Finally got around to replacing all the vacuum lines last week, along with new clamps for the manifolds. Unfortunately it must still have an air leak somewhere as the 7,000rpm flat spot is still present, though nowhere near as bad as when I first got the bike... Have to find some more time to work on it... Just a matter of spraying brake cleaner at bits until I find the leaks. Had the steering head bearings adjusted too, but after riding it it's clear they need replacing. The work never ends...
Time to address some comfort related problems I have on the ZXR. The big one for me is the seat and how it slants forward towards the tank. That and it is rock hard, plus the cover has gone old and hard with age. Since I was involuntarily deprived of a nut, having the remaining one squished forward into the fuel tank is not ideal! The next item on my list was some tank grip. My criteria was that it had to be clear and a good grippy texture. While picking up some new kevlars and knee sliders at MCAS, I spotted some suitable grip pads and grabbed them quick smart. As for the seat, I am going to get a professional upholstery job done on it, arse mold and all.
Loving your work mate, picked up a ZXR250C on the weekend myself. It's a bit more of a basketcase than yours started as. Good to see so many giving love to the old 250 4's, can't wait for later updates and to see how the Ninja 300 boots hold up.
Thanks. The ninja 300 coils are doing well. I need to replace the spark plug seals under the rocker cover, and probably the o-rings under the one piece camshaft cap as well. I have a set of steering head bearings waiting to go in, rearsets and caliper bits ready to go in thanks to @Andych and failing that, coerce rearsets from japan look good, and i have been eyeing the ateering damper for a while too. I now think my flat spot issue is the bike in need of jetting changes as I have an aftermarket air filter and pipe. Charging system is long sorted, thank god. Recently figured out my right handlebar is bent by a bee's dick, but ita enough to give me hand cramps. I want to remove the 2nd throttle cable for a lighter throttle turn... maybe quick turn throttle tube as well. But mostly im enjoying riding around... playing the 'cant get 1 more demerit point for 3 years' game...
So I'm doing my steering head bearings at work tomorrow. Has anyone done them on a ZXR before... any gotchas eg having to grind down the stem to fit aftermarket bearings? It's an all balls tapered roller kit #22-1015 that I bought off ebay, but it doesn't have zxr250 on the applicable models on the packaging. Will get some photos tomorrow too.
Grinding down a steering stem? .... fuk me , what do they teach you there ..... get the correct bearings if they dont fit https://www.xpsa.com.au/22-1025-kawasaki-zxr-250-import-1988-1998-steering
Have your dremel and some cutting discs handy just in case there are no cut outs to knock the bearing cones out of the headstock. Sent from my iPhone using Tapatalk Pro
Jumped the gun a bit there... we do not do that sort of thing... i have hears of some older bikes that require modifications to accept tapered roller bearings... which are way better at dealing with thrust loads compared to ball bearings. Yeah we have all that and more at work.
Apparently the secret with the tapered roller bearings is to initially do them a bit tighter than you would on the old bearings. They settle quite quickly and if you set them as you normally would they become very loose quickly. Sent from my iPhone using Tapatalk Pro
Cant ******* trust ebay listings... bloody bearings were wrong. Bit of a disaster as removing the lower bearing meant cage came off and fell to pieces. Work had one correct bearing/race in stock, used that on the lower bearing, cleaned up and regreased the one old bearing and used the best of the leftover races, rotating it from its original spot which 'moves' the notch. Got another bearing on the way... I adjusted the pilots 1/4 turn out each to 2.5 turns, starts easier hot and cold, idles better, better throttle response, bit more power and running cooler. After averting that disaster I had a play with the front suspension settings. I set the preload so that 11mm of the adjuster is protruding (range 20mm softest 5mm hardest). Stiffened up both the damping adjustments and went for a ride... pretty good... back in and softened the compression damping one click. No more clunk from steering head or oscillations at 30-40km/h. Battery on trickle charger throughout the day, just to keep it topped up. Pics to follow
After getting the bottom triple and stem out, I had to get the bearing off... dome by using a big brass punch and hammer with the tree held in a vice (with soft jaws and a rag) and tap the punch between the bearing and the stem until it comes off. Getting the new one on is a bit more difficult. I used the old inner race and a cut down BMW fork to press the new bearing on by the inner race, in the hydraulic press. Knocking the top outer race out was easy enough. The bottom outer race was more difficult as there was no relief to get a punch on the lip of the race. Took a piece of 1/2" (i think) round bar and ground a long 'v' relief cut into it, and concaved the end of it a little using the bench grinder. This allowed me to knock the lower outer race out without using a dremel to cut into it. As mentioned the bearing kit was wrong. Both the old bearings are numbered 32005JR. Since I couldn't leave it til monday (work policy for staff working on their own bikes, in and out on the same day) and have it occupying a bench, I fitted the new bearing on the stem as it takes most of the load. To complete the job I only need to replace the top bearing and race at a later date. I also replaced the left rearset with the one I got from @Andych - it worked a treat, thanks. Unfortunately the rear brake bits won't fit as they are A model stuff... however the caliper is a dual pot, C model is a single pot. Might look into converting it.
After my huge trip down to tumbarumba/mount hotham/Omeo hwy, my steering head bearings have come loose again. I still have the old top bearing in, the new one is sitting here waiting to go in. They were done up fairly tightly initially. Got a second hand set of front blinkers on the way, and a another set of swing arm spools, then I should be good for a while... Bummed I couldn't make th gunnedah drags this weekend
The bolts are M12 fine thread. I just searched eBay for 12mm spools. I wanted anodised orange ones but none were available, so I went with silver again.
More jobs done. Finished steering head by replacing top race and bearing. Pulled the top race out New race in Bearing getting packed Back together and tensioned what felt tighter than it should but felt fine once the whole front end was back together. Next job was a new rear disc and pads. Red loctite on disc bolts... sigh... I found one of the caliber slides seized as well, causing uneven pad wear. Pulled the bracket off, cleaned and lubed the pins and back together. Then a clean, lube and adjustment of the chain since the rear wheel was off. Front end is great now, no more clunks and moments where the steering decides to point somewhere other than where you tell it. Disc and pads needed for rego. Replaced the swingarm spools, I thought the right one was bent but it was the swingarm mount point for it. Muffler off, old M12 bolt in, a dozen or so firm raps with a hammer and it's square again. Went home and hit the sack... flu/cold thing has hit me.
Having issues with the rear brake. Feels weak and have to really stomp on it to get it to work hard or lock the wheel. Inner pad is only contacting the disc on the outer half of the disc, if that makes sense. Fluid done 1 yr ago. Pictures to clarify Outside Inside Previously one of the slides was stuck and causing cock-eyed pad wear, which stuffed the old disc. The pins that the inside pad sit on are worn, the part is NLA, even megazip couldn't get it for me. Ideas?