45mph pede

Well as I was lubing everything up to go 75mph, I took of the motor mount and the metal pece above it, and this is what I found. I have no idea how this happend. Got any idea's? I also found that my cvd had some scrapings, but that I found is from the steering (wheen it turns all the way left the screw holding part of it scrapes it) Im kind of mad about that, but its cool, Im very worried about this misterous scraping that I cant figure what happend or how it happend. Maby it comes this way?! Thanks,
-Wes

Picture:

aliens8mycow

That's a good one...

Are you talking about the 'ring' where the spur meets the motor plate? That's what's there, right (again, I'm not too familiar with the pro4)? Is that ring where the screws that hold the spur would run around when the wheels are turning? I think I'd look at it assembled, and see if it's machined that way to provide clearance for the spur screws, or if the diff case is flexing, allowing the spur to flex, and therefore rub the motor plate.

That might also explain the wear on the shaft (is that about where the end of the 'outdrive' meets the shaft when it's inserted?)

45mph pede

Thats right were the spur is yes, but its a good distance from the metal plate that is grinded... Its very strange and scary.
-Wes

45mph pede

Some more pictures to help.

aliens8mycow

So the spur screws have plenty of clearance (even without the ring there)? Did the shaft always have the ring, or is that new too?

Maybe your car is trying to give itself a makeover and get rid of the purple anodizing...

If the diff housing are flexing around that much, that the spur is reaming out the motor plate and the outrive spool is cutting up the shaft, that may explain why you're chewing up bevel gears in there.

You might be in need of some cf or aluminum on there! [X(]

aliens8mycow

The shaft doesn't sit far enough into the spool to be grinding on it from what I see in the pics (actually, I don't see the wear ring in the second pics)

45mph pede

Thats frustrating... Why would they design somthing like this that they know is going to grind[]
-Wes

aliens8mycow

...you're sure it's not that way from the factory?

Which end has the grind on the shaft? I didn't see it in the second pics - is it at the front?

45mph pede

The marks are in the back, by the spur. The pictures I took are of the front and side. I cant get any pictures that would answer if it came like that factory. The only pictures I can get is from tower and they are of the front
-Wes

aliens8mycow

I'm with you on the motor plate.

I'm talking about the shaft - is it worn at the front or rear? In the pic of the rear of the car all assembled, I didn't see the ring on the shaft where it was worn. It also looked like the ring would be further down the shaft than the spool could reach. Is there something else that it could rub against?

aliens8mycow

If the shaft is worn up front, is it hitting the servo linkage or something? You mentioned the CVD rubbing...

45mph pede

Ohhhhhhh

Its worn at the front where the steering is. Im pretty sure it rubs on the steering thing is. My pictures exsplane it better than me. This makes me think that somthing big time moved casuing alot of other things to move around... [&:]

aliens8mycow

Allright... well that makes more sense. Do you wear that purple feather hat while you drive this?????

If you take a little steering travel out from the tx, does that solve it? Or would you have to trim it down too far? That shaft is gonna be 2 half shafts before long! [X(]

Do you think it's the diff case flexing in the rear? If the front flexes enough to snap the bevels, I'd think the back one would flex too.
I mean... the whole suspension is mounted to the diff case! Any cornering forces, or motor torque would probably twist that thing all over the place.

Hmmm... do they make those in aluminum? (purple of course)

frailcow

Tip for close up photos: Use your camera's macro mode (often indicated by a flower).

aliens8mycow

Are your bulkheads plastic, graphite, or carbon fiber? I couldn't tell for sure from the pics if they're plastic or graphite.

I found some graphite ones on HPI's website for $12 and $18, and some (purple) aluminum lowers for $40 each.

I wonder if these would eliminate some of the flex? Do you really think that flex is the issue? You also mentioned a cf brace earlier that fits around the bulkheads and has some extra camber settings - I wonder if that would do the trick?

Here's some pics - see what ya think.

Galifrey

Sheesh is it just me or is it scary how similar that car is to the TB Evo IV...

45mph pede

Well... It looks like im going to get all that, so it stops flexing. Does anyone eles have this problem though?

Sorry about the picture I was in kind of a hurry to get it, and it was like 11o' clock
-Wes

aliens8mycow

Do you really think that's what it is? I hate to see you spend $100 on a guess...

R40Victim

I'm building my Pro 4 right now. I can't see how it's flex that's the issue. As I'm assembling mine, I'm pulling, twisting and tugging to see how rigid this thing is. It's gotta be as, or real close to as rigid as both my nitro cars. If it's flexing, you've gotta have loose or stipped screws. It looks to me like one of the screws backed out, and chewed the motor mount. I think you guys nailed it with the steering. Looks like the turnbuckle was rubing on the shaft. Do you run it at a track with alot of right hand turns?

I use thread lock Everywhere. After having a few loose screws end my raceday, I'll never let that happen again. I know the instructions say to use oil when installing screws into carbon pieces, but there's a few places where it just isn't needed.

aliens8mycow

I have to agree with you about the flex - it seems unlikely, but a 75mph the forces on the car are probably a little more than we could apply with thumb and forefinger. Still seems far-fetched, aside from the fact that the pro4 diffs like to eat bevel gears (as we've recently figured out). That again leads me to believe that something is getting tweaked in there.

Let's make the mystery even deeper -- the bevel gear issue is up front, where you only have cornering forces at work. The rear diff isn't chewing up gears, but apparently still moving around somehow...

I don't claim to be an expert, and I'm not sure that we're even chasing the right lead. Just trying to brainstorm and put as many ideas on the table as possible, so 'pede can sort through them as he sees fit.

I know that aluminum and cf make nice bling-bling, but it seems weird that a car that came out of the box with tons of aluminum and cf has ended up with so many aftermarket parts related to the bulkheads and diff housings. Is it really just eye candy, or is it a useful upgrade?

bcmorris

I took a close look at my Pro4 and had three thoughts.

1) Did you tighten your servo saver all the way down? I mean, if it's tightened really, really far then the steering linkage will be lower and might rub.

2) Are you using the correct ball stud for the steering? If you're using a longer one it will stick out the bottom and might be rubbing on the shaft.

3) Double check that the correct bearings are installed in the servo saver mount.

Or some combination of the three...

45mph pede

I checked everything today, double checked also. It seems that the screw is just poking out there so that it rubs on the cvd.

I followed the directions perfictly greased everthing good, and applyed lock tite were needed. I have no idea what the problem is with the flexing. Im about to contact HPI just to see if anyone eles has had these kind of issues. Thanks for the help!
-Wes

×SlappY×

wut motor u got in that thing to go 75 mph? [>:]

aliens8mycow

He's gonna blow up a novak ss5800 esc... [X(][X(][X(]

45mph pede

^Yup^ fastest novak ss on the east coast!