Question on KTM's tank material

[meat popsicle]

Originally Posted by Scoot Jockey

Mr. Popsicle,

Don't quote me on this, but I remember reading on the German forum that our tanks are made of a P6 composite. I would bet that traditional auto body fillers(bondo,glazing compound) would work on it though, or you could add some material through plastic welding, and sand down the area a bit to feather it out over a slightly larger area. Personally, I think it would be interesting to try my hand at making some carbon fiber guards to cover the damaged areas.

Good Luck

Scoot Jockey

P6 composite eh? I have no idea what that is; have to search around on that. Thanks for the tip.

Yeah, creeper did a great job with some CF guards to cover his rash - that is likely the best fix, however I am entertaining myself with the process of fixing the tank with somewhat native material (did you see my thread in Equipment? linked above).

[Gary]

Meat Pop,

I realize you are talking about a permanent and more structural fix that you can perform in the comfort of your garage, but just an FYI for anyone looking to patch a hole in one on the road, I'll offer the following:

My LC4 and I took a little slide on a gravel road. Ground the corner of my 18l tank so thin there was a good 1/4" circle you could almost see through and fuel was leaking from one edge.

Laid the bike over and cut out the thin circle of remaining material, and sanded around the edges to improve adhesion. Filled the hole with "fuel tank repair putty" that you buy at just about any auto store. The package says you can even use it on a wet, leaking tank. Looks like a jelly roll about 1/2" dia. and 4" long, with the center being a different color. You cut off whatever you need and then knead it until it is uniform in color. Stuff into the hole, leaving a little extra on the outside to grip the tank. Let it sit for about 45 minutes, and voila, tank was fixed, and it appears to be a solid fix. I also put a small bead of JB Weld around the edge where the putty stopped and the tank began, but probably wasn't necessary. Couple hundred miles of rough road since and no problems.

I always include this tank repair putty, sandpaper and jb weld in my tool stash.

On a side not, I also broke my shifter, but was able to fix it by attaching a 5mm allen wrench with a couple of fuel line clamps and a bead of JB Weld, also worked fine for the next couple hundred miles. The replacement shifter cost me $46, so I'm keeping the repaired one as a spare!

Gary

[meat popsicle]

Originally Posted by Happe

Hi Meat,

the Adventure Tank is from PA.

The Rally tank and also the rear tanks are made from PE.

Epoxi based fillers schould work for a little while on the Adventure tanks, if you really have to remove the marks of honour

cheers

Stefan

Thank you Stefan! I don't want to use epoxy stuff; I am looking for layperson repairs that are as close to PA as possible. Did you see my Equipment thread linked above? There is discussion of plastic welding and ski/snowboard (P-Tex) based repairs at the moment. Thanks for a piece of the puzzle!

So polyamide (PA) is the paintable stuff and polyethelene (PE) is not? I think that is it; found some evidence for this:

Originally Posted by http://www.tis-gdv.de/tis_e/verpack/kunststo/speziell/speziell.htm

Polyamide (PA)

PA is a synthetic polymer obtained by polycondensation. Depending upon the number of carbon atoms present, this thermoplastic is divided into various grades, most of which share the same properties.

PA is used in packaging applications for producing films. Due to its resistance to very low temperatures (down to -40°C), PA is used for packaging frozen goods. The oxygen and aroma barrier properties of PA film also make it suitable for vacuum packaging. Amorphous polyamides yield crystal clear films, while partially crystalline polyamides exhibit a milky haze when uncolored.

Plasticizers are added to PA films made from certain grades of PA, so excluding them from use in foodstuffs packaging. The absorption and release of water may also have negative effects.

Polyethylene (PE)

PE is a member of the polyolefin family, which are partially crystalline thermoplastics. PE is classed by density as PE-LD, low density polyethylene, density approx. 0.92 - 0.94 g/ cm3, produced by the high pressure process, and PE-HD, high density polyethylene, density approx. 0.94 - 0.96 g/cm3, produced by the low pressure process.

Both PE-LD and PE-HD exhibit a milky haze when uncolored (nearly crystal clear only when converted into thin films) and are insensitive to water. The temperature range over which PE may be used is approx. -50 - +60°C for PE-LD, while the upper limit for PE-HD is approx. 90°C, thanks to its higher density.

PE films are in particular characterized by good water vapor barrier properties. Their permeability to gases and aroma substances is, however, disadvantageous. Thanks to its higher density, PE-HD has better barrier properties towards oxygen, carbon dioxide, water vapor and aroma substances than does PE-LD.

PE is not only converted into films (PE films, composite films, shrink films), but is also used to produce bottles, bottle crates, drums, jerricans, boxes, bowls etc..

[meat popsicle]

Originally Posted by Gary

Meat Pop,

I realize you are talking about a permanent and more structural fix that you can perform in the comfort of your garage, but just an FYI for anyone looking to patch a hole in one on the road, I'll offer the following:

My LC4 and I took a little slide on a gravel road. Ground the corner of my 18l tank so thin there was a good 1/4" circle you could almost see through and fuel was leaking from one edge.

Laid the bike over and cut out the thin circle of remaining material, and sanded around the edges to improve adhesion. Filled the hole with "fuel tank repair putty" that you buy at just about any auto store. The package says you can even use it on a wet, leaking tank. Looks like a jelly roll about 1/2" dia. and 4" long, with the center being a different color. You cut off whatever you need and then knead it until it is uniform in color. Stuff into the hole, leaving a little extra on the outside to grip the tank. Let it sit for about 45 minutes, and voila, tank was fixed, and it appears to be a solid fix. I also put a small bead of JB Weld around the edge where the putty stopped and the tank began, but probably wasn't necessary. Couple hundred miles of rough road since and no problems.

I always include this tank repair putty, sandpaper and jb weld in my tool stash.

On a side not, I also broke my shifter, but was able to fix it by attaching a 5mm allen wrench with a couple of fuel line clamps and a bead of JB Weld, also worked fine for the next couple hundred miles. The replacement shifter cost me $46, so I'm keeping the repaired one as a spare!

Gary

Excellent advice Gary! have you tried to remove it for a more permanent or asthetic fix? May I translocate this to the equipment thread where I am discussing some techniques to fix plastic tanks?

[Gary]

MP,

I havn't tried to remove it, but I was going to consider that before spring arrives. I thought I would let it ride just to see how "permanent" it really is.

I was at least going to file/sand it a little to remove the gloppy look, but it's not too bad as it is. Hard to notice until you look close.

You can move this to anywhere you think it would be more useful to others.

Gary

[Happe]

Originally Posted by meat popsicle

Thank you Stefan! There is discussion of plastic welding and ski/snowboard (P-Tex) based repairs at the moment. Thanks for a piece of the puzzle!

So polyamide (PA) is the paintable stuff and polyethelene (PE) is not?

hi Meat,

You're welcome,
Had my rear tank welded a couple of month ago. Brought it to a local company that normally builds waste water systems. They weld PE & PA every day.
It is a bit of an Art to find the right temperature and pressure to have it really tight. There were two holes in my rear tank and it had cost me a pint

cheers

Stefan

[meat popsicle]

Originally Posted by Happe

hi Meat,

You're welcome,
Had my rear tank welded a couple of month ago. Brought it to a local company that normally builds waste water systems. They weld PE & PA every day.
It is a bit of an Art to find the right temperature and pressure to have it really tight. There were two holes in my rear tank and it had cost me a pint

cheers

Stefan

My other thread has some info on plastic welding (that will be improved upon) for the layperson, without easily bought local experts (). Linked above.