Stuttering when driving.

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Which version of raminator do you have? If you have the older one with the red shocks try drilling out your shock piston holes a bit bigger it makes a world of difference on how the shocks work. also make sure the shafts are not bent
when jumping the truck the too small piston holes would cause the shock to not bottom out and bend the shafts
 
Hey guys I’m having a problem. I turn the rear wheels and the transmission knocks and binds. When I turn the fronts it’s smooth and fine. I’ve had this problem before with fronts doing it and it went away. I tried to send a video to primal but U can’t. If anyone has any ideas I can email a video.
 
Hey guys I’m having a problem. I turn the rear wheels and the transmission knocks and binds. When I turn the fronts it’s smooth and fine. I’ve had this problem before with fronts doing it and it went away. I tried to send a video to primal but U can’t. If anyone has any ideas I can email a video.
Are you sure that its the trans or is it the diff?
I had almost the same issue in my front axle for the longest time. Came from nowhere. I replaced several axle shafts, all the bearings and spent days trying to figure it out. I pulled the whole axle, housing and all and spinning straight...no issue. The second you turn the hubs as if your turning...there was severe binding. It would rotate then "pop" past a certain point rotate then bind up again. You could see that she shaft was not rotating on a flat axis and wobbled. What is weird is even new shafts didnt fix it. After paying for a multitude of axle shafts and several bearings from Fast Eddies plus multiple disassembly and reassembly session...the boys at Primal (as they always do) took care of me and replaced my entire axle. Mind you there was very low hours/gallons on my rig at the time. I sent back the entire axle to them in hopes of trouble shooting, as I have been in RC for 30 years and am mechanical inclined yet could not figure out what caused it or why it just popped up for no reason.
@owen_primalrc maybe you can continue to trouble shoot this issue on that axle I sent in and get back to us. Its gotta something simple and its happening more often to folks it seems.
 
I doubt this has anything to do with the issue, but alignment of the drive shaft may be needed. Since the telescoping drive shafts can only be inserted one of two ways, best to have the yokes facing the same orientation, meaning the large pins on the yokes should be on the same side as this will cut down on any vibrations or oscillations in the drive train. Then there is the pinion angle on each axle. Best to adjust the links so the pinion remains in parallel to the driving pins on the transmission. You can remove the drive shaft from the assembly and see if the binding still occurs. If it does, then you can focus more on the axle assembly. If it does not, drive shaft alignment (pinion angle, or something in the transmission.)

As for binding in the axle assembly, it may be due to slop in the pinion shaft. I saw there was a busing mod to keep the pinion in check.

I have yet to tear down an axle so not sure how the differential is secured. If this binding is related to the gear mesh, may need a shim on one side of the differential outdrive ends. If there are any shims in the assembly, confirm they are properly installed based on diagrams. You may have an extra shim or may be missing shims.

Can you rotate the wheels on each axle in counter rotation freely? If not, binding could be in the differential itself. With mine, I noticed the front differential is tight compared to the rear. However, that has changed after a few runs and both rear and front can counter rotate while keeping the drive shaft from rotating.

As for the transmission making binding or knocking noises, it could be related to reverse gear or gear slide not having both pins and springs. I would check the pinion angles on each axle as well as orientation of the drive shaft yokes. I have yet to have issue with drive line except for the missing pin and spring on the gear slide.
 
Good advice...however mine did it with the entire axle out with no driveshaft attached. Was doing it before and after the bearing mod on mine as well. You might be on to something regarding diff shimming, however it is really odd as if you pulled the bearing from the hub, you could see the axle shaft wobble. As soon as you reinstalled it and tried to turn, it would spin free 75% of the way then bind and pop. I never had shimmed the diffs.
 
Hey guys I’m having a problem. I turn the rear wheels and the transmission knocks and binds. When I turn the fronts it’s smooth and fine. I’ve had this problem before with fronts doing it and it went away. I tried to send a video to primal but U can’t. If anyone has any ideas I can email a video.
Advice from everyone else is pretty solid. A very important skill to develop in RC is slowly diagnosing a problem by eliminating one part at a time until you arrive at the issue.

