New Member. New Rider. New Bike Owner. Old KZ650

Ok. So I have wanted to get a motorcycle for some time now. Earlier this spring my wife finally broke down and said I could get a bike. I've never ridden a motorcycle before, but I am very excited about this new adventure.

I will be picking up my new (to me) 1978 KZ650 this weekend, but figured I would get a head start on the process of bringing her back to life. It currently does not run, and these are the issues that I am currently aware of: dead battery, bad starter, high compression. Are these issues pretty easily fixed? My pops has experience working on motorcycles but i want to try doing this on my own for the most part....only calling him in to help when I am in a tough spot.

My full intention is to turn this bike into a cafe style bike. Any ideas as to the best place to start or point me to another thread where someone has taken a poorly treated bike and made it into a finely tuned machine and has well documented the whole process!

Glad to be here and I really hope to learn a lot from the wealth of knowledge I know you guys already have!!

Welcome to the madhouse :silly:

If you're new to riding, do your wife a service and get some education before you take to the road. I'm sure she prefer to keep you safe and sound

What do you mean by high compression? Has somebody tuned the engine to the hilt? If the engine is stock and hard to turn over, you either have something mechanically wrong or fluid in the cylinders.

I am definitely planning on taking a course on rider safety and the basics of how to ride. That's not just for my wife's peace of mind, but for my own as well.

In regards to the compression question, that is just what the previous owner told me. I will look into the fluid in the cylinders once I get the bike. Would you reccomending taking the motor off and apart and then doing a complete rebuild?

Not having seen the bike, this is what I'd likely do:

Determine when it last ran reliably. If carbs hold fuel and it's not been running for the past year, expect to remove and clean carbs. But you could try to run some Seafoam through them first, although I'd strip them.

Remove spark plugs and kick engine over. There should be no mechanical sounds and resistance should be low as there is no compression to overcome. If fluid comes out the plug holes, determine what it is (oil/fuel/water). If it is water, definitely open engine. Chances are it's toast, though.

Do a compression test - less than 7 kg is really bad, but if the engine has sat for a long period piston rings can be mildly stuck. This may rectify itself with some use. Compression may raise as a result. More than 12 kg and you should find out why.

Do not omit checking valve clearances (as I did) - you want the valves to have sufficient clearance.

Check how the spark plugs look. You can find plenty of sites with explanations and pictures to guide you if needed. Smell them if moist. Replace if worn.

Set timing statically after gapping the points to 0.35mm and checking that their surfaces are not burned or pitted. Slight pitting can be sandes smooth, just make sure the points are sitting square against each other. If badly pitted, replace points and condencers.

Cam chain tensioner should be automatic on your '78, so no maintenance should be needed there.

Drain the old oil cold. If engine has sat for years with dirty old oil in it, I would fill it with 2 litres of the cheapest oil you can find plus one litre of ATF (automatic transmission oil) and run it warm with about 2000-3500 rpm. 10 minutes should do. Drain oil and now remove oil filter. Fit a new filter and fill up with 3.5 litres of fresh motorcycle oil.

I'd also fit new tyres AND tubes if they are more than a couple of years old. Check the rear brake linings and drum.

The front brake, if you plant to keep it, should have its caliper checked for free movement (along pins plus piston) and flushed with fresh fluid as a minimum.

Check the fork for leaks and replace the oil with fresh 10W or 15W fork oil.

Check steering stem bearings for freeplay (none) and smooth action with nigh on zero friction.

Check the swingarm for freeplay (should be none) and smooth operation.

Check that all cables and levers etc. are lubed and move smoothly.

Check chain and sprockets for wear and make sure the rear wheel is tracking straight.

There are probably more that should be done, but this should keep you occupied for a couple of hours :lol:

Wow. Looks like I've got a bit of work cut out for me! I know that the bike was running as of last year so hopefully there isn't anything major wrong. But you just never know..Thanks for all the help faffi! I will let you know what I find.

Welcome Rory.

The Do The Ton site is a Cafe forum for all types of bikes.
Good insperation can be found there: Do the Ton.

Search for Cafe here, and on the KZ650.info forum.


Get yourself a service manual, the Kawasaki SM being the best, and go through all the periodic maintenance items.

No offense, but if you take the motor out and take it apart you are asking for big trouble. Taking it apart doesn't cost a dime, but putting it back together is not free. I'm not sure why some folks feel compelled to do this as a first step, but more often than not if they do the bike never runs again. I don't know anyone who would do that to a car before at least seeing if the engine can be started. You don't need to do what one member did as his Step 1 (see pic below). I don't believe we have heard back from him since he took that giant step.

Here's my opinion on the engine:

Step 1. Buy a Kawasaki Service Manual for your specific year/model; eBay normally has them.

I'm assuming the previous owner hasn't run the engine in years.

Step 2. Spritz a bit of oil through the spark plug holes and let it sit overnight.
Step 3. Using the kicker - GENTLY see if the engine is frozen or free. Push on the kicker just a little to see if the pistons will move - you don't need to rotate the engine a bunch; you just want to see if the pistons will move at all.
Step 4. Assuming the engine is not frozen; change the oil and filter. If the engine is frozen you will need to find out why.
Step 5. Again, assuming the engine has not run in years - remove the cam cover and put some oil on the cams and anything else in the top end.
Step 6. Clean the carbs
Step 7. Flush the fuel tank of old gas, clean rust if rusty, and refill with fresh fuel.
Step 8. Install an inline fuel filter. Install new CORRECT spark plugs.
Step 9. Ensure the air filter is not clogged up with dead mice, rags, or other stuff that should not be there.
Step 10. Buy, PROPERLY charge, and install a new battery.
Step 11. See if it will start (choke on, key on, fuel on, tranny in neutral, clutch lever pulled in, hand away from throttle).
Step 12. If it starts don't stand there and rev it up. Let it warm up for a few minutes then shut it off. Before you even think about riding it you will need to check all the safety items - especially the tire, brakes, and anything else that can get you killed if they don't work well.

Good luck. Ed

BTW, there's no such thing as an "old" KZ650. There only are nice ones and those that need TLC.

Ed,

Good call on not disassembling the engine! it would be just like me to lose one tiny screw that is very important and have the engine never run. I've been told the bike ran as recent as last year. I will take your steps starting with number 1 and get myself a service manual. That seems to be the most common advice i've gotten so far so that is where I will start! I sure hope I can get this puppy up and running! I keep looking through these forums seeing everyones bikes and the things they are doing/have done and I am getting so excited!

Again, Thanks to everyone who is giving me advice...I NEED IT!!