arapoda:

For the hardened diffs you will need to shim the left output shaft to put the diff gear closer to the input shaft(little copper shims in the bag). Put in enough that the diff does not move, but not so many that it binds. I have six in mine. I have had mine in for 4 months with no problems. With the old Pot Metal ones I had to repplace them every other race weekend.

The 18 CVR is a great engine and will totally transform your vehicle. The 18SS is a ittle slow off the line, not enough torque as the OS.

That is what I was thinking. The whole point of me upgrading the engine is to just get some stability. Everytime I go to run my MT2's I have to mess with the mixture. After about a tank in each car I get them right. The T15 does not seem to hold a tune at all.

When you say "left output shaft" (large gear?) and "input shaft" (small gear?) which do you mean?

I tried to shim the small gear, but the shims are bigger in diameter than the small gear so I don't see how this could shim the gear.

As for the larger gear within the diff case, I placed a shim according to instructions from djheptic on this forum (as posted above).

Here is a list of stuff I have bought and/or installed on my MT2. Just thought you all like to know my thoughts:

All in US Dollars

Small - Anything under $20:
OS Air Cleaner - Came with engine, its really nice
*Air Cleaner - Motor Saver two stage filter- $11.00
HPI Woven Graphite Front Shock Tower - 17.59
HPI Lightweight Flywheel - 17.59 (Love this flywheel, but not very reliable)
HPI Dodge Body - 18.99 (Just looks Better)
HPI Brake Disk FiberGlass - 12.99 (Stops better)
HPI Hinge Pins Nitro Set - 14.79 (Replace with SS parts)
*Tamiya 4mm Lock Nut - 2.49
HPI Aluminum Hex Hub 12mm - 17.59 (Stops the stripping of the wheels hex)
HPI Teflon Shock Inserts - 3.89 (Had these for my old original shocks, the threaded already have them)
HPI Gear Differential Adjustable Spring Set - 7.69 (Makes the diff act like a ball diff)
HPI Racing Clutch - 13.99
HPI Blue Front Springs - 4.79
HPI Blue Rear Srpings - 4.79
*Hot Bodies Aluminum Front Knuckle Arm - 19.99 (Discontinued, New from Powerline)
*Hot Bodies Aluminum Rear Knuckle Arm - 19.99 (Discontinued, New from Powerline)
Ofna 125CC Fuel Tank - 9.99
HPI Heavy Duty Cup - 6.69 (I thought these were stupid, but they actually last 5 times longer than stock)
HPI Heavy Duty Cup - 5.79 (Same as above)
Proline 2 stage Foam Inserts - 6.19/set (Much better than stock foams in all my tires)
HPI Savage Racing Clutch Bell - 14.79 (Needed with the Steel Spur)


Medium $20 - $50:
HPI Universal Dogbone Front - 28.99
HPI Universal Dogbone Rear - 28.99
HPI Sway Bar Set - 28.99
HPI Wheels 4 sets - 64.00 (I love having different wheels)
HPI S-Compound X Pattern Tires 2 sets - 50.00 (Gave them away they were alright)
Proline BowTies M Compound Tires 2 sets - 38.00 (Great on loamy Track)
Proline HoleShots M Compound Tires 2 sets - 34.00 (Great on Dusty Loose Track)
Proline Evil Twin R3 Tires - 36.00 (Great on Smooth Groomed Track)
Losi Pink Taper Pins - $36 (Best tire for Groomed track - Put a little Buggy Grip on the tires let them sit for a week and the stick to anything)
HPI Woven Graphite Rear Shock Tower - 21.99
HPI Titanium Turnbuckles - 34.99 - Needs HPI Heavy Duty Ball Cup - 7.89
THS Exaust - 49.99 (Better than the CVEC and is currently installed)
CVEC Exaust - 37.00 (Better than stock or HPI)
HPI Exaust - 49.99 (Hated it, got a CVEC)
HiTech 645 Steering Servo - 39.99 (What was I thinking with this one - turns SLOW. Got a better servo later)
HPI Aluminum Threaded Front Shock - 37.99
HPI Aluminum Threaded Rear Shock - 37.99
HPI Upper Deck Graphite Woven - 45.99
HPI Hardened Diff Gears - 32.99 (need two)
HPI SS Suspension Shaft - 17.59
Powerline Aluminum Steering - 22.79 (Broke immediately - went back to stock setup)
Ofna Reciever Pack - 25.99
HPI Super Chassis - 37.99 (This with the CF upper chassis brace makes it super stiff)
HPI Savage Steel Spur Gear - 47.99 (I prefer this over the nylon reinforced, ut could be argued)


Large > $50:
HPI .18SS Engine - 144.99 (Got tired, sold it)
O.S. .18 CV-RX w/11J Rotary Carb - 99.99 (This thing got some b***s)
Airtronics 94758Z Competition Digital Hi-Spd/Torq Servo 99.99 (Turns on a dime)

For the SS stuff I just broke down and bought an SS Kit to get the parts then sold the 18SS motor.

Just a running list to see what mods I have installed and some notes on them.

I starred the items I think are the most needed for reliablity.

arapoda:

The large gear. The shims fit between the bearing and the gear.

I can't really see much detail in that image you've posted, so I've just taken two photos which I'll upload in a minute, give me a few mins...

Forgive my greasy nails!

Okay, so here's the small gear. According to djheptic's diagram, one shim should go where you see it here, so that it sits against the bearing. But, the hard diff gear is different to the pot metal one, so this shim is too wide.



