USA vs China Stealth cases with video

[jwscab]

MiniMini's 4wd project used a re-re front case and a 26t pinion instead of the idler, and he says it's smooth:

http://www.rc10talk.com/viewtopic.php?f=35&t=35654&hilit=4wd

although all the pics are gone in that thread?

[Phin]

Kyosho KYOUMW513 might work if you ream out the idler shaft hole in the Chinese Stealth case from 3/16" to 5mm....or figure out some other way to adapt the metric shaft.

There's also an aluminum version. P|N UMW718.

[jwscab]

I was looking at this, but is it true 48 pitch or metric 48 pitch?

[Phin]

Not 100% sure but should be standard inch 48p. I haven't heard of mod gears being used much anymore outside of 1/16 and 1/18 scale or Mod1 gears for larger monster trucks.

[badhoopty]

so is it the idler or the topshaft in the re-re trans that makes it rough and bind?

i ended up using the diff from the re-re kit with everything else from a usa stealth kit. fyi out of the 2 usa stealth kits i bought, one of them had a bad topshaft.

im curious since i just got another correct b4 topshaft if i could try again with the re-re stealth and see if i can get it to spin. i'll throw it together when i get home and let you guys know. that should prove whether its the topshaft thats responsible for all the re-re problems or if its jsut the topshaft for the spur plate clearance and the idler for the horrible gear mesh.

all in all, im stoked that these parts and the re-re kit is available, but im also disappointed its not as nice a kit as the classic re-re was.

[GoMachV]

In my video I use the same diff and topshaft in all of them, it didn't appear to be any problem. Note that mine was properly machined for the slipper tho, so I can't say on the others.

As you can see in the video, once I replaced the idler it made all the difference. Back to being a whisper quiet and smooth gearbox

[dldiaz]

well, i'll go with you guys on that. it just doesn't seem right to me. i'll have that "light bulb" moment eventually.

Just consider the math. To get the final ratio of the 3 gears in sequence you can figure out the ratio of the idler and top gear and the idler and diff gear then multiply those two values together:

28/20 = 1.4
48/28 = 1.714285714
1.4 x 1.714285714 = 2.4

I struggled with this concept too, so I finished the math comparison with a 26 tooth idler:

26/20 = 1.3
48/26 = 1.846153846
1.3 x 1.846153846 = 2.4

So, when you change only one gear in a series of three gears,
the two respective ratios change in opposite directions.
i.e. - topshaft to idler becomes smaller, while idler to diff gear becomes larger

This allows the final ratio to stay the same - 2.4

[Phin]

Good point...showing how the trans ratio doesn't change if the idler changes.

Think back to math class.

Code: Select all

 I     D     D
--- x --- = ---
 T     I     T

I = Idler Gear
T = Topshaft Gear
D = Diff Gear

"I" cancels out.

[RC10th]

Well finally !!

I finally got some 6565 cases after ordering some from two different suppliers and getting 6564 cases instead. The color is terrible while the 6564 cases isn't too bad.

I managed to get 6564 cases to fit NIX10M mid mount in the meantime.

[romulus22]

Stepping on old ground here for the visual people like me. Not a math person.

Hold the top shaft in your left fingers. Diff in right fingers. Put any size diff gear in the middle. With the top shaft gears and diff gears as close without touching you can spin them and the teeth will turn at the same speed no matter the idler gear size. The idler is just a spacer.

[johnqpublic]

I'm in the middle of building a worlds car too. Mine seemed to have a bad top shaft. I put one in from an old T4 transmission I had laying around and viola! Smooth operation.

Overall, I'm a little disappointed at the quality of the materials compared to the old stuff, particularly the shock towers, and the almost greenish tinge on some of the nylon.

[SFC K]

I'm in the middle of building a worlds car too. Mine seemed to have a bad top shaft. I put one in from an old T4 transmission I had laying around and viola! Smooth operation.

Overall, I'm a little disappointed at the quality of the materials compared to the old stuff, particularly the shock towers, and the almost greenish tinge on some of the nylon.

Many of us have had the same complaints. If you contact AE they will send you replacement parts. Info on how to do this is at the link below.

http://www.rc10talk.com/viewtopic.php?f=88&t=34024&start=1320