2008 Mastiff - Gas Mileage

Energy One
Still trying to get used to my new 08 Mastiff - from the ride on that big, fat, monster 300 tire in the back :) to living without a gas gauge (bike is not EFI). I've taken it out for about 3 rides so far and I filled it up before the 2nd ride. I reset the odometer at that time and rode for about 40'ish miles.

Took it out again this past weekend and was at about 90 miles when the bike started to sputter. I clutched the bike, throttled a few times, and it sputtered a few times, and then seemed ok. Took off again and about a minute later it started to sputter then turn off.

I pulled over, switched to reserve, pumped the throttle a couple of times, started the bike, and off we went.

I pulled over at the nearest gas station (I was at about 100 miles here) and filled it up. The tank filled up with 2.5 gallons so I'm thinking I wasn't running on empty when the initial sputter occurred.

I'm thinking I had a bad batch of fuel the last time I filled - I couldn't have been out of gas, could I?

What type of mileage do these bikes get?

Thanks!

-Samson
 

narow37

Angry Southern White Man
I always fill up around 100-120 but I always seem to have about a gallon left. I have a K9 which is a 4.4 gallon tank. Yours is a 4.6 including the reserve so it should be about the same given that you ride the same but, every bike is different.
 

Dakotabos

Well-Known Member
Calendar Participant
Troop Supporter
No way were you out of gas. When you fill your bike do you fill it to the neck of the tank?
Have not checked the specs on your bike but thinking it should be 4. some gallons of gas.
Just checked and your bike fuel specs
Fuel - Total......................................................... 4.6 Gal
Fuel - Main......................................................... 3.9 Gal

One problem might be check your reserve switch. Make sure its full on and not sticking.
OR
It might be vacum lockup on you. Not sure if Big Dog has fixed the problem they had with the gas cap not venting.

My 04 Chopper needs fuel every 125 miles and usually takes 3 to 3.5 gallons
 

Chopper Dave

SIICK!!!
First of all Welcome.....:cheers: you should go in the introductions and introduce yourself...then pin the map.....and after that ....lets see some pic's of your scoot!
Congrats on your new bike....:up:
 

barhopper

Another round please
I took out my venting in my cap. Fixed that problem. I get gas from 80 to 100 miles just to be safe.
 
Thanks all for the info! I'll look more into the venting on the cap.

And I'll go through the introduction as well... :)

Lovin' the bike, btw. Last ride before this was an '06 HD Springer Softail. Man... am I glad I made the change...

-Samson
 

Raywood

The Pirate
Staff member
Calendar Participant
Troop Supporter
Welcome to the forum. a couple things for you to know as a new owner.

1. don't use the enricher if you don't have to and then only to start the bike and then turn if off and use the throttle. It will foul your plugs very quickly.
2. get a battery tender if you don't already have one. Your motor needs lots of power to the starter to start up so keep you battery in tip top shape.
3. reset your tripometer after every fill and you will get to know how many miles you can get on a tank. I get about 125-145 with a 3.4 gl tank. You will learn that some of our models don't have much reserve even though the manual says we do.

Oh, how did you hear about us?

Later,
Ray
 

BBChopper

Supports 2 Disabled Vets
Troop Supporter
Sounds like all models get about the same. I start looking between 85-90 miles depending if I know the area or not. If not I look sooner, I hate to push!!!:roll:
 

WB Cycles

Well-Known Member
I hit 100 .... I start to get nervous on the chopper. Past experience tells me I have another 10 max.
 

KnotSo

Admin
Staff member
Couple of observations:
1. The tank on the mastiff, the fill hole is in the wrong location and the petcock is in the middle of the tank. :rant:
2. I have never put in more than 3.7 gals and have hit reserve several times, running out twice coasting into the svc station.
3. normally fill up at the 100 yardstick but will go a bit further with a good amount of concern.
4. This is the best point: around 90-115 mph you get incredible mileage, seriously. :2thumbs:

See Ya!
 

Vegas

Well-Known Member
I agree with Knotso. I have been on reserve and only got 3.7 in the tank. Most of the time when I fill up I only put in 2.5-3 gallons. If you are not topping off you could very well have been on reserve. Do not top off unless you plan to ride for atleast 30 miles.
 
Welcome to the forum. a couple things for you to know as a new owner.

1. don't use the enricher if you don't have to and then only to start the bike and then turn if off and use the throttle. It will foul your plugs very quickly.
2. get a battery tender if you don't already have one. Your motor needs lots of power to the starter to start up so keep you battery in tip top shape.
3. reset your tripometer after every fill and you will get to know how many miles you can get on a tank. I get about 125-145 with a 3.4 gl tank. You will learn that some of our models don't have much reserve even though the manual says we do.

Oh, how did you hear about us?

Later,
Ray
Excellent points - will remember to do that. I know the instruction manual talks about using the enricher for every cold start - is it really necessary? :confused: My previous bike was EFI so I didn't worry about that and it's been a long time since my last carburated cycle...

I'll go get me a battery tender this weekend - gonna make a run to S.A. anyway, might as well do it while I'm there.

As for this site, I'm glad I came upon it. I googled for a Big Dog group and the first site I went to really sucked (i'll leave it off just for the sake of being nice). I couldn't even register... plus the black on blue (or was it white on blue... whatever) screen was killing me...:angry:

Again, thanks for all the pointers, guys... awesome!
 

P8RIOT

Well-Known Member
Calendar Participant
When my bike was new, I found I had to use a bit of enrichener to have it start immediately and reliably - but then I would push it off immediately. After it broke in, though, there was no need for the enrichener at all. Now all it takes is one or two full twists of the throttle so the accelerator pump shoots in some raw gas, and it fires right off every time.
 
Welcome to the forum. a couple things for you to know as a new owner.

2. get a battery tender if you don't already have one. Your motor needs lots of power to the starter to start up so keep you battery in tip top shape.

Ray
Do I need to be specific about which type/model/brand/etc of battery tender that I get? Just wondering if there's any reason I need to go with the one that the BD dealership carries or if I can run to the local motorcycle shop and get one...

-Samson
 

Raywood

The Pirate
Staff member
Calendar Participant
Troop Supporter
Do I need to be specific about which type/model/brand/etc of battery tender that I get? Just wondering if there's any reason I need to go with the one that the BD dealership carries or if I can run to the local motorcycle shop and get one...

-Samson
Your local HD dealer has a branded one that works great.
About $30

Keep you Dawg on life support!!! :cheers:
 
Cool - I found a place here in Round Rock (BatteriesPlus.com) that carries the Battery Tender Jr. for $29.00... I'll swing by after work and get me one... :)
 

Raywood

The Pirate
Staff member
Calendar Participant
Troop Supporter
Cool - I found a place here in Round Rock (BatteriesPlus.com) that carries the Battery Tender Jr. for $29.00... I'll swing by after work and get me one... :)
You can wire up the battery and run the pig tail either out the front between the battery covers and rear cylinder or out the back between the seat and fender. Where ever you like it. :D
 

P8RIOT

Well-Known Member
Calendar Participant
There are cheaper places to buy them than at the dealers - most are probably using the "Battery Tender Jr." They really don't cost much, and they do add a lot of peace of mind.
 
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