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Discussion Starter #1
I've mentioned in another thread that I'm going to hookup a MPGuino fuel consumption computer to the CBR. The MPGuino is an open source project and is available for order ($55) over on the ecomodder forum.

It's a simple 4 wire hook up. One to 12v unswitched power (more about this later), one to ground, one to the fuel injector signal and finally, one to a Vehicle Speed Sensor.

After that, you must calibrate it for the vehicle it's been installed on. I keep close track of my consumption so this shouldn't be to difficult at all.

Now, all that being said, the MPGuino arrived yesterday. I'm going to hook it up to see if it'll actually work on the CBR. If so, I'll fabricate up a weatherproof enclosure for it (it doesn't come in a case) and a suitable mount for it.

Then we really see where and how to ride the CBR for max gas mileage.

Stay tuned if your interested. Pics to follow.
 

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Discussion Starter #5 (Edited)
Very affordable. Will be cool if you can get it dialed in. Even if it is not exactly accurate to the final number, it will still be useful relative to it's self as a guide to better hypermiling technique.
Exactly correct Sendler. It's easy to determine these things on a car, low revving and torquey. On a bike with a relativey weak engine, it's another thing entirely.

However, I'm more interested in gph figures at various rpm's/gears outside of technique, to determine optimum shift points and the like.

Post up the data points/circumstances your most interested in seeing, and, if the unit works on the Honda, I'll get them posted up. Of course, all these figures will be for my bike, but they should be roughly translatable to other CBR's.

Unfortunately, the test install won't be today. It's feckin' snowing in Northern Ontario (sorry Tom :) today.

Just to establish some ground rules, I will not be posting mpg figures. I will be posting up fuel usage figures (injector timing). MPG will be a result of this figure. This will eliminate technique. No tucking. Sorry, but I refuse to accommodate a vehicle, the vehicle must accommodate me. So, normal riding position. All posted data will be done on level ground and averaged across at least 4 2 way runs to average out the affect of wind, slope etc.

Additionally I'll remove my 2 Bros and go back to the stock pipe to more accurately reflect the performance/weight differences so it applies to as broad a base of bikes as possible. I'll also remove my tailbag to eliminate that as an aerodynamic variable.

My bike is running about 2700Km right now so we can safely assume it's reasonably broken in. I'll continue to use standard dino oil. I'll also try to video both the units display and tachometer/speedometer so that you can verify my results.

I'm going to run over Radio Shack/The Source today for a project box to mount the unit in. I need to go back and research a RAM mount. Hopefully on the steering nut.

This should be some fun.
 

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Bother

I don't know if you need to bother stripping your bike from the normal set up that you ride. Again, the absolute numbers will change with the addition of a trunk ect. but the relative comparison between shifting at 4000 vs 7000 will be valid with or without any added drag. Changing the pipe in and out will change things but could become confusing with the added variable of ECU adaptation.
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Ps. Laying on the tank is my normal riding position.:)
Exactly correct Sendler. It's easy to determine these things on a car, low revving and torquey. On a bike with a relativey weak engine, it's another thing entirely.

However, I'm more interested in gph figures at various rpm's/gears outside of technique, to determine optimum shift points and the like.

Post up the data points/circumstances your most interested in seeing, and, if the unit works on the Honda, I'll get them posted up. Of course, all these figures will be for my bike, but they should be roughly translatable to other CBR's.

Unfortunately, the test install won't be today. It's feckin' snowing in Northern Ontario (sorry Tom :) today.

Just to establish some ground rules, I will not be posting mpg figures. I will be posting up fuel usage figures (injector timing). MPG will be a result of this figure. This will eliminate technique. No tucking. Sorry, but I refuse to accommodate a vehicle, the vehicle must accommodate me. So, normal riding position. All posted data will be done on level ground and averaged across at least 4 2 way runs to average out the affect of wind, slope etc.

Additionally I'll remove my 2 Bros and go back to the stock pipe to more accurately reflect the performance/weight differences so it applies to as broad a base of bikes as possible. I'll also remove my tailbag to eliminate that as an aerodynamic variable.

My bike is running about 2700Km right now so we can safely assume it's reasonably broken in. I'll continue to use standard dino oil. I'll also try to video both the units display and tachometer/speedometer so that you can verify my results.

I'm going to run over Radio Shack/The Source today for a project box to mount the unit in. I need to go back and research a RAM mount. Hopefully on the steering nut.

This should be some fun.
 

