This is a basic break-down of the Baja 5B, this will show the Baja’s main features, show its weaknesses, and will give you a heads up for when you need to take this sucker apart.
The Baja 5B is a 1/5 gasoline powered buggy. Powered by a 23cc fuelie weedwacker style engine and controlled by a Futaba made TF-10 FM radio w/ built in failsafe. Real beadlock wheels with 24mm hex’s, aluminum threaded hyper-adjust shocks with dual-rate springs in the rear. A thick 4.0mm aluminum chassis supports all of this making a spectacular 1/5 scale platform.
I. Minimal Disassembly:
0. Picture only shows one side,
repeat step on the opposite side of buggy
1. supplied tool
2. take special care of small
parts (washers, spacers, etc), they are
easy to misplace and it is difficult to remember their place
4. indicates color coded markers on picture
The Baja is littered with Body clips, the body alone uses 5 (another 2 need to be removed to get the lights out of the way). The wing is held on by body clips, the spur gear cover, the gas tank the radio box, the roll cage, the skid plate…..all held on by body clips. Starting with the body, remove the 5 body clips holding it on, then remove the body clips holding the lights on.
Notice the stinger for the exhaust is removed, this will open up more power.
Next remove the body clips for the wing, and skid plate. You should have put the wing on from the factory so I’ll assume you know how to take it off. The skid plate, although very easy, went somewhat unnoticed for me when I got my Baja. It takes those side panels for the body off along with it and makes life 10x more simple. The body clip is located on top of the rear suspension brace (the purple thing). Although I didn’t have it on in this picture, you’ll know where to look. After you remove the body clip, bend the skid plate down and pull back and it will pop off. You may need to use force if your Baja is dirty.
The roll cage is pretty simple to remove, as is the spurgear cover. For the Rollcage, remove the four body clipsº (blue)⁴ and push down on the tab on the top of the rollcage (red) ⁴. The roll cage will pull right off after that. The spurgear cover Is just as easy to remove. Remove the 2 body clips on the backside of the cover (green) ⁴, you may need to twist the knobs on the front of the cover to get the right side of the body clip, needle nose pliers are needed for this. This should expose the spurgear.
II. Deeper In.
With the rollcage and spurgear removed, it is time to get the main components out of there.
Removing the remaining roll bar is relatively simple. There are 8 allen screws (all of them are 4.00mm¹) 2 of the screws are loc-tited in the engine and will need some considerable force². The rest are going into plastic and don’t take much effort. After the roll bar is gone make sure you unbolt the upper shock mounts (3.0mm¹). I took the gas tank, radio box, and engine out all as one unit, it is easier then disconnecting the fuel lines and linkages, so make sure you unbolt the brake linkage from the brakes (1.0mm¹) and the steering linkage (3.0mm¹). There is a single screw on top of the brake assembly that also has to be removed (3.0mm¹).
Remove the spurgear by taking the single e-clip off. Next, remove all of the screws holding the gear plate on (3.0mm¹). The plate will slide over the pinion, don’t even try unbolting the pinion unless you are willing to risk your tools getting that off. I snapped a high quality allen wrench trying to get it off. The last thing on the top of the car holding the engine on is a long, 4.0mm allen screw on the backleft side. It has a silver aluminum piece² around it and take special care to remember where that goes and that you don’t misplace it. Now onto the bottom, there are 3, 3.0mm¹ allen screws³. Remove all three screws² and now your engine should be loose. To remove the gas tank and radio box (to get them all out as one unit) remove the 7 body clips on top of the gas tank and radio box and it should all come out.
Rollbar is there for the pictures, it was removed during disassembly III. Shocks
The Baja shocks are a few steps ahead of the shocks we are used to, not only are they huge (picture shocks a little longer then Savage shocks and easily as wide as LST shocks), and not only are they threaded. They have something called hyper-adjust pistons. They can change viscosity (well technically the size of holes in the piston) without removing disassembling the shocks. To do this, take the shock off the Baja², remove the spring and peel the rubber boot inside out. Then fully compress the shock and then twist it and you will feel it click. Clockwise to make it stiffer, and counter clockwise to soften it up. Peeling the rubber boot back is a little tedious, use needle nose pliers carefully, one side at a time.
