Evo Clutch Drum Repair On a  2 Speed Gearbox




You will need the following tools

1)  5mm Allen Wrench

1)  6mm Allen Wrench

1)  10mm Open End Wrench

1)  Pliers

1)  7/16” Open End Wrench

2)  17mm Open End Wrench


1)     17mm Open End Wrench

1)     Adjustable Wrench

1)     17mm Socket

1) Digital Camera





If this is your first time taking off the gear box, take a digital picture of the gear box area.


Step 2

You will need to place your scooter off the ground.

Use a bench or a 4” x 4” block of wood.





Step 3


Loosen the Long Belt Tension Screw under the deck. This will allow the remove the rear wheel off easier. DO NOT remove the Tension Screw.



Step 4


Take off the rear wheel nut. Use (2) 17mm Wrench.




Now slide out the rear wheel bolt. When you slide off the bolt, be careful. There are 2 spacers. 1 long spacer on the right and 1 short spacer on the left.


Line up all your parts.




Step 5


Use a 5mm Allen Wrench and a 10mm Open End Wrench and take off the 3 lower screws that holds the side plate. Remember to line up your parts.








Step 6


Take off the 2 top screws. There is 1 short top screw and 1 long screw




Now take off the side plate and line it up.



 Step 7


When you take off the side plate, it should look like the picture below.



Now take off the 2 engine bolts with spacer.



There are 3 spacers. 1 was where you took off the long bolt.




Step 8


When you take off the screws and the spacers, the gear box will come off. Take off the broken piece of the clutch drum and the long belt. You will see the remaining broken piece of the clutch drum still on the gear box.



Use a 6mm Allen Wrench and pliers. Unscrew the Broken piece. If the 6mm Allen Wrench side screw starts to loosen, don’t worry. Do not take off the 6mm Allen Screw. Just loosen it half way.




Step 9


If the 6mm side Allen Screw loosens, Use a 7/16” Open End Wrench and pliers to take off the broken piece of the drum.



Step 10


Now replace the broken one with a new Drum. When installing a new Clutch Drum, use the 6mm Allen Wrench and your hand. Screw on the Clutch Drum snug.



Step 11


Make sure the Clutch Drum Center Screw does NOT stick put too much.



Make sure the Clutch Drum Screw dos NOT stick in too much.



It should be like the picture below. About 1 to 2 threads in.




Step 12


Now that the Clutch Drum Center Screw is set, tighten the Clutch Drum tight.

Use the 6mm Allen Wrench and your hand.




Step 13


Before you mount the gear box back on, make sure the cable and the tension arm is in the right place.



Step 14


Now put the long belt onto the gear box sprocket.

Now put the gear box back on with the 2 engine bolts and spacers.  Look back at STEP 8.

Keep the 2 engine bolts loose. Now put the Side Plate back on. Look back at STEP 6. There are 2 washers for the lower mount screws. It is the washer on the nut side. Do not use the 2 washers.

Now put the 2 top screws in. Use the 2 washers from the step above. And mount it as a spacer like the picture below.



Step 15


Now that the gear box is mounted on, tighten all 7 screws.



Make sure the Long Belt is on top of the Idler.


 Step 16


Now put the rear wheel back on. Remember the short spacer is on the disc side.



The long spacer is on the belt side.



Do not worry about the belt. Now your spacers are set. Now slide in the long bolt.


Step 17


Now slide the belt on.




After you put on the belt, tighten the rear axle nut.

Adjust your belt tension screw. Adjust the belt so you could push down 1 cog.



Now put your rear mud guard on. Start your scooter. Give it some throttle. Shift from 1st to 2nd. Double check you belt tension. Now you are ready to ride.