Jump to content
Klausen

Monster Beetle re-release #58618

Recommended Posts

Looks like a lot of wheel wobble, are the wheels out of balance? I run alloys so I can't say for sure... They run very smooth, actually when I roll it, by the time I walk across the field to turn it back over the wheels are usually still spinning freely... (Fronts)

Share this post


Link to post
Share on other sites

Looks like the wheels are out-of-whack??? I'm sure you've checked, but are the rear wheels mated to the 5-point rear hubs correctly??? Is the hub seated on the pin correctly???

Terry

Share this post


Link to post
Share on other sites

Yeah I thought the same so I swapped the wheels and hubs with my vintage MB and the problem still exists :(

Share this post


Link to post
Share on other sites

Is there any play in the U-joints? Anyone tried swapping in re-re Frog dogbones or vintage half-shafts into the same re-re MB gearbox to see if the behavior changes?

Have you tried it with the rear dampers detached, or with vintage dampers, to rule out some sort of elasto-harmonic oscillation inadvertently attuned with the new CVAs?

Share this post


Link to post
Share on other sites

How well do the axle bearings fit in the suspension arms? I've had similar issues with loose-fitting bearings in WR02 rear knuckles. Also are the bearings fairly snug on the wheel axles, or can they wobble?

Share this post


Link to post
Share on other sites

have you checked to see if the motor shaft is bent?

Or,

is the hole in the pinion gear central?

Share this post


Link to post
Share on other sites

Is there any play in the U-joints? Anyone tried swapping in re-re Frog dogbones or vintage half-shafts into the same re-re MB gearbox to see if the behavior changes?

Have you tried it with the rear dampers detached, or with vintage dampers, to rule out some sort of elasto-harmonic oscillation inadvertently attuned with the new CVAs?

Hold on, I'm still tryin to translate this last question....

BEEF!

I didn't know you were that proper and well edjamukated....

Very impressive!!!!

Share this post


Link to post
Share on other sites

All the above are very welcome ideas on a mind boggling problem but I've over the week's I've had the MB have checked every one of those ideas from bent shafts rubbing drive shafts dodgy bearings broken teeth on the gears etc etc etc and its all perfect! I go to use it and it vibrates like its having a seizure! "Baffling"

Share this post


Link to post
Share on other sites

Loads of good points here, thanks fellas, I'll be trying them all.

I'm going to build my sons kit next and see if that suffers the same fate. I'm going to keep his 100% stock, even down to plastic bearings and see if his is ok. I hope it is, I really don't want Santa delivering a duffer Crimbo prezzie.

Share this post


Link to post
Share on other sites

OK, let me see if I have the facts straight....

Full downward position of suspension, part throttle = shakes.

Slight compression of suspension = shake goes away.

Full throttle = shake smoothes out.

My best guess is that the dogbone ends of the driveshafts are binding in the drive cups, due to the angle being too steep. When you compress the suspension, the angle gets shallower, so the shafts can run freely. And at full throttle, they sort of "float" in place, instead of falling into the sides of the drive cup. It actually sounds quite a bit like my old Falcon did, before I put limiters inside the shocks.

Couple of possible solutions:

1. Find the exact point at which they free up in the suspension travel, and put limiters inside the shocks exactly that length to prevent them from drooping down into the "wobble zone."

2. Mill/drill out the inside bevel shape of the drive cups to a steeper angle, to allow the shafts to operate at a steeper angle. (This one might be trickier.)

  • Like 1

Share this post


Link to post
Share on other sites

+ an easy one to check , C11 Wheel hubs ? are they good & look straight , pin sitting in it nicely . could be some thing

simple , even the rear arms not straight ... Can you try hornet/frog wheels & see if it does the same ?.

Good luck , or sell it as a wacky monster beetle ( like a clown car ) on evilbay :lol: ..

Share this post


Link to post
Share on other sites

OK, let me see if I have the facts straight....

Full downward position of suspension, part throttle = shakes.

Slight compression of suspension = shake goes away.

Full throttle = shake smoothes out.

My best guess is that the dogbone ends of the driveshafts are binding in the drive cups, due to the angle being too steep. When you compress the suspension, the angle gets shallower, so the shafts can run freely. And at full throttle, they sort of "float" in place, instead of falling into the sides of the drive cup. It actually sounds quite a bit like my old Falcon did, before I put limiters inside the shocks.

Couple of possible solutions:

1. Find the exact point at which they free up in the suspension travel, and put limiters inside the shocks exactly that length to prevent them from drooping down into the "wobble zone."

