volt9
New Member
I just recently installed an SBP expansion chamber as well as a new air filter (also SBP) and was mucking around with the needle settings in an attempt to minimize some 4-stroking. After some minor experimentation, the second highest setting on the needle seemed to provide the best overall drive. Runs perfect at 50%~100% throttle and only 4-strokes (ocasionally) when cruising at 1/4 throttle or under a light load (like a mild downhill slope). I don't think I can get it to run any better than it is now. But I am more than satisfied with what the SBP pipe has provided...well worth the money.
Anyways, while I was playing with the e-clip on the needle (and looking at the throttle cable) something occured to me. What's the starting point when you are setting the idle? What do I mean? Well, from what I can tell, there are two ways to raise or lower the idle. 1. you can use the screw designed for exactly that purpose, or 2. you could adjust the actual throttle cable (which effectively raises and lowers the needle) thereby achieveing the same result. Which way is better? And why?
The way I have it set now, is that I have the throttle cable adjusted 'just' to the point where there is no obvious slack in the cable, so any amount of movement from the throttle will result in raising the needle. If I adjust it any lower (the nut on the cable I mean), the cable becomes a little slack and the first few mm's of throttle rotation don't actually move the needle at all. (and you can feel it because there is far less tension until the needle starts to raise) I think the way I have it sounds right, but would like to hear how other more experienced MB riders do it.
So to get back to my first question, what's the starting point? Maybe what I should be asking is ; what to adjust first? Throttle cable? Or idle screw? And when you are turning the idle screw, what's actually being adjusted inside the carb?
BARRY
Anyways, while I was playing with the e-clip on the needle (and looking at the throttle cable) something occured to me. What's the starting point when you are setting the idle? What do I mean? Well, from what I can tell, there are two ways to raise or lower the idle. 1. you can use the screw designed for exactly that purpose, or 2. you could adjust the actual throttle cable (which effectively raises and lowers the needle) thereby achieveing the same result. Which way is better? And why?
The way I have it set now, is that I have the throttle cable adjusted 'just' to the point where there is no obvious slack in the cable, so any amount of movement from the throttle will result in raising the needle. If I adjust it any lower (the nut on the cable I mean), the cable becomes a little slack and the first few mm's of throttle rotation don't actually move the needle at all. (and you can feel it because there is far less tension until the needle starts to raise) I think the way I have it sounds right, but would like to hear how other more experienced MB riders do it.
So to get back to my first question, what's the starting point? Maybe what I should be asking is ; what to adjust first? Throttle cable? Or idle screw? And when you are turning the idle screw, what's actually being adjusted inside the carb?
BARRY
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