Better MPG with my coils replaced

[Leathel]

Previously I have needed to regas at 150 miles  as it starts to sputter before hitting reserve (my bike has a shorter reserve pipe)

 I was getting 37-45mpg depending on how I rode

The last few tanks I have been surprised that the tank refill amounts... the latest I did 119 miles and the tank was full to the brim with 9.8 liters...55mpg (I have punched a hole in the filler spout to aid total fills) so in theory I should get 200+ miles on a tank

That 55mpg was done on mostly twisty roads and on a low tire (28psi, checked when I got back as it didn't feel right) so I look forward to trying to do better

 The only change was swapping the std coils for the larger 30510-MM8-003 coils (I had some of my old bike) At least one of my coils was faulty when cold so I guess better MPG is to expected cold but I didn't expect that much change as you didn't felt any loss of power when warm??

[WintrSol]

Um ... 9.8 liters is 2.6 gallons, so 45.8mpg, not 55mpg.

[pokrovsky]

Must be British gallons I reckon

[Leathel]

Um ... 9.8 liters is 2.6 gallons, so 45.8mpg, not 55mpg.

yeah sorry it was a brit calculator, meant to link that.

[Jims99]

I hit reserve on the tourer at 120-125 miles. If I run over 70-75 it drops around 110-115. Running over 80 and reserve is hit between 95-100 miles. Bike runs perfect and can’t seem to get it any better. Don’t really care, just keep it at 70-75 when going long distance. The hotter spark will give you slightly more power with slightly less throttle. I can see that helping with mpg.

[f-Stop]

That's exemplary fuel mileage!  I'm in line with Jims99/00 which translates to about 32mpg (US) overall...that's with the wind behind me and runnin' downhill.

So...curious about those coils.  Which bike did you get them off of?  As far as I can tell, 30510-KT7-023 is the coil used on all years and models of GL1500C Valkyries.  The 305-MM8-003 coil is still available, but not necessarily used on the Valkyrie.  (Maybe it's a stateside thing?). Are those coils the same size as your old stock coils and were they basically plug-n-play?

Also, are you using the standard spark plugs?  Spark plug wires?

Last question...do you have a 6 degree trigger wheel installed?

 

[h13man]

All original 99' parts except custom wires, constant 35 mpg. but staying under 3000 rpm w/o a heavy hand I can achieve 44 mpg. using Shell w/o ethanol. Shell always netted me 2 mpg. extra on three different bikes now but Shell is at out of the way locations in my area thus any non ethanol locations with high volume turn over works for me. Usually do fill ups at preselected places while out riding. Excel Co-Op/Co Alliance is local and has scattered locations throughout the state.

[WintrSol]

So, for us using US gallons, divide your mpg by 0.8327 to get it in UK units, to compare to the OP's numbers. So 35mpg (US) equals 42mpg (UK).

[Leathel]

That's exemplary fuel mileage!  I'm in line with Jims99/00 which translates to about 32mpg (US) overall...that's with the wind behind me and runnin' downhill.

So...curious about those coils.  Which bike did you get them off of?  As far as I can tell, 30510-KT7-023 is the coil used on all years and models of GL1500C Valkyries.  The 305-MM8-003 coil is still available, but not necessarily used on the Valkyrie.  (Maybe it's a stateside thing?). Are those coils the same size as your old stock coils and were they basically plug-n-play?

Also, are you using the standard spark plugs?  Spark plug wires?

Last question...do you have a 6 degree trigger wheel installed?

 

Std plugs std trigger wheel but this is a UK bike and they have a Throttle Position sensor that the ECM uses for timing

It came with smaller 78 jets and restricted intake and exhaust........ but now has 100 jets, removed the smaller UK pigtails and punched the baffles (yes I know some hate molesting oem pipes) and modded the intake but it consistently used more fuel than I expected until now. We have a 100km speed limit so no long high speed runs but i dont idle along either....

[98valk]

That's exemplary fuel mileage!  I'm in line with Jims99/00 which translates to about 32mpg (US) overall...that's with the wind behind me and runnin' downhill.

So...curious about those coils.  Which bike did you get them off of?  As far as I can tell, 30510-KT7-023 is the coil used on all years and models of GL1500C Valkyries.  The 305-MM8-003 coil is still available, but not necessarily used on the Valkyrie.  (Maybe it's a stateside thing?). Are those coils the same size as your old stock coils and were they basically plug-n-play?

Also, are you using the standard spark plugs?  Spark plug wires?

Last question...do you have a 6 degree trigger wheel installed?

