6LikesSchumacher Mi4
08-31-2011, 05:05 AM
#2956
Ive found that minimal grease works better than slathering it in there like in the Grainger Video. Here is a link to a good rebuild article when the Mi3.5 was out. Diff is pretty much the same these days anyway's. I was getting around 30 runs before rebuild in boosted stock doing it this way.
http://www.actionrc.com.au/downloads...ateMi3Diff.pdf
As for the Springs the pro 4 springs are the ones everyone uses. I have found Xray springs much better with either 2.8 all round or 2.8f/2.6r an awesome combo and on my home track kit springs are also faster than the Hpi's. I have found the HPI's to be a waste of my money...
http://www.actionrc.com.au/downloads...ateMi3Diff.pdf
As for the Springs the pro 4 springs are the ones everyone uses. I have found Xray springs much better with either 2.8 all round or 2.8f/2.6r an awesome combo and on my home track kit springs are also faster than the Hpi's. I have found the HPI's to be a waste of my money...
08-31-2011, 11:30 PM
#2957
diff building instructions that were posted a while back that I had saved on another thread...
The following is Diff building tips, it was on the shouie thread but should transfer over to most if not all diffs
Try this and let me know if it helps...
Before starting think of diff building like cooking with chicken. The black thrust lube is the chicken and if you get it on the diff balls, rings or pulley your diff will get sick and DIE!
Before I start I clean EVERYTHING with motor spray.
Before I start I clean EVERYTHING with motor spray.
Before I start I clean EVERYTHING with motor spray.
1. If you havent gotten a U1954 Tungsten Carbide Thrust Bearing get one. Its better then the one inculded in the kit.
Clean it all out and use Schumacher Black Thrust lube. Measure the outside diameter of the thrust washers. The small diameter one goes on the screw first.
Go wash your hands and get every bit grease off your fingers.
2. Sand U2408 diff rings with 600 grit wet dry on both sides using motor spray to wet the paper until you see even scorring of the rings entire surface.
Clean them with motor spray and place them on a clean paper towel.
3. Toss the ceramic diff balls. The U2459 Tungsten Carbide diff balls are smoother and longer lasting. Place the balls on a clean paper towel and CAREFULLY spray them with motor spray to get rid of any protective oil that is on them. If you spray too hard you will launch $15 of diff ball all over you room and they will be gone forever. When they are clean and dry put them in the tub of U1301 Silicone diff grease. Pluck them out and place them in your diff pully. Thats all the grease you will need.
4. Gradually tighten up the diff untill one output starts to spin opposite the other one. Gradually tighten the diff a little then spinn it a little untill you feel the diff screw has colapsed the spring washers next to the thrust bearing and it dosen't want to turn anymore.
The goal is to tighten the diff but not pit your freshly sanded diff rings.
5. Loosen the diff 1/4 turn then lock down the grub screw on the opposite side.
6. Put the diff in your car and turn everyhting on. wit the car up on a car stand. Run the car at low throttle while alternatly touching each rear wheel untill it stops. Repeat this 2-3 time per side.
The diff should be super free, super smooth and should not slip at all.
If you diff slips just once during a race it will score your rings and it will be junk. You will have to rebuild it and flip, resand or replace the rings.
The U1954 thrust will last longer than yuor kit so it will never be the cause of diff problems. The U2459 ball will survive at least 6 months or more. The only things that go bad in a diff assembled with these parts as described are the rings and you can resand them several time before you need to replace them.
Adrian Martinez
BMI Racing
bmiracing.com
DB12R NOW AVAILABLE!!
The following is Diff building tips, it was on the shouie thread but should transfer over to most if not all diffs
Try this and let me know if it helps...
Before starting think of diff building like cooking with chicken. The black thrust lube is the chicken and if you get it on the diff balls, rings or pulley your diff will get sick and DIE!
Before I start I clean EVERYTHING with motor spray.
Before I start I clean EVERYTHING with motor spray.
Before I start I clean EVERYTHING with motor spray.
1. If you havent gotten a U1954 Tungsten Carbide Thrust Bearing get one. Its better then the one inculded in the kit.
Clean it all out and use Schumacher Black Thrust lube. Measure the outside diameter of the thrust washers. The small diameter one goes on the screw first.
Go wash your hands and get every bit grease off your fingers.
2. Sand U2408 diff rings with 600 grit wet dry on both sides using motor spray to wet the paper until you see even scorring of the rings entire surface.
Clean them with motor spray and place them on a clean paper towel.
3. Toss the ceramic diff balls. The U2459 Tungsten Carbide diff balls are smoother and longer lasting. Place the balls on a clean paper towel and CAREFULLY spray them with motor spray to get rid of any protective oil that is on them. If you spray too hard you will launch $15 of diff ball all over you room and they will be gone forever. When they are clean and dry put them in the tub of U1301 Silicone diff grease. Pluck them out and place them in your diff pully. Thats all the grease you will need.
4. Gradually tighten up the diff untill one output starts to spin opposite the other one. Gradually tighten the diff a little then spinn it a little untill you feel the diff screw has colapsed the spring washers next to the thrust bearing and it dosen't want to turn anymore.
The goal is to tighten the diff but not pit your freshly sanded diff rings.
5. Loosen the diff 1/4 turn then lock down the grub screw on the opposite side.
6. Put the diff in your car and turn everyhting on. wit the car up on a car stand. Run the car at low throttle while alternatly touching each rear wheel untill it stops. Repeat this 2-3 time per side.
The diff should be super free, super smooth and should not slip at all.
If you diff slips just once during a race it will score your rings and it will be junk. You will have to rebuild it and flip, resand or replace the rings.
The U1954 thrust will last longer than yuor kit so it will never be the cause of diff problems. The U2459 ball will survive at least 6 months or more. The only things that go bad in a diff assembled with these parts as described are the rings and you can resand them several time before you need to replace them.
Adrian Martinez
BMI Racing
bmiracing.com
DB12R NOW AVAILABLE!!
09-01-2011, 04:15 AM
#2958
"Before starting think of diff building like cooking with chicken. The black thrust lube is the chicken and if you get it on the diff balls, rings or pulley your diff will get sick and DIE!"
Tungsten Carbide balls are better than Ceramic. Good to know. I thought ceramic was the end all and be all of diff balls.
Going to finally get myself a Muchmore bearing remover tool. Been on my "Need" list for far too long. Mi4 hub bearings are 5x10x4 which would make them M5 size correct.
Tungsten Carbide balls are better than Ceramic. Good to know. I thought ceramic was the end all and be all of diff balls.
Going to finally get myself a Muchmore bearing remover tool. Been on my "Need" list for far too long. Mi4 hub bearings are 5x10x4 which would make them M5 size correct.
09-03-2011, 11:52 PM
#2964
with a 118 spur he must be using boost, and unless your using the same esc and setting his pinion info is useless
09-03-2011, 11:58 PM
#2965
different ESC & Motor but boosted 17.5 on a similar track. Just looking for a good starting point as I have been running un-boosted with my previous TC with an FDR of 5.64 and never ran boosted before.
Last edited by BrodieMan; 09-04-2011 at 04:23 AM.
09-06-2011, 12:03 PM
#2969
Also I have over 10 PDub hard front bumpers for the mi4/3/3.5 if any needs one send me a pm.
09-06-2011, 01:58 PM
#2970
Tech Addict
Marcos,
those things are as scarce as teeth on a chicken. Could I buy 2 of them? 1 for me and 1 for racer-x.
Rich
those things are as scarce as teeth on a chicken. Could I buy 2 of them? 1 for me and 1 for racer-x.
Rich
