Maintenance at 114,307 miles on '88 250 Ninja
Time for a spot of maintenance so I got in a set of oem tires, premium 14 and 42 tooth sprockets and a Tsubaki Omega premium o-ring chain from Dennis Kirk. The latter gave his usual accurate and speedy service.
The same chain was installed on 11-10-04 at 95441 miles and would have carried on a bit longer; but now was when I needed to do the tires, since they were at the limit, hitting the bottom of the grooves in some places. It seems best to do all this dismantling and reassembly at one time if possible.
Front oem tire had 20566 miles at the time of replacement. Rear oem tire had 10728 ditto. Front 14 tooth sprocket had 20566 miles and rear 42 tooth sprocket had 43167 miles and both were now noticeably hooked, but not badly worn. This seems like the right point at which to change the sprockets.
The '01 engine I installed at 87K miles has about 29007 (the '01 bike had 1700 miles when I got it) miles so far on 5W-30 non-synthetic oil with no attention except oil changes and runs fine. This is mostly highway miles cruising 65-75 mph. Fuel mileage is always around 70 mpg on 87 pump gas.
The oem Yuasa battery I installed 2-02-06 was checked and the electrolyte level found getting down near the lower line, so I topped it up with distilled water. One trick I find useful is to mark the lower line on the back of the case with magic marker, since as installed one can't see the lines on the case. It is important not to let the electrolyte drop below the lower line because then the battery starts to suffer and deteriorate. The Yuasa oem battery previous to this one lasted almost four years and 31569 miles. I don't see much advantage to the maintenance-free later battery.
After three years exactly and 27337 miles since changing engines I checked the coolant overflow tank and found that the level was getting down near the L mark, so topped that up with 50/50 antifreeze. If there are no leaks this tank does not lose much coolant. Probably only by minute vaporization out the vent tube.
After 130 miles of satisfactory road testing on the replacement of tires, sprockets and chain, a few more thoughts came to mind.
Wanted to support what Old Marine said about riveting the chain master link. This is the best and most reliable practice. I didn't believe this until a few years back when the spring clip of a correctly-fitted Tsubaki master link came off and disappeared. Fortunately, the sideplates were so tightly fitted that the chain stayed together anyway, and I noticed it on a routine check. I replaced it with a rivet master link and have done with each new chain since.
You have to know what you're doing to rivet a master link but it's basically simple. My approach is to 'buck' the link from the rear with a torque handle inserted between the wheel spokes across to the link, after pressing the sideplate on with a big C clamp and a small socket that will go over the pin as it comes out.
With the torque handle against the link, I then work on the exposed end of the pin with a small ball peen hammer with careful hits. After a good many hits the end will become mushroomed over a little, similar to the machine-riveted heads of all the other links. You don't want to beat the protruding end down flat flush with the plate, that would defeat your purpose. A correctly-peened rivet master link is as reliable as all the rest of the links of the chain and this is a trouble-free business.
I understand tools are available that will do this job without the hammer work, but I don't have one.
Wanted to mention that the '01 front wheel complete with oem tire I've used on my '88 the last 20K+ miles has always been a little rough on the front brake. Giving a slight shudder and vibration, which was irritating but not serious. I suspected run-out in the brake disc, but didn't check it since there was nothing I could do about it anyway. During maintenance, I did put my dial indicator up against the disc and turned the wheel. It is hard to do this operation because hard to turn the wheel without moving it sideways a little at the same time. But I ended up with a reading of about .005" run-out on the disc. So this was the source of the vibration and shudder in the front forks under some braking conditions.
In replacing the original '88 wheel with a new oem tire on it, whose disc has almost 100K miles road service, I took the opportunity to check this one for run-out also, and it showed under .002". And now the brake is as smooth and pleasant to use as it should be.
So if you have any vibration or shudder of the front forks under braking, run-out of the disc is the place to look. Not that it is too easy to correct. The disc MIGHT be warped, or the hub area where it mounts MIGHT not run true to the bearings.
Last little tidbit is I noticed as at every time, the oem tires squirm a little bit on rain grooves when they are brand new, and I assume it's because of the sharpness of the central groove in them. After this wears a little, this squirming reduces to negligible.