What is the deal with Mastiff gas tanks?

Raywood

Raywood

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stlmikie said:
On the Mastiff, we aren't suposed to be able to take the left cap off are we?
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What do you mean? On my 03 Mastiff I took the cap off all the time to gas it up. I filled the left side first to the top then put the cap on and then filled the right side to take advantage of all that 5 gl that I don't have now! :angry:

If you are having problems removing the cap then try turning it the other way!!!
 
npb4me

npb4me

Member
I was able to get the left side cap off. I had to turn it clockwise and grip it with two hands. Man that sucker was tight.
 
Fibersnake

Fibersnake

Banjo Playing PsychoBilly
Both caps on the 05 Mastiff come off and should be filled up. Also the left cap is lefty tighty, right loosy, Opposite of the right cap. While you have the cap off, it is good to occasionally put a small amount of grease or vasoline on the threads to make it easier to get off for they can swell and become a bitch.

Just tighten it down snug, no need to torque it very hard, same for right side.

Myabe the problem with the low mileage.

Do not trust the .5 for reserve. Good idea to make it a habbit to it the fuel stop at 100 range. If you hit the reserve, you can find yourself totally out within a few miles. Reserve very too much from my experience to put any faith in how far it will take you.

Good luck
 
G

Gas Man

Cool isn't cheap
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t-mack... your 2006 is a single tank not split tanks like what they are talking about.
 
Fibersnake

Fibersnake

Banjo Playing PsychoBilly
The 05 Chopper has 3.8 fuel and the way the tank is position, may allow it to use more of the fuel.

Other factors may be the jetting and any other mods on the Chopper compared to the Mastiff. It is hard to do and apple to apple comparison on different bikes, even from the same year and make, however I would think you should get in the 42-44 MPG range with normal highway riding and should be safely be able to get 100 mile runs without having to sweat running out.

Myself and many other always go for the 100 mile fill up regardless of how much we may be able to push it for there is too many variables that effect the range, from headwinds, elevations, mods, etc and I do not want to hit reserve for that is like gambling!!!

I know that Knotso has the 06 Mastiff and if not mistaken he gets a good 100 miles before the pucker factor comes into play. Knotso how is you overall gas mileage anyway.
 
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T Mack

T Mack

SUCKER FREE
KnotSo said:
My 06 mastiff does not go as far on a tank of fuel as a black 05 chopper!
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KnotSo, the guy i bought the bike from said around 80 miles start looking for a gas station? Does this sound about right for our Mastiffs? How many gallon tank do we have? How many miles are we good for?
Thanks Richard
 
Fibersnake

Fibersnake

Banjo Playing PsychoBilly
stlmike,

On the 2005 Mastiff with the split tank. The left side cap tightens up by turning CCW and tightens CW, the right side is opposite or same as as the single cap tanks. Right side seals by going CW and loosens by turning CCW, both with the plastic threads work a little better is you give then a light coating of Vasoline on the threads.

I think most Fat Bob style split tanks with two caps are similar though I can not verify. It is best to fill each tank through the specific fill cap verse trying to fill on one side only and hope it cross flows to the opposite fast enough to allow for both to be full.

Be careful not to top all the way off for the left side will leak out a little bit on the kick stand unless you rode it a few miles after fill up.

Hope this helps for those that have the split tanks on the 2005 Mastiff or similar.
 
N

nxtlevl007

Member
Fibersnake said:
stlmike,

On the 2005 Mastiff with the split tank. The left side cap tightens up by turning CCW and tightens CW, the right side is opposite or same as as the single cap tanks. Right side seals by going CW and loosens by turning CCW, both with the plastic threads work a little better is you give then a light coating of Vasoline on the threads.

I think most Fat Bob style split tanks with two caps are similar though I can not verify. It is best to fill each tank through the specific fill cap verse trying to fill on one side only and hope it cross flows to the opposite fast enough to allow for both to be full.

Be careful not to top all the way off for the left side will leak out a little bit on the kick stand unless you rode it a few miles after fill up.

Hope this helps for those that have the split tanks on the 2005 Mastiff or similar.
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I've yet to be able to get the left side cap to come off on my 2004 Mastiff, when turning clockwise. like it's glued shut!!!
 
Raywood

Raywood

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nxtlevl007 said:
I've yet to be able to get the left side cap to come off on my 2004 Mastiff, when turning clockwise. like it's glued shut!!!
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The left side should come off when turning it CCW if I remember correctly from my Mastiff days!

:flag:
 
Raywood

Raywood

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stlmikie said:
Are you guys fucking with my head or what? I can not get that pig off.
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No.... :D But it's comes off and it should be CCW. May be stuck real good.

So you telling me you've been patiently filling the tanks from the other side?

:2thumbs:
 
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