New to truggy's - and not real impressed so far - RC-Monster Forums

JThiessen · **New to truggy's - and not real impressed so far -** 08.06.2009, 09:10 AM

Some of you may know that I recently converted an 8T 1.0 using the Tekno kit (long shank pinion set up). I pulled the MMM/Neu 1515 2.5D out of the Revo to use in it, running it on 5S Neu 4900.
I'm geared at 16/47
Center Diff is now fresh with 50K - I havent pulled the front or rear yet.
I had it out for a few minutes last night to just run it up and down the street to get a feel for the gearing and check temps.
Anyway, I'm less than impressed with the off the line pop, acceleration, and overall feeling of speed. This is in comparison to the way my Revo ran with the same motor, my Flux (maybe not a fair comparison), and my past Maxx's and other rigs.
I dont recall what my settings on the MMM were - but I know I have never turned down the punch control more than 10 to 20%.

Is this "normal" for a truggy? What steps does one take to give it that "out of control" acceleration feeling that we are all so attracted to? I assume that going up in diff oil weight is the only mechanical tuning solution - besides gearing. BTW, with the Tekno set up, and the 47 tooth spur, it looks like 14 or 15 is the smallest pinion I can run - my 13 wouldnt engage. I do have a 48T Robison spur that I can put on there also....

brushlessboy16 · 08.06.2009, 09:13 AM

Have you considered that the truggy is just accelerating efficiently? Might looks slower because it doesnt yank the front wheels. Also the center diff could be unloading..

08.06.2009, 09:27 AM

sounds like he center diff is unloading on you

Kcaz25 · 08.06.2009, 09:34 AM

"out of control" is not what the truggy is about.

How are temps?

wallot · 08.06.2009, 09:36 AM

whats the diff ratio in the 8T?

50k is too much

I run 20-20-5 in my truggy and I am limited just by traction as far as acceleration goes.

BrianG · 08.06.2009, 09:53 AM

Your acceleration is being limited by your CD. If you like the way a MT/Revo accelerates, either lock the CD or put much thicker oil in it. I personally like 120k+, but I'm not a racer either.

nitrostarter · 08.06.2009, 09:59 AM

Definitely a difference when going from tranny's to CD's....

brushlessboy16 · 08.06.2009, 10:01 AM

Quote:

Originally Posted by nitrostarter

Definitely a difference when going from tranny's to CD's....

Is that what she said?

the wheelie inducing high center of gravity and short wheelbase of Mts is probably giving the illusion of bettery acceleration.

RC-Monster Mike · 08.06.2009, 10:24 AM

I agree with brushlessboy16 - the truggy with 50k is likely faster and quicker than the MT, but the low Cg, extra length and controlled fashion in which a truggy gets the power to the ground makes it "appear" slower. Lock the center diff, install stiff springs with lots of preload and lighter weight shock oil, heavier diff oil all around and disable punch control(basically detune the truggy) and you should get a more sketchy, out of control feel. Or.....utilize the enhanced handling capabilities to allow even more power! :)

Kcaz25 · 08.06.2009, 10:36 AM

Yep.

Glad to see you posting Mike!

JThiessen · 11:26 AM

Quote:

Originally Posted by Kcaz25

"out of control" is not what the truggy is about.

How are temps?

And I've kept that mindset so far - hence why I'm asking if what I'm sensing so far is "typical" difference between truggies and MT's.

Temps were very cool - but ambient temp was about 60 and I only ran it for about 5 minutes or so. I suspect I can gear for higher speed and not have an issue.

Quote:

Originally Posted by BrianG

Your acceleration is being limited by your CD. If you like the way a MT/Revo accelerates, either lock the CD or put much thicker oil in it. I personally like 120k+, but I'm not a racer either.

I agree that it would likely be faster on the track - but I'm like Brian - I've never set foot on a track so far (dont even have one within 30 miles of me - seems everyone in Seattle is a carpet racer), and just trying to wrap my brain around the nuances of these center diff systems.

I do like to have the ability to run on the edge if/when I want. I dont like wheelies so much - which I why I wanted to try a truggy, and to get a feel for thier durability compared to my MT's.

I'll stop and pick up some heavier oils to try, and double check my MMM settings. After reading through the link someone posted about diff set ups, if I run up to 100+ on the center, what I have in the front/rear doesn't really matter (within reason) except for tuning the cornering, right?

I also have an RCM mount for it. However with the layout of the Tekno chassis, it looks as though I would need to mount it "backwards" to keep the motor in the right rear corner. The motor fastener heads wouldn't be in the slots in the mount, but other than that, anyone know if having the mount backwards would cause any issues? The only reason I'd throw it in is to give myself the ability to drop down in pinion size (better acceleration, right??)

BrianG · 08.06.2009, 12:26 PM

Yeah, like you, I mostly bash. Even when I do play at a track, it's not at an actual race, just play. I too wanted a vehicle that was lower sprung, more durable, and more easily fixed (easy disassembly), but with monster truck usage. I find that 120k CD oil allows for great acceleration while taming the wheelies. Also help reduce front wheel ballooning. I can still wheelie if I want to, but I have to try.

lincpimp · 08.06.2009, 12:52 PM

With the 1521 1y 6s powered muggy I use a mixture of 50 and 100k in the CD. Ending up with something like 75-80k. That works alot better than the 50k did, and still allows for tight turning (on higher traction surfaces). I run 30k in the diffs, but I also run heavier tires and wheels, so I need thicker fluid to keep from diff-ing out. I mainly run on the road and thru grass so thicker fluid benefits my environment.

Comparing the muggy with the lst (about as close as you will get as they share almost everything save for the chassis) the Muggy does feel much more planted, turns alot better, and jumps almost as well. Either will show up a maxx/revo during bashing, just no comparison. The lst is more "fun" as it is a bit taller and will flip easier, so it keeps me on my toes. Tire selection makes the biggest difference.

BrianG · 08.06.2009, 12:55 PM

As far as turning with a locked (or very thick oil) CD, I prefer the method where I apply the brake while turning. On grass or asphalt, this results in the truggy just about pivoting around on the inner front tire.

nitrostarter · 08.06.2009, 01:20 PM

Quote:

Originally Posted by BrianG

As far as turning with a locked (or very thick oil) CD, I prefer the method where I apply the brake while turning. On grass or asphalt, this results in the truggy just about pivoting around on the inner front tire.

Thats they advantage of the 3 diff setup. I was able to do this with both my buggy and truggy and able to spit out faster track times.

The truggy was fun but not for me. I enjoyed racing my buggy MUCH more than the truggy for some reason. They just seemed a whole lot quicker all around and more durable.