Cannondale Rebuild

Intent: This is not a complete guide, but just a few tips that you won't find in the manuals. You should start by getting the engine manual, which is quite thorough. Read through it, and you'll have a good idea what will be involved. It starts with the motor sitting on a bench, so we will start with the motor in the bike; that's where mine was when the problem arose. Parts and services were provided by Dave, known as 'Canniboomer' on the Cannondaler website. You can email Dave directly at pacrimdm at msn.com, just insert the @ symbol where I put 'at'. I'm avoiding getting Dave on a million bogus spam lists, that's why there is no direct link. Dave will fix you up with lighting fast service and great prices!

Another great resource is Cannondaler. Check out WWW.Cannondaler.Com and go to the forums. It's the most civil forum I've ever had the pleasure of being a part of, and there is a wealth of information to be had for the time it takes to do a search. Note too, that all of the Cannondale manuals are available there free for the downloading. Good stuff!

To start, you'll need to suspend the bike somehow. I use ratchet straps from the ceiling of my shop, you'll have to work out something. The problem is that you will be pulling out the swingarm pivot bolt, it doubles as the rear motor mount, so you have to hold up the back end of the bike at least. Here's how I did it; as usual, click on a picture for a large image. Each larger image opens it's own window, so close the image window when done looking.

Note that you can get the bike hung up, then pull off the skid plate and one of the lower frame rails. This makes room for a jack, and you can support the motor while you remove the other frame rail. When you get to that point, you can start disconnecting stuff. Be sure that you loosen the clamp for the boot from the throttle body to the air box, or you can put excessive strain on it and tear the boot or break the air box. Lowering the jack a little will allow the motor to tip down in the front, and that helps in finding all the gadgets and connections that need attention. Most of the electrical connections are labeled, if you find one that isn't, put some tape on it and write down where it goes on the tape with a sharpie. My advice is to get a digital camera and have an assistant take Lot's of pictures; you can refer to them later when putting it back together.

The swing arm bolt will not want to come out. Drive it out with a big hammer and a large phillips head screwdriver, or any long enough tool that won't slip off and tear up the threads on the bolt. With the swing arm bolt out, the motor is free in the chassis, so keep control of it. You'll want to gently and slowly lower it, checking to see what all is still connected. Soon you've got it out, and things are looking up!

In the left picture, the two hoses connect to fittings in the frame. The large wire from the black cover is from the stator, and it plugs into a unique connection on the wiring harness. From the right picture you can see the shift lever on the right side of the motor. The ATV jack is really handy for this kind of thing; got it at 'Schucks' for $50. In these pix I have the water pump cover off, you can see it on the ground in the right picture.

So now you have your motor out; put it on your workbench and it's manual time!

On the left, the motor with the big cover off and the clutch pack out. On the right, the clutch basket is out as well. Note the Stage 8 kit on all the mounting bolts for the crankshaft and transmission cassette plates. This kit costs a little under $100, and absolutely guarantee's that the bolts will not back out. If you locktite them properly at assembly time, you don't need the stage 8 kit. I like the security it offers. Some of the guys had bolts back out, and it isn't pretty. You start trading motor and tranny oil, and the bolts start hitting moving parts like the clutch basket. It's a bad thing.

Here we have a before and after set: On the left, the stock (on some Cannondales) clutch basket bushing. On the right, the newer upgrade to needle bearings. A machinist removes the brass bushing and then cuts and hones the hole for the needle bearings. Dave can get this done for $40 plus bearings; it's well worth while! Quiet and smooth are good things in a motor!

It's bearing time! If you go in this far to do a rod kit or whatever, do the mains as well. They are about $40 each, and you do NOT want to have to go back in to replace them in a few months!! On the left, the main in the engine case. Note that it is in a 'blind' hole; you can't push it through, and you can't get a nice bearing sized tool on it and use the press. I was really worried about this one, but it was easy. Use a good pin punch, about 1/4", and you'll try to drive the rollers first. This won't work, but it will pop out a roller or two and screw up the race (plastic) enough that you can pull it out. With all that stuff out of the way, use the pin punch and a large hammer to tap on one side and then the other. The angle is pretty bad, but the bearing comes right out. The picture on the right is how I removed the inner race from the crankshaft. Frankly, if you don't have a puller like that, I don't know how you will get this one off. I've heard that you can use a dremel tool with a cutting wheel and split the bearing, but I had the puller so I went that way. The bearing is on there pretty darn tight, so be patient. Putting the new one on is easy; heat it up good and have your drivers all laid out. Slip the hot race on the crankshaft and wail on it. Mine was on with about 5 hits, the faster you go the faster it goes. Stopping for any reason gives the bearing time to cool, and it gets tighter by the second. I was leery of pounding on the crank any more than I had to: they are pressed together, you don't want to beat it a few thousandths out of alignment!

