My Banshee is beginning to blow oil out the silencers and I figure that it is time for a top end overhaul. I intend to do the job myself. I have done alot of wrenching in the past but this will be the first time that I redo the top end on an ATV. I have the repair manual to follow for specs. I just wanted to get some practical input from someone who has been there. Are there any tricks that will make the job go smoother or is it a pretty much straight forward job? Any input is appreciated.

 

First chk compression....you might save yourself some $$...Ive done my topend on mine ,it was easy just take your time and always work in a clean area..Good Luck..comp. should be 125 ish..thats if its stock...

 

A little tip:

Use some Foamy Engine Brite and thoroughly wash the engine and surrounding area before starting the disassy. You'll want to be very **** about insuring that everything is spotlessly clean during the re-assy. process. Use a die and chase the threads of the head and base studs. Put anti-sieze in the cylinder base stud holes, this makes is much easier to remove again in the future, and helps prevent corrosion. I have done an engine that required welding on the cylinder to repair the corrosion eaten area in the base studs holes.

Use a quality torque wrench and torque to manu. spec's, a "little more" isn't always better, stick with the factory numbers.

It's a good time to replace your reeds as well. They are a consumable item after time. They open and close as often as the crank rotates (133 times a second at 8000 RPM).

Clean and service your air filter, and install new plugs to start it up. Install at least one size larger main jet, my preference is two, we want this thing to run cool and easy. Break-in your new engine gently. Start it and blip the throttle gently for about 5 minutes, shut off, and let cool completely. Do this 4 times, each time retorquing everything. Then ride 4 or 5 times, about 7 to 10 mins, not going over 1/2 throttle but varying the throttle positions. Retorque. Ride another 4 or 5 times, about 12 to 15 mins, not going over 3/4 throttle, again varying throttle position. Now you can ride, and check your jetting. Adjust as necessary. Then ride with occasional ventures into full throttle, keep doing this until you have gone thru a tank of gas.

 

I would definately follow backcountry's advice. I too have built several Banshee's. The key is cleanliness, clean everything like you were in an operating room. This is how I do an assembly. For a topend it is not that big of a job. Tape down several peices of masking paper on a bench, this ensures a clean surface. Then lay down all of the parts in a somewhat organized manner so you can get at them when you need them. Then lay out all your wrenches and sockets, so you don't have to thrash around looking for the tools. I try to put a motor together without any distractions such as radio, other people ect. I just feel like I can be totally focused on the task. And just follow the manual. Do not try to take shortcuts, when it says to torque the cylinder base nuts in a criss cross pattern, do it. There is a reason for it. Good luck.
eric

 

Anouther good tip is: When you get the topend off, it is a good idea to put a rag over holes to keep any debris from falling into the bottom half of your engine. Cuz Banshee Cranks are NOT cheap.