HD tube failure

[AZJW]

Here's another wrinkle on a tube failure. MotoZ Tractionator Heavy Duty tube suffered a catastrophic failure at about 40 mph on a dirt road. Handling wasn't particularly ugly as the stiff walled MotoZ RallZ 150/70-18 contained the rim and I didn't do any damage to the tire.  There was a small hole in the center of the tire between the knobbies where air was escaping, but once the tire was dismounted, that hole wasn't visible.  

 

The tube on the other hand was a total write off, which has me questioning whether or not HD tubes are worth the extra weight and cost. A standard 2mm Dunlop tube went back in the RallZ along with 12oz of OKO tire sealant.  We'll see how that combination plays with the sharp AZ rock gardens where this bike often goes.

Emailed MotoZ for comment/ feedback, I'll post up here their response.

 

[AZJW]

Ok, the " official" answer on this issue is that I was running too small of a tube (140/80-18.  4.00-18) in my RallZ 150/70-18 tire.  Apparently the too small of tube failed due to trying to fill the excess cavity space of the 150 tire.

 

Apparently they've been offering larger sized tubes in HD for a couple of years,  but I don't usually run their heavy tubes, so I missed that.

Word on the street is the 3mm Thickness of the 5.00-18 will be available in the states early next year.

 

Anyway, I'm wiser now and will absolutely have a larger 5.00-18 inside when I change it out.

 

MOTOZ TUBES - Motoz

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High Quality Natural Rubber Natural properties like a surgical glove (resists damage when stretched and compressed). 3 Types / Thickness Available: 1.4 mm Standard Series 3 mm Heavy Duty Racing...

 

[RioRideNM]

Glad all ended well. I have seen many a time people say “any rear tube will fit” which is just not right with bikes like this. I have never had issues with HD tubes and will still use them given my needs, but i do my best to not let them be in the bike more than about 18 months or so due to my replacing tires so often. keeps the rubber fresh 

[Hollybrook]

I know it's not really this simple, but a 150/70 cross section is only about 20% greater area than a 140/80.

 

That said, Motoz makes a big deal about their natural rubber tubes being made to a size that doesn't require stretching to fill a tire.  If it is that important for natural rubber tubes, it seems even more important for butyl ones. 

 

The stock Pirelli rear tube is specified to fit a wide variety of sizes ranging from 110/90 to 5.10.  You have to wonder...