Difference between tanks?

[seichtersvtx]

It seems to me that I remember reading that all the fuel tanks besides the C and F are interchangeable. And the C and F are only interchangeable with each other. I believe that the 02 to 04 C models had an in tank fuel pump, where as the 05 and newer went to the external pump setup. So what makes the 05 C tank NOT interchangeable with the other models? My understanding is that the R, N, T, and maybe others have a larger fuel capacity which is the main reason I was maybe considering swapping it for a different model. If they are different, is it something I could change to make fit or work? What exactly are all the issues with trying this tank swap?

I have an 05 1800C spec 2.

Any insight will be appreciated!!

[Chicago-Spike]

It's the indent on the top of the tanks where the chrome dash sits. They are different shaped and the bolt spacing is different from the C/F and the RTN

[X'N]

It's the indent on the top of the tanks where the chrome dash sits. They are different shaped and the bolt spacing is different from the C/F and the RTN

A 04 or newer RSNT tank will bolt up fine but you will have to change your speedo as spike said.

[seichtersvtx]

Hmm . I don't mind the idea of having the Speedo on the tank. I personally think it gives more of a cruiser look to it. The only down side at this point is the factory paint job. I currently have the black with silver tribal flame. There are 4 stickers on the tank alone and just one of them was 80 bucks. Not sure if its still that much. Unless I go with a complete different paint job to customize it up a little. The flames carry on to the front and rear fenders, so just painting the tank black without throwing the tribal flames will be hideous to me. Ideas ideas!!! I feel a future mod coming on! One other question, does the seat still fit up to the tank the same? I think the other models have a different seat but I could be wrong.

[X'N]

The tank is shaped the same around the seat on all the 05+ tanks

[ra3boy]

if this helps: 2007, first and last year, all 1800C had F dash and fuel tank.

[seichtersvtx]

What about swapping speedometers? Since mine is on the handlebars, and all the others are on the tank, will my speedometer harness plug into the tank mounted speedo of the other models? That's about the only other issue I can think of coming across. Once I figure this out, this will probably be a project after this riding season along with a complete custom paint job. I'll probably need a new fork cover since the speedo will no longer be needed there. Maybe I can find on of those used off of a different model if it will bolt up fine.

[3Mutts]

Here are a few pictures I have of each of the tanks, I can take other views of them and measurements if wanted. I have all 4 of the 1800 tanks on hand if you need any info.

02-04 1800 R, S use same tank, same dash (also same dash as 05+)
02-04 1800 C has it's own tank & dash
05+ 1800 R, S, T, N all use the same tank & dash
05+ 1800 C, F use the same tank & dash

The 02-04 on all models have a visible tank seam along the lowest edge and have a rounded rear profile similar to the 1300 & 750 tanks. The 05+ models have no tank seam with smooth transition from top to bottom and the rear has a obtuse angular edge (mates up to the seat slightly tighter than the 02-04)

Pics:

05+ VTX1800 C/F Showing on the bike with the dash in place:



05+ VTX1800 R/S/T/N showing on the bike with the dash in place:



Comparison of the 05+ C/F (left) and 05+ R/S/T/N (right) bare tanks with dashes off.



The bottom retention bracket is the same size and same distance from the tube brackets at the front of the tank so mounting won't be the issue, just the dash replacement, gauges, wiring and gas cap will be different. The wiring harness may or may not match up, the C/F have a digital readout if I recall correctly whereas the R/S/T/N have an analog speedo.

Good luck with the project!
Chris

[X'N]

If you get a 2005 or newer dash it should be plug and play.

[seichtersvtx]

Thanks for the pics 3mutts. The top two pics are labeled backwards, but the pics side by side helps out. The C model is an analogue speedo, just that it's on the bars as opposed to being on the tank as all the other models. Now that I know that mounting wont be an issue, I just have to figure out the electrical of the speedo and the rest of the dash. If someone has a picture of the electrical plugs on the other models, that might help to at least figure out if it plugs in the same. So if someone could maybe look at theirs and shoot a pic of it, I would appreciate it. Once I figure all this out and finish the mod, I will be sure to create a post in the "how to" forum for others that may decide on the same mod. However, if I can't figure the electrical out, that will probably knock the wind out on my sails on the project. I want all my ducks in a row before I pull the trigger on buying a different tank.

[X'N]

I can say this when I switched from my 2002 1800c speedo to a 2005 1800F speedo the plugs were different but the wiring was a tad different but that was only different because the F has a factory tach lead that comes from the computer as well as some turnsignal wire differences but being your bike is newer as I said it should be plug and play. I believe all the 05+ bikes have 2 little black wire connectors for the speedo/dash connections.

[3Mutts]

Thanks for the pics 3mutts. The top two pics are labeled backwards, but the pics side by side helps out. The C model is an analogue speedo, just that it's on the bars as opposed to being on the tank as all the other models. Now that I know that mounting wont be an issue, I just have to figure out the electrical of the speedo and the rest of the dash. If someone has a picture of the electrical plugs on the other models, that might help to at least figure out if it plugs in the same. So if someone could maybe look at theirs and shoot a pic of it, I would appreciate it. Once I figure all this out and finish the mod, I will be sure to create a post in the "how to" forum for others that may decide on the same mod. However, if I can't figure the electrical out, that will probably knock the wind out on my sails on the project. I want all my ducks in a row before I pull the trigger on buying a different tank.

