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Carburetor... So simple, yet so confusing... Any experts on these?

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Been trying to dial in my carb in the past couple days after it running real rich spitting spooge everywhere. I have been advised switch oils because what I'm running is klotz r50 and people are saying switch to maxima super m for less smoke and spooge but I know that a properly tuned carb will fix this issue so the oil is not the issue. I know people who run it no problems. Mixing 32:1 main is a 172 and pilot is a 42. Needle is at lowest position (clip is at highest). What really confuses me is the following ; I checked my float level and it is actually much lower then stock specs which should make it starve for fuel running leaner... But it runs rich. My jetting is already much leaner than stock, will raising the float to the correct specs make it run even richer or could that be my issue all along?

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Float level just checks how much fuel is in the bowl.  It wouldn't make it leaner to have it too low, and I don't see how it would make it richer, either, but definitely adjust it to spec.  The carb is pulling gas from the bottom of the bowl. There are carb experts on here, and lots of resources on search, and there is even a recent article in DirtBike about spooge coming out the back.  Mr. Know It All.  Love that guy.  Anyway, good luck and you know you will get better machine specific advice if you divulge the make/model.  

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Float level just checks how much fuel is in the bowl. It wouldn't make it leaner to have it too low, and I don't see how it would make it richer, either, but definitely adjust it to spec. The carb is pulling gas from the bottom of the bowl. There are carb experts on here, and lots of resources on search, and there is even a recent article in DirtBike about spooge coming out the back. Mr. Know It All. Love that guy. Anyway, good luck and you know you will get better machine specific advice if you divulge the make/model.

Thanks for advice and I apologize, 2001 ktm 200exc keihin pwk 39 carb I do believe
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float height will effect jetting slightly due to changes in negative pressure required to suck fuel through the jets. The float height is the first thing that needs to be set when jetting. Another thing that may be a factor if you have a really high hours bike is needle and needle jet wear, they wear slightly over time creating a rich condition.

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I have heard that float level does make a difference to the flow through the jets. This may be academic:

I dont know how much merit there is to the theory but basically it goes like this:

More fuel, means more weight/pressure on the fuel. This causes fuel to flow faster out of / through the jets. Too low, and you're flowing slower.

Most measurements are given + or - 1 millimeter. Thats fairly small and hence you need to be precise, but aparrently it makes a difference. Personally, I've noticed the difference in my car, and my street bike.

Some reading:

http://www.advrider.com/forums/showthread.php?t=110771

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float height will effect jetting slightly due to changes in negative pressure required to suck fuel through the jets. The float height is the first thing that needs to be set when jetting. Another thing that may be a factor if you have a really high hours bike is needle and needle jet wear, they wear slightly over time creating a rich condition.

 

and this. Thanks, needle and seat condition I forgot completely about.

My RGV250 was shooting raw fuel out the right hand side tuned pipe when I first bought it because of a damaged seat in the RHS carb, but not the left. Engine ran fine on one side, keeping it turning, RHS ran like a fuel pump. :eek:

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UPDATE: went to local dealer today and bought new jets. I went from a 175 main to a 170 main and a 40 pilot to a 38 pilot. Still running 32:1 klotz seemed to give good throttle response right off the bat. Smoke was less than normal sounded cleaner. DEFINITELY noticed a huge power gain while I was having a blast wheeling just by touching the throttle. Going to do this "plug chop test" to make sure I'm not running to lean. But the symptoms don't seem like I'm running lean as there is no bogging, no hesitation. Only ran bike up down street for 5 minutes. Gonna check plug see what it reads but again, hoping I'm not running to lean but I'm just paranoid!!

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One reason I quit using KLOTZ R50 was the spooge..    Me and everyone else around here who ran it in our bikes mixed it 50:1..  Kotz recommends 40:1 -50:1.  Personally I think that for trail riding, etc there are better oils IMO..   Klotz seems to burn cleaner when you are in the upper rev range constantly.  Such as in racing.. Spectro was another spooger..  One more thing.  To help you're emgine live longer go find some Yamaha "Ring Free"..  It'll really help cut down on carbon in the top end  and keep the rings loose.

Edited by zilla

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and you never said which bike it is..I would guess a 200 due to the jet sizes

Yes you are correct, and I did say above what bike it is

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One reason I quit using KLOTZ R50 was the spooge.. Me and everyone else around here who ran it in our bikes mixed it 50:1.. Kotz recommends 40:1 -50:1. Personally I think that for trail riding, etc there are better oils IMO.. Klotz seems to burn cleaner when you are in the upper rev range constantly. Such as in racing.. Spectro was another spooger.. One more thing. To help you're emgine live longer go find some Yamaha "Ring Free".. It'll really help cut down on carbon in the top end and keep the rings loose.

what oil did you change to? I feel like after the new jetting the klotz is performing better an I know it is a bit of a thicker heavier oil providing better lube and I like that.

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Not sure why you'd use r50 on a trail bike.  It has a super high flash point and even their own literature recommends it for 10krpm+ applications.

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Not sure why you'd use r50 on a trail bike. It has a super high flash point and even their own literature recommends it for 10krpm+ applications.

Then what do you recommend

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Personally I like motul 800 or whatever it is @ 40:1.

Sometimes my engine gets the living shit revved out of it.

Might give the motul 800 a try or maybe the maxima super m. Thanks

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Then what do you recommend

 

You can run pretty much any brand name oil nowadays as they're all quality products.  If you care about build up and excessive unburnt oil then pick one with a lower flash point.  If you don't then rock your r50.

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