Raman

iTrader: (94)

I had it NIB.. need to paint it. It looks like it has more detail than the Tamiya one.. shame they didn't allow for a abs / chromed grill like he Tamiya one.

4roller

All this sudden influx of talk about the xv-01 got me wanting to drive my car again.

I have 2 xv-01s. The second one is a rebuilt chassis bone stock that I got from eBay. It needed all types of fixes. The first one is upgraded and modified. I've had it for over a year and half now. I've beaten on it pretty hard. So remember when I was driving with big 96mm tires? And that clicking sound I mentioned, thinking it was the rear belt pulley? Well it could have been, but the more real culprit is the front gear box. Today I went out for another big tire mash through the back yard in grass and rutty terrain. Click click click on hard accelerating and hard braking. I decided to pull the front transmission apart.



The idler (left) and the counter gear (right) are a little chewy the from abuse. I run a slipper clutch but even then, with a 13.5 motor and maximum oversized traction, the counter gear has started to eat itself. The counter gear is basically where all the torque goes to directly off the spur.

Anyway. I ordered up some gears, hopefully I can rebuild the xv-01 soon.

I'll have to run the slipper mighty loose when I am pretending to be a monster truck.

Whizzzzzzz.

fyrstormer

iTrader: (1)

Uh, did you grease those gears at all?

4roller

I greased them like the manual said to. Mostly on the diff gear which spreads to the rest of the gear box

Raman

iTrader: (94)

With the amount of hard running you're doing, those gears will eventually wear, especially with those larger diameter tyres.

I highly recommend finish line ceramic dry wax for those gears, instead of grease Tamiya suggests.

https://www.amazon.com/dp/B0022KK92A/ref=cm_sw_r_sms_c_api_odeSzb127Y72F

Shimmy

iTrader: (19)

I run a 13.5T and only a light coating of grease (the supplied one from memory), no gains to be had by having them bathe in it.

The only issues I've had is the stock pinion and spur wore out in about 30 or so packs (replaced with 48p)
Front axles shattered and broke apart in the cup from the dog bones (replaced with Tamiya CV).
And now the diff output cups are doing the same, severely worn and about to break.

The belt, belt pulleys, and internal gears have been good so far, I have spares ready to go I think, including a reinforced belt but the standard one seems to handle a 13.5t good enough.

I don't treat it nicely either, I'm hard on the throttle with it.

I'm only running TC and "rally" sized tyres though.
I'd hate to know what else I'd break if I had bigger and heavier tyres.

4roller

The new set of gears came in the mail today. You can see the gradual wear that has happened over the last year and a half. The outer diameter is smaller on the older gears.

On a similar topic, I rebuilt the front gear box. I found a lot of the old high weight (60k) differential fluid that leaked out got onto the gears and inner casing. Since it's silicone it's damn sticky. So sticky that it actually impeeds the rotation of the gears. After cleaning it all out and using a very light oil (triflow) it's nice and free spinning now. For those that recall the winning RC10 from 20+ years ago, that gearbox was put together by a machinist who said he could have gearbox spinning for 10seconds. My gear spins for a second or so. But it's waaaay better than it was before. Less mechanical drag means more power to the wheels.

Anyway. The transmission after being rebuilt definitely feels smoother for acceleration and coasting.

SerpentCT4S

iTrader: (95)

Hey guys. I'm building a new rally car, but it's not an XV-01. I'm just curious, what type of diffs do I need for a rally car? Currently the chassis I'm using has a front ball diff and a solid rear axle. Any help would be great!

haplm

It kind of depends on your driving style and surface. We are racing mostly on gravel, and people typically use either gear differential on both ends, or gear in the front, and ball in the rear.

The idea is, that rear needs to be as "light" as possible. If you will use gears, put very light oil (something 900cSt) in there. Tune front to your driving style. I'm using around 5k oil, but I know people who are using 40k on the same track.

Unfortunately the Tamiya diffs are quite leaky, so I recommend to use the TA06 Aluminum Differential Unit Cover #54602, and Kyosho ORG05 Silicone O-Rings, which fix the problem at least a bit.

SerpentCT4S

iTrader: (95)

I'll probably just be using mine on pavement and dirt, like baseball fields.

With that be said, what should I run front and rear? Currently I have a ball diff in front and a solid axle in the rear.

Mr_RCGuy

Hi All,

I have read all 104 pages and wow, a ton of good information. Thank you all for sharing!

Boring info about me: I race an M05 and always wanted to race Rally. (Still trying to get a race club going.)

I am impressed with how strong the Tamiya M05 and XV-01 kits are. I pulled the trigger on a XV-01 Long Damper Spec a week ago and building it now. I am blacking the chassis and bits out as well as the blue aluminum parts. I won't be dumping all kinds of power in the XV-01, but it should run strong.

I will be posting pics of course.

Take care,

4roller

Awesome! Another xv-01!

I think the internet really helped me decide on getting one, this and the RC crawler threads.

4roller

What chassis do you have?

I would go with haplms suggestion. Diffs at the front and rear. Loose diff in the rear, thicker/Tighter in the front.

You can run either ball or gear diffs it doesn't matter.

4roller

A lot of times before I had my Ta05 and Tb03 I'd run my xv-01 in street mode. 8mm ground clearance. And stiff springs. It ran pretty well once everything was dialed in.

However it really sucked offroad. It would always get caught up on slow grass and bits.

Now that I have dedicated road setups, I can concentrate on rally setups with the xv-01. Being that rally is very much a multi surface type of discipline. At first I raised the car to 20mm with Stock springs. It could handle the grass and rutty-ish terrain very well. But on the street it would fail because of the chassis roll. It looked cool a realistic. Like a Full sized sedan trying to run the track. But handling on road with high ride height and soft springs is terrible.

So the other day I set up the xv-01tc to 19mm with a max droop of 22mm (f/r) I put the firm road springs on. Blues up front and reds on the rear. The car can still handle the grass and rutty-ish terrain. And now on the street it doesn't flop. I am guessing the stiffer springs would be good for jumping too.

I dialed the camber on all four wheels to be zero degrees while sitting at the 19mm. I get good traction on the street while on the straights and corners.

Spring rate is really important on road. Not as critical off road.

Sure it bounces a little more off road (no soaking up bumps as quick as soft springs) , but it's way better on road. And since rally is a multi terrain discipline, we want to have the best of all worlds.

SerpentCT4S

iTrader: (95)

I'm using an Overdose XEX for this rally build.

Currently it has a ball diff in front and a solid rear axle. So I guess I'll grab another ball diff for the rear.