A little help fella's.. my medusa is sounding really odd all of a sudden, bearing? - RC-Monster Forums

stum

Please listed and tell me what you think of this noise... it just seems off from when I installed the beasty.. bad bearing maybe? Thoughts?

Never over temp that I know of... in fact VERY low temps typically. The other day I snapped my tekno elektri-clutch and it was just wobbling on the end... so who knows what that may have done for those seconds before I realized something was not right.

Anyway #1 nothing wrong and it's in my head #2 bad bearing #3 worse

Thanks!

BL_RV0 · 04.26.2009, 10:20 PM

Sounds like a bad bearing(s) to me.

Metallover · 04.27.2009, 04:43 PM

I just got a used medusa and it sounds something like this... What did the problem turn out to be?

stum · 04.27.2009, 05:14 PM

I talked to medusa on the phone.. they said send it in as it sounds like a bearing. Who knows though... if I get it back and nothing was done I'll know it was in my head. It sounds like a bad bearing to me too though.

Unsullied_Spy · 04.27.2009, 05:22 PM

At least the front bearing is shot. E-Mail them and they should replace it for you.

BrianG · 04.27.2009, 06:02 PM

Definitely a bearing. I had a 4600 that sounded something like that and it turned out to be the front bearing. Makes sense as there can be quite a bit of lateral pressure depending on how the mesh is set and how much chassis flex you have.

Metallover · 04.28.2009, 08:06 AM

Is it possible to repair the bearing yourself?

04.28.2009, 09:31 AM

Definitely a mashed bearing

i suppose if you pop the end off the motor by hitting the motor shaft you could get into it and change the bearings yourself.

I think brian hit on the problem really these motors are designed for use in aeroplanes and thus the bearings are not super durable.

Add to this that most nitro conversions have motor mounts that allow too much change in the mesh between the pinon and spur when under driving loads. Mikes mounts seem to be the best for avoiding this as the mount is directly integrated into the spur/differential mount thus having a direct and fixed connection maintaining a more consistent gear mesh.

Once you have replaced the bearing i would do some or all of the following.

1. Get a new motor mount that solidifies your gear mesh better.
2. Dump the clutch it just adds unnecessary not particularly well balanced weight to the motor shaft and get a pinion.
3. Set quite a loose gear mesh and check the mesh throughout the entire rotation of the spur gear (they don't always spin concentrically)

stum · 10:15 AM

The chassis I use in my 8ight is the Tekno v3 nobody makes a more secure motor mount, nobody. It's in a solid unit that mounts directly to the chassis, there is no 'wiggle' room and always has perfect mesh. This is why I chose the v3 chassis, It also allows for mechanical brakes and the clutch. Tekno just released a new clutch that I may switch to if I don't just go w/ the pinions instead, we'll see. It's a 1 piece w/ 3 shoes vs the old multi piece w/ 2 shoe design.

Thanks for all the help though guys.... much appreciated.

PS I don't have a pic of the buggy loaded but here is a pic of my tekno-v3 8ight-t chassis which has the same mount (though I have a plate over it with the MMM v3 on top of it). I have since switched this one over to a pinion as the clutch just got way too hot.... pads would be smoking efter running a pack.

lincpimp · 04.28.2009, 10:17 AM

The chassis can still flex and change the mesh. Plus the added weight of the clutch will wear the bearings out faster, no way around that. They should incorporate a front bearing block to support the end of the clutch assy. Sure it would add some weight, but if you are hell bent on having a clutch you are not all that worried about weight...

Metallover · 04.28.2009, 08:30 PM

Are there better bearings that can be put in a medusa? Something better then the OEM?

BrianG · 04.28.2009, 09:19 PM

Quote:

Originally Posted by lincpimp

The chassis can still flex and change the mesh...

+1. Having the pinion and spur on the same mounting plane makes chassis flex irrelevant. Any other mounting scheme has the possibility of slightly adjusted mesh when the chassis flexes (and it does). The best way I've found to eliminate forward/backward flex is to make a top plate that attached from the rear diff, center diff, and front diff.