Top Force Evo drivetrain issues.

[Tomas Karlsson]

well...

Was supposed to race this one but have some big issues with the front driveshafts when fast cornering. I cant tell exactly what it is but i guess the outdrives pops out of the diffs or something like that. I use two o-rings in each outdrive, The lack of good steering geometry is also a big problem, the knuckle arm binds in full steering and make the inner wheel wobble. i have no clue what to do but i really need to get rid of this problem.

Is there anyone that experienced this problem before?

Thanks for all kinds of input.

//Tomas

[fakiee]

TamiyaDan is your man!

[Tomas Karlsson]

ok i´ll wait to see when he jumps in to give me my life back;)

[DennisM]

Who told You that a Tamiya can be used for race in the first place

Edit -
Checked the steering on my Top Force std.
The main reason for the sloop on mine, is worn out brass bushings on the steering pivots.
And if the pivots are made of aluminum, I guess they are worn too.
One fix could be ball bearings instead of brass bushings and new stands if they are worn.

[Tomas Karlsson]

Hi Dennis!

I use ballbearings in the steering linkage, so i guess that is a minor problem.

I getting angry the more i think of this crap...

[EvolutionRevolution]

Are you using the stock plastic hexes? If so, swap for aluminium ones, as they will melt and deform under performance and bind up the wheels.

[Tomas Karlsson]

I use the aluminium hexes all around.

The steering has some weird angles so the linkage have a deadspot, i want to move the steering more forward so i gain more angle towards the knuckles.

But he biggest problem is the noise of rrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrr or brak brak brak when high speed cornering..the driveshaft just locks up and acting really weird, or the outdrives or something else..

[DennisM]

Try mounting the ball stud in the steering knuckle´s inner hole.
And set Your EPA to the point just before the steering goes bananas.
How about the servo saver - Is that the original sloppy Tamiya one?

[tamiyadan]

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[rccars4sal]

I seem to remember that even ta01 with ball diffs will have the same problem. The front geometry allows too much angle in the u joint at the knuckle with full steering lock. In a ta01 anyway, this would pull the swing shaft away from the diff outdrive, and also cause the u joint to become tight as it turns. Thats why MIP invented CVDs. How I dealt with it, I installed the 1 way front bearing to increase front traction off throttle, lowered front end slight to increase front traction, and reduced steering throw so the u joint wouldnt bend too sharply and the diff out drives wouldnt pull out and wobble. In short, you may have to find more steering without increasing steering throw.

[Tomas Karlsson]

WOW!

Thanks for this inputs guys!

Will try some stuff next time. Maybe in B/S/T section...let´s see;)

[EvolutionRevolution]

when you tighten down "Tamiya" rims to the axles, you use a very light hand, just snug the wheel nuts down then 1/16-1/8 a turn more max.
the lock nut is what holds things together not how much you crank that nut down.
that is why the plastic axle hexes, crack/melt/warp. the metal ones are fine, they just weight more and give you a false sense of security to crank down those wheel nuts even more and warp the rim.

Dunno whether that is always the case. I generally do not crank down the screws/nuts on my Tamiyas because it causes things to break and check whether everything is smooth, but on my Blazing Star I lost a wheel while running in +30 degree C conditions because the plastic hexes decided that getting wider and pushing off the wheel was a good idea.

the steering tolerance/play.

first off all tamiyas regardless of how new or worn things are have lots of play in all the suspension and linkage parts.
many people try to correct this because they are used to seeing everything tight in a steering and suspension they believe it effects the precision of the chassis.
in some cars it does, not in a tamiya. you want that slop and float in the suspension and the steering. when the car is moving it all equals out and allows give in a crash or when taking a jump. if a car is floating too much then you get wandering in that case you look for mechanical damage.
otherwise build it as tamiya designed it and leave it alone.

This may be correct for the Top Force (Evo), but is wrong for every other DF-01 Tamiya car (Manta Ray, etc.). The stock servosaver has tons of play and you just won't be able to steer straight while using it. The stock bellcranks, linkages and pivot balls wear out really quickly in dusty conditions too. At least, that's my experience while backyard bashing. Most annoyingly, the stock red front uprights crack at the kingpin holes after a while - this appears to be a plastics issue, as I've had brand new front uprights with cracks.

[tamiyadan]

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