Kyosho Ultima ST Type-R/Evolution GP custom gearbox covers for RB5 ball/gear diff and stock gears

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Make Kyosho Ultima ST great again... I created this custom gearbox, because i couldn't find original gearbox covers or the gears for the discontinued Kyosho Ultima ST Type-R/Evolution chassis. This gearbox bolts to Type-R and Type-R Evolution chassis and its designed around easily to get Kyosho Ultima SC/DB/RB5/RT5 ball diff set (part nr. UMW602). I wanted to prolong the lifetime of this vintage chassis. You can also use the RB5 gear diff if you want, this is also fully compatible with it. The left side gearbox cover also has a small access hole for easy ball diff adjustments. Cover this hole with screw or piece of plastic when you drive the car, so you don't get dirt inside the diff. You probably need longer universal joints than the stock Kyosho Ultima ST has, because RB5 output shafts are shorter than Kyosho Ultima ST. This uses stock brake piston (6x5mm if i remember correctly), stock brake disc (30mm diameter) and stock brake pads. I used Inferno NEO/VE/MP7.5 brake disc, brackets and pads (last picture). I'm not yet sure how long brake lever axle you need, because im fabricating my own custom axle from 4mm titanium. The brake shaft part that goes inside the gearbox is 20mm, the rest is what ever is needed for the part that sits on top of the gearbox. I suspect that the whole brake shaft needs to be 30mm long. I also created a ball bearing recess for the brake axle. That uses 4x8x3mm ball bearing. You don't probably need it, i can draw a plastic collar for people that don't want to use real bearing on that spot. Edit: Gearbox cover without bearing available in downloads. The idler axle needs to be exactly 16,8mm length. It is really tight fit with brake system. I did my own custom axle from 5mm titanium. I'm not exactly sure if RB5 input shaft works with this, because my car will use custom titanium input axle with aluminum 20T input gear (ARRMA AR310016 Idler Gear 20T). I left some space between the input shafts front bearing and the input gear to fiddle around with different gear styles. You need to shim it yourself with shim washers, depending what kind of input gear you use. I suspect that stock RB5 (UM524) main gear shaft should work, as i left so much space inside the main shaft bearing area, but i cannot confirm it, as i don't own the Kyosho main gear shaft. Please give a comment if you want to test it. I uploaded the modified right side gearbox cover, without ball bearing brake shaft. Its the stock style version that Kyosho uses. This is for those who don't want to fiddle with extra ball bearings. Enjoy and drop a comment how did it work for you, or if you want any changes to be made! Also check my other parts that i have made to Ultima ST Racing Sports/Type-R/Evolution chassis. Here are the links to my project: https://www.rcuniverse.com/forum/rc-nitro-stadium-trucks-243/11675757-my-ultima-st-gp-type-r-evo-20th-anniversary-project-3d-printed-cf-parts.html https://www.rc10talk.com/viewtopic.php?f=30&t=44634