ADVrider

Go Back   ADVrider > Bikes > GSpot > Parallel Universe
User Name
Password
Register Inmates Photos Site Rules Search Today's Posts Mark Forums Read

Reply
 
Thread Tools Search this Thread Display Modes
Old 11-13-2010, 09:26 AM   #121
motojc
Adventurer
 
Joined: Feb 2010
Oddometer: 32
Quote:
Originally Posted by itsatdm
Surprised no one asked about my Accelerator resister, as its purpose is to trick the ECU to richen the mixture under certain conditions to hopefully get more power.
so itsatdm, tell us about your Accelerator resister I did see that, but I already have too much on my mind:) got a link? So it allow you to compensate the torque loss down low and not affect your fuel savings up high when changed to 17t? What's the catch?

flashback, what's a overdrive? had that word for my Xmoto, never understood.

And thanks guys, I'll try a 17t!
motojc is offline   Reply With Quote
Old 11-13-2010, 09:38 AM   #122
Flashback
Mommys Lil Monster
 
Flashback's Avatar
 
Joined: Jul 2007
Location: Mariana Islands via Raleigh, NC
Oddometer: 3,079
Quote:
Originally Posted by motojc
flashback, what's a overdrive? had that word for my Xmoto, never understood.
See this link -> http://en.wikipedia.org/wiki/Overdrive_%28mechanics%29

It's for automobile transmissions but you can get the idea of what I'm referring to.
__________________

Flashback is offline   Reply With Quote
Old 11-13-2010, 11:33 AM   #123
itsatdm
Beastly Adventurer
 
itsatdm's Avatar
 
Joined: Jun 2004
Location: Nor Ca.
Oddometer: 4,736
Quote:
Originally Posted by motojc
so itsatdm, tell us about your Accelerator resister I did see that, but I already have too much on my mind:) got a link? So it allow you to compensate the torque loss down low and not affect your fuel savings up high when changed to 17t? What's the catch?

flashback, what's a overdrive? had that word for my Xmoto, never understood.

And thanks guys, I'll try a 17t!
All I know is here: http://sol2.be/Accelerator/English/index.html#, in the interest of fairness its competitor is called Booster Plug. Kind of a poor mans partial ECU remap. All I can tell you is it seems to work. I can pull a gear at lower rpm than I could before and I haven't seen a appreciable drop in mileage. I did see a gain in mileage going to the larger sprocket, but the main reason was to diminish some of the vibes, as I am sensitive to them.
Did that too. The only possible downside I have personally felt has to do with cold weather. Even in California on a frosty morning, I have noticed longer to get out of that warmup mode the bike goes through. Maybe a mile instead of the previous 1/2 mile of riding.
itsatdm is offline   Reply With Quote
Old 11-13-2010, 12:44 PM   #124
Flashback
Mommys Lil Monster
 
Flashback's Avatar
 
Joined: Jul 2007
Location: Mariana Islands via Raleigh, NC
Oddometer: 3,079
Interesting mod itsatdm. I may look into that myself.

I threw my 17T on today with a new set of K60s. Done about 4 miles (to the gas station and back) about half a mile on dirt. Initial impression is that 1'st is more versatile. I could ride comfortably at higher speeds in the dirt in first where I would have had to shift up to 2'nd on the 16 T. I did try a wheelie on the street and noticed that it didn't react with quite as much gusto as it had to the throttle input on the 16 T but that is to be expected.

Update: Did 70 miles on the 17T which included about 5 miles offroad, 10 miles @ 85 on the highway, a little bit of downtown stop and go, some hard starts, wheelies, and a couple full throttle runs through the gears from stop to speed limit. The rest of those miles were back roads with speeds from about 35 to 55. I averaged 59mpg over the course of the ride where before I would have gotten 52/53 mpg on the same route.

What I noticed was that 6'th gear feels like a real gear on the 17T and that low end acceleration was not what I was used to. But I was pleasantly surprised by the 17T off road -> The gearing felt right for 35 - 55 mph gravel and dirt. Didn't do any sand or mud so I can't speak to the very low end requirements.