And here's the output gear. I don't know which side the shim should go on - is it this side...(where the red dot is)
(You can also see the pot metal small gear in this image)



Or this side? (where the red dot is marked)...(Will one shim do? Or should I use two?)

arapoda:

Pic #3:

Pull off the big Gear then pull off the e-clip. Disassemble the output shaft and pull the bearing off. Add the washer from pic one to the outside of the diff gear (add 3 -4) then reassemble. The washers go inbetween the bearing and the big gear. If you go to HPIRacing.com that have the 18ss manual online. That is the picture I was trying to include.

Make sense?

What confuses me is that you have the pot metal input gear on the table and also the hardened steel one in your hand? Which one are you installing? The above is for the 18ss hardened steel ones. I hope that is what you are installing.

You need to put the shims on the GEAR SIDE between the bearing and the gear. This will move the gear closer to the pinion gear to get a better gear mesh. Don't over do it though because that will burn out the gear as well. When done correctly you should have a tiny bit of play. You can check this by holding the ring gear (the gear mounted to the diff case) and moving the pinion gear (the smaller shaft gear) back and forth, there should be a very tiny bit of play when it is done right.

Good luck,

Thanks for the info, guys. I'll see what goes.

The pot gear is on the table in the photo because I'm only just replacing them with the hard diffs. I'm not putting it back in!

Let me just check I'm getting this right, as this is an expensive mistake if not done correctly...



I need to take the black case off, remove the e-clip, take the bearing off etc, and place the shim so that it is sitting on the gear, then put the bearing back on, and everything else, then the black case, and that's it? How many should I use, as there's three shims in one pack.

I think I've gone cross-eyed! What I just said makes no sense as that would move the gear away from the pinion gear, no?

This is confusing everyone. YOU CAN'T TELL SOMEONE HOW MANY SHIMS THEIR DIFF REQUIRES. Every diff is different. That is why they send out shims! If they were the same for every diff then they would tell you how to put it together in the manual! Some will require 2 on one side and 1 one the opposite or the other way around. Some might only need one on each side.

If you have questions about shimming diffs email me at [email protected] and I'll try to explain how to do it.

What you said is correct. Here is a tip....

Take out the E-Clip holding the diff shaft on the gear

then mount the gear to the black diff housing using only 2 screws

Now you can pull out the drive cup and remove the bearing to add shims without having to take apart the entire diff assembley

Install the shims and put the bearing back in place

Then slide the diff shaft back in

Now you can place the diff housing in the gear case and check the gear mesh by holding the final gear (the big gear) and move the pinion gear back and forth.

If you need a refrance to all the parts I talked about click below for the manual.

http://hpiracing.com/graphics/instr/10441/10441.pdf

Sorry I cannot explain this any further I have to get back to work.

check it out [link=http://www.wolfpackradicals.com/html/shaft_2_speed.html]2 speed with clutch[/link] i got it of another thread but maybe thats what most of of have been looking for BTW nice looking truck nick looks like its gonna be a fun project

Woo-hoo, my tuned exhaust got shipped from Tower Hobbies today. I live in the UK, so if anyone from the UK has ordered from Tower, how long does it usually take? A week?

well here are the pictures as i promised u ppl. man i just broke the little throttle thing on the carb o well back to the hobby shop lol

where can you buy them, and i dont see a slipper

it all depends. towerhobbies let me down this time though. i live in new jersey and it look exactly 7 days for it to get to my friends house and i also paid extra for 2 to 3 day shipping because my friend orderd it 2 days be for i came over so we can play wit my car but it didnt come on time. my guess is alteast a week or more

i agree with mura... there is no slipper

hey i have a problem with my mt2 rtr. im pretty new to this. my throttle servo is all messed up somehow. is both the brake and throttle (upper and lower part of the servo thing) sopose to move backwards when i use brakes? and i cant adjust the throttle correctly. when i full throttle, the throttle lever on the carb is being pushed to far forward putting stress on it. same for when i brake. whats wrong? thanks in advance

sounds like you are not usint a servo saver spring

Hmm...I'm not sure of the exact problem, but I'll give you a tip - Make sure you haven't accidentally flipped one of the switches on your transmitter that reads either "ST" or the other switch that reads "TH". I accidentally knocked one of these switches last week and my throttle messed up completely.

Got a technical question for those who own a O.S .18 CV-RX engine.

Brand new O.S engine...

I've taken all the parts off the T-15 engine, flywheel etc.

Out of the box the O.S engine has a piece of round metal on it that covered the bearing (circled in red). Does this stay on the engine shaft? Or have I done this correctly and taken it off, and placed the brass cup (along with the small black plastic washer) directly over the engine shaft, covering the bearing?



Thanks. It's probably wrong, knowing me!

You are right, leave that piece off, slide your brass collar on the shaft then your flywheel, make sure it is seated on that collar pretty good. You should not be able to spin your flywheel without turning your motor.

Thanks a lot, man. Much appreciated.

I've hit the part of the job that I have not been looking forward to - Attaching the racing clutch. For now I'm not going to cut the clutch as it says you can do in the manual, I'm just going to leave it as it came in the packet, BUT...I'm having REAL DIFFICULTY looping both ends of the spring together. Just when I think I've looped both ends and crimped them successfully, I go to stretch the spring around the clutch and it pops loose. NIGHTMARE!

Any possible tips?