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snow

Unfortunately, the test install won't be today. It's feckin' snowing in Northern Ontario (sorry Tom :) today.
Not snowing here yet but forecasts are for overnight lows in the 30's (sorry, 2C) next week. But sunny for a change. I will ride anyway. Another reason why I like to lay on the tank. Besides being very comfortable and relaxed, I get zero wind chill on my neck. I need some warmer gloves though and will probably order the Rev'it Bastion today.
 

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Discussion Starter #8
I don't know if you need to bother stripping your bike from the normal set up that you ride. Again, the absolute numbers will change with the addition of a trunk ect. but the relative comparison between shifting at 4000 vs 7000 will be valid with or without any added drag. Changing the pipe in and out will change things but could become confusing with the added variable of ECU adaptation.
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Ps. Laying on the tank is my normal riding position.:)
Agreed about the relativity, but then the question will always remain, "What about a stock bike?" For sure the pipe/ECU will have affect so they will be swapped out (Probably do it at the same time as the MPGuino test run, only takes 5 minutes). Same thing for the tailbag. If it's introducing aero load (or perhaps even improving it!) it won't be representative of a stock bike. The relativity factor is still there however.

As for laying on the tank, you ride your bike, I'll ride mine :D I know it makes a huge diff (I've done some coast down tests from hwy speeds). Any relative difference between the two styles remain.
 

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Discussion Starter #9 (Edited)
Okay, so after a bunch of running around back and forth to Radio Shack for a project box I've finally got the unit mocked up. I need only to silicon it in place once I'm satisfied things will be permanent.

First snafu. I didn't measure the computer itself just went by what others have done on the Interwebs. They all used the 'small' project box. Picked one up, turns out the design has changed somewhat and the unit is slightly longer than it was at some other point in time. Wouldn't fit the small box.

I exchanged it for the only other box our local store had. Same basic size but 5x3x2 (approx). Their is a LOT of extra room in the box. Lets chalk it up to airflow.



I guess all those models I built as a kid paid off. Turned out pretty good. The unit isn't much bigger than the screen you can see. The 3 buttons on the top are switches for doing input into the computer. Wish they pointed down - just to make it more water resistant. I'll have to skin the inside of the switches to try to keep the water off.

Before I spend the bucks on a RAM mount setup (I'm going to end up buying one anyway) I'll velcro it in place to see if it'll actually work on the CBR.

Next step is to identify and tap into, both the proper injector wire and the VSS signal off the top of the crankcase. The only 2 other wires are for 12v and ground.

I've got a guy coming to look at my 94 Ninja tomorrow night (please buy it!) so I won't get the wiring done till at least Thurs or Friday. But at least some progress has been made.

I love my Dremel. But filing the last bit of box opening by hand was a pain in the ass!

Stay tuna'd.
 

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Neat project! Looks like you are getting close.

I see you are a member at Ecomodder.com also. Lots of interesting folks over there - some are totally hardcore mileage seekers.


Jay
 

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Discussion Starter #11
Neat project! Looks like you are getting close.

I see you are a member at Ecomodder.com also. Lots of interesting folks over there - some are totally hardcore mileage seekers.
Getting 100mpg is kind of addictive. But I'm not anywhere near as craz.. hardcore as a lot of those guys. More curious than anything.

I still haven't gotten around to wiring it up. It was just to nice this past weekend not to ride with the end of season so close. Their calling for rain the last half of the week which will give me time to get it wired up.

The unit ships with a telephone jack for a connector which obviously isn't rated for the heat, moisture and vibration on a bike so I'll have to rig up some sort of DIN plug for it. I want it easily removable as well.
 

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Did you ever get your MPGuino running? I'm going to enter the Green Grand Prix and will be using some engine off pulse and glide (and hoping it doesn't lock up my transmission). I am assuming the most efficient engine range would be to pulse up at 80% throttle at rpms around the first torque peak of 6,000rpm. Contrary to hypermiling intuition, this will mean running up and down from 45 to 55mph in 4th gear for two hours rather than cruising along at 4,700 in 6th.
 

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Discussion Starter #14
Did you ever get your MPGuino running?
Not yet. I ran out of weather :/

The unit is mounted and ready to be wired up.

Good luck in the Green Grand Prix though. One thing I can tell you that I've learned from the Ultragauge in my car is that gently coming up to speed kills gas mileage. Contrary to everything I've ever believed. It's far better to accelerate briskly (50%-80% throttle) to get up to speed than go into 'cruise'. This would apply to P&G as well. Remember, half the equation is distance. If you holding the throttle open at slightly above cruising throttle to get back up to speed. Your getting 1/3 the mileage for a far greater distance.

