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This page is devoted to steering issues. Have you noticed that your MGT turns more to one side than the other? Is your linkage loose (or stiff)? Wanna put ball-bearings in the bell cranks? Have you seen the ball-ends hitting the front diff? Would you like to decrease the turning radius? Curious about which tires give you best turning radius? Well, these questions and more will be examined on this page. Also on this page are the modding tricks to get maximum rotation from the front end. If you are using all the stock parts and tires, and DON'T want to do any serious mods, then a good way to make sure you have maximum turning available is simply to do the "Steering Tune-Up", located below. Of course, you should do this after you do mods too. NOTE: this page will not get into definitions of "toe" or "caster" or "camber" or "Ackerman". However, you should know what these terms mean or much of this page will be useless to you. Click here for a nice, easy page that explains these terms. OK, assuming you now know what all the terms mean, let's get started. Your first question probably is: how does this guy think he knows what the different measurements actually are? The answer is: I built my own set-up board so I can accurately (in degrees) measure toe, camber and Ackerman. Caster is not adjustable on the MGT, so I have not attempted to measure it. Caster is set from the factory at a few degrees positive. TESTING PROTOCOL - Unless otherwise noted, I am using zero degrees toe and zero degrees camber for all tests. Also, I will typically give maximum wheel rotation measurements as 30°/22°. What this means is the wheel rotates 30° in one direction and 22° in the other direction. The difference in wheel rotation is due to the Ackerman effect. So, if I said a particular test showed the left wheel rotating 30°/22°, that would mean that in a left turn the wheel rotation is 30° and in a right turn the wheel rotation is 22°. The inside tire will always turn more, that is the Ackerman effect. Also, in this example we would have a TOTAL rotational ability of 52° (30 + 22). Here's a pic of my set-up board in action: OK, let's address one of the very first basic issues that a lot of guys notice. That is, your MGT turns better one way than the other. The cause is usually that your turnbuckles are not equal length. Thus, one of the ball-ends is hitting the diff and limiting the rotation for that side. So, the first step is to take them off and adjust them so they are equal length, as shown below:
After you have them set the same, always remember to adjust both equally, to keep them equal length. You need to carefully adjust the alignment and centering of the parts, but that is explained in more detail towards the end of this page. I had been racing my MGT all summer of 2004 and thought I was pretty close on the steering adjustment. The I put it on the board and got readings that amazed me. I mounted and squared everything, then started turning the wheels right and left, while taking degree readings from the protractors. This was a very interesting experiment. Here's a pic of a typical reading:
Left wheel - 20°/20°
(total of 40°) I started by removing the turnbuckles and equalizing them. Then, when I re-installed them I left off the small washers to let the ball-ends get as close as possible to the diff (and it's close, lemme tell ya!). Now, my new measurements were as follows: Left wheel - 33°/19°
(total of 52°) So, you can see I picked up a ton of steering already, just by equalizing the turnbuckles and by fixing a problem that I had created myself (using the small washers). So far, the testing had been done without any wheels mounted. You might not know, but on the MGT there is a problem of the rim hitting the turnbuckle on the inside tire at full turn. So, I mounted four different tires to test this out. For each test, I mounted a different tire on the right side, and then measured the left on the degree wheel. Here are the results:
You can see that the 40 series BowTies rims allow for good rotation, but they still contact the turnbuckles. The stock MGT rims and T-Maxx style rims both hit the turnbuckle even worse and cause you to lose some turning rotation. However, the wide offset T-Maxx rim does not even come close to hitting the turnbuckle.
