APT SmartCarb
- Thread starter gasgasman
- Start date
Gasgasogeros
New member
Euro bikes needs euro carb try amal, bing,end delorto, 
Rick
New member
Euro bikes needs euro carb try amal, bing,end delorto,
We all need a tickler on our cab as well:
.....I'm sure there is a 100 good reasons why we don't use a Bing anymore!
djroggen
New member
Jakobi,
Your problems intrigue me. You seem to always have jetting issues! You must be awfully picky... I don't want to come off in a bad way but do you have any videos of you riding your motorcycle?
I only ask because sometimes depending on the application it seems that many issues arise from how one rides the motorcycle.
I have only tried 3 setups for any length of time and that was over a 2 week period over 2 years ago. One of the setups was the factory spec garbage that was in it. Never had any issues, none, nada with the jetting ever. I don't even know what jets I am running (it has been soo long since I have touched them), I even sent off my carb to RB Designs last fall. He rejetted it, I ran it for maybe 10 mins and switched it all back to the original jetting he sent back in a little baggie that I had become accustomed to. Even with his mods, was a 36mm now a 39mm AS II. Still have not had an issue. I believe the needle I am running is an N3CH. I know for an absolute fact that jetting is entirely subjective. I know that one needle I tried, was an absolute fire breathing dragon. I guarantee you hand that motorcycle over to some hack job kid who doesn't know better, and he will think that is awesome. I bet it even makes more HP. No thanks.
The whole SmartCarb theory is a good one. It is a solid carb that "just works." I hate to compare things that I have never tried, but this is my comparison FWIW. A SC seems an awful lot like an iPhone, they work incredibly well for the masses, but for the picky guy who wants to be able to tinker and make it exactly what he wants, he may be out of luck. I for one am an iPhone user and I love it. I used to tinker with my Droids, then I decided it was quite a bit more fun to ride my motorcycle than tinker with my damn phone.
I hope I didn't start a fight. Maybe the Aussie air is kinda like helium, and cannot work with a carb?!?
Your problems intrigue me. You seem to always have jetting issues! You must be awfully picky... I don't want to come off in a bad way but do you have any videos of you riding your motorcycle?
I only ask because sometimes depending on the application it seems that many issues arise from how one rides the motorcycle.
I have only tried 3 setups for any length of time and that was over a 2 week period over 2 years ago. One of the setups was the factory spec garbage that was in it. Never had any issues, none, nada with the jetting ever. I don't even know what jets I am running (it has been soo long since I have touched them), I even sent off my carb to RB Designs last fall. He rejetted it, I ran it for maybe 10 mins and switched it all back to the original jetting he sent back in a little baggie that I had become accustomed to. Even with his mods, was a 36mm now a 39mm AS II. Still have not had an issue. I believe the needle I am running is an N3CH. I know for an absolute fact that jetting is entirely subjective. I know that one needle I tried, was an absolute fire breathing dragon. I guarantee you hand that motorcycle over to some hack job kid who doesn't know better, and he will think that is awesome. I bet it even makes more HP. No thanks.
The whole SmartCarb theory is a good one. It is a solid carb that "just works." I hate to compare things that I have never tried, but this is my comparison FWIW. A SC seems an awful lot like an iPhone, they work incredibly well for the masses, but for the picky guy who wants to be able to tinker and make it exactly what he wants, he may be out of luck. I for one am an iPhone user and I love it. I used to tinker with my Droids, then I decided it was quite a bit more fun to ride my motorcycle than tinker with my damn phone.
I hope I didn't start a fight. Maybe the Aussie air is kinda like helium, and cannot work with a carb?!?
StuJohnson
New member
So now were talking about phones ... I myself like my Android phone.!!! 
swazi_matt
Active member
I doubt j will take offence. He has on numerous occasions admitted to being a bit ott about jetting, but that is why he is the go-to guy when you have any jetting issues
We're using the next couple days for additional durability testing and the fix for the bogging issues that showed it's ugly head last week at the X games. The cast carbs have a larger area under the nozzle pickup because of the float bowl drain. Forcing us to change the anti slosh baffle to take care of the bogging. Tomorrow I have Knobby Hill MX track in St. Joseph MO rented out and if it's not another downpour we'll have Alex Mallot and myself airing several of these things out. Hopefully it's a fix. Too bad you guys aren't a little closer I could use the extra help. TJ where's that 2014 GG 300 that was supposed to be here today?
You'll hear from us Monday morning.
Jakobi
Super Moderator
No offence taken.
