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Much has been written over the years about Cushman's downfall due to the two speed transmission, especially when imports came in with three and four speeds. Cushman Eagles were unique because they looked like a small motor cycle,

had they invested in a good tranny they would still be in business. I have a 50's restored barrel spring, just couldn't hack the two speed. The Reiss trany at $1200.00 was out out of my budget. Answer..... I went to a local salvage yard and found a scrap cycle with a five speed, a Yamaha Enduro 100 with a fully synchronized five speed and oil clutch for .60 cents a pound (25.00).

 Here's the process: Remove the jug from the Endura, take the two halves apart and remove the piston and crank. Replace the crank with a straight shaft with drive gear installed on inner end and sprocket on outer end. fabricate a flat piece to cover the hole where the jug was. Then fabricate mounts for trans to frame. If you are modifying a Cushman Husky you will have to use a jack shaft to transfer drive to left side of transmission. All parts to do this conversion are available at McMaster-Carr.com. I modified the foot shifter to use with the Cushman tank shifter so it would look original. The Yamaha Enduro 100 is a nice small unit and works great. I now have the sweetest riding Cushman around, what a joy to ride!. If anyone is interested, I can supply details and pictures. I estimate the job took about 20 hours.

John Lojewski, mandjlow@yahoo.com   1/16/2011

Bill Bruce was trying to work the side plate with the neoprene seal in it over the crankshaft on a Cast Iron Cushman engine. He found it very difficult to work the seal onto the larger diameter area it seats on without damaging the seal and he suggested the possibility of making some kind of fixture to facilitate the job. With that inspiration, I made a thin bushing, tapered on one end, square on the other, that can be slipped into the neoprene seal. Using this bushing one can simply slide the side plate onto the engine and the seal drops right in place with no effort and no damage.
Jim Frederick

When installing new valve guides, if you do not have the correct arbor use a 5/16 bolt that is long enough to index down in the valve guide bosses below the oil chamber to help center the assembly while pressing or driving the guide in. Ed note: Check the expansion/contraction method below to make this job even easier.

There were at least three different style oil pumps used in the two piece Cushman engines. The first was used with crankshaft 82-5 and 86-5 (Varimatic drive) and has a curled circle at the end of the delivery tube. The second has a delivery tube that is slightly curved. Both of these pumps have the second spring and ball in a vertical configuration. The third pump has the second spring and ball at a right angle. The first model must be used only with the older 82 series crankshafts, the second and third are fine for the later 92-5 crankshaft. 
Cushman engineering bulletin dated January 8, 1952.

Here is how to get the 3/8" adjustment on cast iron super Eagle clutch accomplished. Remove the aluminum cover and tape a 3/8" stack of washers where the cover touches the throw out bearing. Use an "X" of electrical tape to hold them and it will not change the thickness. You can then install the cover and push it in with your hand until you feel it contact the bearing...no more guessing. 
Dave Davenport 

I learned one little Mikuni trick that helped increase the power in my scooter a lot. When I got to playing around with the Metering Rod I had to remove that little round brass washer. The washer has a tang on it that I always inserted upright. Unfortunately that let the Metering Rod move up and caused inconsistent performance. Putting the tang down into the hole improved the performance dramatically.
Jerry Jernigan

Here is a a method for installing the Timken bearings on Cushman crankshaft. Put a
little motor oil on the new Bearing then set it on a 40 watt light bulb.
While the bearing is heating make sure that there are no burrs on the crank
shaft bearing surface. Put the crank is in the vise horizontally. When the oil on
the bearing on the light starts to smoke take the bearing in a gloved hand and
quickly slip it on the crank. Now this can be tricky; if the bearing is not
started straight it will stick and not go on. If it sticks gently tap it off of the crank
and reheat it. Then try again. After you do a few of them it becomes second
nature. One note, once the bearing starts on correctly do not hesitate but slip
it home. The bearing will cool very quickly once it touches the crank and
will shrink. Do not heat the bearing with an open flame it will be ruined. The bearing can also
be heated in oil but that is a very messy.
Richard Smith