I wanted to see if there was more turning available (and I wanted to keep using the small washers), so now I had to fix the ball-end washers hitting the diff. I did this by making a new steering arm. Here's a pic of my modded steering arm. This arm is only temporary and I whipped it up in about 10 minutes, so I know it looks like a piece of crap, but I am just trying to check different alignments right now, so bear with me. The FT arm is sitting right above my modded one for reference. You can see I moved the outer holes about 1/8" further out. This moves the ball-ends away from the diff and will allow clearance for the small washers. Then I simply shortened the turnbuckles to get back to zero toe, which is what I am using for these tests. My modded arm needed more grinding on the bench-grinder to get it to fit perfectly. After a little more grinding I got it to fit perfectly. So, now I tested the rotation with my modded arm (no tires mounted) and got the following: Left wheel - 33°/19°
(total of 52°) So, I've pretty much ended up at the same point as the stock steering arm. Now I repeated my tests as above, this time using my modded steering arm, where I mounted a tire on the right side and measured the left, to test the turnbuckle hitting the rim. Results as follows:
These results are really about the exact same as those above, so my modded steering arm did not change anything, except it will allow me to add the small washers on top of the ball-ends (to prevent them from popping off). The stock steering linkage will give you about 52° of turning, but it just needs to be meticulously adjusted. This section describes the mods necessary to reduce
turning radius. There are really three things you need to do: You can make a modded drag link out of aluminum stock (about 3/16" thick) and then drill/tap holes, or you can simply use a flat piece of steel about .060" thick. If you use a flat piece of steel, then you need to use nuts on the end of the mounting screws. Next, you need to grind some relief into the front
knuckles. DON'T GRIND TOO MUCH! You only need to do it on one side of each knuckle, as shown in the
pic below. After you grind the knuckles, if you do the "steering tune-up"
located below, you will have vastly improved steering. Of course, now you will
need a good steering servo!! Don't forget about the a-arms, they will need a
little Dremeling also (see pic). Your key indicator of how successful you are with this mod, is that the turnbuckles should now be solidly hitting the a-arms on both sides. It's quite possible that you may need a new longer servo saver or servo arm, to increase the throw as you will now have more rotation. This is why a good servo is so important. Steering Tune-Up Before you start this "Tune-Up", make sure all your parts are good. Fix loose ball-ends, replace or repair weak servo savers, then go ahead with these steps to tune-up and adjust your steering system: 1) Disconnect the servo arm or servo saver (make
sure servo saver is strong)
Here's another trick to help with steering. This will smooth out the stock steering bellcranks, use bearings and replace the plastic bushings. The bearings are standard clutch bell bearings (5 x 10 x 4 thick). Here's a link to washers that you can use on top of each bearing: small washers. Here's a pic showing how things go together: Don't forget to upgrade your servo saver to a really good one. I like the heavy-duty from Duratrax. It's really cheap but does a great job. Duratrax servo saver at Tower Hobby. Alternatively, you can use the Factory Team kit. Factory Team Steering Kit If you are using the stock radio gear, the first thing to do is the famous "Channel 4 mod". From Canadian-MGT at the Monster GT forum: here's a pic showing what you need to do, take the battery plug out of the battery slot "A" in the photo and plug it into the channel 4 slot "B".
If you're still unhappy after you do the Channel 4 mod, you should start thinking about upgrading to a better steering servo. There are lots of good ones, but one of the best (and my favorite) is the 94358 Airtronics, with 200oz of torque and 60 degrees of rotation in .10 seconds. Besides the steering servo, another good upgrade right away is a rechargeable NiMH battery pack. Get one with at least 1100 MaH. If you want super-strong steering with quicker response, then take a look at the 2-servo steering mod page. For the ultimate in steering, consider the 4-wheel steering mod. BEST TIRES FOR TURNING Curious about which tires provide best turning? So was I, so I checked out four sets of tires to see what the effects on turning radius would be. I tested the stock MGT tires, ProLine 40 series BowTies, standard T-Maxx tires, and wide offset T-Maxx tires. Before I started these tests, I made sure to align my front end using the "Steering Tune-Up" steps above. Once I did that, all I did was to change tires and measure the turning radius. I wanted to be sure I was repeating the tests as accurately as possible, so I tried to minimize all the variables. I repeated each separate radius test about six times and then I switched the tires to the next set. I mounted each set of tires twice, so I actually did about a dozen radius tests on each set of tires. I put a piece of duct tape across my carpeted floor and made marks on it, both starting and finishing marks. I used the marks to line the truck up the same way for each test. I turned the wheels (using the radio) to maximum left turn for each test, I turned the wheels before moving the truck. I used small pointers on each end of the truck and lined them above the marks, as shown in these two pics:
After I had everything lined up and the wheels held hard left, I gently pushed the truck until it came around and the front pointer hit the center of the tape. When using the same tire my measurements were actually all quite similar, thus validating my test protocol. I would then take a measurement, as shown below:
The different tires had quite an effect on turning radius. Here are the results:
So, if you want the tightest turning radius, then the wide offset T-Maxx tires are the clear winner from these four. There is quite a noticeable difference in the turning radius as I was doing the testing. Hope you find this information as interesting as I did. Don't forget about weights of tires. Heavy tires will slow you down. Good luck!! |
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