Tip: take note, the bottom cap can be removed (use pliers) so you can remove the shaft with the piston still attached. Lifesaver when removing/installing the piston.
IV. Brakes and Differential
The Baja’s differential, transmission, and dual disc brakes are pretty overbuilt for even the Baja. At least, for the stock engine, provided you still use the stock engine. These shouldn’t have to be touched unless the pads need to be changed (I estimate once every 1 year, being generous). Removing the differential is not the easiest thing to do, and I never got to opening it up as I lost the patience to do so by about this time. To get to the diff, you start by removing the 4 counter sunk screws (3.0mm¹) holding the rear bumper on. Make sure you don’t lose the M3 nuts that the screws threaded into. Remove the upper hingepins (these are free after the rear bumper is removed, no e-clip). Now remove the 4 3.0mm countersunk screws holding the shock tower on and the 2, 3.0mm counter sunk screws holding the purple upper deck on and the 2, 3.0 mm screws going into the brakes. Lastly remove the 4, 3.0mm countersunk screws going into the bottom of the diff. the diff and transmission will be free after this. This will also get the brakes apart in the process. I don’t have any pictures of this as I have never done it.
Did you know: The Viscous Torque Control Diff in the Baja uses limited slip pads that will lock the diff during a diff unload. This is like a Posi Diff in a real car. This makes it so both rear tires will get the same amount of power when there is low traction but the diff still functions when it needs to. HPI also holds a patent for this and 2 other parts on the Baja.
V. Front Supension
The front suspension is another thing you will probably never need to touch. Being a 2wd, not too much is happening, standard independent suspension. As with most 2wd’s it has a pretty extreme caster for better on-power steering. Make sure you keep an eye on the e-clips for the hinge pins though; in hard, awkward, crash’s you may break some off (I know I did). Also, the front hex’s are held on by single e-clips (and that’s it) and this is what happens when you hit solid object with one of the front tires.
You don’t exactly have to keep an eye on this because I hope you’ll notice when one of the tires are missing. This seems more like a crush zone then a weak point, as it only destroys the e-clip and not anything else (id rather that then rip the suspension arms off the pins of bend a shock shaft). HPI includes a few extra of these e-clips. Replacing these involves taking the 3.0mm button head screw going through the bottom of the knuckle (Red) ⁴ and M3 nut (Blue) ⁴ its threaded into, then having fun with some needle nose pliers getting a new e-clip on the hub.
VI. Little Tips, that go a long way
This spacergoes into the bottom of the engine, it’s a big spacer for one of the three screws. Don’t misplace it with this spacer which is shorter and shaped slightly different. This is a spacer that goes into the side of the engine on the left side, for the rollbar. Mixing them up means the spur gear plate, gear meshing, and anything mounting to the engine wont line up, and give you Baja building hell.
This big spacer, goes into the plastic brace (on the crankshaft side of the engine) that carries the bearing on which the clutch bell rides on. It goes small end first into the top right hole.
Use a good allen wrench for the engine mounting screws and of course use threadlock. The 3.0mm allen wrench isn’t all that great. It would be a lot better if you grind the tip a little off, for some reason the very end is a little rounded off (not a ball tip) and it makes it difficult to use. If you have your own tools, use them. The tools you should be using (that came with the Baja) are the wheel wrench (which also adjusts tie rod ends and removes shock caps) the 4.0mm allen wrench, and the silver multi-wrench (for god knows how many uses, for example, it fits around shock bodys for tightening and removing of shock caps). There is also a phillips head screwdriver/dual socket wrench, one of the sockets is for removing the sparkplug. The phillps head will work fine on Phillips head screws, if there were any on the Baja… VII. Conclusion
That just about wraps it up, This should get periodically get updated as I find new things, and venture into other parts of the baja (more details on the Diff and tranny, and the radio system will be shown when I get new gears for my steering servo). Thanks for reading!
Jet-Pro Tuned Pipe (if you desire a snappier Fuelie)
Metal-gear conversion for steering (If you hit too much stuff, you may strip the plastic gears)
Stability Control (This beast is scary to drive sometimes)