Dogbone on Drivetrain Rubbing Chassis Brace

[parcou]

I do not know if this is an issue or not....

I added the HR front chassis brace and titanium dogbone drive trains which is much thicker dogbone than the original. I noticed on my first run today after installing those items it appears to be rubbing. When free-standing and turning the drivetrain by hand I see nor hear any rubbing but that's not under power. When under power on the workbench I do not see any rubbing but the RC is static on the bench. The damn car is so powerful for the rookie/newbie here is does not seem like an issue. But I need your thought or advice if I need to do something to modify/fix/etc.

Any thoughts?

 

[suchtragedy]

You have the infraction or limitless, right? I think that's what it is from the pictures. I know that the reason those thicker dog bones exist is because at high speeds the factory dog bones oscillate and snap, mainly in the rear drive shaft because it's really long for how thin they are. Maybe when the car is in motion there's just enough drive shaft play in the cups that it is oscillating just enough to rub. That clearance it shows in the pictures looks very, very small, like 2mm at most.

If the rear dogbone isn't an issue and it's just the front I might consider going back to the stock front dogbone. You could also check to make sure that you don't have any shaft play in your diff/spool at the mount, and that your diff cups aren't mounted slightly crooked or something, or that you don't have a slight twist in your chassis... honestly it's hard to say because any small thing that's off could cause it to rub because the clearance is so small.

 

[parcou]

You have the infraction or limitless, right? I think that's what it is from the pictures. I know that the reason those thicker dog bones exist is because at high speeds the factory dog bones oscillate and snap, mainly in the rear drive shaft because it's really long for how thin they are. Maybe when the car is in motion there's just enough drive shaft play in the cups that it is oscillating just enough to rub. That clearance it shows in the pictures looks very, very small, like 2mm at most.

If the rear dogbone isn't an issue and it's just the front I might consider going back to the stock front dogbone. You could also check to make sure that you don't have any shaft play in your diff/spool at the mount, and that your diff cups aren't mounted slightly crooked or something, or that you don't have a slight twist in your chassis... honestly it's hard to say because any small thing that's off could cause it to rub because the clearance is so small.

Good info and I will look. I do have the Infraction...

I believe I understand all you noted but what do you mean by... "shaft play in your diff/spool at the mount"

 

[suchtragedy]

Good info and I will look. I do have the Infraction...

I believe I understand all you noted but what do you mean by... "shaft play in your diff/spool at the mount"

Like any wobble, even small from bearings or if you have the stock motor mount the plastic top piece having some wear so the bearings aren't perfectly secure, or the diff cups not being 100% straight and slightly crooked causing an uneven spin, etc.

When it's on the bench with wheels off the ground, did you go full throttle and watch it or just a small amount of throttle? Try full throttle if you haven't.

Here's a video of oscillation in case you aren't sure what I mean. This is what you want to look for to see if this is what's happening or not.

 

[parcou]

@suchtragedy can you take a look at the videos I posted. I connected the battery and lifted the Infraction up to test.

The phone was hard to hold without it wobbling and having to pull the remote trigger...sorry for the extra motion. I am new at this but I do not see moving at the front and center outer gears but it was also hard to keep the focus as it began to move. In addition in this game, I am sure small is a lot. I also am not seeing any grinding meaning any metal shavings dropping. The DB do a lot of front to back movement but I am sure that is normal since it does have a lot of room to move back/forth:

• video1
• video2
• video3 extra shots
• video4 extra shots

Thoughts?

 

[Mr.Duke]

Use a small sanding roll to clearance around the point of contact on the chassis brace

 

[parcou]

Use a small sanding roll to clearance around the point of contact on the chassis brace
View attachment 85911

Thank you....!!

 

[SrC]

Yep a Dremel is your friend for sure. Any driveshaft MUST Never hit/touch anything when its spinning. Chassis flex/twist under running load occurs and must also be taken into consideration for center driveshaft clearance.