SMR 510RR

iTrader: (2)

Its hard to say, there are a lot of factors that would combine to make it an issue. Run them and see what happens. In the future the recommended connectors are bullets (4-5mm) direct to the pack so order SMC's inboard packs.

I thought that too until I drove it outdoors. It is a setup issue and a track specific issue, fast steep jumps will throw the rear end over unless you catch it quick its not really saveable because you can only bring the nose up so much. I think a simple oil change in the rear is all that is really needed, I did notice the rear of my truck bouncing when it landed on occasion too while the front was more controlled.

Anyone still having issues with this go up 5wt in the rear vs. what you are running and leave the front where it is and see if that solves the problem (or at least makes it better). Drop your truck onto a table from about 6" and watch how it reacts, both ends should travel together and go down the same amount.

Mizchief

Anyone have a good way of doing static weight distribution on this truck? I was thinking of making finding some camber or steering links I could replace the shocks with at the same length of the shocks when the truck is at normal ride height. then use the 4 scale method to set the weight balance. Just need to figure out how to replace the shock with a fixed rod, or lock up the shock somehow at a certain length. Maybe a shit load of o rings on the shaft?

Bcholka

Driving style will always be a factor--but for those that built their trucks per instructions (LOTS of people) they will have an issue with the rear bumper slamming down on jump faces causing the nosedive (due to too little pack) requiring a spring/piston/oil change.
It's been discussed hundreds of times through this entire forum.

HickamHatch

iTrader: (12)

Where is the cheapest place to buy one?

nanoverse

It shouldn't get down but absorb the drop like a wet rag.

mo

iTrader: (7)

I imagine they are pretty close to the same price most places. www.p1hobbies.com sells them for $399 but it you use my driver code MOBERLY2013, you can get a 1 time 5% off most all items. They are not in stock but P1 will have it drop shipped directly to you from the distributor, along with any other parts ordered. Also, order over $100 are free ground shipping.

SMR 510RR

iTrader: (2)

I order all my kits from Tower because with a supersaver membership it is always the cheapest. Current discount code is available for $65 off $400, I used it on the truck only even though it is $399 it still worked so it brings the price down to $334. It costs $10 to join for the year but you get free shipping the whole time and discount codes for orders from $100-$600. If you buy a lot of stuff you get more codes up to $1000 but its better to split the order into multiple pieces because the lower codes have better cost savings by percentage.

It must have saved me $500 or so up until this point and I am on my second year so it cost me $20...not bad at all.

Right, my point is that the front and rear should be balanced. If you go up from the stock springs to Pink Front Green Rear then the oil in the rear is a little soft and the rear end bounces. at least that is my experience.

cnk

iTrader: (9)

I just placed an order for one at RPPHobby.com for $344.99 shipped after using their $25 coupon code listed on their site. That's been the lowest I've been able to find.

BashemSmashem

iTrader: (42)

I ran the stock setup for a few months and didnt see this nose diving issue , though I have been running 4x4SCT's for a few years now so maybe I am used to correcting for it ?

I have went to heavier springs and the 8x1.3 pistons and it did seem better ...

Bcholka

+1

Cain

iTrader: (294)

on thing I noticed for the whole using timing on a 540 Pro4 motor at least on a Tekin 4000Kv, it helped a lot to help the top end I needd but keep temps down. It seemed like just going gearing only, the motor got to a point it just got too hot.

I went down on gearing a the time (different vehicle mind you, but the idea applies) about a tooth or 2 from what I recall, but used 5 degrees of timing at a higher RPM Range (I think it was about start of 5000 of so) and it made a world of difference. Temps went down to the 130s versus the 170s and I had the top end I needed, and torque too.


As for the pistons question, I probably would go with the Tekno's just to keep current with the Team setups, etc. But, the Kyosho's do work.

I really want to try the 1.4's x 8s depending on what someone can say about how pack felt with actual use versus the stock 1.2 x 10 holes.

