Tamiya Manta Ray & Mad Bull

[m38joe]

A few weeks ago, I bought a new Tamiya Mad Bull kit for my son's birthday and a bunch of old rc car parts. I loved my RC as a kid and hoped that my son, would feel the same. He's really taken to it! We've had a blast putting things together and seeing what we can get running again. We still have a lot to do... We're hoping to get enough cars running, so that my son and his 3 best buddies and myself, will have a car, to play with.

Here's a picture of an old Manta Ray. This one was running & is fun, but is currently downed while we wait for some replacement parts. I don't have the Manta Ray body, but do have a VW Baja clear body, that my wife is going to paint for it.

[m38joe]

and here is the Mad Bull, that my son put together w/ very little help from me. This thing really seems to be able to take a beating My son loves it and is currently planning out, how he's going to paint it.

[Coelacanth]

Nice job of your son building the Mad Bull...but you'll want to swap the rear wheels L to R because your front & rear tire treads need to be pointing the same way.

[m38joe]

They are just placed for the pic my bad... Waiting for new drive hubs.stripped because of loose wheels.oops! He's learning.

[m38joe]

tires fixed

[markbt73]

The old Manta Ray / Blazing Star / Dirt Thrasher is a great runner. One of Tamiya's better 4WD buggy chassis. It does need one or two little things to bulletproof it: replace the weak aluminum pinion gear with a steel one from Robinson (they are 0.8 module metric gears, sold as "metric 48 pitch", regular 48 pitch gears will NOT work), and for a little added insurance, replace the plastic motor mount with an alloy one.

Pinion gear: http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXEX40&P=SM

Motor mount: http://www.rcmart.com/yeah-racing-ta01013bu-alum-modified-motor-mount-1621t-ta01ta02-p-27517.html?cPath=595_744_754

Tip on searching for parts: all the drivetrain and gearbox parts of this car are interchangeable with the TA01 and TA02 touring sedans, as well as the DF01 chassis (most commonly sold as a Hummer).

[m38joe]

We put bigger wheels on it.. and burned up a motor.I didn't change the gear ratio.I'm still learning then I bought three different gears to get the right pitch.. and waited for a new engine mount for a week.still needs some steering work.It'll get there sooner or later.

[kaiser]

get some buggy tires/wheels back on that manta ray and you'll have a great runner, one of my favorite tamiya's.

[m38joe]

get some buggy tires/wheels back on that manta ray and you'll have a great runner, one of my favorite tamiya's.

I started with stock buggy tires and it got stuck in short grass and my son kept running over it with his madbull
I dropped the pinion gear to a 17tooth to account for the bigger tires and it did a lot better this past weekend.

[Coelacanth]

Don't forget that running in grass is probably the hardest thing on motors for overheating. If you run in grass, check your motor temps and downsize your pinion gear until you're comfortable with the running temps.

[m38joe]

so...

I have gone to a 16t pinion with the larger tires. The car runs good and cool,but now I have broken two dog bones? I have read these were kinda weak. Is this a large tire issue or a torque thing with the gearing or just need stronger bones?

[kaiser]

those stock bones stink, they have plastic ends. IIRC they are 70mm, so most tamiya cvd's / uni's will work.
gpm, yeah racing and 3racing all have cvd's that will work. df02's bones are the same size so if you search using the term df02 you may find more results.

you may also want to upgrade the prop shaft. i use a yeah racing unit. because once the dog bones / cvd's are upgraded that tiny wire prop shaft will let go next.

[m38joe]

those stock bones stink, they have plastic ends. IIRC they are 70mm, so most tamiya cvd's / uni's will work.
gpm, yeah racing and 3racing all have cvd's that will work. df02's bones are the same size so if you search using the term df02 you may find more results.

you may also want to upgrade the prop shaft. i use a yeah racing unit. because once the dog bones / cvd's are upgraded that tiny wire prop shaft will let go next.

I did some looking on the df02 they appear to be 64mm?

What's the difference between a cvd/uni?

I'm only 2wd right now, that's all the parts I have left... What should I order? anyone? from USA?

[kaiser]

hmm....

it's been a while since i looked for them. on ebay they had them listed by vehicle but also with the lenght info.

asiatees.com also used to list them but no longer do.

i need another set....i'll go searching.

[Coelacanth]

What's the difference between a cvd/uni?

U-joints:



CVD's:



Functionally, they're constructed quite differently. CVDs are smoother. U-joints are susceptible to binding as the angle increases, not CVDs.