Placing the bearing to be installed on the shaft in a regulated oven preheated to 350 degrees will insure that the bearing is hot enough, but not hot enough to damage the grease. Additionally, the shaft can be cooled with dry ice or even a freezer to reduce its size and make putting the bearing on easier.
Forrest Buerer

Remember that in the above two suggestions above, we are talking about installing a press-fit bearing over a shaft. Remember that cooling shrinks the item and heat expands its size. So in the above suggestions where the bearing is being placed over the shaft the bearing is heated to increase its size and (optionally) the shaft can be cooled to reduce its size.  If you are installing a press-fit bearing into a cavity then the heating/cooling is reversed:  The bearing is cooled and the cavity is heated.
Jim Frederick

I discovered a versatile and feature packed electronic speedometer that will work on a Cushman.  It uses a magnet and sensor pickup and it calculates KPH or MPH. The model for the Honda trail bike is the most universal and should fit your Cushman quite well. Check out the unit at http://www.trailtech.net
John Mastbrook

If you have a leak around the high speed needle in your Tillotson carburetor this tip will help. Purchase one of the cheap imported fuel filters, part number 814753 in Carpenter's catalog. Remove the neoprene packing from around the fuel cut off needle and use it in your carburetor in place of the old leather packing. You leak problems will be over. Someone out there may know where to get just the neoprent packing, but I have not been able to find it. 
Tom Collins

An easy way to install valve seats and main bearing races. Place seats or races on dry ice for two to three minutes while using a propane torch to warm up the casting.  Then using the appropriate bushing driver lightly tap the seats or races into position.
Ed note:  Don't overlook expansion/contraction for any press fit bearing or bushing. If you have not  tried this method you will be amazed at how well it works. A heat gun works well to expand small items. A freezer can also be used to cool and shrink, but dry ice is will take your part to a much lower  temperature if you can find it.
Ralph Birkenfeld

To start my flathead Eagle easily I reach down and turn the engine back (farther away from the start of compression) with the clutch until it stops, then kick it. It starts spinning easily, and the Inertia of the flywheel  helps carry it through the compression stroke. It starts easy with no compression release. Delmar Baker

If you are placing a Mikuni 22mm carburetor ("Stage One" ) on a normal 8 horse motor that is neither over bored nor has huge valves installed, I would suggest a 25 pilot jet and a 145 main jet. Set the needle clip in the second from the bottom notch. Set the air screw at one-half turn open. The pilot jet controls gas flow at idle to 1/4 throttle, after that the needle jet takes the gas flow up to about 3/4 throttle and then the gives it to the main jet the rest of the way to wide open. The air bleed screw controls the amount of air that is mixed with a constant flow of gas that flows through the pilot jet. Screw it in to lessen the air flow, out to increase air flow. If it starts OK blip the throttle and if it hesitates then turn the screw in slightly, if it blubbers turn it out a bit. Eventually you will find the correct position.  (extreme altitudes may require a different clip position)
Carl Redmon from Cushmannet

Want a little more power from your Briggs Vanguard Engine? One easy way to make your motor run a little stronger to be compatible with high RPM's is to advance the timing about 10 degrees. How do you do  that?  Easy, the same way Cushman did on the Silver Eagle engine. Cut away the left half of the flywheel key down to the level of the shaft. This will allow the flywheel to rotate an additional 10 degrees. Hold it there while you retighten the flywheel nut to 125 Ft/Lbs. You must have both a flywheel puller and a strap wrench to hold the flywheel while removing and reinstalling the nut. You will notice your motor starting easier and running less like a stationary motor.
Carl Redmon from Cushmannet
Ed Note: Drops a full second off the 0-50 MPH time in a 16 hp Vanguard. For 10 degrees mill off .100. The keyway is about .238 inch wide total so 1/2 (.119 inch) equals about 12 degrees, still OK. It does make it start easier, too.

