Honda Shadow Forums banner

Fuel mileage mods/tips for a 98 1100 Aero

5K views 11 replies 4 participants last post by  hat 
#1 ·
I'm new to this board. I recently purchased a 98 1100 aero with 20K on the clock. The bike has some sort of aftermarket pipes, baffled not straight pipes, so there is some restriction. The airbox is factory, with a stock filter ele. I do not know the status of the carbs, stock or modded. The PO said the bike would only do about 100 miles on a tank of fuel. before I start the process of getting this bike tuned, I thought I would ask for any suggestions from the resident experts. What settings and mods are proven to help fuel mileage? I'm not interested in power, as it has plenty now. thx.
 
#2 ·
The Aero[s are not notoriously good at burning fuel.

The same year Spirit (like mine - which is fully performance modified) will gets in the high 40mpg range with a solid the 45-46 range average.

Run a few tanks of fuel through it and get a good "Average" MPG so you have a good starting point. 100 miles on a tank tells you nothing. 30mpg on a tank tells you nothing. But 1000 miles and 30 gallons of gas is a solid MPG aaverage number to work against.

Lean out the idle mix screws until you get some decel popping in the exhaust.
Make sure the spark plugs have been replaced in the last 8k miles.
Check the spark plugs - ride at mid throttle for a while then hit the kill switch and coast off the road. Let the bike cool and perform a spark plug reading on each cylinder. See how they are running. Adjust accordingly.

About the best way to set the bike up is either go back to all stock exhaust and Jets (if equipped with aftermarket jetting). Or get a Jet kit and match it to your current exhaust. Dynojet is very good at providing you jetting to the installed exhaust, if you know what exhaust you are running.
 
#5 ·
hat said:
40mpg would be fine w/ me for now. what is the diff between it and the Spirit, is the Spirit a dual pin crank?
Yes, that is the difference.
FWIW - I have installed-
Samson Warlords Exahaust
Jetted using a Dynojet kit 175 mains, needle on the third clip
Dyna3000 Ign set to timing advance 4
Dyna Coils and a Dyna 8mm silicon ignition wires
NGK iridium spark plugs
K&N Air Filter.

Not everyone gets better mpg with these upgrades, but a lot has to do with how hard you run the bike, and I don't run it hard at all.
 
#7 ·
hat said:
so does the 4 deg. timing trick used for the 750's also apply to the 1100's?
Yes it is part of the dyna3000 package...but seriously I don't think it was worth the expense.

The jet kit and pipes is the best bang for the buck - everything else is probably only noticable on a dyno run. Crusiers just don't need this stuff - it was just fun to try - an expensive education if you will. :wink:
 
#8 ·
8) Welcome to the board HAT ! Enjoy the ride and don't worry about the fuel mileage. These tanks are difficult to fill consistantly as the filler neck prodrudes into the tank space. I have a 98 1100 Aero,V&H strightshots with quiet baffles,synced stock carbs, and stock air filter in box. As near as I can tell,, 40-42 is about my average, 120 ish per tank to reserve. Plenty good enough for me, I tend to ride abit hard, alot of my travel is 70+ mph and I apply plenty of throttle off the line. What I am saying, I do not ride for economy, but, that is just me. Still gets way more miles (and many more smiles) per gallon than my four wheel conveyence (read wagon). Be safe and enjoy the ride!!!!!! \\\ WIL /// 8)
 
#9 ·
hat said:
40mpg would be fine w/ me for now. what is the diff between it and the Spirit, is the Spirit a dual pin crank?
Another difference that could affect gas mileage is that the overall gearing on the Spirit is also about 15% higher than the Aero which accounts for some of the difference as well. Secondary reduction ratio on the Aero around .939 (31/33) while the Spirit is .806 (29/36).

I don't have the figures in front of me right now but I believe the Spirit may also be around 75 lbs. lighter in weight.

With your set up, I bet your Aero sounds wonderful! IMHO those single crankpin 1100s do sound great. 8)

And, Welcome to the forum!
Dave
 
#10 ·
:? It's odd how they do things sometimes? Why would the Spirit have taller gearing? As far as the fuel tank neck, I can see the liner/tube. Keeps splashback down, but why not a vent hole or two to allow filling the thing up? Oh, well, it's still a great bike. Needs a little attention, the PO was good about changing the oil, but not much else it seems. That'll give me something to play with this winter.
 
#11 ·
hat said:
:? It's odd how they do things sometimes? Why would the Spirit have taller gearing?
In the October 2003 Cycle World, they describe how the improvements to the 2004 Sportster (rubber mounted engine, stiffer frame) added about 50 pounds to the weight. Harley shortened the gearing on both the 883 and 1200 Sportsters to make sure the added weight didn't take away any performance gains.

My guess is that in 1995 when Honda came out with the 1100 ACE, it weighed more than the Spirit and also I've heard the single crank pin engine in the ACE may not have been put out as much power as the dual crankpin Spirit, so Honda lowered the gearing on the ACE to increase its performance. Here is a comparison of the 1999 Aero and Spirit and it does look like close to 70 pounds difference in weight which could have contributed to the gearing difference to compensate.

http://www.powersportsnetwork.com/e...le2=131&year1=1999&mfg1=1&vehicle1=134&go2=Go

Dave
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top