Question for carb guys
#1
05-12-2007, 12:49 AM
Question for carb guys
Last year I had an indie work on my 05 carbureted low rider. He has a great rep in working w/ sport bikes and as it was explained to me by someone who had their sport bike I4 modified by him contended that they were much more complicated to work on than a v-twin and that carb work is similar across engines.
[align=center]So let's bury the hatchet, I may have made a mistake using this guy. [/align]
Here's what we put on the bike during his "tune." Rineharts, 44CV S/E carb (230 main jet was needed to bring a/f down according to indie) and Crane Cams fully adjustable ignition module (he advanced the timing on the rear cylinder from my understanding).
According to his dyno the HP was around 70.6 w/ rainy and warm weather. The indie contended that the a/f ratio was 13.4 which from what I have read seems a little rich. After riding for most of last summer with others behind me commenting how bad it smells, black puffs of smoke at every throttle twist and my gas mileage royally sucking, I believe that is correct info. I don't expect factory gas mileage, but 31 mpg is pretty far off the mark.
Fast forward to today. I am taking my bike to the stealer as they recently got a dyno of their own right around the new year. They are going to dyno the thing and we'll see what they come up with. In an attempt to be armed with some knowledge this time, can someone offer an opinion as to what might need to occur with the info on the tune I provided? What would you suggest before I take it in? The bike runs fine, just rich.
Thanks
[align=center]So let's bury the hatchet, I may have made a mistake using this guy. [/align]
Here's what we put on the bike during his "tune." Rineharts, 44CV S/E carb (230 main jet was needed to bring a/f down according to indie) and Crane Cams fully adjustable ignition module (he advanced the timing on the rear cylinder from my understanding).
According to his dyno the HP was around 70.6 w/ rainy and warm weather. The indie contended that the a/f ratio was 13.4 which from what I have read seems a little rich. After riding for most of last summer with others behind me commenting how bad it smells, black puffs of smoke at every throttle twist and my gas mileage royally sucking, I believe that is correct info. I don't expect factory gas mileage, but 31 mpg is pretty far off the mark.
Fast forward to today. I am taking my bike to the stealer as they recently got a dyno of their own right around the new year. They are going to dyno the thing and we'll see what they come up with. In an attempt to be armed with some knowledge this time, can someone offer an opinion as to what might need to occur with the info on the tune I provided? What would you suggest before I take it in? The bike runs fine, just rich.
Thanks
#2
05-12-2007, 03:43 AM
RE: Question for carb guys
ORIGINAL: Dynamite
Last year I had an indie work on my 05 carbureted low rider. He has a great rep in working w/ sport bikes and as it was explained to me by someone who had their sport bike I4 modified by him contended that they were much more complicated to work on than a v-twin and that carb work is similar across engines.
[align=center]So let's bury the hatchet, I may have made a mistake using this guy. [/align]
Here's what we put on the bike during his "tune." Rineharts, 44CV S/E carb (230 main jet was needed to bring a/f down according to indie) and Crane Cams fully adjustable ignition module (he advanced the timing on the rear cylinder from my understanding).
According to his dyno the HP was around 70.6 w/ rainy and warm weather. The indie contended that the a/f ratio was 13.4 which from what I have read seems a little rich. After riding for most of last summer with others behind me commenting how bad it smells, black puffs of smoke at every throttle twist and my gas mileage royally sucking, I believe that is correct info. I don't expect factory gas mileage, but 31 mpg is pretty far off the mark.
Fast forward to today. I am taking my bike to the stealer as they recently got a dyno of their own right around the new year. They are going to dyno the thing and we'll see what they come up with. In an attempt to be armed with some knowledge this time, can someone offer an opinion as to what might need to occur with the info on the tune I provided? What would you suggest before I take it in? The bike runs fine, just rich.
Thanks
Last year I had an indie work on my 05 carbureted low rider. He has a great rep in working w/ sport bikes and as it was explained to me by someone who had their sport bike I4 modified by him contended that they were much more complicated to work on than a v-twin and that carb work is similar across engines.
[align=center]So let's bury the hatchet, I may have made a mistake using this guy. [/align]
Here's what we put on the bike during his "tune." Rineharts, 44CV S/E carb (230 main jet was needed to bring a/f down according to indie) and Crane Cams fully adjustable ignition module (he advanced the timing on the rear cylinder from my understanding).
According to his dyno the HP was around 70.6 w/ rainy and warm weather. The indie contended that the a/f ratio was 13.4 which from what I have read seems a little rich. After riding for most of last summer with others behind me commenting how bad it smells, black puffs of smoke at every throttle twist and my gas mileage royally sucking, I believe that is correct info. I don't expect factory gas mileage, but 31 mpg is pretty far off the mark.
Fast forward to today. I am taking my bike to the stealer as they recently got a dyno of their own right around the new year. They are going to dyno the thing and we'll see what they come up with. In an attempt to be armed with some knowledge this time, can someone offer an opinion as to what might need to occur with the info on the tune I provided? What would you suggest before I take it in? The bike runs fine, just rich.