Mizchief

The SMC's are back in stock. Mine shipped out today: http://www.smc-racing.net/index.php?...product_id=115

SC Shaun

iTrader: (2)

Sorry to hear that dude. But something was wrong in how you are using your RX8's. I say that with respect.
-------

Finally got the truck into running Buggy times on indoor highbite.

Mizchief

I killed an RX8 by shorting it out via how I hooked up a voltage sensor for my telemetry system. Was not pretty but at least I didn't kill anything else in my truck in the process.

justpoet

iTrader: (16)

OK, time to write the good ol' electronics post. We seem to have several newer folks in this thread that could probably benefit from it. So, here it is.

The first thing for electronics is to decide what you're trying to do and to choose the right parts for your application. While most people go and ask what the right motor is for a truck, or the right gearing with their motor is for the truck, they don't take into account the ENTIRE system. So, I'm going to briefly cover each section...though not in complete detail, or this post would be way too huge. Keep in mind that this is for track use, though the same applies to bashing. If you're on grass, there's more rolling resistance, so more power is needed to get the same performance, etc...

Since motor is the general answer people look for when they ask "What do you have in that thing?", I'll start there.

Motors:
There are basically 3 classes of motor that can be used in 4wd SCs (not including 8th scale only motors): 4 Pole 540 cans, 4 pole 550 cans, and 2 pole 550 cans. The first and last are ROAR legal. The middle is not but is the most common, the most powerful, and the most efficient. If you're generally on a small track, choosing a 4 pole is definitely the way to go, as you will get more torque and acceleration. If you're on a larger track, 2 pole is a reasonable choice if staying roar legal is of concern and you want much smoother power delivery, though in general is not what most people will want. Also consider that you should get the correct KV rating for your application, and that this can vary across motors drastically. For example, the Tekin Pro4 4600 vs the Pro4 HD 4300, the 4300 when only looking at kv would be slower, but it has so much more torque that it is actually faster and accelerates harder at the same time when they are geared correctly. In general if you don't know what's what, I would recommend something around 4000kv in a 4 pole for small indoor, and something 4600+ for large outdoor. There are obviously exceptions, such as the 4300 HD, as it can easily gear up more, but that's a good general guideline to start your research on which motor to get.

Gearing:
Most people completely ignore this until they have everything and then wonder why they're slow, or running too hot, etc. Gearing is as much dependent on the motor as it is on the vehicle as it is on the track surface as it is on the track design as it is on the ESC settings you use. To start with, use the gearing chart on page 1 of this thread as a guideline of ranges to have on hand to start from, then figure it out based on heat and desired performance on the specific track.

ESC:
Your ESC can't suck. I can't stress this enough for 4wd SC. A Mamba Max Pro or SideWinder SCT Pro just isn't going to cut it, it can't put out the power for long enough without heating up and becoming far less efficient, and even less able to put out the power needed. Will it "work"? Sure, it'll run...but it won't even come close to something designed to handle higher power output, and it'll probably not last very long in the vehicle either. The most common ESCs are the Tekin RX8 (Gen 1 or Gen 2 are both perfectly good) and the HobbyWing SCT Pro. Other 8th scale ESCs are often used, and some folks are using high end 10th scale ESCs with various settings adjusted on them. If you don't know what you're doing with electrics already (aka, if you're learning anything from this post), stick with one of the ESCs I just listed and you should be ok.

ESC Settings:
As a first rule in 4wd SC, you should do this to any ESC before starting your truck (note that they're all good tuning aids, but you should tune up from this baseline, rather than down to it). If your ESC has punch, put it at the lowest setting, if it has a % current limit, start at 40%. Turn off all dynamic/ESC timing, turbo, boost, etc. Set your LiPo cuttoff higher than default (3.4v/cell is generally as low as I would ever suggest).

