Type Cby R&D Japan
The Yokomo Type C has a long history. It descends from the Type B and SD (shaft drive) which had many variations as touring cars and drift chassis. The layout of the chassis is very generic, yet -because of the long history- it got more and more refined. It is not a very complicated chassis and very easy to set-up. When you change a setting, the driving behaviour changes as expected. This predictability makes the Type C a favourite among beginners and advanced drivers for drift and stock touring cars.
The Yokomo Type C is an updated classic.
This article is not a manual how to build it or a test, it just gives some hints for people who are beginners in building a RC-car. The steps refer to the original manual.
Step 3 (page 6)
After the gears are in the bulkhead, check if they rotate smoothly. It is important that there is no grinding noise or they get stuck. If this is the case, open the bulkheads again and check if everything is properly placed. Are the small gears fully pushed on the shafts, did you include the 8x11mm shim, etc.
I usually add some silicone spray on the gears to reduce friction. It does not to have a big effect (if at all), but it makes me feel good.
Please take care when attacing the holders for the hinge pins. The bigger one goes to the rear. See photo below.
Step 4 (page 8)
If you want to change the spur gear, you do not have to remove the complete bulkhead. Push the steel shaft until you can see the silver pin which keeps the spur gear in place. Then use a small screwdriver to push the pin out. After removing the rear half of the bulkhead you can pull the steel shaft out and change the spur gear.
Step 5 (page 8)
When you make the bellcrank it is the first time you have to deal with turnbuckles. The kit contains a tool which makes it easy to get the plastic cups on the turnbuckles. See the photo below.
Turnbuckles have a left-sided and a right-sided thread. The right-sided thread is marked with a groove. It is a good idea to let all turnbuckles face in the same direction. So when the car is in front of you -rear towards you, front away from you- all the grooved sides of the turnbuckles should be on the right hand side. Not just for the bellcrank, but all turnbuckles on the chassis. This way it will be much easier if you want to adjust steering or camber later. You have to turn all turnbuckles in the same direction to get the same results and do not have to think each time if this is a right or left-sided thread.
In the photo below you can see that the center turnbuckle is mounted in the wrong direction: the groove faces to the left while the groove on the other turnbuckles faces to the right.
Step 6 (page 9)
You can remove the center shaft if you remove the plastic clip, and then push the input shaft on the rear towards the spur gear. You have enough space then to remove the center shaft. See photo below.
When you put the front chassis brace on the bulkhead and chassis tub, be sure that it snaps into place. It should fully touch the bulkhead and chassis tub. Check the circled areas in the photo below.
Step 9 (page 12)
For the upper suspension arms you have to use the longer (25mm) turnbuckles on the front and the shorter ones (20mm) on the rear. The clear area of the turnbuckles between the plastic parts should be 9.5mm on the front and 5.5mm on the rear. All turnbuckles' markings should face in the same direction (see step 5).
The holders for the upper hinge pins are marked with "F" for front and "R" for rear. Attach them to the front and rear bulkheads on the sides which face to the center of the chassis.
Step 10 (page 13)
I added some additional spacers on the front lower hinge pins to reduce play.
You can read more about shims here.
Step 11 (page 14), Step 12 (page 15)
When putting the ballhead caps on the lower suspension arms take care that you use the ones marked with a "F" on the front and the ones marked with "R" on the rear.
The setting screw for downstop is in the lower suspension arms. With this screw you can adjust how far the dampers can extend. For the first set-up the setting screw should be 2mm out on the front and 0mm out on the rear.
Step 15 (page 19)
If you build the dampers like explained in the manual, you will have short travel dampers.
Put the installation help (part A-A) on a piston. Then add the travel reducer (part A-D). Press this assembly in the damper body. Then pull the piston out again and remove the installation help.
If you do prefer long travel dampers, do not use part A-D. The piston might feel a bit loose but after you installed the damper in the chassis, it works fine.
Step 18 (page 22)
You can give the foam bumper a longer life if you melt the pores of the surface with a lighter. Be careful not to burn the foam. Just a bit of heat is enough to reinforce the surface. Move the lighter quickly over the surface. There should be no noticeable colour change and fumes. If you look closely you can see that the pores on the surface shrink a bit under the influence of the heat.