Tuning the beast

I have been making some progress getting my old Z1 running well. The bike runs pretty good but I have developed a problem getting it to idle. The bike seems to either idle high or low I cant find the happy medium. That issue is not really the cause of my post. I'm trying to get advice on the order of progression to make sure my bike is running the best it can. I have worked on the carbs, done the wiring upgrade etc, but I cant get it right.

Can anyone give me a step by step or a summary of how to get it running to its full potential. I'm willing to do just about anything even taking it to a mechanic if anyone knows a good one in Indiana.

Thanks in advance.

What's the condition of your intake boots. They boots between the carbs and the motor that is. My bike would scream but just would not idle correctly, usually high. I had cracks on that old rubber and they werent even visable, but when i replaced them the bike idled beautifully.

I replaced the boots earlier today with new ones. The bike runs better but the idle problem is still there. I also adjusted the float height while I had the carbs off.

the best way is to follow wired george, new plugs, check valave clearance, check timing, check timing chain tension, then look at carbs.

The early Z1 carbs require quite a bit of extra work to make them work right. Other than the general tuning advice, it is hard to give specific advice since you didn't mention a specific problem other than the carb issue.

I was looking for a more general step by step process / check list for insuring a bike is running up to its potential. I mentioned the problem to illustrate the fact that I cant get every perfect. I fix one problem and another comes up. I thought it might be better to start from square one and spend a week going through everything fixing and adjusting as I go.

Here is a better description of the current isssue that bugging me right now.

The bike starts and runs OK, but returns to idle very slow at times. For example I will crank the throttle and let it go and it takes 10 - 20 seconds for the bike to return to idle. Sometimes the bike stays at a high idle and other times it goes to a low idle that is just short of dying. The carbs have been cleaned and the floats adjusted. I replaced the old carb boots yesterday and it made a difference, but did not fix the idle problem. The new boots actually made the bike idle faster and backfire a little. I'm not sure what that means.

I was thinking some thing like
Step 1. check compression (fix if needed)
Step 2. etc etc

I'm guessing some of the other not so mechanicaly inclined people like my self would appreciate the direction.

I had the same problem with my KZ1100. While there are several possible causes, what fixed mine was to balance the carbs. (See step-by-step post below, step 12-13 is what fixed my "return to idle" problem.)

Post edited by: NormZ, at: 2007/03/29 15:28

Here's the step-by-step process that I followed with my KZ (previously posted). Search this forum for more detail on each specific item.

1) Check valve clearance and adjust if necessary. Do this first as it could affect your compression. While you have the valve cover off, may want to inspect the cam chain, cam chain idlers & tensioner, and cam chain timing.

2) Once valve clearance is in spec, check engine compression. If compression is bad you have a different set of issues and may want to reconsider if you really want to restore the bike or not. The rest of this procedure assumes that your compression is good.

3) If the starter will not turn the engine over then troubleshoot electrical system. Charge battery and/or replace if it will not hold charge.

4) Check out the ignition system. First make sure you have good strong spark on all cylinders. If voltage at coils is low do wiredgeorge's relay coil feed mod. Install new spark plugs. After getting good spark check ignition timing.

5) If fuel tank is rusty inside, remove and clean it.

6) Check fuel petcock operation. Repair/replace if necessary.

7) Install (or replace) fuel filter. Do this after cleaning the fuel tank and before cleaning the carburator.

Remove carburator, dissamble, clean, replace internal o-rings, reassemble & re-install. When cleaning make sure all jets and passages are clear by blowing air through. Replace carb boots if they are hard or cracked.

9) Check fuel level in carb bowls. Adjust if necessary.

10) Check condition of all vacuum lines and caps. Replace any that are hard and/or cracked. (Engine will NOT run well with a vacuum leak!)

11) Set idle mixture screws at initial position indicated in manual. Start engine! Adjust idle speed screw to correct idle speed, or as low as you can without causing engine to stall.

12) Sync carbs. (Be sure to have a fan blowing on engine, and turn off to let cool occasionally if this process takes more than a few minutes).

13) After syncing carbs, adjust idle mixture screws to achieve top RPM (w/o changing throttle or idle speed screw). Then adjust idle speed screw to achieve correct idle speed.

13) Now the engine should be running pretty well. At this point I would change all fluids (engine oil, brake fluid, fork oil) as well as oil filter and air filter. Also a good idea to lube the clutch and throttle cables. Many people recommend changing fluids as the first step but I waited to see if I could get the engine running or not.

14) Now you can start on the chassis. Personally I would just get on & ride for a month or two before beginning any chassis work. Exception would be tires & brakes...make sure tires are good (10 yr old tires need replaced even if tread is good!) and that brakes work well before your first ride. While riding you will likely find that some problems will fix themselves while others will develop.

15) Eventually consider repairing the following chassis items: Replace front fork seals, replace brake pads, adjust clutch, replace rear shocks, repack wheel, swing arm, and steering head bearings.

16) After all the above then you can begin polishing, painting, upgrading, etc.

Thank you for the list. I will use this and see where I get. Its hard to tear into when weather is warm, but I want to get it running as well as possible. I hope this process will get me there.

I did go for a ride today and inspected the plugs afterward. The pics below look like I might have the mixture a little lean. What do you guys think?




Post edited by: bharper6649, at: 2007/03/29 16:54