Crazykev's mega basher Yeti

[Crazykev]

The paint I used on the wheels was Rust-oleum Professional High Performance Enamel Aluminum 7515. Got it from Home Depot.

Bad part is that I've already cracked both rear wheels running the truck in 26 degree weather. I've always wanted to stay with light plastic wheels, but it looks like I'm going to be forced into running aluminum wheels just for the durability I'm looking for. Gonna eventually get a set of the Gear Head RC 2.2 lightweight U4 racing wheels and the VooDoo U4 tires. I just hope that glue will actually hold the tires on? Really liked how these wheels turned out! Sucks

 

[Crazykev]

Changed my fuel box cover plate up a bit. I figured that not only is it lighter, but 10X more rigid than the factory plastic cover, so I wanted to make use of that. If you grab the two shock towers in the rear and squeeze them together you see that they are a little flimsy. I made two ABS "bosses" that are epoxied to the inside walls of the box and also drilled a hole in them straight through them from the original side screw holes that are right behind the rear most shocks. Replaced the stock screws with ones that go the full depth of the ABS blocks I epoxied to the box. Lastly drilled holes in the cover and down into the blocks. There is about 3mm between the two screws where they intersect in the boss. Forgot to take pics of the inside and will the next time it's apart. Doing this beefed the shock towers more than I thought the cover plate ever would.








This last pic shows the rear most tab in the CF plate, showing the little double layer of the tab to make it lock into the box just like the plastic one. This isn't just a carbon fiber flat plate cut to the same dimensions as the factory plastic cover. This took a bit to get right, but it's perfect and the lower cf triangle is epoxied to the cover plate and sanded to the thickness needed to seal up the box without distorting the fuel box. The plastic one would flare up at the side edges and really never totally seal the box. My CC BEC is inside the fuel box, so I would like to have it as close to sealed and I can.





Adding the little plastic blocks in the box probably ate up any weight savings I may have had with just the CF cover plate on it's own, but I love how now the plate I made is not only way stiffer than the plastic plate, but a structural part of the rear subframe. You couldn't bend that CF plate with your hands no matter how hard you try.

 

[Crazykev]

Went ahead and ordered some new wheels and tires due to the plastic ones breaking. Gear Head wheels, VooDoo U4 blue compound tires and Crawler Innovations Duece's Wild foams.



I got the tires / foams first and mounted them up on the plastic beadlocks. I ran them for a while and they are amazing! Only thing I don't like is that the truck is actually slower and I believe that is because I went with standard size foams. Ordered a set of the taller ones for use on the new wheels and will glue them up as soon as my foams get here.

 

[pro mod steve]

AWESOME build I love the detail.

 

[Crazykev]

Off work for a couple days and decided to repack the rear diff fluid. This 2,000,000wt is awesome stuff! Not quite as stiff as silly putty, but way more consistent.



I know I've kinda dogged on the Acer ceramic bearings and want to make sure I'm clear that they work GREAT if they are in no way exposed to the elements. The bearings inside the axle housing are still smooth as silk and are actually better than the yellow Boca bearings for this application because they have less friction due to being a no-contact seal design. Just don't bother using them where you can see the seals after assembly. The Boca Yellow seal ceramic bearings have a far superior seal design for keeping the dirt out. In the end, I have a better bearing setup than if you went all Acer or all Boca, but if I did it over again I would just go with the Boca bearing set. Some may say that $150 is a waste of cash, yet they are running $300 in just wheels and tires on their rig. I think it was money well spent on bearings that will last probably the life of the truck. I'm amazed with how much abuse my rear ring and pinion survives through! I honestly saw a drop in motor temps when I went to ceramic bearings.

My taller C I foams should show up today and can't wait to glue up these tires to wheels that won't crack! I also ordered a Tekin Pro4 HD 3,500kv motor yesterday along with an 18t pinion. Dropping a tooth on the pinion due to the higher Kv and still should see a couple MPH top speed?

 

[Crazykev]

Also got the CI foam bumper insert

 

[Crazykev]

I'm an idiot for not waiting over night for the glue to dry, but oh well, the glue will eventually wear off. Holy shit this setup is bad ass!!!! The difference between the standard size and tall foams is just crazy! The tires do not balloon out at all and this thing handles something wicked now! Love it all the way around. Having the truck almost an inch wider than stock along with tires that are pretty much stretched around the foams is just freakin' beast!

This is a new tire with no load on it next to the U4s that are stretched over these foams.



Yes the glue slung around the tires looks like total shit and I hope it wears off. I had no idea it was doing this being that I was running it right as it was getting dark. Still think it looks killer! I can't get over how much different the truck handles now. Honestly I didn't like these tires with the standard size foams at all and regretted getting them until this last run.



Mounting the tires with the taller foams was a total pain in the ass too.

 

[battery]

Yeah, that looks freakin awesome! Best looking wheels for the Yeti 8) Can't even blame you for wanting to run it with wet glue

 

[Crazykev]

Even worse was that I ran it in the snow too, so the glue insta set once it hit water. I cleaned them up and a good bit of it came off. They should look fine after being worn in. I went to town with the glue because I doubted that it would stick to the aluminum very well, but they are holding great.

 

[Crazykev]

Besides going crazier with the motor setup, I think I'm done with this build. My bodies will always look beat and only stay nice for a short while. Really happy with this truck now and still have my Tekin Pro4 HD to throw in this weekend hopefully. I think it looks and runs killer as it sits.



I know it could use an aluminum truss in the rear, but I am a firm believer that something in the suspension has to be plastic to absorb shock loads, so it's staying.






