# TT01 Ball diff questions



## CreativeIndy (Dec 1, 2011)

Is anyone running the ball bearing diff Tamiya makes? Tamiya #53663. I believe the setup process is identical to that of the Tamiya 416,417, F and M chassis ball diff's but I can't verify this as fact only heard it was.

I bought this back when I first started running TT01 at LHS and I built it just like every other ball diff. The difference with this one and almost every other on market is there is no adjusting it. Most make you tighten down, run the axles at speed, re-tighten and re-run over and over in an attempt to seat the bearings or create a groove. This isn't the case with the TT01, instructions say to just tighten all the way.

The TT01 there is no slight tighten, it's either all the way down or extremely loose. If you don't tighten all the way down the 2 ends wiggle badly. Even if ou tighten all the way down and back off just an 1/8 of a turn the whole assymbly is pretty loose. 

However if you tighten all the way down the action isn't too bad, however there is some considerable amount of drag present which you could compare to a drag brake set at say 25 to 30%, but there is no grinding or anything of that nature. There is no bumps when spinning the diff like you would get if you over tighten say an SC10 ball diff. You turn and you get that bump or click type feelings where you can feel every bearing you rotate past due to over tighten. None of that exist in the TT01 when tightened all the way down.

So I was curious if anyone else is running the ball diff and maybe I missed something, a spring or something? I installed every part it came in the packe with nothing left over. The intructions simplay tell you to tighten it all the way down. I just can't get past there is no seating process and the considerable amount of drag it produces. 

With the drag that is present when chassis is back together and it's ran you can tell it's a considerable difference in speed compared to gear diff. The ball is quite a bit slower and if I had to guess I would say upwards of 30% slower than gear diff. 

Anyone have any experience with the TT01 ball diff please feel free to share some tips or pointers. 

Thanks.


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## CreativeIndy (Dec 1, 2011)

On further note, I have ran this 2 times in 2 nights of racing a few weeks back. I tore it down today to make sure there was no burs, knicks or damage if it was possibly over tightened. The inside looks just as it did the day I pulled it from the package. There are really no grooves I can see by my eye, the bearings seem to roll great. There diff grease wasn't burnt or badly discoulored from heat from over tighten. I just can't believe this is how these are supposed to be built and ran with this much drag due to no adjustment or backing off after tighten down.

If you google or look on the picture of the ball diff you will see there is no springs in the parts so back pressue is non-existant.


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## CreativeIndy (Dec 1, 2011)

Hrmmm all the talented individuals on here and not a single person has any experience with ball diff's in any of the Tamiya cars or trucks???

Guess for technical issues I will have to go to rctech. Seems to have a lot of technical people, just have to deal with the kids on there as well.

Gah


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## DaveCook (Oct 13, 2010)

I am not familiar with the #53663, but the Tamiya #53267 for my Mini has a few "disk springs" on each side of the thrust bearing that have to be installed in the correct position so that they work like springs rather than stacking on top of each other. I do not know if your diff has these or not, but I thought that I would mention in case that it does.


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## CreativeIndy (Dec 1, 2011)

This one has 1 of those as seen in the pic below. However, it doesn't have much "Spring" feel to it. It's like if you don't tighten the diff all the way down it basically rattles because it's loose.


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## HPITim846 (Feb 18, 2011)

You might ask here...... Someone in there should know.
http://www.rctech.net/forum/electric-road/93146-tt-01-forum.html


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## CheckMyBrain (Jul 15, 2011)

CreativeIndy said:


> Hrmmm all the talented individuals on here and not a single person has any experience with ball diff's in any of the Tamiya cars or trucks???
> 
> Guess for technical issues I will have to go to rctech. Seems to have a lot of technical people, just have to deal with the kids on there as well.
> 
> Gah


From what I found from reading not many people actually use the ball diff, which is kind of surprising.


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## CreativeIndy (Dec 1, 2011)

CheckMyBrain said:


> From what I found from reading not many people actually use the ball diff, which is kind of surprising.


Yea I am getting that impression to...oh well, gear diff works I guess just sucks at 45.00 it doesn't operate any better than this.


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## Railroader (Jan 2, 2008)

CheckMyBrain said:


> From what I found from reading not many people actually use the ball diff, which is kind of surprising.


Actually, if you think about it, a gear diff is better to run. There is virtually no slip, and you can tune the diff action with different viscosity oils. *ALL *the faster guys I know run with gear diffs, and my laps times in USGT dropped about a half second when I switched to a gear diff in the front (I will put a gear diff in the rear soon too). Seems to get much better on throttle take off out of the turns and mid corner off-throttle predictability is better.

The only consolation I can give for someone wanting to run a ball diff in a TT01, in a spec class, is that everyone has to run the exact same equipment as well. The gear diff may be better though. Not all hop ups are worth it or are even an improvement.


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## BadSign (Sep 26, 2001)

CheckMyBrain said:


> From what I found from reading not many people actually use the ball diff, which is kind of surprising.





CreativeIndy said:


> Yea I am getting that impression to...oh well, gear diff works I guess just sucks at 45.00 it doesn't operate any better than this.


A lot of people tried the ball diff in the mini and found it was no better, either. We just packed the gear diff full of grease. Might actually be a good option for the front gear diff on your Tamiya car

I haven't switched yet (using a solid axle front and ball rear), but I will be soon. The fastest drivers at The Big Rug swear by them- more steering, more traction, faster lap times


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## CreativeIndy (Dec 1, 2011)

BadSign said:


> A lot of people tried the ball diff in the mini and found it was no better, either. We just packed the gear diff full of grease. Might actually be a good option for the front gear diff on your Tamiya car
> 
> I haven't switched yet (using a solid axle front and ball rear), but I will be soon. The fastest drivers at The Big Rug swear by them- more steering, more traction, faster lap times


Yea I thought about that. Putting it in the front since the action on it was similar to a straight axle. I found that it made the rear end slide alot more coming out and into corners. I remember taking it around a few laps and couldn't get a feel for it or keep it under control so I tore it right back out as fast as it went in. 

I may give it a try again on practice day with some different tire combinations and see if I can get used to the driving with it in the front.


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## BadSign (Sep 26, 2001)

Try some thin shock oil in the rear- maybe 35wt with a soft spring, 50wt front with 2lb stronger spring.

What tire dope are you using?


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## CreativeIndy (Dec 1, 2011)

BadSign said:


> Try some thin shock oil in the rear- maybe 35wt with a soft spring, 50wt front with 2lb stronger spring.
> 
> What tire dope are you using?


I'm running 35wt already in the rear... quite possibly 30... can't remember which I last put in but it was one or the other. 

Paragon


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## BadSign (Sep 26, 2001)

What about the front?


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## CreativeIndy (Dec 1, 2011)

BadSign said:


> What about the front?


If memory serves I am running 45 in the front and Blue springs is the current setup.


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## BadSign (Sep 26, 2001)

If the track doesn't get much of a groove, Id try red rear springs and 35wt, 50-55wt front with a blue spring. If the car pushes as the night goes on, switch to a yellow front.

Also, if you can get some, switch your traction compound to Trinity Death Grip. The first time used it, I doped half the fronts and the car pushed. The next run I doped the full front tires and it gripped so much, the front end actually jerked the rear of the car loose. I stiffened the front way up to make up for it, and it was great.


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