Tamiya Astute

[Brandon G]

Well, to those who think I put hingepin bearings in just so I can shave a tenth off of my lap time, the jokes on you. This car will not be run on dirt, if at all. Just a buggy for me to give me personal satisfation in owning and assembling. While I respect those who have cut their teeth with racing this buggy, this is just a build. I understand what the bushings were intended for, and if they were at all tight in the moulded parts, maybe they would have achieved their purpose. If the bearing prices were at all like they were in the 80's, then I wouldn't have bothered. However at 50 cents a piece...why not? Just a little exercise in overindulgence.

[Delorean]

As always I love seeing Brandons builds and as a fellow builder and successful race of an astute in vintage racing in Australia I thought i'd add some info to the thread which I think has is marginally incorrect

My build thread : http://www.tamiyaclub.com/forum/index.php?showtopic=69225&st=0

Bearings were listed as an upgrade for the astute, on or around page 27 of the manual has all the listed upgrades including hi-cap shocks, the then 730 sealed ball bearings to replace the bm3 bushing which features in most of the pivot points of the car

Super astute was a jump forward for Tamiya, though the arms aren't madcap derived, they are a complete redesign, are different geometry and of a different material, they are super stiff and much better than the madcap or astute arms. The super astute was the first and only car to feature the TTC, given the small diameter of the diff, they worked out that in the astute, the diff couldn't act as a slipper as well as a diff without melting, so they put a gear diff in the TTC, and coupled it with a slipper, thus in essence making the diff bullet proof and adding a slipper. I still reckon this was overkill, however I've not heard any reports about how the super astute handled with a gear diff, given it was not a sealed diff that you could alter using different grades of oil, i'd imagine it wouldn't have been the best

The chassis flex is a big problem, the chassis was too thin and flexible, for my build I used a fibrelyte chassis, even then it flexed so I got them to make me one out of 3mm carbon fibre which helped a lot

Some sort of top plate would be a benefit, as mentioned, the front kick up/bulkhead is weak, but is strengthened a lot by the super astute brace, in the end, I just used that and the thicker chassis but a top plate from the front bulkhead back to the rear deck that has the body mounts would be ideal

I actually think the original astute tranny is under rated, even though in my build I replaced it with an A & L lethal weapon tranny ( I did this so the car would last for our 6 hour enduro), the standard tranny is lightweight, quite efficient and has a low C of G. its perfect for 540 racing. However it did need a more easily adjustable diff, though they did make it easy enough to pop it out the bottom hatch. It also couldn't handle big power and survive if the tension wasn't checked regularly. ok I get why people didn't rate it. In saying that though a madcap completed the whole 6 hour enduro with the standard gearbox intact

Sorry for the long read, having spent a year reading about and building my astute, i'm pretty happy to see when others give them a go aswell

[stickboy007]

As far as the bearings go, I have trouble seeing the problem there in comparison to bushings. Even metal shielded bearings do a reasonable job at keeping out dirt, but if you're paranoid about it, then you can use rubber or teflon sheilded bearings for all of the hinge pin joints. No matter, I would contend that a bearing with dirt in it is still smoother than a bushing, so it's still a net win in my view.

[Coelacanth]

No matter, I would contend that a bearing with dirt in it is still smoother than a bushing, so it's still a net win in my view.

Not to mention bushings will wear out much faster than bearings.

[tamiyadan]

.

[stickboy007]

I suppose this depends on the kind of dirt you were running on. I would expect the hard packed modern tracks to not pose a problem here, since the dust generation is relatively low. "Old" tracks were generally much loamier.

[Brandon G]

Some outside pics..

[stickboy007]

Nice touch with the Dyna Tech motor.

[Brandon G]

Finally got the body painted! I had it done the day before going up to the Vonats. Took it with me to see how it did in concourse. I was decaling the thing in the hotel room Saturday night after a long day of racing! Enjoy!

[fakiee]

That is a really nice build, love the original Tamiya electrics too!

[Lonestar]

the shizuoka-stamped (not made, eh!) electrics top it of superbly!!!

Awesome

Paul

[fristajlo]

That is a very fine example! Great work man
Hope to start restoring mine soon too. This build is great motivation

[DemZ]

I cant believe how advanced they were back in the day, that buggy looks as advanced as anything out there today. Awesome

[rctenracer]

Advanced ? Over engineered with all the bushings / bearings. The astute is classic . No buggy ever produced had as many bearings.

[Mr. ED]

I have to agree: it was more of an 'us-too' model than 'advanced' for the time.
Put it next to an rc10CE, Ultima pro, trx-1 or jrx2 and you see what the hype was and how the astute fit in.

Unfortunately the plastics weren't as good as on those competitors and if I'm not mistaken they still had the giant 32dp gears inside (just like the ultima, I know )
Did they have splined outdrives? Ifnot , I apologize, but I remember those being painfully bad designed.

On a more positive note, I do and did love the cars progress when compared to the less racing oriented predecessors in the stable; such as the Fox and Wild-one . And I sure still love the body shell