Battery:
Even if you're running for short 5 minute runs and never longer, get a GOOD and HIGH CAPACITY battery. I run 7200mah "70c" SMC packs, put there are many companies making decent 7000+mah 2s packs. While "c" rating is important, it is unfortunately a mostly made up marketing number, and fairly useless to compare brand A to brand B. Rather than getting into the details of that though, there is an actual C there, it just might not be as high as the label says. The important thing to realize is in how you can get the maximum current output from a pack. The mah MULTIPLIED BY "C" and voltage is how you can find the output capabilities. So you'll find that a higher mah pack can more easily provide higher wattage for not just a longer time, but with less stress to the pack. This is due to both having a higher multiplier in mah, but also typically having less voltage sag, so the voltage multiplier stays higher as well. Unless you're running a lightweight setup with a 2 pole and lots of limiting, don't even attempt to use anything less than 6000mah for a pack. Going lower will at best give you reduced performance, and more likely make things run hotter and puff your pack. Also note that the lower the voltage on the pack when you stop running, the more likely it is to degrade the pack faster, so again having a high capacity pack is better.

Battery Connector:
Any genuine connector type should be ok, provided it is in good condition and properly connected. Genuine Deans, when soldered properly to provide a good connection to its tabs, with the spring clips in good condition, and the tabs not worn down, will do just fine. The same goes for Traxxas connectors and others. If, however, the soldering isn't providing full contact, is a cold solder joint, etc...you're likely to desolder it due to the heat created by resistance, and possibly do damage elsewhere as a result. The same is true for how well the connections are being formed on the connector. To continue with the Deans example, if the spring portion on the back of the tab is weak, or if the tab is worn down, you won't get the full surface area you expect, which will increase resistance and make a bad connection. This also holds true to bullet connections, which many folks are now using and come on many packs today. "Cage" style bullets seem to work (and probably came with the pack to let you charge them), but will only work for a short time before causing problems, because they not only have really thin metal that wears quickly, but they also don't provide more than a few small points of connection on the outside of the cage, and then also have to connect the cage to the core of the bullet. All of those extra, and small, connection points make them both more prone to failure as well as less efficient. If using bullets, use the "split" style where it is a solid post that expands (this is what I run). In all cases with all connectors, make sure you keep them clean. A bit of track dust not only reduces contact and raises resistance, but it also wears the connector out so you're likely to have more problems sooner.

Vehicle:
Why is this here, this is the SCT 410 thread, right? Yep, but this can still vary a lot even on the same vehicle. Make sure your driveline is running freely, that you don't have excessive slop in places, that your outdrives aren't notchy, your wheels aren't rubbing, etc. If any of those aren't true, you're adding resistance to the driveline which will raise the amount of power needed to get the same performance, and therefor stress your system more.

Tuning:
There are many aspects to this, but here's the most basic that will get you into a place you can safely run.
1) Start with the pinion recommendation and the ESC settings above.
2) Adjust pinion up or down based on temperature (using temp gun) and speed on the straight (should hit full speed around 2/3 to 3/4 the way down the straight).
3) Adjust current limit down or up until you no longer see a difference in performance from a stop to that short run up jump, watching temps as you do so if you're raising the limit (or increasing punch).
4) Do more specific tuning around your exact setup. Some motors, like the HobbyWing, actually like timing, so you can play with dropping a tooth on the pinion (or using less KV) for more acceleration and raising timing at end RPMs to keep the speed. Others, like the Pro4, hate extra timing and simply add tons of heat quickly with little to no speed difference. Play with what you have, but always check the temps on your motor AND esc to see how your settings are affecting things.

By following at least these basic guidelines and steps 1-3, you'll always end up with a usable and sustainable electronics setup in your vehicle. I'm sure people with disagree with points in this based on their own individual setups (which are probably exceptions that they came to in more advanced tuning), but you won't get into trouble this way.


Sorry for writing a book, but I thought it was needed based on comments I've been reading over the past few weeks.