Cr125 bottom end sputter

When Im I'm riding around and I'm in lets say 3rd or 4th gear in sort of low rpm's and I give it some gas, it sputters a lot. Also there's a lot of spooge. I'm running 32:1 mix and I think It could be that I'm running too rich. What do you think?

What type of riding are you doing?  What is your current jetting including your air screw? Smaller bore 2 strokes tend to run better in the higher rpm's and can load up when running in the lower rpm's.  Mixture is fine as long as you are jetted appropriately for the type of riding you are doing?

If you cruise at a low rpm for a bit, and then you begin to accelerate and it sputters/blubbers, but it begins to clear out as you continue to accelerate, then you're probably running too rich.  Not on oil, but on jetting.  If you're riding hard all the time and on the pipe, then too rich won't hurt anything other than maybe some loss of horsepower. 


But if you're a casual rider and your jetting is too rich, you can leave it that way, but you'll just have to clear it out every so often, and deal with some spooge.


It may be as simple as moving the c-clip on your metering rod up one slot.  Just be careful not to lean it out to much. 

I do woods and some cruising on snowmobile trails. When I get into the powerband it runs great it's just under acceleration in low rpms

Try moving the c-clip on your metering rod, up one groove.  If that clears it up great, if not then you may need to try a smaller main jet.  If it does clear it up where it's smooth and very responsive, you can still get it on the pipe, but if your not sure how lean your mixture is, I wouldn't hold it pinned for long periods of time until you have some help with the jetting.


Jetting a 2-stroke isn't complicated, it's time consuming.  Getting the pilot jetting correct, then for it to transition into the metering rod and then onto the main jet in one smooth hit of the throttle, is an aquired art.  After some experience, you'll be able to listen to the exhaust while reving the engine, and have an idea where you stand on the mixture. 


If you're going to race only and stay on the pipe, warm the engine to full operating temperature on an old spark plug.  Then stop and install a new plug.  Start it up and as some as you can get the bike up to race speed for several laps.  When you're done, try not to idle to long back to the pits, as this can give you a false plug reading for the desired race rpm jetting.  If you have to, shut it off and push it back to your pits.  Then pull the plug and look at the color of the carbon on the porcelan.


If you're going to ride casual and ocassionally be on the pipe, you can still read the plug for an overall stance on jetting.  But you can listen to the exhaust as well.  But then when you think you know what you're doing, the weather changes and so does jetting.  I only race mx so I keep mine 2-strokes a little on the fat side, so I don't have to change the jetting.....or replace a smeared piston.


There are probably some members on here, or some sites that can give you an idea on what jetting for the type of riding you're doing, along with altitude, humidity, baro and type of fuel you're burning.

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