If you have problems with your input cups around your driveshaft, you may be wondering how you can prevent this happening in future and how to deal with the issue now, right? Let me explain…
How can you prevent your RC input Cup wearing out? How can you prevent your RC input Cup wearing out? The best way to do this is to keep it lubricated. Not just the input cup itself, but also the driveshaft and dog bone joints around it.
Now you know how to prevent this from happening. Ideally, this will be done every two runs, to prevent unnecessary wear and tear. But, let me now explain how you deal with the issue if it’s too late and the damage is done, and more. Keep reading.
What is an input cup?
Before we get into the detail of this article, let me clarify what exactly an input cup is. Basically, an input cup has a number of nicknames that people tend to use interchangeably. You may hear the following:
- Universal joint
- Input Drive Cup
This can sometimes be confusing, especially if you’re a newbie to the RC car game (like me ;). This is just part of the jargon of the game as it can get quite technical. And, it’s something you will get used to with experience.
The u-joint is also used in real cars. It allows the vehicle to push power from the driveshaft while avoiding the friction problems that a conventional dog bone causes. The ironic thing is, this joint still utilizes a dog bone and drive cup on one end.
What is the best lubricant to lubricate your input cups?
one of the best forms of lubrication is WD-40 (Click here to see the price on Amazon), failing that you can use any kind of dry lubrication.
To really make the lubrication spread evenly, move the wheels slowly, while you apply the lubrication. Don’t be tempted to spin them fast, it won’t have the same effect.
The benefits of dry lubricant
The benefits of using a dry lubricant, as opposed to any others, is the fact that it won’t attract dirt and grit which could build up and lead to further issues.
If you are running your car really hard you may even want to lubricate the input cup and driveshaft more than every 2 runs. But this is reserved for people that push their car pretty hard.
What types of lubricants are available?
As I mentioned in a previous section, the dry lubricant is the best way to go. As it will help to prevent dirt & grit to the joints. So, let me give you some more detail on this, as well as sharing another option with you.
Dry lubricant, as discussed earlier, is ideal. It doesn’t actually spray on dry but it dries relatively quickly.
When you use it, make sure that you wipe off the excess spray to avoid any mess. Another advantage of this oil is it doesn’t leave any oily mess behind, like other conventional oils. And, the fact that you can easily wipe it down after spraying on the oil.
Disadvantages of Dry Oil
Like anything, nothing is perfect. There are a couple of disadvantages of dry lubricant that I wish to share with you now.
Firstly, it does not displace water very well. Also, it doesn’t last as long and you may expect. Therefore, you may need to re-apply it more frequently than other options.
PTFE, which is short for polytetrafluoroethylene, is another well-known and respected lubricant used in the RC world (Click here to see the price of PTFE on Amazon).
It can be used for many different things, such as bike chains, RC car parts, and many other applications.
On the surface, it is very similar to silicone. However chemically it is very different.
What if your input Cup has already worn out?
I understand that prevention is only good in hindsight. If you’ve already got a damaged input cup it may be too late.
The reality is, this is just part of day-to-day wear and tear and to an extent, it is expected.
To cut a long story short you need to replace these input cups (Click here to see the price of these input cups on Amazon). It’s something that you should factor into your general maintenance for your vehicle.
However, you should be seeing a good amount of runs with these input cups. If you’re seeing anywhere around 10 runs before they are worn out, then that is a cause for concern.
Are there other driveshaft types to consider?
As you can imagine, there are other driveshaft types to consider. For that reason, I am going to share a few with you now.
The dog bone.
The dog bone is a classic driveshaft. There is a chance, if you have done your research, you have heard of this one before.
It is simply named the “dog bone” for obvious reasons. Why? because it resembles the conventional dog bone.
Advantages & disadvantages of the Dog Bone joint
One of the advantages is the fact that it is quite cost-effective and easy to get hold of.
One of the disadvantages of the dog bone is the increased wear and tear costs due to the friction generated as it’s slotted in the axles drive cups. Also if there is any damage to the camber link there is a chance that the dog bone can be lost because it is not physically fixed in place.
The CV joint
The CV joint is quite similar to the U-joint (Input cup) discussed earlier. One of the benefits and the reason why it’s quite popular is that it’s quite compact in size, It moves very slickly. Also, it is easy to be rebuilt.
Similar to the u-joint, it has a dog bone end as well. The reason for this is to deal with the movement generated from the suspension.
The telescoping drive shaft.
The telescoping driveshaft is quite unique. It will extend and contract in line with the movement generated by the suspension.
The disadvantages of this are the fact that it is a quite complex and expensive option. Hence the reason is not as popular as the dog, for example.
Also, there is room for other problems, such as the axles binding overtime under excess load which will impact the suspension.
What options are there for drivetrains?
Now that we understand the options for Driveshafts. Let me explain the options with drivetrains.
What is a Drivetrain?
Before we delve deep into the options. Let me first explain what a Drivetrain actually is.
A drivetrain, according to Wikipedia, is the module which drives the power to the wheels. It effectively transfers the power from the motor to the wheel, with the assistance of the driveshaft. Here are a few different variations:
The direct-drive drivetrain has a Spur Gear that is mounted directly onto the drive. Hence the reason it’s called a direct drive. The pinion gear, which is the gear that makes the motor move, is linked directly with it.
This direct drive is exclusively available to pan cars. One of the big disadvantages of this is the fact that they are susceptible to damage to the gears. Why? because they’re wide open.
Simple things like debris or dirt can get onto it without any effort, which will clog up the system. If this happens, it could rend your car unusable, which needs to be avoided at all costs.
However, one could argue that it’s not a big issue because these types of vehicles are not really off-road vehicles really. They are typically used on smooth, prepared surfaces. So, the chances of them getting into these issues is minimum. So, maybe it is really not an issue for you at all.