i have a hsp warhead 1/10 buggy its is 4wd but when I rev it only the front wheels turn
also it is a 2speed but I'm sure it is staying in one gear and wont change any ideas please
I haven't looked at the rear diff I just replace the gear box and it seams to stay in one gear and only the front wheels turn
should I open up the rear diff and check the gears
You definitely need to check everything from the transmission back to the rear diff. Have you check to make sure the shift point is set properly on your 2 speed? I had that problem once and I had to tune my shift point. That was on an LST2 though....not sure if or how you would do that on an HSP model.
A common problem and one that is hard to spot, on the rear diff there is a cup that holds the dodbone ( to the center diff and rear wheels ). The cup has a grub screw that comes loose periodically. It can even work its way out. The grub screw is the same size as the one that holds the exhaust on its stand if you need an emergency spare. The gear change is not like the centrifugal clutch type, more a lever that pops out and strikes a pin on 2nd gear cog. Check this pin on the cog has not been sheared off.