Fuel Mileage

I will. Trust me guys, I want to keep the Rocket. Nothing else has ever given me the thrill this thing does when I hammer down on the throttle. My problem is I can't afford three bikes right now.

I plan to bring it to the dealer for them to upload the tune again. They are cool and let me watch so I will make sure they put #54 in. I run with the Power Commander which destroyed the fuel mileage. I was getting about 35mpg before. Without the PC though my bike backfires like nuts.

Without the PC though my bike backfires like nuts.

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I think eliminating the back fire issue is overrated. Especially given the decrease in gas mileage. All bikes backfire, you just don't hear it until you alter stock silencers.

My D&D's backfire but hardly to the point of doing something as drastic as releasing raw fuel during decel. My two cents.

Hondax, How do you like the D&D mufflers? and what tune did they require? I've been thinking of going with that set up. You sure can't beat the price.

Most stock RIII's seem to get around 33-35 mpg... but there are many things that can effect milage... speed, acceleration, reving, stop & go vs highway miles etc...

But it is a pipe dream if you think you can do performance mods on the bike and still get the same kind of mileage. There are 3 variables to an internal combustion motor. Air in, fuel in and exhaust out. Those three variables need to be kept in balance for optimum performance. That is what the EFI tunes do! If you increase the air in (K&N or other air box mods) and/or decrease the exhaust back pressure, exhaust out, (cat by-pass and / or aftermarket pipe) then you must increase the fuel delivery (efi tunes and / or PCIII). And when you increase the fuel delivery, guess what? Your mileage is gonna go down. Now add to that - with the increased HP you are gonna be riding more aggressively and with the increased sound... you're gonna be reving it more! Bingo - there goes the gas mileage.

So if you are getting "normal" mileage - 33-35 mpg... those performance mods are going reduce your gas mileage and it's reasonable to expect that it might drop as low as into the 20's.

I don't know about any of you... but I did not buy this bike for it's gas mileage!

Hondax, How do you like the D&D mufflers? and what tune did they require? I've been thinking of going with that set up. You sure can't beat the price.

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Hi Tx, You have to ask yourself a question.....can I live without the "stock" muffler look cuz the D&D are 3 in 2's? Here's a link to a D&D dyno: http://www.newr3.com/html/d_and_d_exhaust.html

Yes the price is very reasonable. Some dealers are putting them on new bikes to give an improved sound and a good clean jump in performance without changing the price to obscenely.

My D&D's were on the bike when I bought it and had the option of replacing with stock set-up but to me that was no option. I left it up to my wife in reality, when i ask her if the D&D's seemed loud. She thought they were fine so they stayed on.

I wear ear plugs when i ride so I won't go deaf from the wind noise but I can hear the D&D's as well as the motor sounds. The silencers do not overpower other sounds. Correction, the D&D's do not overpower other sounds at idle and at speed, but DEFINITELY overpower everything during moderate to full acceleration.

A Triumph aftermarket silencer tune was used but my dealer didn't know which one and the bike ran so well i didn't pursue it further. Your dealer should know exactly what tune to use.

It just came to me why you like the D&D's,......their made in Texas......HA HA!!!

I didn't buy the bike for gas mileage either but I guess my personal finances have me in a different boat than some of you. Apparently since I am asking myself how much does it cost to maintain this bike I am starting to wonder if I can really afford it.

I am not looking for pity fella's so don't worry, this isn't a woowaa's me post. The cost of living in my area is growing faster than my salary growth (I guess who isn't in the same boat). I am having to consider some really hard decisions about everything, not just the Rocket .

vonbonds said:

I didn't buy the bike for gas mileage either but I guess my personal finances have me in a different boat than some of you. Apparently since I am asking myself how much does it cost to maintain this bike I am starting to wonder if I can really afford it.

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Oh I really wasn't posting to you... or anyone specific. It just seems that some think they can tinker with engine performance mods and they expect the gas mileage to remain a constant. It won't.

By all means... whatever you ride is a matter of personal choice all the way.

As far as mods go I have the TORs and cat-by-pass pipe. Nothing else besides the PC to remove the decel popping. I am running the zero map too. I have tweaked it much farther below to get better fuel economy but the bike ran like crap, very weak. I went back to the zero map because why ride around on a wounded animal. This is a beast and should have the power of one!

I think you have some sort of malfunction, with the mods you have you shouldn't be in the 20's. In fact... as poor as your mileage is, I would almost think that you would see lots of black smoke from your exhaust indicating a very rich mixture. The tips of your exhaust should be heavily coated in carbon. I know for a fact Triumph dealers have an exhaust gas analizer that should confirm a very rich mixture.

You know what you should try first though??? I would check the accuracy of your odometer against mile markers. If you go an actual 10 miles but your odometer only shows 7 thats is going to mess up your calculation for MPG big time. This happens with cars more than you might think... the two main culprits being the speedo head (the odometer itself is malfunctioning) and the vehicle speed sensor and/or its wiring harness. I wouldn't measure it against a GPS. Or is that how you are doing it...... Oh Oh.... The GPS may be spot on and everyone knows the speedo on Triumphs are about 10% off, and so is the odometer probably. Maybe we are all getting 28 MPG in reality but our out of wack speedos are just putting a rosy tint on things...

Don't bust my bubble, Tomo!