Love how wide the track is!

 

[Crazykev]

This should have been one of the first things I did to my truck! I'm blown away at how much nicer sensored motors are! I beat on this motor as hard as I could and it just barely gets warm! I stepped down to an 18t pinion because of the higher Kv, but now want to try a 20t. This thing rips now!!!!

 

[Crazykev]

Last of the drivetrain upgrades. Rebuilding the front with Dlux modded case, Boca ceramic bearings, HPI spider gears and HD outdrives.

 

[Jubes]

like it,"thumbsup" "thumbsup"
am going to do the double rear shock upgrade myself and if i can find a nice looking set of dampers with the right dimensions i'm thinking of doubling up at the front too (simple mounting idea will stay secret until i unleash the photos...:mrgreen:

also if i can find a peice the right shape i'm actually thinking of going to 3 sets in the rear for a full 10 shock yeti

 

[Crazykev]

Something I do on all my RC cars is to drill access holes in areas for quick access. In this pic, I drilled a hole so that I can add grease to my front diff and cap it with a 4mm grub screw. I would also normally do the same for the rear, but the yeti has a nice access plate. I add grease to both diff gears about every 10-15 runs. I don't add much because most of it will get slung off and cause the diff case to leak grease making a mess and attracting dirt.



Take out the grub screw and squeeze the gear lube in with a syringe while slowly rolling the truck backwards allowing it to spread around the ring gear. I do have to take the front body mount post bracket to make it easier, but that is just 2 screws and you can fill the diff with it on except that it makes a mess.


Another one I have on the Yeti is in the chassis so that I can access the screw that holds the arm to the steering servo.

 

[Crazykev]

OK, so I guess I'm not finished with the truck yet. Only thing that I have been breaking on the truck has been the servo to steering linkage. The rod kept pulling out of the end links. My Lundsford 3.5mm Ti Punisher turnbuckles showed up today. Couldn't have picked a better length. Just about full thread engagement into the end links. There is no way this rod is being pulled apart again.

 

[Crazykev]

I should have went with my gut on these HPI gears. The HPI cars that I have worked on for friends over the years always seemed super cheap, so I was surprised to see that everyone considered their spider gears an upgrade over the axial. I rebuilt the rear diff last night and put in the second set of HPI gears I had from rebuilding the front diff (2 sets come in a pack). Took the truck out to run it today and within 2 minutes, the rear became one wheel drive, but with the diff locked. The gears shattered! Never had this happen in any of my cars.





The Axial gears are a better design! For one, I haven't had a single Axial diff failure of the internal spider gears and threw in the HPI set to see if the wider tooth profile would make the diff a little stiffer with the 2,000,000wt fluid. Typical HPI garbage! Removing the gears out of the front diff next time I have it apart. The HPI side gears are thinner and weigh probably 1/3 less than the Axial ones. Each one of those gaps behind the HPI teeth where you can see the thrust washer behind it is a massive failure point! I honestly thought they looked like a crap design when I received them, but figured everyone says they are the shit and an upgrade over the Axial ones. THEY SUCK!

 

[Crazykev]

That GCM diff case is bomb proof! If this would have taken place in a plastic diff case, it would have broke for sure taking out the brand new ring and pinion I just installed. It's an expensive one, but well worth it! I don't see how you could possibly make a stronger case except for making it steel instead of aluminum, but as you can see, that isn't needed at all. I run their diff with only one thrust washer on the aluminum side and not on the side that rides on the ring gear so that I can build the diff without a gasket and use Ultra Gray to seal it instead. That eliminates any bit of runout that the gasket can produce in the R&P gear mesh. I shim the case side to compensate for the slightly narrower assembly. It's the ultimate in a beefy setup!

 

[twisted]

did you make that front skid plate?

 

[Crazykev]

Sure did brother! I had some scrap 1/8" carbon/kevlar plate left over from a project on my WRX.


Maybe I am running into bad luck, but the Dlux front case ruined a brand new HD ring and pinion after 3 runs!!! I'm trying to not be a dick about it, but it's a bad design. The hole is drilled offset for the larger bearing skewing the tip of the pinion closer to the ring gear and by doing that, the load isn't spread across the tooth face. The case I got was WAY too tight! Another thing is that you shouldn't make the mesh really tight so it eventually will loosen up and be correct. You set it correctly and shim it if it ever does loosen up. The way that they are modded makes it so that you will never have a correct mesh. I reshimmed the old gearset with new bearings and the HD outdrives and put it back together. It lasted 4 months in the truck and will probably do that again.

If Dlux would offer cases that only have the hole enlarged for the bearings, then I would buy one again. Moving the bearing centerline on just one of the bearings is a really bad idea. Do it to both or the better idea is to not move them at all and offer it with shims.

 

[Crazykev]

My SMC 7200mah 11.1V battery showed up today. Fits like it was made for the yeti and is a little lighter than the Maxamps 6500 battery. It's a 60C and from what I have read, you can charge them at 2C. Even if it's way underrated and is 30C, that's still 216 amps continuous. At 60C that is 432 amps! It's raining today so I can't say how it performs? I don't think I even have to worry about breaking this battery in because beating the hell out of the truck will probably only put a 20C load on the pack. I need a better charger now for sure! Along with another one of these packs now that I know it fits.











I forgot to add that I swapped out the STRC bulkhead for a Vanquish one. The Vanquish hinge pin brace didn't exist when I installed the STRC. The STRC is going on the rig I'm building for my daughter.