Mad Monkey diff

[lordnikon]

It was pointed out to me that my diff was way to tight, no counter rotation when spinning the wheels by hand and very notchy.

I'm rebuilding it with new balls, plates, thrust bearings etc and it now feels super smooth and rotates as expected. Broken it in but sounds like a hoover when running.

Do these cars just have noisy diffs ?? It has the Kevlar 52T and kevlar idlers too if this makes any difference ??

[lordnikon]

Should add it has some rc lazy ceramic diff balls in it, but a standard kit thrust bearing

[racingdwarf]

sonds like it maybe slipping a little, run it a little tighter, if you are running on a high grip surface with the slipper tight, you may need to run the diff tighter, and back the slipper of a little.

[bazdonsop]

there is a video series on you tube done by racer53 on this subject and i found it extreamly usefull as i have burnt out my diff and destroyed the idlers after two months of light use,
I have gone for ceramic answer diff bearings and ceramic bearings on iders, kevlar diff 52t, acetal idlers and team acc diff grease.
after £40 on a diff and the monkey kit only £65 well you know where i am going with this but its worth it not having to keep doing it.
my diff too is a little noisey but feels really smooth
Hope this helps

p.s when setting up the slipper like shown in the video, make sure the slipper isnt too tight, lets just say i took it on the chin

[lordnikon]

Its on a high grip astro with the slipper backed off, think i will try tightening it alittle and see how it goes. Could just be its noisey, drowns out the fan

[gordy]

I've been using the stock diff and had no issues at all. I think the key is to use a really good grease on the thrust race not ball diff grease it just doesn't work on the thrust race mines quiet

[lordnikon]

Well after 3 hours of testing last night its still noisey lol

If i tighten the diff anymore it will lock up and stock counter rotating, the slipper is backed off and its still making a racket. Wondering if i have maybe put the thrust race in wrong or something, really cant be bothered pulling it all apart again........ rapidly losing my patience with it too - DEX210 here i come

[VintageRacer]

Is it noisy all of the time or just at launch? My sons makes a squeal as he starts which I assume is the slipper, but it is quiet once it's going.

I don't think I've done anything special. The diff is tightened until I just can't turn one wheel whilst holding the other and the spur.

He is running a tame motor (17.5) which might be helping.

[lordnikon]

Its pretty noisey all the time, makes the launching squeel and then does go quieter. I've got a turned down 5.5T on mine, so its equivilant to running a 7.5T i would have thought.

[Tom3012]

A squarking diff on launch usually means its too loose... Did you replace the diff spring when you rebuilt it? If the springs old and tired tbis really wont help you set the diff... Something to try!

[lordnikon]

Yep new spring, screw & nut, thrust bearing, diff plates, diff balls, all cleaned and degreased before being rebuilt with new stuff. Kevlar gear was fine so this stayed

[Robbiejuk]

Originally Posted by lordnikon

Yep new spring, screw & nut, thrust bearing, diff plates, diff balls, all cleaned and degreased before being rebuilt with new stuff. Kevlar gear was fine so this stayed

How about making us a video of the noise? Might help us ascertain what it is and what it isn't.

I haven't used the kevlar diff gear yet, but I do have the nylon idlers, I personally think thats all you need to replace in the gearbox as I have never had a problem with the diff gear itself.

If your car is making a chriping noise on take off it is definatley a slipping diff. Did you compress the diff spring with a pair of pliers a few times before you put it in?

[lordnikon]

I just grabbed the diff gear when ordering the nylon idlers, wanted to build something as strong as possible.

I stripped it all last night again, replaced the thrust bearing and packed with plenty of grease, touch wood it now seems ok. Not sure what i did originally but maybe damaged the thrust bearing when bedding in ??

[Robbiejuk]

I reckon it was the spring, it has probably bedded itself in now and so when you put it back together again you were able to tighten the diff properly rather than it feeling tight but it was not actually tight enough.

Good to see you have sorted it

[Black Sheep]

I've just finished putting my mad monkey together, I've taken it apart and done different things with the dif, tightening it as much as I can each time.

at the moment I'm certain the dif is slipping so I cleared the grease out of it (used a thin lithium grease) and put a thin smear of the grease provided in the kit.

when I try and roll the car along it's stiff and doesn't roll easily, the pinion on the motor isn't turned (brand new motor)

I don't think I can back the clutch off much more before the nut will come off.

at the moment, when the car is off the ground the left rear wheel spins under light power, but not the right,

sorry it's not much to go on, I'm used to things like Tamiya TL01's, ball diffs and slipper clutches are new to me!


is it better to have a thin amount of grease or a good amount of stiff grease?

[SamRCRacing]

If the diff is tight then losen it off about 1/4 of a turn, and there is a little washer that if you leave out it puts allot of resistance and spur wont turn. It's green and very small, I had the same probem yesturday.

HTH

[Black Sheep]

I remember putting the little green washer in, I'll try slackening the diff off a little,
will that not allow the diff to slip still?

[SamRCRacing]

losen the slipper to counteract it, that should do it.

[Black Sheep]

The slipper is as loose as I dare go, the bolt is flush with the end of the nut poking through.


going to strip the diff again tomorrow and leave it snug but not tight and see how that goes.

at least I'm getting good practice for doing running repairs.

[nmpsilva]

I had the same problem.
My gears were always striping and if i losen the slipper anymore the nut would fall.
I solve the problem with the dremel.
I sanded a little bit of the spring on each side and it gave me the control off the slipper.
Now the slipper slippes and the nut wont come off.

Cheers