My impression of the 17 T is that it works well for basic commuting with a some off road fun thrown in. But I think that if I were planning a trip where I knew the bike needed to perform in really well off slab in various conditions and for long distances (like an enduro ride) I'd switch back to 16 T or even maybe drop to 15 T.

Update 2:
So I threw the bags on and have been commuting with the bike fully outfitted and have found that my gas mileage on the highway (@ 70+) with all the goodies is the same or just a little less than what I got on the 16 T.

It seems that drag is a real drag at higher speeds.

Gonna give it another tank o'gas but I usually ride fully loaded and if it turns out that I'm getting the same mpg on both sprockets when packed I'll be switching back to the 16 T.

Update 3: Second tank averaged exactly the same as the first (53 mpg) fully loaded with bags. This is exactly the same gas mileage or within 1 or 2 mpg that I'd get fully loaded with bags on the 16 T.

Summation: Gonna be switching back to the smaller sprocket as my gas mileage with bags at highway speeds decreased slightly while the gas mileage at city speeds increased resulting in a no net gain or loss of mpg situation. The 17 T just doesn't seem to fit my needs or riding style and I can actually average higher gas mileage on the 16 T on distance trips.

I think the 17 T works great when you don't have the extra drag of large bags to contend with. Without bags it did bring my MPGs up to the 60s. With bags it didn't seem make any appreciable difference overall on gas mileage over the course of two tanks.
__________________


Flashback screwed with this post 11-16-2010 at 04:17 AM
Flashback is offline   Reply With Quote
Old 11-16-2010, 10:31 PM   #125
motojc
Adventurer
 
Joined: Feb 2010
Oddometer: 32
Quote:
Originally Posted by Flashback
Summation: Gonna be switching back to the smaller sprocket as my gas mileage with bags at highway speeds decreased slightly while the gas mileage at city speeds increased resulting in a no net gain or loss of mpg situation. The 17 T just doesn't seem to fit my needs or riding style and I can actually average higher gas mileage on the 16 T on distance trips.

I think the 17 T works great when you don't have the extra drag of large bags to contend with. Without bags it did bring my MPGs up to the 60s. With bags it didn't seem make any appreciable difference overall on gas mileage over the course of two tanks.
thanks for the report. I wish I saw this BEFORE I ordered the 17T. So why is drag bring down MPG more than it's on 16T? cause it need to rav higher to keep up therefore uses more gas? I have contuned to check mine, high 47, low 45, 120mile a day, of which 110 highway, 10 city. I guess I just have to see for myself. Also, judging from my Xmoto, in summer it does 60s, winter 55 to 50, so I guess that can be the other reason mine is low right now. Do they add things in the gas in winter? There seems to be a day the MGO just drops like that, and won't come back till the next season.
motojc is offline   Reply With Quote
Old 11-17-2010, 12:58 AM   #126
itsatdm
Beastly Adventurer
 
itsatdm's Avatar
 
Joined: Jun 2004
Location: Nor Ca.
Oddometer: 4,736
I would give it a little more time. I think it takes the ECU a little time to adjust the AF mixture to the new gearing. Riding solo around my rural area, I think my first tank was 59 and by the 3rd I got 64.

I haven't done any long rides with luggage at freeway speeds with the new gearing so I can't comment. Maybe with the air resistance at those speeds and poorer aerodynamics requires more throttle input.

Frankly, I added the sprocket because of the high speed vibrations I felt at freeway speeds and I wanted to moved them up the the RPM range and mileage was secondary. I did feel the effect of the taller gearing the faster I went, it does lose some of that oomph. But I felt if I needed I could always shift down.