Gee Whiz stuff. On the left, the new Wiseco piston and new stock sleeve. The manual says to use a fancy fitting to install the sleeve. I used a plastic faced mallet, tap firmly on this side and then that side and she goes right in. On the left, the cylinder head after decarboning. Oooooh, Aaahhh. Whatever...

More pointless pix, unless you really like geeky motor stuff like I do. Far piston is from an '87 KTM 500cc two stroke, something like 65 horsepower. Left piston is from an '87 Husqvarna 510 4-stroke, about 50 HP. Center piston is the early Cannondale piston from 2000, Right piston is the one out of my bike, 2002 'dale 440, about 40 - 45 HP. I went with the earlier piston because they are higher compression (12.5 to 1, up from 11.8 to 1) and they are cheaper. I don't rev my bikes much, so a higher compression motor will fit my style. (More bark, especially at lower RPMs, but less rev-out).

This is where your oil goes; at the front of the motor you will see a large slot, leading down to parts unknown. Well, this is where it goes. If you drop a piston circlip (don't ask!), this is where it will be found as well. Note the shape of the case follows the throw of the crank pretty closely, acting as a 'windage tray', for those of you familiar with such things. Oil from the crank and such gets stuffed down into here, where the scavenging pump sucks it up through the screen in the right picture and pumps it up into the frame. To leave all this on, use a large phillips head screwdriver when you install the circlips for the piston; stick it all the way through the wrist pin, and out far enough that the circlip is around it before you start into the motor with it. If the clip pops off the pliers, it's stuck on the screwdriver shaft and can't jet down into the motor. Another tip; use dedicated circlip pliers, or make some out of a pair of needle nose pliers. I used the universal kind of circlip pliers, and they work fine. At least, up until you are less than an inch from the groove in the piston. That's when the blocky section of the universal pliers runs in to the edges of the hole in the case you have to reach through; You can't move in, you look at the interference, you loose focus and 'pling'! It's gone!! Grrr. So now you know, no excuses! Use the right pliers and it'll go in the first time. Use the screwdriver and even if it comes loose, it doesn't go down into the motor.

On the left, you see my valve cover. The bike came with conventional coolant, which attacks the magnesium valve cover with a vengeance. During the first maintenance I did on the bike, I used a dremel with a tiny brush and removed almost all of the corrosion. Then I got out the trusty 'JB weld' and covered the pitted area's. Finally I switched to 'Evans' waterless coolant. It's non conductive, and stops galvanic corrosion completely. Other than the disgusting brown color, everything is as I left it more than a year ago. There are other important advantages to the Evans coolant, but this isn't where I want to discuss it. It's worth the $25 per gallon, easily.

On the right is a bit of fuel line. All the lines looked great when I tore the bike down, but when I started to reinstall stuff, I noticed that ALL the fuel lines would crack as soon as you flexed them. This is a big deal: remember, 'dales are fuel injected! That means that a broken fuel line released gasoline at 40 PSI; a very bad thing. Your local auto parts store has fuel injection line, about $4 per foot, and you can replace all of it with 2 feet.

Left: look at the beating the skid plate takes from the motor case! I'm thinking this has got to make noise and cause vibration. I used a couple of pieces of a serpentine belt as pads between the motor and the skid plate. I've got plenty more if anyone needs some! You tighten the front mounting bolts, then slip the belt bits inbetween the skid plate and the motor, then insert and tighten the rear mounting bolts. It's tight, and there won't be any vibration or clanging! On the right, $50 on ebay makes those winter evenings in the shop quite comfortable. That reminds me, I've got to get that spare bottle refilled!

Final tip: Put your battery on the charger when you start this project. I waited a couple of weeks for my crank, then had to find the time to put things back together. When all done, I left the spark plug out and cranked it over for a minute or two to get oil circulating before it fired up. Then I installed the spark plug and hit the green button in earnest. It blew a ball of fire out of the exhast and started the wrrr- wrrr rr- w rr rr r thing. Dang it!! It would have started right up if the battery was charged up. A few hours later after a nice recharge, that's just what happened. 8^)