bottom end. As you have found from sanding the rod, taking .0001 off can make a difference. This shows the rod profiles on these are very critical. They like lean at idle but need to ramp up to rich pretty quick right after that so no bog or soft bottom end. Sounds like your rod does not have the profile to support the needed lean idle AND ramp up so you have good bottom. You have dialed it so it runs good and has good torque (rich) but this is making it run erratic at idle.

How does it start hot? Do you need your choke when cold or no?