The accelerator resister regained the lost power and then some, but that effects mileage too. Now back to the 58-60 mpg range. No idea what it might do loaded at freeway speeds. In theory nothing, but I haven't tested it.
itsatdm is offline   Reply With Quote
Old 11-17-2010, 03:41 PM   #127
Flashback
Mommys Lil Monster
 
Flashback's Avatar
 
Joined: Jul 2007
Location: Mariana Islands via Raleigh, NC
Oddometer: 3,079
Put another hundred plus miles on bringing it to about 500 miles with the average calculated matching OBC gas mileage of 53. Seriously thought about giving it more time then decided to drop the 16T back on this afternoon.

Was headed to lunch today with some friends and tried to wheelie through an intersection. Didn't quite manage to get the front off the ground as well as I wanted...at lunch my friends remarked "WTF was that, we figured you'd roll through that intersection on your rear with the front way up in the air."

Figure that if I'm getting the same gas mileage any way, I'd go back to more low end torque. As soon as I did I noticed that with bags on I'm back to getting 60+ mpg in 6'th @ around 60 mph whereas with the 17T I was looking at the 40s for mpg at the same speed in 6'th with bags on.

Overall riding in all conditions with bags I'm @ 53 mpg on both the 17T and 16T front sprockets.

I'm pretty sure this situation is all about the extra drag that hard tail and side bags produce and the engines reaction to that drag.

Maybe someone with experience in different rear sprockets can tell us what they've experienced with changing up the rear sizes???
__________________


Flashback screwed with this post 11-17-2010 at 03:47 PM
Flashback is offline   Reply With Quote
Old 11-17-2010, 03:44 PM   #128
Ducksbane
Quaaack!!!
 
Ducksbane's Avatar
 
Joined: Dec 2007
Location: Northern NSW
Oddometer: 1,156
Iit does take a while for the engine management to adjust to changes. I have a unifilter, the accelerator module and added a leo vince carbon slip on. When I tried the LV without the baffle, the first rides were incredibly economical, if a bit louder. As the computer adjusted for the change the economy went back to what I usually get (4.7 to 4.9 Litres/100Km ... which is according to Wolfram Alpha is 48 to 50 mpg US). With more noise and no real benefit I put the baffle back in.

Gary ... I would like to have higher gearing as well and with the added torque from the minor mods I was thinking of trying the 17 tooth front sprocket. How is it offroad ... you have to slip the clutch in tight bits anyway, so does it make much difference ? I guess you could have a 15 tooth for the difficult rides and just use the 17 the rest of the time. I find that once you exceed 120Km/hr ... 75 miles an hour the economy falls drastically ... I was wondering if the taller gearing improves this at all? ... Thanks.

Will
Ducksbane is offline   Reply With Quote
Old 11-17-2010, 03:57 PM   #129
Flashback
Mommys Lil Monster
 
Flashback's Avatar
 
Joined: Jul 2007
Location: Mariana Islands via Raleigh, NC
Oddometer: 3,079
Quote:
Originally Posted by motojc
I have contuned to check mine, high 47, low 45, 120mile a day, of which 110 highway, 10 city. I guess I just have to see for myself.
45 to 47 could be right depending on your situation.

- Bags and large windshields = less gas mileage.
- Headwinds = less gas mileage.
- Hills = less gas mileage.
- Sustained high speeds = less gas mileage.

When I'm in the mountains traveling at highway speeds (70'ish) with bags on I usually average 48 or 49 if I'm doing strictly highway.

Try the 17T and see what it does for you. If it increases your mpgs, great. Success.
__________________

Flashback is offline   Reply With Quote
Old 11-17-2010, 07:09 PM   #130
swimmonkey
JMS
 
Joined: Oct 2008
Location: Austin, Texas
Oddometer: 54
'09

I now have 21K miles on my 09 F8 GS and the milage keeps getting worse and worse. It all seemed to happen at around 18K miles. Not quite sure what the deal is. I service the bike as recommended, etc..., but I've dropped from 48 mpg to about 40 mpg. Talked to the dealer about it and they told me to watch my milage until the 24K service. Very helpful - not!
swimmonkey is offline   Reply With Quote
Old 11-17-2010, 11:18 PM   #131
Flashback
Mommys Lil Monster
 
