Titan - Weak Differentials

[titan1]

I just bought an OFNA Titan about 2 weeks ago. I really like the truck but I stripped both front and rear differentials. I noticed the front wheels where not pulling because the truck would spin out very easy. I still had about 1/8 of a tank of fuel left so I thought I would run it on out. Before the tank ran out, the truck stopped pulling all together. After disassembling the differentials, I found both the front and rear differentials stripped. I looked in the manual and saw that OFNA offered an optional hardened gear set so I tried to order the optional gear set and found that they are no longer being offered. Now I am really getting concerned because when I called OFNA, I was told that more than likely they would not be offered ever again and that the Titan was not made for jumping and that is what will destroy the spider gears. When I stripped the spider gears, the truck had been coming off of the ground about 12"-14". When it would come off of the ground, I was as careful as possible to get off of the throttle to keep the engine and drive train from over revving. I am wondering if anyone has any suggestions about upgrading the differentials?

 

[Çh®i§tiªñ]

Isnt there a slipper gear on that truck? That should help.

About the diffs though - I would rebuild with the stock setup and see if by chance your LHS has, or can order, shims. The big thing with diffs is how well they are shimmed. Chances are their Q/A didnt take that into considerration. But I can't believe that any MT would not be made for jumping. Almost all off-roads should!

That sucks man! Such an expensive truck to boot!

 

[SilentHunterKellen]

Christian, I thought you said the Titan was one of the best MT's out there? O well...the Titan is cool but my friends not gonna want it now if its not made for jumping. He doesn't like staying on the ground, seeing as he has a OFNA MBX.
[move]-Kellen[/move]

 

[Alein]

Hmm I am glad I had gone with the Savage as the Titan was another MT I was looking into. Sounds almost like they are trying to discontinue the support for the MT. Even though it's not very old at all. Seems stupid to stop making the hardened diff gears as they know the stock gears are to weak.

To also say that an MT is not to be jumped come on what are they on glue. Gee any average Joe with any off road RC is going to do jumps, hill climbing and out right good old bashing.

 

[Çh®i§tiªñ]

Originally posted by SilentHunterKellen
Christian, I thought you said the Titan was one of the best MT's out there? O well...the Titan is cool but my friends not gonna want it now if its not made for jumping. He doesn't like staying on the ground, seeing as he has a OFNA MBX.
[move]-Kellen[/move]

Not the best, just one of the coolest! Have you ever seen one??? If I thought it the best, I would own one hehehe.... For now, I'm all about the Savage.

But back to the thread. Yes, it does seem weird that they are starting to discontinue support. Maybe it was just ONE bad seed answerring the phone over there. But then why would they keep taking out 1 page full color adds? Makes no sense. Especially to stop selling the hardenned gears. Does anyone else make an aftermarket?

 

[titan1]

Thanks for the input. I installed a new set of the standard diff. gears. My LHS said to run diff. fluid instead of grease. I ran the truck this week end and I had no problems with the gears but I kept in on the ground. I am really hoping that OFNA comes up with a solution for the diff. gears. If not, I am going to cut my loses and go with the Savage because keeping a MT on the ground is just not fun.

Christian,
Yes, it does have a slipper clutch. The way it is designed allows only for it to be adjusted in one turn increments. I loosened it by two turns but it seemed to slip to much so I went back to the factory setting.

 

[SilentHunterKellen]

Christian, Yes i did se a titan run. Its freaking huge and cool but, i think if it had smaller tires, it could be way more nimble and speedier. I dont like how it sucks at jumping.
[move]-Kellen[/move]

 

[Blakedude409]

Have you ever seen the ofna video, they were jumpin that thing offa huge wall of dirt. Advertising the "huge jumps it could handle". And you called and they said you couldnt jump it lol

 

[Çh®i§tiªñ]

Precisely - I'm not buying it that its not intended for jumping. There are plenty of 'other' situations that would make the diffs respond the same way without jumping.

I'm telling you, it HAD TO BE a bad seed answerring that phone.

Maybe we should send them an email and publicly address the issue. We could let them know we are posting it in a high visibility public forum so we get the WHOLE scoop.

What do ya' think?

 

[titan1]

Yeah, I did email them but I still have not got a response. I have another question. I still do not have good braking on my Titan. I feel the servo does not have enough travel on the brake side. It came with an Airtronics Blazer radio. I have tried to adjust the servo horn and the trim on the radio but I still do not have much brakes. I went to the 1200mah 5 cell battery pack hoping that would make a difference but it didn't. I was wondering if I upgraded to the Airtronics MX-3, since it has end point adjustments, would that allow me to get the travel I need?

 

[Çh®i§tiªñ]

1 of 2 things.

1. It is possible the servo is shot (but last resort)

2. There should be an adjustment to tighten/loosen the brake. Being as some like a drag brake etc. Do you have a link to the manual? I might be able to figure it out for you.

The radio with EPA adjustments shouldnt apply here. While yes, sometimes you dont want the servo to over apply pressure, using it to increase servo travel should not be the reason, nor will it work in most cases. If you run a slide carb, EPA is very good to have! The Futaba 3PK and the JR XS3 are my 2 favorite radios out right now. While the Futaba is more expensive, it has made a big difference on the performance of my vehicles with all the options it has. Very easy to program too! Regardless, it shouldnt take a radio to fix this problem.

So now if we do the brake adjustment and it still doesn't work then we may need to consider replacing the servo itself.

While the servo is dead center, power on at both the radio and RX, trim set dead center, take the servo horn off and put it back on so it is applying a slight (very slight) amount of pressure to the break. Screw it back down.

That should be the easiest way to set it.

Let me know how you make out and if you have a link to YOUR manual for your version of the Titan and I will check out what type of linkage adjustments it has.

 

[titan1]

Christian,

There is an adjustment on the brake linkage. I did adjust the servo by centering it and then I removed the servo horn and positioned in back in a neutral position. I will try and do it again but allowing it to apply slight pressure on the brake. I will let you know if it works. Also, the titan can with a 45 oz. throttle servo. I believe that is at 4.8v. I installed the 5 cell 6v pack. I guess that might raise it to 55 oz. Is this a strong enough servo? I was thinking about upgrading the steering servo and putting the current steering servo on the throttle/brake. It is a 110 oz servo. What do you think? Thanks for all the help.

Christian,

I forgot the link to the Titan manual.

http://www.ofna.com/pdf/titan-rtr.pdf

 

[RC Jack]

Titan1, have you shimmed the gears in your diffs? The EK had this problem BIGTIME, due to the engine's power. Shimming helped, but, the gearcase was faulty and would expand upon accelleration and braking. In the instance of the EK, the only way around it was alloy gearcases. TTR did come up with a "band-aid" fix and that was to run 2 screws the full length of the gearcase, which was all well & good, but, it was expanding side-to-side, not front-to-rear. This might be happening to the Titan. But, shimming DOES help.