F N CUDA

iTrader: (34)

I think you meant F103GT gearbox?

The F104 is different but will work, bolts right up and the hop up is aluminum on both sides.
I run it on my F103 til TCS Regionals.

Couple problems with it tho,

1. Not Tamiya legal as a hop up for the F103 now (was ok last year tho.)

2. It repositions the axle higher in the gearbox/side frame lowering the rear of the chassis more so it doesn't allow you to run smaller diameter rear tires.
I think 52 to 53mm is about the limit (off the top of my head) then the chassis drags.
There is a mod I did to allow more adjustment if you really want to run it.

PM me for details if you're interested.

Not sure who else to check to get the F103 gearbox tho.

I can usually find stuff in the random ebay stores like,

RCSausagedog.com
Jasonrc.com
...
I just look around and when I find any F103 parts listed I check their store.
You might be surprised who has hard to find parts.

k_bojar

iTrader: (30)

yes, i meant the F103GT gearbox - silly typo

I've thought about using the F104 aluminum parts, but I'd still need the ride height adaptors (the reason why i wanted the F103GT gearbox )

I'll probably end up running rubber tires on the car this summer - and won't hit any TCS races until next year at the earliest...i do have a gearbox pack coming in from overseas, but haven't heard anything back yet - so i was looking for a backup just in case

I guess in the worse case, I can run the original plastic gearbox i have currently - i just won't be able to use the aluminum motor mount until I find ride height adaptors...it will work, but not the idea situation i was looking for

F N CUDA

iTrader: (34)

So you have the fixed axle gearbox, I see the problem.

j.d.roost

iTrader: (32)

..

k_bojar

iTrader: (30)

yuppers - which is fine, it just means I cannot use the 'fancy' aluminum motor mount...

i'll just cross my fingers that the one i ordered from ebay makes it here before I'm running the car

robk

iTrader: (22)

I am almost positive I saw this in stock last week at Harbor Hobby
http://www.harbor-hobby.net/ call and ask for Eric

Otherwise I was able to get them from RC Champ in Japan

zpmhinojosa

Earlier on 2-14-10...

+ YouTube Video

Enjoy!

chinaman

Hello

Can I check what spur gear are you guys using in your F103? My diff keeps slipping. Am currently using the standard AV 63T. I am using a HPI 20T sealed can. Motor restriction in my class. I have the option to get some Kawada M0.4 spurs which uses I think 12 ball bearings instead of the 6 in the standard Tamiya.

I think I have spent a fortune in modifying the F103 and have come to a conclusion (that I already knew a long time ago but refuse to accept) that it is the design as compared to other pan chassis out there like the Gen X and RC10R5.

But I still like the fact that I can take my GT shell off and just put some wings on and it is an F1 car

Cheers

InspGadgt

If your diff is slipping then you have something wrong in your thrust assembly. Often times this is due to something wrong with the spring washers that put the pressure on the thrust washers. Over time these spring washers go flat and no longer work properly. Also putting them on the wrong direction can cause problems with diff slippage.

Obsidian

iTrader: (10)

Hello all,

So I know the included spur in the 15 anniv. is 0.4 pitch 93tooth. My question is what is equivalent in 64pitch.

Also, what is a general spur tooth count that the majority of everyone is using. Cheerz

j.d.roost

iTrader: (32)

I think mode 4 is close to 48 pitch. So if needed you could crunch the numbers using 48 pitch as a guide.
http://www.robinsonracing.com/tips.html


Remember ratio is ratio 48 pitch 64 pitch it don't matter.
I am running 3:31 ratio with a silvercan (cut down foams).

I find using a 94 to 98 spur gives you alot of options with pinion size (64 pitch).

Oh and don't forget about rollout with foam tires! When you cut them it will effect things a bit.

JayL

most at my track run 64p 100t kimbrough spurs, they let you run 8 balls and normal pinions
just choose your pinion based on around 47-52mm rollout for silver can

j.d.roost

iTrader: (32)

Just watch that high number. We started toasting them at Horsham around 51. (high bite carpet)

chinaman

that was what i needed to know ... if i am using a 20T HPI sealed can, does that mean that i need a lower roll-out. I am currently running it at ... gosh 59!!!. maybe that is why i hear go eeeeek (diff slipping) all the time

F N CUDA

iTrader: (34)

What method do you use to set your diff?

Will your diff stop slipping if you tighten it, are you trying to run it loose?

Put it on the track, punch it, if it slips tighten it, if it won't tighten you have something wrong.

Put fresh spur gear, diff balls and rings $10 and fresh thrust bearing $5 more.

Repeat adjustment process

Newly freshened diff, PRICELESS.

My 27turn Cobalt brushed motor was stupid fast in this car, 20turn could be insane.