Looking to Upgrade Bevel Gears Next...

[alexchen86]

I'm looking into upgrading my ring/pinion setup on my Wraith kit build next...

So far this is my running gear:
Holmes BRXL w/CM 16T Handwound on 3s
CCBEC @ 7.4V on a waterproofed 7950TH
R35 2.2 Ripsaws
CI DD Soft/Med Closed Cell Foams
CAC 2.2 Aluminum Polished Beadlocks
Losi 4" Big Bores 25% droop rear 60wt all around 2 hole pistons
Losi Whites Front and Rear
DMG Aluminum Panels
R2J Stainless Uppers
Stock Kit Aluminum Lowers
Leftover Tamiya Tundra High Lift Decals for a chrome/black Tribal theme
CI Aluminum Cargo Cover
Black/Red/Chrome Interior working on carpet right now
Flip top hood mod
Front battery and electronics tray
Waterproofed all electronics
Axial Simple LED light system waterproofed 4 white 2 red all 5mm off RX
Robinson Steel Geared Tranny
Supershafty Wraith Beefy Top Shaft
Robinson Gen3 Slash Steel Slipper
Robinsion Steel Pinion
Lucas Red n Tacky #2 and White Lithium used where needed...


Now with all that it's obvious I'm trying to build a lightweight 2.2 TTC.

Next up are upgrading to the HD ring/pinion gears...not sure what combo to run since I use the rig as a go fast KOH style crawler and rock racer.

Do I get OD front and just UD rear like typical Axial axles or should I do OD front and just the upgraded HD gear set for the rear?

Or how about OD both front and rear? Lol....

[Harley]

OD and UD is a lot of bind, I would be carefully with that in the Wraith. I love that setup in my sportsman but wouldn't use it in my wraith. I would probably say HD read and OD front. That is likely what I'll go to soon.

[johnnyh66]

OD front HD rear

[Solitaire]

There's a slight gearing advantage to UD'ing the rear (stock ratio in the front), but only by a bit. .04 to be exact.
It's also easier to tear apart the rear end rather than the front. Just another opinion.

[ChronicCrawler]

Originally Posted by Solitaire

There's a slight gearing advantage to UD'ing the rear (stock ratio in the front), but only by a bit. .04 to be exact.
It's also easier to tear apart the rear end rather than the front. Just another opinion.

I would like to upgrade my wraith bevel gears but do not have a clear understanding of it. Should I just put in the same gears as stock? I go slow 90% of the time. I switch between 27T and 35T motor

[Harley]

Originally Posted by ChronicCrawler

I would like to upgrade my wraith bevel gears but do not have a clear understanding of it. Should I just put in the same gears as stock? I go slow 90% of the time. I switch between 27T and 35T motor

With a brushed motor, you really only need to upgrade the gears if you want to change the ratio. Otherwise, you really aren't going to wear out or break the stock gears.

If you are going slow 90% of the time, than going with an UD rear gear set would give you a little better turning and climbing performance.

[redsawacs]

My stock gears are worn out after 6 months with a brushed motor on 2s......I started to see tiny flakes in the case and a few tiny chips on the teeth as well as slop and now grey grease....yes, they are worn out.

UD/OD are all HD gears.....HD gears come in STOCK ratio as well....

I went to HD gears because of this. Since I do trail runs weekly, some crawling and very little "go fast" runs, I decided to overdrive the front end - HUGE improvement over the stock gears. But, this doesn't address the question at hand.

When and why to alter the gear ratios in the axles. Basically, if you're doing any crawling and your rig likes to push the rear end under itself and flip backwards, you are noticing a rear push due to the fronts not pulling faster than the rear is pushing. If you speed up the front wheels (OD) or slow down the rear wheels (UD), the rear of the rig will be less apt to drive under itself since the front tires are always pulling/moving faster than the rear. Keep in mind, having little to no traction in the front and the rear having plenty of traction (i.e. trying to climb up a rock and the front is trying to get traction while the rear tires are still on the ground with plenty of traction) will still result in driving under or flipping over. This is not a cure for that but it will certainly help when both the front wheels have equal amount or more traction than the rear.

Another idea behind underdrive gears is the mechanical advantage you will get on the drive train to turn the tires.....if you weight you tires heavily. Having UD gears will allow your drive train to work less to turn the weight of the heavy wheels and tires - cooler electronics. I would suggest this principle applies only to UD in both front/rear axles, as any other ratio in the rear would tend to "push" the rig past the front end....

Some choose to use UD in the rear and stock in the front, some choose to use UD rear with OD front, some choose Stock rear with OD front. I personally believe money drive decisions as much as application (how/where you drive). If you are a trail guy or basher with no crawling time, I personally offset ratios is a waste of time and money as it will give you no foreseeable advantage on flat ground but that is just my opinion based on my application.

Hope this helps.

[SteveC6R]

I use mine as a crawler and have the stock HD gears in front and HD UD in the rear.

[redsawacs]

^^That will do it

[ChronicCrawler]

So which bevel set is OD and which is UD ?

If i understand right I want to put UD in the rear for climbing

[allanon1965]

The 36 is OD.....the 43 is UD

[Postclanker]

Originally Posted by SteveC6R

I use mine as a crawler and have the stock HD gears in front and HD UD in the rear.

I really like that ratio, been running that in a lot of trucks....HD all the way

[evan03]

I would leave stock gears in until the need replaced.

Here's my gears these where shimmer and didn't have many miles yet. Usually I run a set of gears till the teeth a layer over.
The stock ready to run gears. The heavy duty as pictured and hot racing.

This gear went while crawling slow. A rear tire was bound harder then I thought.

What I'm saying is I normally get quite a lot of miles out of a gear set. I've ripped teat off a hot racing and now this axial gear. Normally they run quite awhile.

Good luck.

[alexchen86]

Originally Posted by Harley

OD and UD is a lot of bind, I would be carefully with that in the Wraith. I love that setup in my sportsman but wouldn't use it in my wraith. I would probably say HD read and OD front. That is likely what I'll go to soon.

After a SUPER long absence from RCC I'm glad to be back!


Yup commonsense tells me OD front HD rear. But if I am building a lot slow rock racaer I'd want equal ratios HD front and rear right?

Seems like a no brainer...I've been toying with an open diferntial front and a locked rear on my Orange Crush buld which is my twice on a BGR Wraith like Fiona but still keep it solid axle all around 4 link rear undecided on the front end.

Just something to bash on our local SCT track for goofs...

Suggestions?

[axial 4x4 crawler]

I would NOT leave the stock gears in because on my wraith I blew the front diff bearings and it literally chewed up the pinion gear so bad that it need replacement..yeah on a tekin 10.5t with 3s!! I'd recommend getting OD gears in the front and getting the regular H.D. Bevel gear gear set for the rear so then you won't have binding with a OD/UD setup.