My CBR responds the same way. I found I got the best mileage by riding briskly as opposed to careful.

Regardless, the project is still on track. I just need the weather to co-operate!
 

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Discussion Starter #16
Yep. Some great discussion at EcoModders. Peak Internal Combustion Engine efficiency is 80% throttle at an rpm just below the first torque peak. The problem with motorcycles is the extreme power to weight ratio (even a 250) means you can't use that condition very often.
I'm not so sure that that recommendation is entirely accurate in the case of motorcycle engines that are in a much higher state of tune than a typical low revving car engine. At least to the same extent. That is one of those thing I was hoping the MPGuino would answer.

But the fact remains, in a car, if your covering 500ft to recover lost speed in a P&G at 10mpg, vs 100 ft at 8mpg. You just easily negated any value of the P&G.

Additionally, I don't believe P&G on a bike is as beneficial as it is with a car. The very thing that makes small bikes so fuel efficient is what does them in. Weight. I can put my car in neutral at the top of the hill coming home from work and coast, even accelerate coming down all the way to the 2nd set of lights. A distance of over a kilometer. The bike I'm back on the gas before the first set of lights. It's that inertia thing (and aerodynamic thing).

My FJR, which is about 200lbs heavier than the CBR can coast significantly farther before I have to get back on the gas.

But it is great fun to look down at my Ultraguage and see that I'm getting 150+mpg while coasting in neutral and watch my avg mpg click up a couple of tenths before I have to slip it back into gear.

Now if only I didn't have to drive through town on a minus 30C mornings over snow covered roads...
 

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Not sure about the CBR but my 02 Honda Insight used .11 GPH at idle. Coasting in neutral with the engine running it got 150+ Mpg down to 16 MPH. Averaged 67 MPG for 30k miles. At 48 MPH coasting (engine on) it was getting 450 MPG.

regards
Badger
 

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I'm not so sure that that recommendation is entirely accurate in the case of motorcycle engines that are in a much higher state of tune than a typical low revving car engine.
BSFC pretty closely matches the inverted torque curve after choosing a certain percentage lower of rpm for friction and heat losses. I'm debating whether to add some ballast to improve pulse and glide effectiveness for the competition at Watkins Glenn. The only way to know if it is better will be to test. Probably just skip it. Show up and ride. I will break 100mpg anyway without doing anything advanced beyond some simple pulse and glide.
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Pulse and Glide for competition. Added mass? - Fuel Economy, Hypermiling, EcoModding News and Forum - EcoModder.com
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Green Grand Prix, Watkins Glenn, NY USA in April - Fuel Economy, Hypermiling, EcoModding News and Forum - EcoModder.com
 

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Discussion Starter #19
Not sure about the CBR but my 02 Honda Insight used .11 GPH at idle. Coasting in neutral with the engine running it got 150+ Mpg down to 16 MPH. Averaged 67 MPG for 30k miles. At 48 MPH coasting (engine on) it was getting 450 MPG.
Wow. That GPH is impressive. I've got a V6 Mazda GT, fully warmed up its GPH .39 in gear. In Neutral or Park, it gets about .49. I think the highest I've ever seen mine was at hwy speeds when it broke a little over 200mpg.

The Scan/Ultra gauges are worth the money and really entertaining/infuriating LOL!

I'm really interested to see if the MPGuino works with the CBR, and if it does, how the bike engine differs from the car engine.
 

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Discussion Starter #20
The only way to know if it is better will be to test. Probably just skip it. Show up and ride. I will break 100mpg anyway without doing anything advanced beyond some simple pulse and glide.
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Pulse and Glide for competition. Added mass? - Fuel Economy, Hypermiling, EcoModding News and Forum - EcoModder.com
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Green Grand Prix, Watkins Glenn, NY USA in April - Fuel Economy, Hypermiling, EcoModding News and Forum - EcoModder.com
I got a chuckle at Old Mechanics recommendation of mocking up some sort of streamlining behind you. Sounds familiar :D I like your idea of a cloth vest which would no doubt help a lot. The reason I suggested foam was to eliminate turbulence from flapping. If you go the cloth route, make *SURE* what ever you use to attach it at the back of the bike is both secure, AND will disengage in the event of a spill.

Your absolutely correct though, the only way to know is to test with some accurate measurements. Now I wish I was more diligent in getting my MPGuino hooked up to give you some solid data to work with. At the end of the day though, regular automotive hyper-miling techniques do work for bikes. I just have a sneaking suspicion they need to be modified for the unique factors a motorcycle introduces.

I'll be following the Green Grand Prix closely now :D
 
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