Flashback's Avatar
 
Joined: Jul 2007
Location: Mariana Islands via Raleigh, NC
Oddometer: 3,079
Quote:
Originally Posted by swimmonkey
I now have 21K miles on my 09 F8 GS and the milage keeps getting worse and worse. It all seemed to happen at around 18K miles. Not quite sure what the deal is. I service the bike as recommended, etc..., but I've dropped from 48 mpg to about 40 mpg. Talked to the dealer about it and they told me to watch my milage until the 24K service. Very helpful - not!
Off the showroom floor mine was getting 39. I knew that there was something wrong but the dealer couldn't find it. I kept complaining until they agreed to do a full run up of sensor readings and send it to BMW engineers for analysis.

We didn't get to the full run up part b/c they ended up finding a crack in my airbox at the fitting for the re-circulation line during the set up for the sensor test. As it turned out this circular crack went all the way around the fitting nipple and when they pulled the tube off there was only just a weee bit o'plastic holding it on. They replaced the airbox and my gas mileage started showing normal numbers.

The assumption that can be made there is that my bike came from the factory with the crack in the airbox.

Any compromise of the air flow system will give you an extreme loss of gas mileage. That's a good place to start troubleshooting.
__________________

Flashback is offline   Reply With Quote
Old 11-18-2010, 12:31 AM   #132
itsatdm
Beastly Adventurer
 
itsatdm's Avatar
 
Joined: Jun 2004
Location: Nor Ca.
Oddometer: 4,736
Quote:
Originally Posted by Ducksbane
Iit does take a while for the engine management to adjust to changes. I have a unifilter, the accelerator module and added a leo vince carbon slip on. When I tried the LV without the baffle, the first rides were incredibly economical, if a bit louder. As the computer adjusted for the change the economy went back to what I usually get (4.7 to 4.9 Litres/100Km ... which is according to Wolfram Alpha is 48 to 50 mpg US). With more noise and no real benefit I put the baffle back in.

Gary ... I would like to have higher gearing as well and with the added torque from the minor mods I was thinking of trying the 17 tooth front sprocket. How is it offroad ... you have to slip the clutch in tight bits anyway, so does it make much difference ? I guess you could have a 15 tooth for the difficult rides and just use the 17 the rest of the time. I find that once you exceed 120Km/hr ... 75 miles an hour the economy falls drastically ... I was wondering if the taller gearing improves this at all? ... Thanks.

Will
I wish I could be more definitive but really can't. I really don't ride the bike on what can really be called hardcore stuff anymore, though I live in close proximity to a lot of it. Figured that is what the thumper is for.

I ride a lot of Sierra Nevada logging roads, some have not have been improved on in 20 years. With the 17 tooth and the Accelerator resister, none has caused any problems. Found some steep hills to see how slow I could go. 8 mph was about the limit and 10 was better. Very smooth and responsive. Probably a 20% grade, but paved. Conjecture on my part, but I think anything I could do with the 16 tooth, I can do with this set up.

The more I ride, the more impressed with what a little richening of the mixture does. Just feels like a different bike. My enthusiasm is starting to show in the mileage.

If I take it to Death Valley in January, that will be the test. First time, all stock, the bike was practically unrideable in the rocky spots.

Ditto on the high speed stuff too. Last high speed ride was again to Death Valley with camping gear. Stock set up was 48 mph, so that is the bench mark. I can't see it getting any worse than that, as it should be running on the map. 75mph, does seem to be the tipping point. I had some strong headwinds on that trip that got me down 33mph according to the OCB. I think the key to good mileage is to keep it in the closed loop mode, but I do not know how you tell.

Making this bike perform off road, really required a number of changes. The suspension sucks, the throttle is way too abrupt for slow going or rocks, The fueling at low rpm is bad and probably a few others I have not thought of and I modded them all. It finally feels right, so I am looking forward to a re bout with DV because I can still remember how it used to be.