If you want to be noticed more by fellow drivers and help prevent someone from turning in front of you try the headlight modulator made by Signal Dynamics. It blinks your headlight four times per second (daytime only) and really gets attention. I have been using on for 2600 miles and I have even had a couple cars pull completely off the road thinking I was an emergency vehicle. It is completely legal in all 48 states because the U.S. DOT provides for it in their regulations.  It is available at any motorcycle aftermarket dealer. It will only work with a DC system using a battery.
Jim Frederick

Regarding Mikuni Carburetors, there is a 92 page booklet entitled Sudco Mikuni Tuning Manual, part number 002-999, available by calling sudco International at (213) 728-5407. Price is around $10.00 to $15.00. Has full information on all Mikuni carbs included exploded diagrams, part numbers, tuning instructions, etc.
Doug Young from Cushmannet

The best spark plug for a Cushman Husky is the Bosch 6200. Had them in mine for some time, never replaced one yet.
Jim Brannon from Cushmannet

Stop leaking gas caps! The majority of leaks are through the vent holes and then out the edge of the cap. Take two plastic electrical butt connectors just slightly larger than the vent holes...bevel the ends of them on a file or the edge of a grinding wheel so you can jam them into the vent holes...seal around them with gas proof epoxy (I used marine-tex available at boat dealers or marine supply stores). Now the cap has dip tubes for vents and the gas can't splash up through them and leak on your nice paint. It works very well on tanks without the splash baffle tubes.
Dave Davenport

On the above Gas Cap Tip you can also use a piece of miniature aluminum or brass tubing from a hobby shop of the correct size to fit in the hole under the cap.  Feedback says this idea works very well, but that only one tube is necessary, just stop up the other hole in the cap. The bottom end of the tubing must always be a little above the level of the gasoline. JB Weld works well and is not affected by gasoline. - Ed

Here is an easy way to seal the side plate and shims on the Cast Iron engine:
I use a light coat of aluminum paint on all gasket surfaces. I paint the shims (both sides), block and the side plate gasket surfaces with aluminum spray paint prior to adjusting the crankshaft endplay. This way the endplay doesn't change when you make the final assembly of your engine. The paint is soft enough to bond together and seal the engine and as an added bonus, it is easy to disassemble when the time comes. Hope this helps.
Ross Murphy from Cushmannet

To get the throttle bushings out of your Tillotson carburetor first use a 1/4 inch tap to cut threads inside the bushing. Then find a bolt to match your tap and run a nut an inch or so up the threads. Put a 3/8 inch thick spacer over the bolt that has an inside diameter a little larger than the bushing.  Screw the bolt into the bushing, then tighten the nut. This will force the bushing out of the carburetor and up into the spacer.
Glen Liddle

Tip for Servicing the Silver Eagle Clutch:  Take a 8 by 10 inch piece of 1/2 inch plywood and cut a 6 inch hole in the center. Nail two strips of 1 x 2 on the edges.  The clutch can be laid back-side down in the hole. This tool will support the six bolts while the clutch is being serviced and the spacer washers will stay in place on the bolts. It will take less time to make this holder than I have spent chasing spacer washers across the shop and trying to hold everything in place while putting on the nuts.
Larry Harding

Here is a way to get a good hard finish on a small painted part. After preparation of the part put on a very light coat of primer; A thick primer will weaken the finish. Next give it a good coat of enamel. Then put it in a 170 degree pre-heated oven for 30-35 minutes. Fumes will be very minimal. A good brand of canned spray paint also works good. This comes out similar to an automobile finish. A variety of supports to hold the item while painting and baking can be fashioned from scrap metal. You are only limited to the size of the oven. I mainly use this process for small detail parts, but it also works good for larger items. 
Michael Estep
Some paints may be soft immediately upon removal from the heat; they will harden quickly as they cool. - Ed
 

