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Im guessing all the top shafts come from the same place. Hoping that the bad ones are less common,, and a good one would be sent as replacement.

foots wrote:Too much saki on break.

I doubt they get breaks long enough to read one of his short stories.

gomachv wrote:I would also like to hear from someone with a rough trans that has removed the diff or topshaft to see which is causing the concern.

Those observations of mine were made with no diff installed.

gomachv wrote: The case may be holding the gears too tight but the shafts are being held at a constant, only the rotating parts can cause the feeling to come and go

This is true, and also why I sited my b4 shaft being fine in the b4 trans, but rough and intermittent in the new case. I suspect that NOTHING is perfectly round, ever. But with enough distance between each gear, the out of round isn't noticed. Think of your too tight pinion/spur. It's pretty okay most of the way around, but when it gets to the tight spot, binding occurs. Terrible! This will overheat a motor! But the same gears not so tight are perfectly fine, even though there is still technically a tight spot.

knowing the diff is out helps, with the diff in and the top shaft out I assume it spins freely?

foots wrote:Too much saki on break.

??

Drinking saki on a break would indicate that these are Japanese made, wouldn't be any quality issues if that was the case

I was thinking the same thing,,but dunno whats the equivelent of sake in the peoples republic??

mtbkym01 wrote:

foots wrote:Too much saki on break.

??

Drinking saki on a break would indicate that these are Japanese made, wouldn't be any quality issues if that was the case

This made me LOL.

mtbkym01 wrote:

foots wrote:Too much saki on break.

??

Drinking saki on a break would indicate that these are Japanese made, wouldn't be any quality issues if that was the case

You can have quality control issues in any country!

Especially Socal on a Friday afternoon!

gomachv wrote:knowing the diff is out helps, with the diff in and the top shaft out I assume it spins freely?

My 2cents the diff in mine spun fine.when I had the topshaft and idler in with out the diff gear is when I noticed the problem.and as stated here there is a low spot where its harder to turn.my re re worlds was so bad I couldn't spin it at all.which is why I started checking the gears in the case to see which ones where the problem.if you check the spacing in the re re worlds even with dail calipars you can see the shrinkage.and that's the main problem why the case and gears don't like each other.and over time and production it will get worse.unless it is fixed.even those the gears aren't perfectly round per say having a running clearence is what's needed imo.if .003 clearence is the general rule for a pinion gear to spur gear is the norm and then you still check for low spots then that is also what's needed here as well.when I checked the rpm case for the bearing spacing to map for making one in aluminum I used 3 cases.2 were new one was used.and in all three using a starret last word indicator I found all three with in .0005 .to me that's gold and very good mold making and quality control.concidering all three where brought and stored for years before I ever got them. Just think of what its like when making them out of aluminum is like when machining.lol at least keeping tolarances is a little easier to keep that way then molding them.and then trying to perform a q.c. now the rpm bearing holes did run a little out of round but nothing that made me worry I wouldn't have a good set of numbers to work with.sorry for the story just my 2 cents.oh and thank you sir for taking the time to show what you found so some can see the issues and maybe help someone fix theirs.

Okay, an update. In my drill press I ran the top shaft against 600 grit emery at 620 rpm, probably 12 passes with fresh paper each pass. Also about 6 passes on the idler, enough to see plastic on the paper. Then I put 1/2" of toothpaste on the gears, ran at 3200 rpm while filling the case with water (bye bye bearings), repeated 3 times. Then I ran it for 15 min with stealth diff lube.
My theory is that after sanding the o.d., the teeth can no longer bottom on each other, so the only binding is a result of the face of each tooth being forced against its mate.
My trans has gone from really bad to almost passable. There is still a distinct tight spot.

Problem with grinding or polishing gears is then there is less material to transfer torque. So, its quite possible that reducing gear tooth area MIGHT result in lowered ability to hold up to high power or even medium power systems. MIGHT. I do remember back in the day that a stealth required some break in,, but these reports of the new design seem pretty far beyond simple break in tightness. Luckily mine both are about norm for what I remember them to be,, except for the 1 top shaft.

Another option might be to try mix and matching of idler, and diff gears. If the LHS carries them cheap enough,, it could be possible to find some that fit and work, even in a mis shaped gear box.

has anyone tried using an another idler with the stock topshaft?

my method for fixing this would just be to power it out either way. I'd throw a gt idler in it and if it still had binding problems, run it till it didnt. It would just be the idler and top shaft though. Once it spins freely, put the plastic idler in and repeat. After that just clean it up and swap in new bearings. I did this with my 6 gear when putting metal idlers in. I probably ran them at a 25k rpm for a few minutes and it now spins smooth as can be.

Okay so I finally have the parts I was waiting for from Stormer.

Now that I'm assembling a Stealth transmission for the first time, I have a few questions:

1. per the instructions, is backing-off the diff bolt a 1/4 turn (from a fully compressed spring) the best tightness/resistance?

2. I now have 2 top shafts; a Worlds one and a B4. The flat spot on the Worlds one is noticeably longer and extends closer to the gear than on the B4 shaft. From the end of the flat spot towards the threads, they look identical

So without trial and error so that I don't have to thread lock and back out screws in plastic too many times, which one should I use right off the hop? Like I mentioned, the flat spot begins much further away from the gear on the B4 shaft. Will this give me the clearance I need? I've never built a Stealth and can't really picture the problem people have been having.

Also, FTR, the idler that came with all the Worlds parts barely spins the transmission. If I swap in the one I just received (6570) it's butter.