Fuel Mixture

[Mickey Sergeant]

That's what I meant to Brian. Just smoke at idle.

[brian kirby]

Exactly Mickey.

Brian

[Mike Korgan]

I rode the bike yesterday, it really wanted to bog at the low and mid ranges. The top end ran good. I moved the clip on the needle up 1 notch, got noticeable improvement but I'm on the top notch. The plug is still black. Does that mean I need to look at the needle and/or needle jet?

[brian kirby]

If it is a Bing and you did not personally put a brand new needle/needle jet in it, before you go any farther you need to get them. Working on jetting a Bing is a waste of time unless you know absolutely for certain that the needle/needle jet combo are good. You can not tell by looking at them if they are good or bad, and it will save you massive headaches just getting new ones.

Brian

[Gordon Brennan]

+1 on what Brian said.
It wouldn't hurt to order more than one jet needle. I spent a lot of time and money on the 24mm Bing for my Mudlark. The needle is important and they aren't all the same. I ordered one and it didn't even feel right when I ran it through my fingers. There was a step in it. I tried it in the carb and it didn't work well. I ordered another one and I couldn't feel any steps in it with my fingers and the bike ran very crisp.
Bing parts wear out fast. At least that has been my experience with the Penton and the Husky.

[t20sl]

Pete:

Maybe I am just a glass is half empty person.  Cast carb is $375.00 and billet is $775.00.  Sounds like just another bunch of hooey.  Not even one decent picture of inside of carb.  No photo of floats, no cutaway, no parts break down and yet they want to have consumers pre buy before some models are available?  No information on why this new carb is better.  The 2 videos show me nothing that any 20 year old carb can't do.  My guess is they won't be around 3 years from now.   Just my opinion.


Ted

[brian kirby]

Ted,

It is a direct copy of a Lectron in billet. Nothing special, and its not worth the money when you can buy 2 Lectrons and a handful of needle for the price of one of those "Smart" carbs.

Brian

[JCHubbard]

Yep. I've been following a long running thread on KTMtalk.com about the APT carb.  I understand what they're saying, but I just am not buying the whole APT phenomenon.  IF I were to ever updrade my the carb on my 08 KTM 250XC, it would be a Lectron.  I'm okay with my stock carb. The only thing I've done my bike is put in a JD jetting kit and set up the suspension for my size, weight, and riding style -- the bike is good to go!  I just need to ride more!!;)

IF I were a Pro licensed/AA/Expert racer, I could understand the rationale for the need for speed. I understand buying a new FMF/PC pipe, new VF reeds, or even changing out the cylinder head, ignition, and getting some porting work done, etc etc.....I've done it in the past, but realized in the end I just need to ride more!!;)

To each his own...

[seanguthrie]

Just like John I run one bottle of golden spectro in my 5 gal gas can and fill it just to the 5 gal line.  I never notice much smoke once it warms up.  In the 3 season's I've been running the bike no engine problems besides an exploded stator which had nothing to do with my gas mix.

Also what has been said about jetting is spot on.  I rebuild my carbs every winter and sit them on the shelf for the spring.  I've never updated jets and started having similar issues with my triumph this spring.  Ordered new needle jets and it seems to have fixed my problem.  Looking at the new ones to the old ones I can not tell a difference but sure notice it when they are in the carb and working.

74 250 Hare scramble
73 CMF 6day
68 6day V213

[Mike Korgan]

Thanks for all the responses. I have a much better understanding of what is happening. The jets and needle were all replaced when I put the bike together, and only have a couple seasons on them. I don't think wear was an issue, just too rich. I ordered new jets from Bing last week and a new needle as well, just to make sure.

[adrian_goold]

We seem to have many different posts on jetting spread out over the years that we crawl through, but never get a definitive answer on what worked.
What is required is a page or link on the website that:
a) lists the stock Bing setups (ie 36 or 38 etc, type 1 54 or type 2 54 etc) and associated jetting for Pentons/KTM's. including info on your elevation and air temps etc, slide number, needle jet, needle, pilot etc.
b) lists modified setups that guys run, ie Mikuni and associated jetting for Pentons/KTM's.

Like a one stop shop for people to check out and work with as a good base line starting point.

Cheers,
Adrian

[wfopete]

quote:Originally posted by t20sl


Pete:

Maybe I am just a glass is half empty person.  Cast carb is $375.00 and billet is $775.00.  Sounds like just another bunch of hooey.  Not even one decent picture of inside of carb.  No photo of floats, no cutaway, no parts break down and yet they want to have consumers pre buy before some models are available?  No information on why this new carb is better.  The 2 videos show me nothing that any 20 year old carb can't do.  My guess is they won't be around 3 years from now.   Just my opinion.


Ted

I understand.  I've been watching some of the threads too.  From what I've heard the Lectron guys pretty much focused on the drag racing crowd for years and didn't improve the carb for off road use & this is where the Smart Carb guys jumped in. I'm just sitting on the sidelines watching it all pan out...or not.  



Pete Petrick
175 Jackpiner
Slow but Good

[JCHubbard]

quote:Originally posted by adrian_goold

We seem to have many different posts on jetting spread out over the years that we crawl through, but never get a definitive answer on what worked.
What is required is a page or link on the website that:
a) lists the stock Bing setups (ie 36 or 38 etc, type 1 54 or type 2 54 etc) and associated jetting for Pentons/KTM's. including info on your elevation and air temps etc, slide number, needle jet, needle, pilot etc.
b) lists modified setups that guys run, ie Mikuni and associated jetting for Pentons/KTM's.

Like a one stop shop for people to check out and work with as a good base line starting point.

Cheers,
Adrian

Great idea!