No problem, glad to help.
I fixed the pic placement for future referencers, was trying to get things posted on my way out the door from work to go home & brain must have frozen...lol

[seichtersvtx]

Here is the pics of what all my plugs look like. Like what X'N said, I have the two little black plugs that come from the dash bezel. Both are the same style plug, just that one is male and the other is female. the female has the green around the inside. There is also a clear plastic plug that is from the speedometer and it goes into the headlight bucket where it plugs into another harness. This one is a larger 6 pin plug which only 5 pins are used.

The two black plugs.
Black plugs 2.jpg

The Speedometer cable where it plugs in behind the headlight.
Speedometer cable.jpg

My only problem now is when I search for the model speedometer, I see ones that have completely different plugs on them. I have searched on Ebay and it seems the ones I come across, although listed as for a 05 and newer, have the older style plugs on them. The older ones had the speedometer drive cable on them. Maybe they are just using a generic photo, not of the actual part since most I find are from businesses. I just want to verify 100% that the plugs will be the same before I buy anything. Also, if it's just the two little black plugs, is the clear plug where the speedo currently plugs in just an extra speedo cable installed for use on the C model? I found a pic of an F model dash and it seemed to only have the two black plugs, which is why I wonder if the current speedo cable is just extra for plugging into the C model speedo. I don't want an F model speedo though. I want the tank mounted analogue that the other models have.

[X'N]

There are no speedo drive cables on any vtx's.

[X'N]

If you look at the wire schematics you may be sol...

You need a green with a black stripe and pink with a green stripe wire for speedo indication. It only shows it going to the connector in your headlight. Now there is a chance that Honda wired your bike with the wires in the plug already because the later year 1800C's came with F dashes and would need those 2 wires. Look at your plugs (on the bike wiring not the dash side of the connectors) and see if you have them in the small 2 black wire connectors.

But really worse case is you would have to cut the plugs off of your dash and speedo and wire them to the new gauge.

[seichtersvtx]

If you look at the wire schematics you may be sol...

You need a green with a black stripe and pink with a green stripe wire for speedo indication. It only shows it going to the connector in your headlight. Now there is a chance that Honda wired your bike with the wires in the plug already because the later year 1800C's came with F dashes and would need those 2 wires. Look at your plugs (on the bike wiring not the dash side of the connectors) and see if you have them in the small 2 black wire connectors.

But really worse case is you would have to cut the plugs off of your dash and speedo and wire them to the new gauge.

I only see those wires going to the plug behind the headlight. I don't have the wiring schematic for my year and the only ones I find are for earlier years. If if have to rewire it, I'd like to find a schematic so I can see what all I need to do to swap it over.

[seichtersvtx]

Well so far by comparing the wiring schematic of my C model to that of an 06 R model, those little black plugs are wired differently. So definitely not a plug and play setup. Those plugs are a part of the main engine overlay harness which I have to say is a stupid design. I can't believe it was cost effective to have a different engine overlay harness for each model. They should have made one main harness, then model specific harnesses to split off of that if need be. I can't believe how differently they are wired. All the wires are colored differently, and I still have to trace back on the schematics to see what all is actually different. For sure the turn signal circuit is different since the other models use two signal wires for the left and right turn signal indicators. To me, I would think it would have been easier to design one harness, and just wire it differently where they plug in. I guess that would have made to much sense.

[X'N]

Honda has kept the same color codes for most all the functions for years. The only real difference is the turnsignal between the rsnt's and the 05+ C model is the turnsignal relay for the C's use a black/red stripe wire that goes to the dash to signal the indicator light. The RSNT's have 2 dash indicator lights. If you tap into the orange and light blue turnsignal wires running to the rear signals and run them to your dash you'll be fine. Oh yea and you won't need the yellow wire going from your dash to your speedo, its a reset button for your trip meter.

This is a list I made when I was wiring my F dash to my C... Hope it helps.

Right turn signal	Light blue / white
Left turn signal	Orange / Black
Neutral indicator	Light green / Red
High beam indicator	Blue
Temp indicator	Green / Blue
Fuel reserve indicator	Brown / Black
PGM-FI	White / Blue
Oil pressure indicator	Blue / Red
Ground -	Green
IGN +	Black / Brown
TA sig (tachometer)	Yellow / Green
Sensor GND	Green / Black
Speed sensor signal	Pink / Green
Back up	Red / Green

[Jon's1800VTXC]

If interested, I have a late model (seamless tank) from an R/N that has a pop up cap. It needs the inside cleaned out, resealed and the body work/paint redone. We had paint bubbling issues and I got tired of being down so I bought another tank. pm me if you're interested. You can keep the bar mounted speedo that way if you want. I had it on my 03C with an aftermarket fuel pump.