We had a truck recently with this exact same behavior as you describe. The rear axle would bind, and it was only noticeable when rolling the truck forward. Your first assumption may be transmission or diff ring gears, especially when it seems to bind at the same point in the rotation. This was my first assumption too. The issue ended up being very simple thankfully. The rear brake rotor was binding on the drive shaft. It was not floating properly and catching on the brake caliper. I loosened the brake pad bolts slightly to allow for more floating of the rotor, and added some WD40 to the rotor on the connection between the driveshaft and rotor. Make sure to wipe any lubricant off the rotor faces or you wont have any brakes haha!

I would start by taking the drive shafts off and rotating the front axle and rear axles separately. And spinning the transmission over. That should let you narrow it down pretty quickly. If it is a major issue email us and we will help you out. Be patient with responses we are short staffed atm :)
 
I keep forgetting some of you may be running the rear steering setup. I opted to stick with straight axle for the rear.

It was mentioned by the OP and another that when turning the rear wheels this issue comes up. I confused the word turn with rotate in reference to axle rotation and not in reference to change of axis of rotation (rear steering).

Not sure how thick the differential fluid is. The higher viscosity of the fluid for a differential with axle ends that can pivot will result in both wheels wanting to spin at the same speed when making a turn. In reality, the inside will rotate slower than the outside wheel on a turn. If the Diff fluid is too thick this could result in a binding behavior. I had this issue with a different vehicle, Vekta KV5TT for instance. Front differential seemed more like it was a locked diff and was difficult to get the wheels to counter rotate. It was worse when the wheels were pointing left or right and not straight. Not a solid front axle assembly like the Raminator but it did operate similarly. Had to drop the viscosity of the differential oil to that of a shock oil viscosity. That made a huge improvement in performance.

Diff fluid could be the culprit. Lighter weight diff oil may fix the issue of binding when turning wheel direction when also rotating the wheels.
There is also a limit on how far you can turn the wheel before the u-joint starts to bind. The single cardan U-joint does have limits on turning angle. If there was room, a double cardan U-joint would be a huge improvement since they can maintain rotation at a 90° angle vs the short 45° angle (typical limit on single cardan U-joint).

A lighter diff oil for an axle that has steering will improve overall performance. The differential is supposed to allow the wheels to rotate at different speeds when making a turn. Sure, it will spin the wheel with less traction too. Don't go too thin on diff oil if you do decide to make a change.
 
That is weird.

As for the drive shaft, since it is a single cardan type, it is best to have the yoke pins on the same side of the driveshaft (in phase with each other.) If they are out of phase, you will have some issues. At least with the Ram drive shaft, the telescoping part has a square fit so it is easy to keep the drive yokes in phase. The spline types are difficult to get into proper phase like that used on the Kraken Vekta. (I am using that as an example since I have one of them, once I changed the drive shaft from the U-joint to a CV Joint that issue went away. The Raminator driveshaft is easy to keep in phase, you are either in phase or out of phase by 90°. I would have never thought that would ever be an issue until it was brought to my attention in the Kraken forums. Sorry for posting this as most already know all of this stuff. I am just novice.

Here is a link to drive shafts that have use U-joints (yoke and spicers) also referred to as a cardan joint. I am not a Mechanic, so I had to look up the information.

 
I've had it where the screw that holds the drive shaft to the pinion shaft had come loose a bit and it stood a bit proud causing the brake disc to bind.
On my mega truck I had to file the inside of one disc a bit as it would not slide over the drive shaft. Like owen said the discs need to float properly on the driveshaft
glad you got it working
 
Hey got a problem trying to start the raminator up. I tried a new spark plug, reset the high speed needle to factory. It ran great a couple weeks ago but nothing now. Not sure what to try.
I also want to add I have to pull it a bunch of times to get to fire. Not sure if the engines toast or not.
 
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Nope just can’t get the raminator started. I tried starting it 2 weeks ago but it took like 20 pulls. Now I tried it in the garage today with a new spark plug and nothing. I’m thinking about getting another stock motor or the upgraded one for $979
 
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