Because a few folks have had an issue where their Majesty would not rev above 4500rpm (see http://majestyusa.com/forums/viewtopic.php?t=5189
My bike is a 2006. This should apply at least to years 2005 - 2007.
Make sure you have:
- a flashlight
- a decent allen wrench set (metric)
- a couple magnetic phillips head screwdrivers
- adjustable pliers
- a few plastic pop rivets from Yamaha
- a ziploc bag for all the screws, bolts, and rivets
- a good friend
- some cold beer for that good friend
- a majesty maintenance manual
- a digital camera
, buy a maintenance manual from Yamaha *or* ask your 12 year old nephew to get one from the internet. Don't ask how, he will just know. The diagrams will come in handy.
, disassembly. The throttle body is buried under many many plastic pieces. The engineers had a good sense of spatial awareness (or just a good sense of humour). To get to your target you first must remove or loosen the following:
Passenger Seat and Side Covers
Rider Seat and Storage Box
Air Filter Cases
Throttle Body and Fuel Injector
Don't be intimidated, it's not that bad. See my pics:
The rear cover may seem tricky at first. It is fastened by two black plastic pop rivets accessed from inside the storage box. Yes, you will probably break some pop rivets while removing them. That is why you have a few spares. Take photos to help remember which bolt goes where.
The Japanese factory workers used 22 ft pounds of torque to install bolts. If you have taken your Majesty to the dealer for any reason, they will have reinstalled any bolts with approximately 450 ft pounds of torque. This is why you have adjustable pliers like the red one shown in the photo. Use it to grip the end of an allen wrench for leverage. It really helps. And it works better than the adjustable wrench that we tried first.
The air filter covers and throttle body do NOT need to be completely removed. Remember, your goal is simply to replace a rubber diaphragm thingy.
On the throttle body, carefully remove the vacuum chamber cover because 1) there is a big spring in there and 2) you do not want to get dirt, grit, and grime in the engine. Take a few seconds to brush or wipe off accumulated dirt first.
Do not be shocked at how good the old diaphragm looks. It's been sitting in a sealed chamber for most of its life. Notice in the last photo that there are hairline rips around the edge of the inner ring. After disassembling my bike I was very happy to see those rips!
, test. Keep everything clear of the rear tire and start your Majesty after reattaching the throttle body and air filter cases. Rev it past 4500rpm. Good? If not, then check any cables, screws, and bolts that you may have removed. Best not to wait until you have reassembled everything. Stop the rear tire with the handbrake.
, reinstallation. Reinstalling parts should go more quickly than the disassembly, as you are now familiar with the internal workings of your ride. Make sure you have secured electrical cables and plugged them back in. Some side panels take a few minutes of patience to correctly line them up. What's your hurry, anyways?
, take your bike for a test ride. Prove it on the road.
, wash your bike. It has grimy hand prints on it.
, buy your buddy some pizza for the invaluable help.