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RS4 3 18SS two speed tranny not shifting

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Hmmm...I'll try it out again today and see. If its not shifting, i'll give it back to the tech to look at again.
 
Hmmm...I'll try it out again today and see. If its not shifting, i'll give it back to the tech to look at again.

I know with my tc3 it took a while for me to feel it shift while it was in the air. It was smooth in the beginning.
 
The shift is based on the centrifugal force of the spinning mainshaft. The second gear clutch hub is secured to the mainshaft with the set screw in the clutch hub. The mainshaft is directly attached to the front and rear diffs via the drive shafts so the mainshaft RPM is in direct proportion to road speed. When the mainshaft (and clutch hub) RPM gets high centrifugal force will eventually cause the arm in the clutch hub to extend out against spring tension (tension set by the adjustment screw). Remember as a kid riding those spinning merry-go-rounds in the park. The faster your parents spun you the greater the force you feel trying to throw you off the ride.

First and second gear are always spinning together, except second gear always spins faster than first. When the car is using first gear second gear just freewheels on the bearing. When the arm swings out it will catch a metal pin in the metal clutch bell that is mounted to second gear and this will engage second gear causing the mainshaft to spin with second instead of first. This engages second gear. First gear will now “slip” on its one-way bearing because it is spinning slower than the mainshaft.

The NTC3 uses a shoe-type of 2-speed. It will shift smoother than a clutch hub/arm setup.
 
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I just tested her out again. To me, it doesn't seem like its shifting into second at all. I may go back to the track tonight and have the tech look at it again.

The adjustment screw you guys are talking about in the bottom of the car, is the set screw where the hole is somewhat slanted, correct? Not the set screw thats straight up and down? What I did, was flip the car over, and held the spur gear while moving the front wheels. I was able to see the two set screws, but I hope I"m adjusting the correct one.
 
snowboardgeek1 said:
The adjustment screw you guys are talking about in the bottom of the car, is the set screw where the hole is somewhat slanted, correct?
Click to expand...

Yes.

Do not touch the other set screw (straight up and down one). The straight screw secures the clutch hub to the mainshaft. If you loosen that you will need to put it back on the flat-spot in the mainshaft. You can do it with the transmission in the car if you really know what you are doing, but it is easiest to do it with the transmission out of the car and partially disassembled. That set screw needs to grab a specific flat point on the mainshaft. All the flat spots line up, so if you see both set screws for the two output drive cups pointing up chances are the flat spot for the clutch hub is also pointing up (if the transmission was built correctly).

http://www.hpiracing.com/graphics/instr/n3ss/kn3_09.jpg
 
Ok great. I did not touch the other screw so I think I'm ok. I tried adjusting the other slanted screw, 3 turns, and I still can't seem to get it to shift. I mean, with my TC3 I feel a little kick when it goes into second. The tech swears the SS is shifting into second, but whenever I try it out, it does seems to get into a higher gear (the car goes from a low scream to a higher scream, but I have a feeling its just hitting its powerband and not second gear).

Thanks for the help Ross.
 
Got the car back. Seemed like the set screw (the straight screw) was loose. Its all good now. The car shifts perfectly, and you can actually feel it when the car is in the air. The car still needs to be leaned out a bit though. Lots of fuel and smoke coming out of the car at idle and the low end.

In comparison to my novarossi cx12 on my NTC3, the top end of the 18SS is a bit better. Definitely is a beast. But the CX12 has a better powerband...low and mid, there's no comparison. The CX12 outclasses the 18SS in these power ranges. But overall, the 18SS is a great car.

One question though...I'm trying to run 30mm rear foam tires, but the left rear tire is hiting the radio box. Do you guys run spacers? Any idea on what the part number is? I need to run foams at Sun Valley's race track. I wish I can adjust the rear suspension better. What settings are you guys running for your suspension?
 
You might find the 18ss to be more powerful after you tune it. I would expect the 18 to have better low end than the 12.

You need to run 2-degree offset foams in the rear to avoid hitting the radio box.
 
ahh i see. where did you get the 2 degree offset foams? I was trying to fit on 0 degree offset...of course it didnt work. whats your settings for the rear suspension as far as toe/camber/caster, etc.
 
P.S I went out and bought the primerless fuel tank. So much better than that crappy primer fuel tank.
 
I used Nitro Shoes. Front & rear available in 2-degree offsets:
http://www.brucknerhobbies.com/foam_tires.htm

Rear Toe used the 2-degrees knuckles. Rear Camber was set at -2 degrees. Rear Caster is not adjustable. I had the stock shocks, pink hard linear springs, and medium bar in the rear. Stock shock mounting holes, stock camber link positions. I used 38 shore fronts, 35 shore rears. I ran a Viper body and the car did not oversteer, it understeered a bit. I could make it oversteer if I turned while giving it more than 1/2 throttle.
 
I ran 0 degree wheels in the rear with spacers, but later changed to 2 degree offset on the rear only. I prefer a lot of oversteer. If I run a wide body I have a set fo 2 degree fronts, but mainly I use 0 degree on the fronts.

-2 on the camber is about what I run, but I do not have a set up board (yet) and I have only checked it with my MT gauge.

Snowboard, I might have time to make it over to La Mirada on Sunday for the public races.
 
I may race on Sunday at Sun Valley for the sportsman's class. Show up if you can.

Where did you get the spacers for the 0 degree wheels? How much? Do you think Hobby People will have it?

I'll see if they have the degree offset for the rears. Thanks!

Revo Rancher said:
I ran 0 degree wheels in the rear with spacers, but later changed to 2 degree offset on the rear only. I prefer a lot of oversteer. If I run a wide body I have a set fo 2 degree fronts, but mainly I use 0 degree on the fronts.

-2 on the camber is about what I run, but I do not have a set up board (yet) and I have only checked it with my MT gauge.

Snowboard, I might have time to make it over to La Mirada on Sunday for the public races.
Click to expand...
 
The spacers came with some 30mm wheels I bought from HPI. Try Hobbypeople and see if they have some sitting around you can have for free. A lot of people just ditch them so maybe they have a set just sitting around. Just make sure the wheels you use them with have enough depth at the hex nut fitting on the wheel to hold both the spacer and the wheel.
 
2 speed issues

Hey guys I've had the same kit for awhile now.. and i have tried everything to make it shift gear but i cannot for the life of me get it to shift:( I've tried adjusting the shift screw (2 - 3 turns, and in between aswell) and I've taken the whole thing out and re assembled it again and i still can't seem to get it to shift.

now I'm jusing the black spring because of the .18 size engine..

Is there anything else i could try to get it working?

regards
Purple_nurplez
 

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