If you want to fix up a damaged tank I also have a complete tank with gauges/speedo from a wrecked 05N

[Tejas_Ranger]

Here are a few pictures I have of each of the tanks, I can take other views of them and measurements if wanted. I have all 4 of the 1800 tanks on hand if you need any info.

02-04 1800 R, S use same tank, same dash (also same dash as 05+)
02-04 1800 C has it's own tank & dash
05+ 1800 R, S, T, N all use the same tank & dash
05+ 1800 C, F use the same tank & dash

The 02-04 on all models have a visible tank seam along the lowest edge and have a rounded rear profile similar to the 1300 & 750 tanks. The 05+ models have no tank seam with smooth transition from top to bottom and the rear has a obtuse angular edge (mates up to the seat slightly tighter than the 02-04)

Pics:

05+ VTX1800 C/F Showing on the bike with the dash in place:



05+ VTX1800 R/S/T/N showing on the bike with the dash in place:



Comparison of the 05+ C/F (left) and 05+ R/S/T/N (right) bare tanks with dashes off.



The bottom retention bracket is the same size and same distance from the tube brackets at the front of the tank so mounting won't be the issue, just the dash replacement, gauges, wiring and gas cap will be different. The wiring harness may or may not match up, the C/F have a digital readout if I recall correctly whereas the R/S/T/N have an analog speedo.

Good luck with the project!
Chris

Not quite correct on 1800 '04 R/S/N. That was the year Honda went with the seamless tank on those models. Before that it was the seamed tank. difference in two tanks, seamless has fuel pump outside the tank, seamed tank fuel pump is inside the tank.


Tejas

[3Mutts]

Not quite correct on 1800 '04 R/S/N. That was the year Honda went with the seamless tank on those models. Before that it was the seamed tank. difference in two tanks, seamless has fuel pump outside the tank, seamed tank fuel pump is inside the tank.


Tejas

Some of my clients with '04s have had seams and some with seamless.
Not sure when exactly in the model year the changeover happened but it's caused confusion more than once when talking bib fitment so I now ask every 04 R/S owner which tank they have to be sure.
Might simply be that some 03's didn't complete in the production year and simply rolled over...not common in a model redesign year but not unheard of either.

You're absolutely correct about the N and the part about the fuel pump/tank combos.

[Tejas_Ranger]

Some of my clients with '04s have had seams and some with seamless.
Not sure when exactly in the model year the changeover happened but it's caused confusion more than once when talking bib fitment so I now ask every 04 R/S owner which tank they have to be sure.
Might simply be that some 03's didn't complete in the production year and simply rolled over...not common in a model redesign year but not unheard of either.

You're absolutely correct about the N and the part about the fuel pump/tank combos.

Not a problem. I only know what I do because my '04 R is a seamless tank model. Another difference is the radiator size on some of those models. I also found that out the hard way ordering a new nicer grill insert. Some rad's are shorter and fatter where others are taller and narrower.


Tejas

[seichtersvtx]

If interested, I have a late model (seamless tank) from an R/N that has a pop up cap. It needs the inside cleaned out, resealed and the body work/paint redone. We had paint bubbling issues and I got tired of being down so I bought another tank. pm me if you're interested. You can keep the bar mounted speedo that way if you want. I had it on my 03C with an aftermarket fuel pump.

If you want to fix up a damaged tank I also have a complete tank with gauges/speedo from a wrecked 05N

Do you have pics of the tanks? How much are you looking to get for them? The one with the paint bubble, is that just a paint defect or what? Also, how many miles are on the speedometer on the damaged tank?

[3Mutts]

Not a problem. I only know what I do because my '04 R is a seamless tank model. Another difference is the radiator size on some of those models. I also found that out the hard way ordering a new nicer grill insert. Some rad's are shorter and fatter where others are taller and narrower.


Tejas

Gotta love it when they do that. As I add Harley's to my leather line-up I'm finding they were even worse than Honda and such. One main model can have 3-5 offshoots/styles and each of those will have minor changes like the distance between the rear seat fender bolts of 5/8" from one to the next. How's that for messing with the aftermarket makers?!

[Mick-S]

If interested, I have a late model (seamless tank) from an R/N that has a pop up cap. It needs the inside cleaned out, resealed and the body work/paint redone. We had paint bubbling issues and I got tired of being down so I bought another tank. pm me if you're interested. You can keep the bar mounted speedo that way if you want. I had it on my 03C with an aftermarket fuel pump.

If you want to fix up a damaged tank I also have a complete tank with gauges/speedo from a wrecked 05N

Sent you a PM about the tank with the pop up cap.

[daryls]

If interested, I have a late model (seamless tank) from an R/N that has a pop up cap. It needs the inside cleaned out, resealed and the body work/paint redone. We had paint bubbling issues and I got tired of being down so I bought another tank. pm me if you're interested. You can keep the bar mounted speedo that way if you want. I had it on my 03C with an aftermarket fuel pump.

If you want to fix up a damaged tank I also have a complete tank with gauges/speedo from a wrecked 05N

I have 2003 1800C as well. I have a dumb question just how big, in gallons, is the tanks you are selling verses my original tank?