fuel indicator

[g2501]

I've read a lot about the issues related to the installation of a fuel level indicator on the gen.1 vmax, and some days ago I've found this on the bay :

their website seems to be in maintenance mode , but it's working and seems that they are selling a lot of this product.

I know that this is the solution to a problem that is not existent, since if you take care to zero the miles on every fueling and pay a lot of attention of it you should be safe, but since I'm a pretty lazy guy I would love to find a solution

What do you think about it guys?
Also , some of you tried the ultrasonic probe method?

 

[Fire-medic]

The fuel gauge does not work when it is connected to a pipe, into which the fuel is delivered by a fuel pump. (It can be used if the motorbikes is equipped with some types of external fuel pump
-from their web site

Looks interesting. But without further info, this is possibly not going to work. Their link about an external fuel pump explanation is not currently working. I suggest contacting them if you wish.

Possibly connecting their T-pipe before the fuel pump may work.

 

[Buster Hymen]

Looks interesting but by the explanation it seems that it would only work with a gravity fed fuel system. Could be wrong though.

 

[one2dmax]

We've done it a few times and not all that difficult. Just need the gauge requirements so we can get the correct sending unit.

 

[gentsvmax]

There are more drop-in sending units now than going the route I did in making one. Like Sean said, matching a gauge to the sending units ohm range is about the only challenge now. Building in the gauge is mod monkey catnip.

 

[Fire-medic]

The new gauge array looks good, did you cut-in a new hole to mount the gas sending unit? Did you weld-in nuts inside the gas tank to accept the new bolt pattern?

 

[gentsvmax]

Yes and no, (practiced with a donor tank) I used a hole saw just big enough to get the arm in and tap size mounting bolt holes.
I was able to thread in the mounting bolts up through the sending unit arm hole.
Carefully put the gasket on and guide the sending unit arm down into the tank and REALLY carefully set the plate on the bolts with lock washers and the nuts. The whole
project reminded me of those ship in a bottle displays that I had allways wondered how they did that.

 

[Fire-medic]

Looks like it came-out pretty-good. Did you have to bend the float level rod or leave it stock shape?

What was the resistance value of the sending unit you chose, and what is the application in the auto it fits, thanks.

I've often thought of putting a pipe extension onto the gas tank drain plug, and routing it over to the side of the bike, where you would have easier access to it if you needed to drain the tank. You would either use a valve at the side of the bike, or have it terminate at a female fitting, and just remove a plug to allow it to drain.

 

[gentsvmax]

Yes,I had to cut the float rod and make the two sleeves shown in order to play with different angles until it would swing a complete full to empty arc, allow for the fuel reserve indicator as well as accommodate the cutout in the tank for the wide wheel transfer case, similar to a chain drive cutout. That block of wood in the donor tank is my cutout simulator. I then measured resistance from full to empty on the gauge, I think about 480 empty to 150 ohms full. The gauges were easily available at Auto zone, O Reillys and Advanced auto parts. According to the gauge instructions its a common range for GM sending unit applications. That sending unit is from a ZX1300 Kawi. according to its marking from Steels salvage here.

 

[g2501]

I’ve sent an email to those guys and they replied me back with some more insights.
This is what they told me :

This system should be usable. But the gauge sensor must be placed under the tank and the hose must be connected between the tank and the fuel pump. Please, check the air ventilation of the tank. Any ventils can cause problems – there must be atmospheric pressure in the tank.

So, for what I understand Basically the only 2 requirements for this system to work are:
1- the tank must be in atmospheric pressure (no vacuum inside or something similar)
2- the unit must be below the tank.
This is needed because the system work using the pressure of the fuel in the stank as an indication of how much is full.
I think that the Vmax tank works on athmosferic pressure , and regarding the CPU unit that needs to be below the tank maybe it is bossible to use the hole that is already in place for the original sensor .
I would like to make this mod without dismounting the tank , and most important without making any hole.
Of course I have to sacrifice the original fuel warning light, but I can have a more precise indication of how much fuel I have in the tank, and most important I can program it with the exact amount of fuel I want.
My Idea is :
Install the new system on the bike, put 1 or 2 liters of fuel and set for the first light to turn on , put another 2 lt and go on like this until the tank is full.

Can you guys make me a favor?
Since right now I do not have access to my bike and I don’t remember how it is made on the bottom side , can you tell me if there is some sort of protection between the tank and the exhaust? It can be possible to install this unit between the tank and the exhaust? Or are they too close to let this configuration works correctly?

 

[gentsvmax]

I say go for it and make it work for you, something for the mod monkey to gnaw on anyway.
I only have experience with my bike as I got it VERY used(many parts missing) not stock exhaust but with a dented, bent and bruised kerker 4 into 1 header, about the same amount of room between the bottom of the tank and the pipe I imagine. I am almost 100% sure I had to remove the low fuel sensor at one point and had plenty on room to take it out (remove two 10mm-head bolts) with tank in the bike. There was no type of heat shield nor provision for any type unless it was a dynamat type of glue on protection that had since fallen off. I can see an aluminum piece made to fit that spot, drilled and pipe tapped for a 90 degree fitting for your bottom fuel line to that processor for your gauge. I only have pics of the bottom of the tank from the inside if that will help.