 

from my post older thread, I originally did this over 10 yrs ago, posted about it, zero responses.

Almost a direct replacement. They are the OEM coils from a CBR1100XX (blackbird), ST1300, 2000 sabre and all 2001 and newer 1100 shadows. The VTX uses this coil on the forward cylinder and uses the same numbered coil (MP10) for the rear coil but carries a different part number and is green in color. From a VTX site I was told same ohm ratings why different color, nobody knew.  All others are black. They will be identified with MP10 on the coil, the Valkyrie's are MP8.
This coil reads 2.4 ohms @ 60 degrees F whereas the stock Valkyrie coils read 2.9 ohms. This is a 0.5 ohm difference which will provide higher voltage to the plug. The stock Valkyrie coils are also used on the ST1100, CBR900RR, CB919, GW1500 and the older shadows.
Installation of the side coil is a direct replacement. The two under the tank will require longer bolts and the forward coil's bolt holes must be moved 1/2 inch forward by making an adapter bracket.

http://www.valkyrieforum.com/bbs/index.php/topic,2318.0.html

[Leathel]

Quite a few tank fulls later......... and I am still using less fuel, less throttle movement needed to accelerate swiftly and full throttle from 2k rpm gives good even power right through. I used to use 12 plus liters per 100 miles (fuel sold per liter here) but now its sub 10 liters 100% of the time even on tight twisty roads pushing it.. its added at a guess 50 miles to my range.....only recent changes were going from Avon Cobra to Chrome on the rear and the coils.

 Definitely starts quicker and idles better cold so the tire not at play there

 I must get back into taking pics and videos..... Just got out of the habit of taking pics and putting the camera on. I did take this last week in front of an old overgrown shed last week

[98valk]

That's exemplary fuel mileage!  I'm in line with Jims99/00 which translates to about 32mpg (US) overall...that's with the wind behind me and runnin' downhill.

So...curious about those coils.  Which bike did you get them off of?  As far as I can tell, 30510-KT7-023 is the coil used on all years and models of GL1500C Valkyries.  The 305-MM8-003 coil is still available, but not necessarily used on the Valkyrie.  (Maybe it's a stateside thing?). Are those coils the same size as your old stock coils and were they basically plug-n-play?

Also, are you using the standard spark plugs?  Spark plug wires?

Last question...do you have a 6 degree trigger wheel installed?

 

Std plugs std trigger wheel but this is a UK bike and they have a Throttle Position sensor that the ECM uses for timing

It came with smaller 78 jets and restricted intake and exhaust........ but now has 100 jets, removed the smaller UK pigtails and punched the baffles (yes I know some hate molesting oem pipes) and modded the intake but it consistently used more fuel than I expected until now. We have a 100km speed limit so no long high speed runs but i dont idle along either....

have u ever found what the ICM curves are with the throttle Position sensor that the ECM uses for timing?

[Leathel]

That's exemplary fuel mileage!  I'm in line with Jims99/00 which translates to about 32mpg (US) overall...that's with the wind behind me and runnin' downhill.

So...curious about those coils.  Which bike did you get them off of?  As far as I can tell, 30510-KT7-023 is the coil used on all years and models of GL1500C Valkyries.  The 305-MM8-003 coil is still available, but not necessarily used on the Valkyrie.  (Maybe it's a stateside thing?). Are those coils the same size as your old stock coils and were they basically plug-n-play?

Also, are you using the standard spark plugs?  Spark plug wires?

Last question...do you have a 6 degree trigger wheel installed?

 

Std plugs std trigger wheel but this is a UK bike and they have a Throttle Position sensor that the ECM uses for timing

It came with smaller 78 jets and restricted intake and exhaust........ but now has 100 jets, removed the smaller UK pigtails and punched the baffles (yes I know some hate molesting oem pipes) and modded the intake but it consistently used more fuel than I expected until now. We have a 100km speed limit so no long high speed runs but i dont idle along either....

have u ever found what the ICM curves are with the throttle Position sensor that the ECM uses for timing?

I would love to find out, also double check fuel mix and see what HP/torque is but that means going to a good bike shop and there are none near me...I should research just who is set up for it that will do it (Only shop I know has it is factory HD shop, HD only)

[Madmike]

Um ... 9.8 liters is 2.6 gallons, so 45.8mpg, not 55mpg.

Difference between Imperial Gallons and US gallons.  US gallon is smaller.  Imperial gallon is 4.54 Liters, US gallon is something like 3.78L (???) per gallon.