So im running my rt carb with the 60 jet and it is still running rich. Fourstroking at wot and takes a while to warm up. I have a pleneum intake manifold and ive heard it gives more low end at the risk of the top. Im 250 lbs so im cool with the low end. But at what point does the smaller jet affect overall performance? And does dax carry a smaller jet than a sixty for the rt carb? Mabe i should just run a high preformance oil at 50 to 1 to thin out the mix?
rt carb question
- Thread starter scottyskidoo
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If I recall correctly you are running the intake from CRmachineman (Fred). Have you tried to contact him directly for suggestions? He does a lot of testing and I wouldn't be surprised if he had tested this configuration. I was having some issues at WOT also but switched to a 70 jet after trying a 60. The 60 bogged on the stand. The bike still dogs a little on the hills but it's a very heavy bike I'm about that 200 lb mark myself with clothes and helmet and such. I also put on a Puch head that cools a little better and lowers he compression. Might be the later that tames the four stroking at the expense of power for me. Not sure if my experiences help or not but for sure get a hold of Fred if that is the intake you installed.
Maybe you need to do a float adjustment? If the float lets the fuel level in the carb bowl sit too high the carb will generally run rich.
If you run less oil in your gas (re 50:1 as opposed to 32:1) you mix will get more rich, as more gas will be getting through your jet in place of the oil...
If you run less oil in your gas (re 50:1 as opposed to 32:1) you mix will get more rich, as more gas will be getting through your jet in place of the oil...
A plenum chamber should have minimal effect on jetting.
Pirate Cycle, and Sick Bike Parts, both sell the jets you need. All you need to do is figure out what size jet your carb uses, 5 or 6 mm?
The NT uses a 5 mm jet. My DAX carb has a 6 mm jet. Some of them use a 5.
Pirate Cycle, and Sick Bike Parts, both sell the jets you need. All you need to do is figure out what size jet your carb uses, 5 or 6 mm?
The NT uses a 5 mm jet. My DAX carb has a 6 mm jet. Some of them use a 5.
Thanks for the input guys i guess im just gonna have to buy some jets and play around with em. So the needle on the rt carb cant be adjusted? All the tuning is done through the jeting correct?
What is your oil ratio? I was at 70 and went to a 65 and boy did I find the sweet spot. There was no "loss in top end" when I did that. I can't imagine below a 60 is right. Is your air filter clogged?
My carb used the 5mm jets. Jets are the only way to tune this motor. I think this carburetor comes with a bunk air filter. I bet you that if you took off that air filter you would lose the 4 stroking. Don't run it for long like that though. You might try some other kind of air filter? I don't know, but <60 jet sounds too low to me.
My carb used the 5mm jets. Jets are the only way to tune this motor. I think this carburetor comes with a bunk air filter. I bet you that if you took off that air filter you would lose the 4 stroking. Don't run it for long like that though. You might try some other kind of air filter? I don't know, but <60 jet sounds too low to me.
I tried every jet that came with my dax and the 70 was the best. I have phenominal low end as well but nothing at wot. Best I get is about 25mph. Its smooth and quiet at 22. Peaceful even. The intake extention puts the bowl at a forward angle so maybe ill try twisting the carb left or right to see if the float position is an issue at all. Again there isn't a hill in my little town I haven't been able to climb. Very impressed. May even be able to drop to the 41 tooth I have.
Yeah i got some time tomorrow before work and im gonna change back to the 65 to see if that helps. as far as air filters its clean however i am in the market for a new one. Ive seen that 90 degree bend air filter on sbp and i wish they made one for the rt! right now im running at 35 to 1? well whatever the stock requirement is. Also i probably need to be running a better oil. Lol go figure on my way back from work the cheap ass spark plug connector came loose so now i have even more problems. wanted to get an nkg cable anyways...
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What does it mean when I'm going up a hill and I get the intermittent rushes of power? I can't take my hand off the handlebars because the power really comes on. I can't figure out for the life of me how to make that the norm. The power I mean. I dropped to the 65 jet and no real difference from the 70.
I seem to recall reading about that in this thread: http://motorbicycling.com/showthread.php?t=30472
It's a long one so I hope I have that right.
It's a long one so I hope I have that right.
The angle of the carb is making the float act different when you are on a hill, so perhaps you will be able to make that the norm by adjusting the float setting.
That said, two stroke motors sometimes really start to scream when they are under a heavy load, my toro snow blower always seems to be happier when it is digging into a fair amount of snow. So it may just be the load on the motor that makes it seem like it is really pulling stronger and hitting the sweet spot...
I added some hose onto the intake to get the bowl level. Runs much much better. In fact, after installing the 41T sprocket, it runs great! Not fast (26-28mph) but smooth and still with enough torque for the hills in my area. I think you're right in that these little engines are happier with a load. NAMASTE VRUM VRUM
