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Why to run a heavy duty tube at all times

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I often have guys at the track ask me why I run the Bridgestone Ultra Heavy Duty tubes at all times on my SXF. Yes, they do really increase the weight of the tire/wheel combo. But I am not a factory rider and figure that the slight loss in acceleration won't really hurt me in my quest to finish top ten in my local Vet pro class. I figure that no factory scouts are out looking for me and if I really cared I'd quit drinking so much beer and actually train.:lol:

Well I was able to provide proof as to why I run the heavy tubes last weekend. I have no idea what I hit. I do know that the bike ran this way for at least the last two hours of the day when four other guys were test riding it between my own practice motos. The tire did not go flat and still had 13psi of air in it when I pulled it all down to fix the wheel.:worthy:

Reartaco1.jpg

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I think that happened when you got some traction off a susuki that went down in the whoops in front of you. I run them too but mostly because I ride everywhere, I am too lazy to change it, and other than the time I parked my bike under the factory ktm tent for fun no pro scouts have ever wanted to know who I was.

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PS, take your brake rotor off before you let your buddies swing away at the rim with a hammer.

We're gonna use a little heat (well maybe a lot) and a BIG press. We tried a 10lb sledge at the track and it didn't even move.:lol:

You never realize how tough those Excel rims actually are until you try to bend one back. I can usually straighten a stock Honda rim with a claw hammer and a block of wood.

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if you heat it it will lose the temper, of you dont it may crack, tuff call.

Very true. Always a tough call. I figure that if I get really worried after words I'll throw the rim in my oven at home and re-solutionize the aluminum. I just would "borrow" one of my high temp thermocouples from work and not rely on the dial on my stove for the temp setting. The things you can do when you are single! If I was really feeling like going all out I could re-heat treat it as well, but I have had pretty good luck with Excels not failing after rebending.

What we ended up doing is putting pressure on the rim with the press to start with. Then slow heated the rim in the very local area with a hand held propane torch just until movement started. Took us about a half hour and lots of repositioning, but at least now the bead is sealed back up. It is not perfectly round, but it will work. I've got two more 19" rear tires to burn off and then I will relace the wheel with a new 18" rim and spokes. Or just buy a complete 18" wheel and keep this one as the "emergency" spare.

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Use a sooty flame to blacken the area that is to be heated, adjust torch to stoich.

heat area until the soot burns off the quench with water and a rag.

It will be annealed (soft) easy to reshape. Aluminum work hardens and age hardens.

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Use a sooty flame to blacken the area that is to be heated, adjust torch to stoich.

heat area until the soot burns off the quench with water and a rag.

It will be annealed (soft) easy to reshape. Aluminum work hardens and age hardens.

Yes it does. My Metallurgical Engineering degree has come in handy a time or two!:)

For those unaware, the purpose of the heating is to allow the metal grains to regrow to a larger size. This increases the malleablity of the material. When you work the metal, the grain structure is distorted and broken up. This introduces inclusions in the structure which although they do increase the strength, it also makes the material more brittle.

When many parts are manufactured, they are reintroduced to an elevated temperature oven. This process (annealing) realigns and enlargens the grains so that the material can rid itself of inclusions from the bending/forming process that made it (think of a set of handlebars). Following the anneal process, the material is aged to regain strength (just like a fine wine). Again, looking at a set of handlebars that are made of 7075-T6, the 7075 tells you that the aluminum is alloyed with 5.6 wt% (percent by weight) Zn, 2.5 wt% Mg, 1.6 wt% Cu and 0.23% Cr. The T6 at the end tells you that the alloy was solution heat treated (annealed) and then artificially aged. The artificial aging process usually involves maintaining the material at an elevated temp for a certain time period (this temp is lower than the annealling temperature from the prior process step).

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Thanks for the information. I’ve noticed a lot of people confusing

annealing and heat treating ferrous and nonferrous metals

annealing steel = cool slowly

annealing aluminum = cool quickly

Also I’ve been trying to turn lead in to gold, do you have any suggestions?

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Thanks for the information. I’ve noticed a lot of people confusing

annealing and heat treating ferrous and nonferrous metals

annealing steel = cool slowly

annealing aluminum = cool quickly

Also I’ve been trying to turn lead in to gold, do you have any suggestions?

I could suggest taking a gun full of lead bullets into jewllery store...

VOILA!....lead turns into gold into 30 seconds or less:lol:

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I could suggest taking a gun full of lead bullets into jewllery store...

VOILA!....lead turns into gold into 30 seconds or less:lol:

And it can also result in some diamonds too!

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