Barn find.... bottom to top

[JDT]

Ok so time to get to the meat and potatoes. The Drive.

Chaincase. Chances are when you pull the cover off you will find either black tar that 40 years ago was liquid or you will find nothing. But as long as the cover is off and suspension is out, remove the two bolts that retain the sprockets. Pull the two spockets and chain off at the same time and let them soak in solvent. A coffee can with kerosene, a parts washer or whatever you have. After they are clean examine them for worn or broken teeth. Check the chain over real close for wear, bent or damaged links. Most of the time brand new parts are available. Now grab some sockets and take out the 6 bolts that hold the drive shaft bearing flanges in place on the tunnel and the speedo drive. Lossen the bearing reatiners on the drive shaft. Slide the drive shaft to one side and drop the track off the shaft. Then pull the drive shaft out of the chassis. New bearings cost $15 each. Buy them! Inspect the drive sprockets carefully. Look for cracks, excessive wear on the teeth. Look for signs that the sprockets have shifted on the shaft. Check the splines on the shaft and the bushing for the speedo drive. And the square drive key. Having fun yet?

Jack shaft. Simple hand tools will go a long way when working on a sled, any sled, any color, any age. Grab one of the two sheaves on the clutch and give it a wiggle. If it wiggles you have more work. Probably needs new bushings. Remove the secondary clutch from the shaft, usually just one bolt. Set it aside for later. Look at the keyway on the shaft and the key itself. A new key cost 50 cents so if in dought, through it out. Now grab the shaft in the middle when it is still mounted in the sled. If you can move it at all up or down or side to side you have more bearings to buy. Zero movement is the spec here. Grab the brake disc. Wiggle it. Here there should be play. The disc has to be able to move side to side (or float) on the shaft otherwise the brake pads will wear prematurely. Look at the pads. How much material is left on them and is the wear even? Are there groves worn in the disc? Are the calipers loose? Any missing hardwear? If any part of the brakes need service than remove the whole assy.

Secondary Clutch. While the clutch is very simple in design and easy to service it's proper operation is critial to overall performance. There are many different clutches out there but they all operate on the same principle. First thing to do is take it appart. Caution is needed here as the assembly is under spring tension. Also note that clutches are balanced at the factory so you should mark the two sheaves and the ramp so you can reassemble in the same position. Either bolts or pins hold it together. Keep pressure on the assy as you lossen or remove the retainers so the spring does not lauch them into your face. A vise, a buddy or a specific clutch holder will do the trick here. Ok so now you have about 8 pieces laying the work bench. Clean everything first then inspect. Sheaves need to be groove free and smooth. The ramps may show wear but should be even. The slides, cams, buttons or shoes are only a buck apiece so replace at will. The spring tangs may be broken or cracked. The spring should look straight. If the coils are deformed replace it. Closely examine the two holes that the tangs fit in. Look for fractures. Clutch parts are made from diecast metal so do not confuse casting flaws with cracks. Some high perforemance, ie racing componets are made from aluminum and spin at 12 grand. These clutches are best left in the hands of professional rebuilders as balance is critical at those rpms. They can also do ultasonic examining for metal fatigue. Are new bushings needed? Lube the shaft, bushings and ramps on reassembly. The spring usualy goes in the middle hole but not all clutches have 5 holes. Some only have one. Proper preload of the ramp is very important. Consult the service manual for you specific sled.

Primary Clutch. How do you get it off the engine? This is one place where the proper tool is warrented. There are probably 30 different clutch pullers out there for as many different clutches. If you only intend to work on a couple of different ones than buy the right tool for the job. Diecast metal is no place to use a torch. Same goes for a 3-jaw puller. Otherwise borrow one from a sled shop or tote your engine to their door and have them pop it off for you. Either way a little prep work will make removal easy. Remove the retaining bolt, washer , locknut, spacer and lay the engine on its side. Spray your favorite penitrating oil in the hole. Let it sit there at least overnight. Most all clutches are friction fit on a tapered shaft so if it has not been off in 40 years it will be stuck real good. Some really old makes actually had threaded on clutches. Once it is off it needs to be disassmebled. Again it is under spring pressure so use caution. Unlike the secondary, the primary can have a lot more parts. Maybe as many as 40 pieces. It is not nessecary to completely rip it apart but you do have to open it to check for wear and luberication. If you have to replace some of the smaller pieces than set out your parts tray. There are cams, arms, spacers, rollers, pins bolts, ramps, splines, bushings, ect. Did I say only 40? Some clutches actually have a bearing for the belt to ride on at idle. Anyway the key here is wear. Once all the parts are clean, with your eyes and your fingers you can inspect every part and the bad ones will be obvious. You will be able to see wear, cracks or things that don't move that should. Lubricate parts that need to stay free. Reassemble.

Controls and Insturmentation. Things like brake and throttle levers, switches, buttons, levers and knobs should all be checked for smooth operation. Ignition keys should lock the key in the switch in in any postion except off. If you have ES, the spring return should snap the key back to RUN on it's own. If you did not get a key with your sled, brand new switch assy with two keys are still made for just about any sled for less than $20.00. Look at the cables for frayed wires, kinked housings or rust. If it is not free moving replace it. Check plastic levers for cracks and wear where the pins attach it to the blocks on the handlebars. Choke levers or knobs should move freely. Check for proper operation of primer buttons or knobs. Check gauges for cracked lens and proper mounting in the dash. Test dimmer switches with an ohm meter or continuty tester before you even start the engine so you know they work and wont become a pain in troubleshooting electrical issues later. Same goes for throttle safety curcuits. These can get very complex on newer models with as many as three on the handlebars and three on the carbs with a triple under the hood. Test light bulbs on the dash gauge back lights. It is easier to do it now then after all the airboxes and outhr parts are installed on the sled. Any other electrics can be checked before reassembly also. Things like high beam indicators, low oil lights, warmers ect.

More later, too many typos.

[dap574]

webman should include this and more of your wisdom as a first page of all vintage sled manuals!! very good! Thanks Dave