Not to helpful, but that is all I got

Well maybe a little more. Everybody has a different view of offroad. Here are some pics, not mine, of what I consider my limits. http://www.advrider.com/forums/showthread.php?t=635453. Not done them all on the 800, but have done the back road to Darwin, Saline, Lippencott, Hunter Valley, Goler wash, Mengle Pass plus a few other they did not do. I would do them all with this gearing except Mengle uphill. Brought it up because of your gear slipping comment. Not much needed in this type of terrain.

itsatdm screwed with this post 11-18-2010 at 01:00 AM
itsatdm is offline   Reply With Quote
Old 11-18-2010, 04:13 AM   #133
capt_enduro
tool whore
 
capt_enduro's Avatar
 
Joined: Sep 2008
Location: NW Georgia
Oddometer: 191
The Variables:
Units: Miles per US gallons
Odometer: 12500 miles
Rider: 5'7" 180 lbs
Luggage: Stock Vario Side Cases + Dry Bag, Tent, Tripod etc. on back.
Windscreen: Stock
Exhaust: Stock
Tires: Metzeler Tourance
WX: 70% of the time riding in pissing rain (especially on long trips)
Riding Conditions: 30% commuting, 60% back roads, 10% fire road

Results:
Commuting and back roads, always fill up at 160 miles and end up buying 3.2 gallons of gas every time = 50 mpg. Flog it on the superslab all day at 80+mph and the mileage drops to 43 mpg.



__________________
Omnis vestri substructio es servus ad nobis

'09 BMW F800GS
'09 Kawasaki KLX250S
'05 Yamaha TTR230
capt_enduro is offline   Reply With Quote
Old 11-18-2010, 06:32 AM   #134
Ducksbane
Quaaack!!!
 
Ducksbane's Avatar
 
Joined: Dec 2007
Location: Northern NSW
Oddometer: 1,156
Quote:
Originally Posted by itsatdm
The more I ride, the more impressed with what a little richening of the mixture does. Just feels like a different bike. My enthusiasm is starting to show in the mileage.
I have noticed this effect myself!

The ride report you referenced looks interesting ... some of that stuff looks pretty hard on an 800! I don't often do anything that difficult myself ... I have most of my low speed problems on my farm ... if I rode it there and I am not doing anything too difficult I sometimes take the 800 out to look at things and to move the sheep and cattle if the terrains not too hard. It's a bit heavy, unmaneuverable, and high geared for this, but it is very comfortable and civilised!

Simon Pavey the Australian in "Race to Dakar" who teaches off roading big bikes says that you should use a higher gear and slip the clutch because it gives you more control and helps contain excessive throttle response from large bikes. Who am I to argue?

Anyway thanks Garry ... I think I will try gearing it up and see how it goes ... BMW are giving me new chain and sprockets so I am hoping they can give me a front off an F650. I hope you enjoy Death Valley and post your ride report so we can all enjoy it ... don't foget the pictures
Ducksbane is offline   Reply With Quote
Old 11-18-2010, 02:35 PM   #135
itsatdm
Beastly Adventurer
 
itsatdm's Avatar
 
Joined: Jun 2004
Location: Nor Ca.
Oddometer: 4,736
I have been comparing the claims of Booster Plug and the Accelerator module and something caused me to pause.

They both seem to work on the same principle, but the Booster plug raises the issue of how the resistance could actually give too much fuel in hot environs and of course their solution.

I don't know if the Accelerator has that feature. It is cool here, how about where you are? Any problems on hot days such as bogging, fuelling issues or major changes in mileage?
itsatdm is offline   Reply With Quote
Reply

Share

Thread Tools Search this Thread
Search this Thread:

.
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On

Forum Jump


Times are GMT -7.   It's 12:25 AM.


Powered by vBulletin® Version 3.8.5
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Copyright ADVrider 2011-2014