2. Mill/drill out the inside bevel shape of the drive cups to a steeper angle, to allow the shafts to operate at a steeper angle. (This one might be trickier.)

That's what i have said above , a few post ago . dog bone & outdrive problem

Share this post


Link to post
Share on other sites

posted this on youtube:

Simple the wheels are way out of balance , a lot of my tamiyas do this lunch boxes and wild willy types you balance the wheels and they run smooth... if it's only doing it with the wheels on there out of balance.

Share this post


Link to post
Share on other sites

posted this on youtube:Simple the wheels are way out of balance , a lot of my tamiyas do this lunch boxes and wild willy types you balance the wheels and they run smooth... if it's only doing it with the wheels on there out of balance.

Sadly not, I tried a set of vintage wheels on and still had the same issue :( I can rule the wheels out.

Share this post


Link to post
Share on other sites

posted this on youtube:Simple the wheels are way out of balance , a lot of my tamiyas do this lunch boxes and wild willy types you balance the wheels and they run smooth... if it's only doing it with the wheels on there out of balance.

Sadly not, I tried a set of vintage wheels on and still had the same issue :( I can rule the wheels out.

+ an easy one to check , C11 Wheel hubs ? are they good & look straight , pin sitting in it nicely . could be some thing

simple , even the rear arms not straight ... Can you try hornet/frog wheels & see if it does the same ?.

Good luck , or sell it as a wacky monster beetle ( like a clown car ) on evilbay :lol: ..

I'm going to start the build of my sons tonight and if that goes well then I might just paint this one up nicely and have it as a shelfer. I've always got my vintage basher to take out...which also translates to 'I'll wait 6 months until someone brighter than me finds the solution on here and then apply that idea' ;)

Share this post


Link to post
Share on other sites

Has this problem never been reported before in vintage Monster Beetles?

Also, what about the re-release Frog and Brat? Do they suffer from it?

Share this post


Link to post
Share on other sites

Yep tried different motors different pinion gears frog/brat rear arms different wheels tyres I've put frog rims & tyres on! Aaannndd still does it! I've narrowed it down to diff or drive shafts but they are all smooth no rubbing (no sign's of rubbing) so as yet unknown!,I could change it all for the vintage drive gear but that would be admitting defeat!! And I'm going to find what it is!!!!!

Share this post


Link to post
Share on other sites

Anyone try this?

First there should be some play in the axles if you pull one in and out there should be a little play also the end of the dog bone running into the diff out drive cups there should be a little play sometimes when the suspension is fully down position when off the ground the dog bone Or CVD ends can bind while rotating the wheels, rotate the wheels slowly both at the same time when up off the ground and feel if the rotation gets easy then hard, if it does check if the dog bones are jamming to hard into the diff cups or the bones pin is pushing into the drive cups on one side during rotation, this will make that out of round running motion.

Also to check if it's the CVD'S a simple test hold up the car and compress both rear suspension arms so the CVDs lay flat across on both sides , do this test with the car running at the speed it makes the vibration and if when you push both sides up CVDs shafts level and the vibration stops it will then tell you it's the CVDS they are being angled to far or there is not enough space in-between the parts and they are jamming causing the lobing out of round motion.

Somebody please do this test and see if it gets smoother when drive shafts are flat level across when the car is running.

hope this helps.

Share this post


Link to post
Share on other sites

My new plan is to pull my new built Brat out of he loft, strip off the driveshafts and fit them to this. If it works, I'll know for sure what it is, either way. If it works it was the shafts, if it's still borked, it's the gearbox.

  • Like 1

Share this post


Link to post
Share on other sites

My new plan is to pull my new built Brat out of he loft, strip off the driveshafts and fit them to this. If it works, I'll know for sure what it is, either way. If it works it was the shafts, if it's still borked, it's the gearbox.

I'm sure it's the drive shafts , looking at the out drives , that seem longer than the norm + the cvd's .

Would not surprise me there is the problem . Hope you get a good result & confirm the problem .

As this is the only thing that has changed from the vintage too the re re rear end ..

Share this post


Link to post
Share on other sites

I'm thinking its something to do with the shaft's but no idea what? Because I've had a torch in there driving it slow and no binding or touching of anything and at speed there is no marks of any description at all the one and only conclusion I've come to is the drive shafts can't cope with the size and off balance that the bigger tyres & wheels produce bit then I did put frog tyre & rims on and it did the same??????

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

×
×
  • Create New...