I want to extend the axles on my MTB trucks

You mean that the ends of the axle should be sort of like what I have on the extension? A small (M6) thread and then the bigger thread “behind” it?

What type of steel or aluminum do you recommend? Depending on the cost I’ll see if I can get a few sets made for testing. What about titanium?

Leave the stock axle as is 12mm, no mod. Then you can have a a bar with a threaded hole also 12mm, extend enough so as not to cause a fragile interface then slope back down to 12mm with thread on the end.

You won’t get a any real gains from Ti unless replacing entire axle so down to how much you want to spend

The steel we use is the toughest steel the machines can work. That is one of the differences if you compare our gear to the stuff you can buy elsewhere. If you extend the axles further try to go for e.g. 42CrMo4 steel, something really sturdy! Getting the originals out is possible, but can be a painful job, depending on the tools you have to hand. They are press fitted. The grub screw is just another safety feature. I don’t think that the extensions will work. They will probably snap very soon. You will need to machine new axles and replace the originals. Be prepared to waste a hanger.


If I understand correctly, that means extending the axle even further in order to accommodate the slope you’re talking about, as well as the area that will take the hubs themselves. I dunno… @trampa another alternative might be to remove the bar and tap the resulting holes for M12, then have custom-made shoulder-screws with extra long threads serve as axles.

A shoulder screw schould be tough enough, but a 12mm OD shoulder screw has a M8 thread, not M12. And M12 needs a smaller bore to cut into.

How much smaller? Or, since the hole for the axle is already M12 I simply design for M14? I’m expecting to have to design a custom bolt with the correct width and thread, but this will still be easier, since it’s one part rather than a system of axle + extensions. Take a look at my parallel thread on this, you can see that the wheels there also had one bolt each, serving as independent axles.

The hole is about 11.9mm. If you have them out, you can stick in new ones, sanding them down until they slot in without any play. You can then use the strong loctite to secure them. If you can lathe them to the shape we use, you can re-insert the M6 grub.

That could work… I’ll have to see what lengths are available or else start working on my own. The main issue seems to be making sure it goes deep enough.

Inerested to see how you went pulling out an axle. I’m going to make some custom axles for my street carvers that accommodate a pully bearing and probably 8mm axles. How much heat is required? Gentle heat gun or strip the paint blowtorch?

hello. do you find answer?

Did it with a heat gun and a big slid hammer. No damage to the truck or the axles. It did take alot of force tho so if you have access to a press that can pull I would use that.

This guy did a really good job. It’s not easy or cheap but probably the best solution. https://www.electric-skateboard.builders/t/the-fat-spud-jet-spud-29-deck-trampa-trucks-10-wheels/90979

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