diff oil weight for Hyper 7 PBS
 

I'll be recieving my Hyper 7 PBS this coming Wednesday. It is my understanding that the diffs only come with grease in them. It is also my understanding that it doesn't take long before the grease disappears. Therefore, I'd like to put oil in the diffs before the first run.

First of all, do I need to remove all traces of the existing grease, just wipe off as much as I can, or can I just add oil on top of the grease?

Does the oil go in the actual diff itself?
http://members.dslextreme.com/users/...der_diff_c.jpg
http://members.dslextreme.com/users/...r_diff_f_r.jpg


Or does the oil go between the case and diff?
http://members.dslextreme.com/users/.../diff_case.jpg

OK, now let's get to oil weights. I would like a neutral running buggy, but I think I'd rather err towards a setup for a track with sharp twisting corners than a wide open track with gradual corners. Since I'm a newbie to 1/8 scale buggies (I've run an electric RC10 buggy and a Losi GTX stadium truck), I obviously don't want the buggy too squirrely.

I was thinking 3 - 7 - 1 from front to back, but of course I'm certainly not an expert, so I would like your opinions on the best starting setup.

Thanks for the help.

Roy

RE: diff oil weight for Hyper 7 PBS
 

roy - okay. heres the scoop.

1. Removing all of the grease isnt manditory, but get out as much as u can. simply squirting some nitro cleaner inside the diff will help get it all out.

2. you have to open the dif itself. this is where the oil goes. fill it almost to the top and secure completely. make sure u spary the outer parts of the diff with nitro cleaner, to remove any oil that has leaked out. it will attract dirt.

3. For a std buggy track here is what i use:

Front - 10,000wt
Center - 5,000wt
Rear - 7,000wt

This setup has worked great for me at 90% of the tracks i race at. if im racing at a very small 1/10th size track, i might drop to 5,000-1,000-3,000 - but it better be TINY.

RE: diff oil weight for Hyper 7 PBS
 

Wow nitroaddict that a thick pizza pie?
Why do you run the center so loose?

I run 5-7-1 in my h7

RE: diff oil weight for Hyper 7 PBS
 

the tracks down here in FL are pretty dusty and loose, scale - so i like having the center loose and able to transfer power easily. plus, with the center diff that loose, and pretty much makes the buggy rear wheel drive when accelerating, and this make coming out of the corners alot faster.

RE: diff oil weight for Hyper 7 PBS
 

What type of driving is your 5 - 7 - 1 setup tuned to scale_only_4_me-RCU? Where do you run at? I've heard that Revelation Raceway is best track near us. I could probably get there in 30 minutes from my house. I'd like to tune my PBS to that track if it is the best. I've heard good things about The Dirt in Hemet, but that's farther than I'd like to drive. I've never raced, but the idea sounds fun. However, my wife will probably kill me since I already have to many hobbies as it is.

Thanks.

Roy

RE: diff oil weight for Hyper 7 PBS
 

Nitroaddict - Nitro Cleaner? Is this anything more than glorified carburetor cleaner, or electrical contact cleaner? What about using denatured alcohol? I won't be using brake cleaner because that's a lot more agressive.

Thanks.

Roy

RE: diff oil weight for Hyper 7 PBS
 

Roy - yes, when i refer to nitro cleaner - i mean denatured alchohol.

RE: diff oil weight for Hyper 7 PBS
 

I run 5-7-1 also (per the Ofna manual) at our indoor track. It's tight, technical and there is a lot of traction. I've found this setup to be ok on surfaces that don't have a ton of bite to them, but on a short, tight track, the low speed steering is less than perfect. The car has a tendency to push wide exiting the turns. I've had somebody suggest that 3-3-1 or even 3-5-1 might be better for my particular situation.

RE: diff oil weight for Hyper 7 PBS
 

Oh what do you know dagass? All you do is hit ramps anyway.:D Seriously though, thanks for the advice. It almost sounds like setting up for a tight, twisty track would work in ALL scenarios. The car might not accelerate as fast as the cars with thicker diff fluid, but it wouldn't hurt you though would it? I guess the car would be a little tough to control though. Am I correct in this thinking?

Roy

RE: diff oil weight for Hyper 7 PBS
 

yes - the generic reasoning is that the thinner the oil the better the car will turn, but the more difficult it will be to drive. u will also have a greater chance of diff unloading

RE: diff oil weight for Hyper 7 PBS
 

One thing I can tell you for sure Roy, is that the 5-7-1 works GREAT on the ramps!:D After this weekend, I suspect there will be a whole lot less "rampin" and a whole lot more "racing".

RE: diff oil weight for Hyper 7 PBS
 

Nitro Addict - Exactly what is diff unloading?

I tried four different drug stores all withing 300 yards of my work, and none of them had denatured alcohol. Where can I get that stuff and how big a bottle can I get it in? Oh, and how expensive is it?

RE: diff oil weight for Hyper 7 PBS
 

If your just bashing then Nitroaddicts set up might work better for you, since it work well in loose conditions. 5-7-1 is more for a clean wet race track condition

Honestly I'm no pro racer, I use that set up because a few guys I race with that are more experianced recomended it for me, and it's what they run in there H7s.
The loose rear diff helps prevent the rear end breaking loose to easily, I'm told

I don't race my H7 as much as I race 10th scale truck
I mostly race at [link=http://www.hotrodhobbies.com/]Hot Rod Hobbies[/link] or [link=http://www.kzspeedway.com/racepage.htm]KZ speedway[/link]

If you're in Corona you should try LPRP (Lake Parris Race Park) also, they race Friday night (if enough guys show), Saturaday and Sunday 2pm. The track is right off Romona express way & the 215 right below Lake Perris

Alot of very good 1/8th scale guys there [link=http://www.lprp.com]www.lprp.com[/link]

Cya

RE: diff oil weight for Hyper 7 PBS
 

you can get denatured alcohol from places like the home depot, lowes, ect ect

RE: diff oil weight for Hyper 7 PBS
 

In some countries - denatured alchohol not available...[:@] One thing I miss is Home Depot and Lowes. [:o]

RE: diff oil weight for Hyper 7 PBS
 

roy - u can get DA at any hardware store, or ur LHS. it costs about 9.00 a gallon or 4.00 a quart

At some points on a race track, the inside wheels can lift up because of high cornering forces. This causes a normal gear diff to transfer all the available power to the wheel that is in the air. (For an example of this, pull the throttle gently on your car while holding one tire - all the power at that end of the car will go to the opposite, free, wheel.) This is because the differential will put any power at the wheel that is the easiest to turn. This is called diff "unloading".

RE: diff oil weight for Hyper 7 PBS
 

Hey guys, I have a blizzard goin' on outside my window right now! I'm thinkin' maybe I'll try my X-Terminator out in the snow...Do ya recon a similar diff. set up will work as for the slick tracks?

RE: diff oil weight for Hyper 7 PBS
 

Here in Atlanta at R/C Toys for Boys the popular diff setup is 5-7-1 (front to rear). I have this in my MBX-5 and I'm pretty happy with it. The track is ususally hard packed and loose on top.
The buggy pulls well out of corners, automatically straightens out on the straighaways, and steers well in corners.

RE: diff oil weight for Hyper 7 PBS
 

What kind of setup should I use for this Kind of track?

RE: diff oil weight for Hyper 7 PBS
 

use water, oil is too thick</p>