I know pleanty of people who have got along with the stock needle just fine too. The thing with jetting (as with most things), the best you know is the best you've tried, and once you've experienced something great it kind of sets the standard for which you aim to achieve. Sometimes this isn't always possible, so then you need to decide how much you are willing to compromise.
Now, I have spent considerable time working with the PWK carb, so you could say the knowledge or experience of whats possible is there. The expectations of the Lectron and Smart Carb were both high as well. Both companies make a lot of claims as to their advantages. Is it wrong to expect them to run clean from top to bottom? I mean, thats what they all promise..
I think your analogy re the Iphone is close, but is highly dependant on your definition of 'just works'. For me, personally, I experience the same as drewhurm and his friend, that to get the mid to top to run strong I need to deal with an overly rich bottom end, or vice versa. After trying 2 x metering rods, double checking the carb seals, running it on a known engine, with a known state of tune, I'm at the point where I can either a) modify it to meet my expecations, or b) have APT buy it back off me and put me down as one of the few who aren't happy. I've seen the carb run well at certain points, at different times. It has potential and I will work with it to get it to run. I like that its sealed, and the fuel economy has been good too. Its not all bad.. but its not the greatest thing either. A bit like those IPhones. A lot of people buy the hype..
All my videos are available here
I know pleanty of people who have got along with the stock needle just fine too. The thing with jetting (as with most things), the best you know is the best you've tried, and once you've experienced something great it kind of sets the standard for which you aim to achieve. Sometimes this isn't always possible, so then you need to decide how much you are willing to compromise.
Now, I have spent considerable time working with the PWK carb, so you could say the knowledge or experience of whats possible is there. The expectations of the Lectron and Smart Carb were both high as well. Both companies make a lot of claims as to their advantages. Is it wrong to expect them to run clean from top to bottom? I mean, thats what they all promise..
I think your analogy re the Iphone is close, but is highly dependant on your definition of 'just works'. For me, personally, I experience the same as drewhurm and his friend, that to get the mid to top to run strong I need to deal with an overly rich bottom end, or vice versa. After trying 2 x metering rods, double checking the carb seals, running it on a known engine, with a known state of tune, I'm at the point where I can either a) modify it to meet my expecations, or b) have APT buy it back off me and put me down as one of the few who aren't happy. I've seen the carb run well at certain points, at different times. It has potential and I will work with it to get it to run. I like that its sealed, and the fuel economy has been good too. Its not all bad.. but its not the greatest thing either. A bit like those IPhones. A lot of people buy the hype..
All my videos are available here
Jakobi
Super Moderator
Is that the same issue that they just identified with the cast models too? Something to do with the drain hole?
In other news I'm going to have a go at modding my R080 today as per Michaels suggestion. I'm thinking I'll work through 5 strips of wet and dry, and then resinstall. I won't actually get a chance to try it properly until Friday.
Jakobi
Super Moderator
Just an update.
I did as michael did and used some wet and dry. I only had P1200 in the workshop or P800 so went with the finer grit. Followed the directions of applying force 1/3rd from the end/bottom of the metering rod. Went through 6 strips the length of the rod and then reassembled and did a quick 10km test ride. No good. Still had a rich burble off the bottom, and a bog that quickly followed, and then the bike came into fuel and ran well. Very much same as stock, possibly worse. During this testing I went from my previous length of 99.75mm to 100.40mm to try and clean it up. Still wouldn't clean the bottom end, and accentuated the lean hesitation at 1/8-1/4 throttle.
I pulled the MR again, and then worked through the same 6 strips again which had been somewhat dulled down and focussed on working more of the middle of the metering rod, and generally just lapping the entire face until the machining marks on the flat side no longer existed. Reassembled and tested again. Immediately the bike settled into a great idle. Rode well. Pulled strong and was somewhat clean, but torquey off the bottom. Easily the best setting as of date. I went one click leaner and this cleaned it up more, but left it a bit lean through the mid (as identified by a racing idle after doing 1/2 throttle runs). No worries. Back one click richer, and its as good as it needs to be. As clean as my AS2 was, gains in the mid range, and a healthy top end. The bike will idle on the stand for ever with no signs of hanging, or flaming out, no hestitation when cracking the throttle, and no smoke under throttle either. It does smoke a bit as the revs fall but thats pretty typical. Definitely not like a chimney or anything.
I'm going to have to take it for a decent ride later in the week, but for now I'm very impressed.. Finally. Makes me wonder if the stock MR just needs a good lapping from the get go. Anyone else want to try?