Many have asked about obtaining the special tool that is used to set the brake rivets. You can purchase them from Aircraft Tool Supply, 1-800-248-0638. They have two, one that operates with a threaded model, part number W404 at a cost of $22.95 and an impact (hammer) model, part number W403 for $14.95. The threaded model does a perfect rivet job for Cushman brakes for little extra cost. The rivets cost $4.95 for a box of 100.
Jim Brannen

I have tried various ways to make the seat more comfortable on my 1950 Highlander 714. I first bought the standard vinyl seat cover that is lightly padded. The problem is not bumps with this seat, but vibration. I tried adding a one inch thick soft foam insert under the vinyl cover. This addition not only made the seat loose it's comfortable contour, but made it look over stuffed. It did not modify the vibration. So I tried cutting a piece closed cell foam (1/2" thick or a little less) the size of the seat pan and placing it where the soft foam had been. Vibration transmission to my bottom has been reduced significantly with this simple modification. The seat still looks almost as it did before the modification. This closed cell foam can be purchased anywhere that camping pads are sold. Try it you will like it.
Dan Hudson

Installing fasteners in the ends of the early Cushman front fork barrel springs is a real problem because of the need to line up a flat washer, a lock washer and a nut inside the spring at each end and get them to stay in place while threading in the fasteners. It is especially difficult on the the top of the spring since the washers and nut will want to fall to the bottom.   Some method of holding the items in place while threading the special fastener into the nut is necessary.  My solution to this problem is to place the spring on the workbench and drop the two washers and the nut inside the spring in the proper order. Line them up, and without moving anything slip a piece of electricians black tape across the nut and tape it and the washers to the coils of the spring. In a similar manner prepare the other end of the spring with the washers, nut and tape.  Now you can gently pass the bottom perch bolt through one end of the spring, through the two washers, and screw it onto the nut and loosely tighten it. To secure the top side of the spring hold it in place under the frame tab.  Pass the special fastener through the frame tab, into the spring, through the washers and screw it into the nut. Rotate the spring to the desired position and tighten the nuts. (Grinding a 1/2 end wrench thin and removing some of the side wall thickness will allow it to pass into the spring and make tightening the nut very easy. - Ed)  Now you can tighten the nuts fully. Be sure not to twist anything as this will place a stress on the suspension parts.  Dan Hudson

Here is a tip of wisdom in rebuilding the Cushman motors. While the motor is apart on the workbench take a cut strip of 3M grade 2000 wet or dry sandpaper and mirror polish all bushing surfaces. Moisten the paper with WD40, then buff the bushing surfaces like polishing shoes. Also polish the camshaft including the lobes. This process will dramatically lower the friction without measurably wearing the bushings. You will have to lower your idle speed when you start the motor! This process will also increase the life of your motor. David Jameson

I was having trouble with the flexible exhaust tubing clamps being strong enough to crush the flex exhaust tubing sufficiently to seal the exhaust system. Here's what I did to solve  this:  Around the circumference of both ends of the flex tubing make 6 cuts evenly spaced about 1/2 inch deep.  Get some thin aluminum flashing and cut a piece 5.8 inch wide and long enough to make a little more than one wrap around the outside of the flex tubing to cover the six cuts.  Wrap the aluminum over each end of the flex tubing covering the cuts.  Slide the clamps on over the aluminum, slide the exhaust system together and tighten the clamps. The cuts will allow the ends of the flex tubing to be flexible enough to grab the exhaust pope and exhaust manifold, the aluminum flashing seals over the cuts and the extra thickness of the aluminum flashing gives the clamps a little more bite.  It works GREAT! Ronald V. Pappaso 

This week end I lost one of my 1965 Buco Fiberglas saddlebag lids while riding. After a long search I found it, but don't take chances. Add a small safety chain from the lid to the saddle bag to prevent a fly-away in case the latch pops open. I used a small vinyl covered chain from Home Depot. Use washers under the screw head and inside the saddle bag to distribute the stress. Ronald V. Papasso

If you have a cracked engine block see the article on how to repair it

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