Thanks
#3
05-12-2007, 09:58 AM
#4
05-12-2007, 10:12 AM
Outstanding HDF Member
#6
05-12-2007, 11:10 AM
RE: Question for carb guys
The jet being way too big was my thought. The indie said the a/f was too high with the 225 that comes in the 44CV carb from the factory.
Thanks for the feedback...definately some good info.
As for the the carb being too big, I guess I'll just have to plan that 95 / 103 ci. conversion.
Thanks for the feedback...definately some good info.
As for the the carb being too big, I guess I'll just have to plan that 95 / 103 ci. conversion.
#7
05-12-2007, 11:22 AM
RE: Question for carb guys
ORIGINAL: Dynamite
The jet being way too big was my thought. The indie said the a/f was too high with the 225 that comes in the 44CV carb from the factory.
Thanks for the feedback...definately some good info.
As for the the carb being too big, I guess I'll just have to plan that 95 / 103 ci. conversion.
The jet being way too big was my thought. The indie said the a/f was too high with the 225 that comes in the 44CV carb from the factory.
Thanks for the feedback...definately some good info.
As for the the carb being too big, I guess I'll just have to plan that 95 / 103 ci. conversion.
Also the carb comes with a 220 jet and a L needle out of the box....the jets only come in full sizes ie 200, 210, 220, 230, 240, 250.
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#8
05-12-2007, 11:59 AM
RE: Question for carb guys
ORIGINAL: Doc 1
The SE44mm C/V carb is a little big if your looking for low end throttle response, it will work and it will give you more power up high but your not riding your bike all day long in the higher rpms.....if your going 70 mph your bike is at 3000rpm.
Also the carb comes with a 220 jet and a L needle out of the box....the jets only come in full sizes ie 200, 210, 220, 230, 240, 250.
The SE44mm C/V carb is a little big if your looking for low end throttle response, it will work and it will give you more power up high but your not riding your bike all day long in the higher rpms.....if your going 70 mph your bike is at 3000rpm.
Also the carb comes with a 220 jet and a L needle out of the box....the jets only come in full sizes ie 200, 210, 220, 230, 240, 250.
Also, seat of the pants says it has much better response off the line that previously. You seem to have a wealth of knowledge on this subject as I have read some of your other posts.
#9
05-12-2007, 12:32 PM
RE: Question for carb guys
ORIGINAL: Dynamite
You must be correct, however I thought S/E offered a 228 or some odd size when I checked? I will be curious to see what the tq number is and where it comes in as there was some type of "bad connection" when the indie dynoed my bike and the tq. shows 156.4 (Right). With the help of an engineer friend and some mild assumptions we determined a mathmatical equation to put the tq. in actual numbers (we'll skip those details) but the tq. adjusted # is around 74. In any case the hp peaks around 2700 RPM. HP and TQ intersect at about 2525 RPM. Could you explain why this setup would offer better throttle response in the high end? What could I do to take more advantage of the 44cv? I bought it so I might as well use it.
Also, seat of the pants says it has much better response off the line that previously. You seem to have a wealth of knowledge on this subject as I have read some of your other posts.
ORIGINAL: Doc 1
The SE44mm C/V carb is a little big if your looking for low end throttle response, it will work and it will give you more power up high but your not riding your bike all day long in the higher rpms.....if your going 70 mph your bike is at 3000rpm.
Also the carb comes with a 220 jet and a L needle out of the box....the jets only come in full sizes ie 200, 210, 220, 230, 240, 250.
The SE44mm C/V carb is a little big if your looking for low end throttle response, it will work and it will give you more power up high but your not riding your bike all day long in the higher rpms.....if your going 70 mph your bike is at 3000rpm.
Also the carb comes with a 220 jet and a L needle out of the box....the jets only come in full sizes ie 200, 210, 220, 230, 240, 250.
Also, seat of the pants says it has much better response off the line that previously. You seem to have a wealth of knowledge on this subject as I have read some of your other posts.
A larger bore whether it is in a port or throttle body looses velocity over a smaller bore...when the velocity falls the cylinder fill deminishes (volumetric effiency) so power will will drop till the rpms are higher which creates a higher velocity (makes the air move faster) so power is gained in the higher rpms. Now if you had a larger displacment like a 95' or 103' per say the larger displacment will cause more velocity so the larger carb will work well from bottom end to top end. Bore size is all revelant to displacment. If you had a 103' motor and put on a 40mm carb it would have awesome lowebnd throttle response but the smaller bore would restrict the flow on top end and it wiuld suffer....sorry to say but there is no free lunch building motors, you have to give some where to gain some where.
#10
05-12-2007, 12:38 PM
RE: Question for carb guys
ORIGINAL: Doc 1
Ask for the fuel graph, the pilot should be 14.2:1 to 14.4:1....needle should be around 13.5:1 and main jet should be from 13.2:1 to 12.8:1 thats asclose as your going to get to fuel for econmy....and power. Good Luck
Ask for the fuel graph, the pilot should be 14.2:1 to 14.4:1....needle should be around 13.5:1 and main jet should be from 13.2:1 to 12.8:1 thats asclose as your going to get to fuel for econmy....and power. Good Luck