I did as michael did and used some wet and dry. I only had P1200 in the workshop or P800 so went with the finer grit. Followed the directions of applying force 1/3rd from the end/bottom of the metering rod. Went through 6 strips the length of the rod and then reassembled and did a quick 10km test ride. No good. Still had a rich burble off the bottom, and a bog that quickly followed, and then the bike came into fuel and ran well. Very much same as stock, possibly worse. During this testing I went from my previous length of 99.75mm to 100.40mm to try and clean it up. Still wouldn't clean the bottom end, and accentuated the lean hesitation at 1/8-1/4 throttle.
I pulled the MR again, and then worked through the same 6 strips again which had been somewhat dulled down and focussed on working more of the middle of the metering rod, and generally just lapping the entire face until the machining marks on the flat side no longer existed. Reassembled and tested again. Immediately the bike settled into a great idle. Rode well. Pulled strong and was somewhat clean, but torquey off the bottom. Easily the best setting as of date. I went one click leaner and this cleaned it up more, but left it a bit lean through the mid (as identified by a racing idle after doing 1/2 throttle runs). No worries. Back one click richer, and its as good as it needs to be. As clean as my AS2 was, gains in the mid range, and a healthy top end. The bike will idle on the stand for ever with no signs of hanging, or flaming out, no hestitation when cracking the throttle, and no smoke under throttle either. It does smoke a bit as the revs fall but thats pretty typical. Definitely not like a chimney or anything.
I'm going to have to take it for a decent ride later in the week, but for now I'm very impressed.. Finally. Makes me wonder if the stock MR just needs a good lapping from the get go. Anyone else want to try?
DirtRider Magazines initial impressions of the SC.
http://www.youtube.com/watch?v=XbBkt2_pZNM&feature=share&list=UUJmqHA6DW_LayTijWSMecQQ
It is amazing how clearly it shows that there is something different, isn't it! I disagree with the "just lapping" comment since we are talking about changes in the 0.01mm range that actually make a difference. I think you still have "potential" to get it even better ...
I had that effect too and it is a function of nozzle tolerances so there is not much you can do about it. Right now I'm using a super-tight in- and outside- tolerance nozzle with no counter bore at all and it completely eliminated that effect. To make that work I had to ream out the carb-body though for perfect fit and alignment so that is just another climax of me going completely crazy with the SC. Reward of that is an extremely clean running SC and an amazing powerband on the 300 - smooth and linear was a bit boring at times, so now I'm at smooth and progressive
BTW the transition to the 300 kit with optimized head was pretty painless - 2 clicks richer and that was it. It looks like the SC is really consistent as promised - either consistently bad/average or consistently good
Reality check: my riding buddy has a 2013 300 which is basically the same engine which I jetted for our needs using the Suzuki needles and that bike runs very, very well also. It might not have the broad powerband the SC has, might smoke and spooge a little, looses fuel through the overflow, BUT regardless is major fun and runs, as I said, really well. So in retrospect was it worth almost 1000 USD and countless hours of tinkering - well, better don't ask - often knowledge is said to be priceless, but I guess there are exceptions ...
Michael
Jakobi
Super Moderator
I think you've summed everything up well.
Not much more to add here. I agree there is probably more potential to be unlocked, but lapping on wet and dry is very much a trial and error process. I'm not sure its the right approach, but its definitely worked in my case. I don't know if it was my particular engine or not, but yours is the same, and both are new and of known states of tune prior to making changes.
The little smoke on decel doesn't concern me. It'll be interesting to see if it starts to load up in the single track though.
Not much more to add here. I agree there is probably more potential to be unlocked, but lapping on wet and dry is very much a trial and error process. I'm not sure its the right approach, but its definitely worked in my case. I don't know if it was my particular engine or not, but yours is the same, and both are new and of known states of tune prior to making changes.
The little smoke on decel doesn't concern me. It'll be interesting to see if it starts to load up in the single track though.
Here's the follow up article from DirtRider....5hp/13% gain in hp.
http://www.dirtrider.com/features/b...rt-rider-dyno-the-weekly-dirt-august-14-2013/
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StuJohnson
New member
Here's the follow up article from DirtRider....5hp/13% gain in hp.
guessing you forgot to paste the link
Uh mm...yep!
arminhammer
New member
Here's the follow up article from DirtRider....5hp/13% gain in hp.
http://www.dirtrider.com/features/b...rt-rider-dyno-the-weekly-dirt-august-14-2013/
Sure wish mine worked well. I have a crap load of time spent on it and it has become a $1000 conversation piece on my work bench.
