Mike sells 1/8inch bore Mod1 Pinions. He also sells the 5mm bore Hardened Steel pinions that are for use with steel spurs. I'm quite sure he will be able to make you a hardened 1/8inch bore pinion.

I already have the regular 1/8" bore Mod1 pinion, but it's for plastic spurs. But after reading posts where the hardened steel spurs don't last, I am hesitant to use them. I'm just trying to find a way to use a plastic spur on a diff that won't fit it. I might just email Mike and see what he thinks...

Ooo...this is going to be a pretty big obstacle...let me know what you do Brian.

Oh, I will. I emailed Mike to see what he thinks.

Great pics... cool.

Now I have a some questions....

1.How mcuh too short is the outdrive... with the kyosho gear shaved down? It looks pretty close. I wonder if it would work with the inside of the kysoho gear also shaved thinner (on the inside, the area around where the o-ring is)

That's an idea. I wonder how I'm going to do this while still making it perfectly even and flat?

There's actually one more measurement I need to take and post a pic of...

Nevermind the above pic..... you already said the stock bearing is 10mm.

Also I measured the stub on the kyosho which is right about 10mm. It's just a hair under 10 then tapers to just over 10. I wondered if you could use a spacer sleeve to make the stock bearing fit right on the kyosho... and fit at least part way onto the fat part of the stub. Just a little sanding on the stub and the bearing would fit. That would let the stock outdrive fit farther into the diff... maybe enough to work.

Make sense???

The problem then is that it's still a mod1 gear and you are using a MM. 1/8" bore mod1 gears are a pain... maybe Mike could hook you up with a spacer so you can use the 5mm gears.

I know that even if all that worked... the gear might rub on the diff mounts.. so you would have to do something to hold it from hitting the mount

Here's another picture showing the relative heights. Each spur is resting on a standoff of the exact same height. The standoffs are sitting on the gear mounting plane. You can see that I can't shave enough off the Kyosho spur for the outdrive to reach inside the diff enough, while still being able to use a bearing. Don't forget, I'm limited by the length of the outdrive, not so much the diff mount...

http://scriptasylum.com/forumpics/crtp5_diff_10.jpg

And even if I could get this to work, I'm still stuck trying to find a bearing...

Would be nice to replace the whole thing with a slipper diff with standard 48 or 32p gears. But I don't know one that would work at the moment :)

I think I would do the piggyback gear... with a 46t gear so you can line up the teeth perfectly and drill holes to bolt them together. It would look interesting but it would work great.

dude on ebay i saw a person calld like world of bearings he sells like frm R/C bearings to skateboards and so on.

Oh man - That is a real downer about that spur gear. I'm so glad you are posting all of this because it's nice to see everyone's feedback for when I start my project...speaking of which. Guess what I happened to track down at one of my LHS's? :027:

http://members.cox.net/gluena/crt05_3.JPG

I scoured the internet looking for one and hear it was in my back yard!
I know Brian already showed his next to his Jato but here are some more comparisons:
Next to it's big brother CRT
http://members.cox.net/gluena/crt05_6.JPG

And an 18t, GT2
http://members.cox.net/gluena/crt05_9.JPG

Like Brian I was thinking about a MM4600 or 5700 too but it looks like there are quite a few issues to work out with the metal spur and finding a 1/8 in bore Mod 1 pinion. Anyway, just some other thoughts:

Again just for size comparisons. Here is a Feigao 7XL and Maxamps 3S 4000 mah pack in place
http://members.cox.net/gluena/crt05_1.JPG

a 7XL on 3S, that will fly! it was fun in my maxx.. so it's fun in a 1/16th!

Oh yeah! I sent Mike an email about this last night and he said the CRT.5 is one of his "short listed" projects since he got one of these himself! :) He said he may have to make a custom spur setup or maybe another diff setup, but wasn't sure yet.

I still won't stop thinking about solutions, but at least there are others that have this now so I'm sure an ideal solution will present itself.

Riceman: Good for you! :) The CRT looks nicer in person doesn't it? So, when's yours going to be done so I can "borrow" ideas? :)

Brian, why not make a sleeve to use the stock bearing. Just make a sleeve out of some kind of composite to sort of fill the gap since you can't find a bearing the right size.