Two-Stroke dirtbikes question
01-28-2018 | 12:40 PM
#62
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From: Seaford, VA
Okay - it was definetly too rich. Played with needle jet in all positions and it runs best in position 1. I guess I'm a little surprised - I would have thought that with aftermarket pipe (FMF Gnarly and Turbinecore 2) it would have flowed more and needed more fuel. It's still a little "jerky" and smokes a little so I'm thinking of going to a fatter needle, which I have from a spare carb. Right now I am running the stock needle.
Any value in switching to a needle that allows you to run in a more "middle clip position" - or if it runs good in position 1 just roll with it....
Also read a lot about these carbs being sensitive to float level being within spec. So sorted that out.
Side note. This thing appears to be pretty fast.
Any value in switching to a needle that allows you to run in a more "middle clip position" - or if it runs good in position 1 just roll with it....
Also read a lot about these carbs being sensitive to float level being within spec. So sorted that out.
Side note. This thing appears to be pretty fast.
Last edited by seafordguy; 01-28-2018 at 12:53 PM.
01-28-2018 | 04:22 PM
#63
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From: Toledo Oh
A good pipe can actually make a bike run richer as it has a better return pulse to keep the new fuel charge from escaping.
As for the needle, length diameter and taper all effect mid throttle jetting.
As for the needle, length diameter and taper all effect mid throttle jetting.
01-28-2018 | 07:53 PM
#64
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From: Seaford, VA
I have a wider needle but it's wider to the naked eye so I'm not going to bother. I also noticed I have a leaner slide. Going to figure out tomorrow if it's a #7 or #8 - stock is #6. Then order a leaner needle and just experiment a little.
Also going to lean the bypass out another turn as that apparently affects mixture between 0-3/8 throttle.
Also going to lean the bypass out another turn as that apparently affects mixture between 0-3/8 throttle.
05-21-2018 | 07:11 PM
#66
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From: Seaford, VA
So - after a few more months and some conversations with some very knowledgeable people I now know that I had a Chinese knockoff Keinin carb but when I went back to the OEM carb the seat for the float needle was out of round. Evidently this is somewhat common in these Keihnin and they aren't replaceable - pressed in brass. I now have a new OEM airstryker on there courtesy of CarbWarehouse. Bike starts right up and doesn't smoke at all. I think it's still probably a little jumpy for a first bike but I'm going to go out and give it a little time - I just wonder if a 4-stroke would make a better starting bike.
05-21-2018 | 07:24 PM
#67
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From: Toledo Oh
Cheap experiment, If you can go a tooth bigger on the countershaft sprocket, that will be taller gearing and possibly a greater top speed but it will mellow it out a little bit, also ride a gear higher just dont lug the hell out of it.. you will be used to it and wanting more in no time....
