Going broke.....
#22
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Originally posted by: DuneRider650
160 main!!! seems like that would be going the opposite way for gaining hp...??
Originally posted by: atvaddict01
Stock jetting is 165 main needle on the 3rd.
When i got my hmf i was told to go with a 175 main and needle on the 4th.Way to rich.
I am now at 160 main and needle on the 3rd.I still have color on the plugs but it runs
great.
Stock jetting is 165 main needle on the 3rd.
When i got my hmf i was told to go with a 175 main and needle on the 4th.Way to rich.
I am now at 160 main and needle on the 3rd.I still have color on the plugs but it runs
great.
don't trust plug readings on a DS650. If you can read them accurately, you are alot better than me! The dual plug system and the fact the ignition fires every revolution (not just compression stroke) keeps the plugs white and clean - you have to be really rich to get color on them - or at least that's been my experience.
222
#23
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I agree with 222
Understand. . . the higher the flow (in this case velocity through your carb) the lower the atmospheric pressure is inside your carb.
Since you put a bigger exhaust / open end-cap you have decreased restriction in the exhaust thus increasing flow of air in your engine and through your carb. . .
So. . . now you have higher velocity through your carb.
So, with reduced pressure in the body of the carb and constant (relatively) pressure on the fuel, your carb is essentially sucking harder on the straw and drawing more fuel into its thirsty self (Yum Yum. . . engine likey fuel).
So, you sometimes actually have to go to a smaller jet (straw) to get proper jetting.
This is the same information engineers use to design wings for airplanes and keeps these planes in the air. Off topic but, wings are shaped to get a faster air flow over the top of the wing to create a differential pressure causing lift (and that's all I know about airplanes!)
Understand. . . the higher the flow (in this case velocity through your carb) the lower the atmospheric pressure is inside your carb.
Since you put a bigger exhaust / open end-cap you have decreased restriction in the exhaust thus increasing flow of air in your engine and through your carb. . .
So. . . now you have higher velocity through your carb.
So, with reduced pressure in the body of the carb and constant (relatively) pressure on the fuel, your carb is essentially sucking harder on the straw and drawing more fuel into its thirsty self (Yum Yum. . . engine likey fuel).
So, you sometimes actually have to go to a smaller jet (straw) to get proper jetting.
This is the same information engineers use to design wings for airplanes and keeps these planes in the air. Off topic but, wings are shaped to get a faster air flow over the top of the wing to create a differential pressure causing lift (and that's all I know about airplanes!)
#25
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Originally posted by: DuneMe
I agree with 222
Understand. . . the higher the flow (in this case velocity through your carb) the lower the atmospheric pressure is inside your carb.
Since you put a bigger exhaust / open end-cap you have decreased restriction in the exhaust thus increasing flow of air in your engine and through your carb. . .
So. . . now you have higher velocity through your carb.
So, with reduced pressure in the body of the carb and constant (relatively) pressure on the fuel, your carb is essentially sucking harder on the straw and drawing more fuel into its thirsty self (Yum Yum. . . engine likey fuel).
So, you sometimes actually have to go to a smaller jet (straw) to get proper jetting.
This is the same information engineers use to design wings for airplanes and keeps these planes in the air. Off topic but, wings are shaped to get a faster air flow over the top of the wing to create a differential pressure causing lift (and that's all I know about airplanes!)
I agree with 222
Understand. . . the higher the flow (in this case velocity through your carb) the lower the atmospheric pressure is inside your carb.
Since you put a bigger exhaust / open end-cap you have decreased restriction in the exhaust thus increasing flow of air in your engine and through your carb. . .
So. . . now you have higher velocity through your carb.
So, with reduced pressure in the body of the carb and constant (relatively) pressure on the fuel, your carb is essentially sucking harder on the straw and drawing more fuel into its thirsty self (Yum Yum. . . engine likey fuel).
So, you sometimes actually have to go to a smaller jet (straw) to get proper jetting.
This is the same information engineers use to design wings for airplanes and keeps these planes in the air. Off topic but, wings are shaped to get a faster air flow over the top of the wing to create a differential pressure causing lift (and that's all I know about airplanes!)
...and, you just explained why the metering rod on a Lectron looks like it does!
222
#26
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[img]i/expressions/face-icon-small-confused.gif[/img] If you say so [img]i/expressions/face-icon-small-confused.gif[/img] [img]i/expressions/face-icon-small-confused.gif[/img] [img]i/expressions/face-icon-small-confused.gif[/img]
I'ld like to run one of those on my Bike to see how it does vs. the FCR's but, I can't justify the $$ just to try something out. I know the FCR's can do the job and I really wonder at the 4500' ASL elevation I usually run at, if the FCR's aren't a better carb. I know the only way to tell this is to get one and try it but, my focu$ is NOT on spending more money right now. So, for now I guess I'll have to settle for being a little slower.
I've actually got a set of dual Lectron 41's I should send you to re-work for gas. They've been set-up for Alky and nave a few parts missiing. I just don't have the time to get them fixed up.
I've actually got an extra tranny and some other parts that I hear you guys may be interested in as cores to speed up your turn-a-round to customers too. One of these days when I have some time I'll have to get with you. . .
I'ld like to run one of those on my Bike to see how it does vs. the FCR's but, I can't justify the $$ just to try something out. I know the FCR's can do the job and I really wonder at the 4500' ASL elevation I usually run at, if the FCR's aren't a better carb. I know the only way to tell this is to get one and try it but, my focu$ is NOT on spending more money right now. So, for now I guess I'll have to settle for being a little slower.
I've actually got a set of dual Lectron 41's I should send you to re-work for gas. They've been set-up for Alky and nave a few parts missiing. I just don't have the time to get them fixed up.
I've actually got an extra tranny and some other parts that I hear you guys may be interested in as cores to speed up your turn-a-round to customers too. One of these days when I have some time I'll have to get with you. . .
#27
#28
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Well i just got back from taking out the 173.5 main and putting in the stock 165 main, and was very surprised to see my top end was better...hmmm. Pretty sure you guys were right on this one...against the wind up hill on the highway i pulled my rev limiter and thats 80mph as before with the big jet i was having to tuck down with no wind and a super long stretch to pull it.....think i lost a tiny bit of mid tho......................I will test her out a little later tonight to really see if it made that much difference, there were to many factors this time with all the wind out there.
#29
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Originally posted by: DuneRider650
Well i just got back from taking out the 173.5 main and putting in the stock 165 main, and was very surprised to see my top end was better...hmmm. Pretty sure you guys were right on this one...against the wind up hill on the highway i pulled my rev limiter and thats 80mph as before with the big jet i was having to tuck down with no wind and a super long stretch to pull it.....think i lost a tiny bit of mid tho......................I will test her out a little later tonight to really see if it made that much difference, there were to many factors this time with all the wind out there.
Well i just got back from taking out the 173.5 main and putting in the stock 165 main, and was very surprised to see my top end was better...hmmm. Pretty sure you guys were right on this one...against the wind up hill on the highway i pulled my rev limiter and thats 80mph as before with the big jet i was having to tuck down with no wind and a super long stretch to pull it.....think i lost a tiny bit of mid tho......................I will test her out a little later tonight to really see if it made that much difference, there were to many factors this time with all the wind out there.
#30