Winter fettling and mods

Here's a chance to show off your zxr400, so get them digital cameras out and show us some piccies.Rebuilding your bike or modding it then let everyone in on it.

Moderator: Moderators

Post Reply
User avatar
Tirpitz
zxr400 oc member
zxr400 oc member
Posts: 766
Joined: Sun Dec 12, 2010 2:45 pm
My Bike: Kawasaki ZXR400L4
Location: Doncaster, South Yorkshire

Winter fettling and mods

Post by Tirpitz »

I like to save servicing and big jobs for the winter layup so that with the bike off the road anyway there's no rush to get on. Plus, summer's for riding, not tinkering. This year, as well as a major service being due I had some restoration and modding in the pipeline. I'm lucky in that I have a shed big enough to work in with lighting and power which I installed for winter work.

The bike has done 11383miles now so I decided to do the 12k service early. Rather early than late. As well as all the minor, routine servicing tasks the following was done-

1. Valve clearances checked and adjusted. First time I've done this, they were done at 6K by a dealer. Mori Man's guide was a great help, I had done screw and locknut clearances before but not shims. I did it with the engine in the frame no probs but I would say that IMO removing the plug funnels is essential. You can't really get feeler gauges in properly with them in place. I put new o-rings in as recommended by the Blingmeister - they don't cost much, why risk a cock-up? You will find that you have to remove the rad fan so give yourself room to get at No.2 exhaust rockers to move them out of the way - 3 bolts, job done, why struggle? Now, my engine was running sweet with plenty of power, yet 11 of the clearances were out, a few badly. Moral of the story is don't think you don't need to do this job because your bike sounds ok and is running fine :smt018 . It will probably continue to do so until it goes bang. The clearance checks are a periodic maintenance task for a reason - do it. Tip when replacing the rocker cover - be careful not to overtighten the bolts. It's easy to do even if you do the job 'properly' with a torque wrench because if you have the engine in the frame with carbs on there isn't much room to swing the wrench it just turns a few clicks of the ratchet at a time without releasing on the limiter. As you tighten them they squash the rubber gasket until the unthreaded shoulder hits the cam shroud they are threaded into. They won't screw in any more no matter how much you tighten them up, all you do is stretch the threaded section until it snaps (which also means that if you have a leaking gasket, if the bolts were tightened properly, tightening them up some more won't help, you need to replace the gasket). All you need to tighten them properly is screw until you feel they have hit the shoulder, then just nip them up a fraction of a turn. You're only stopping them unscrewing, you won't be helping any giving it a big fistful.

Don't be afraid of doing this job. Provided you equip yourself with the required tools and work carefully (DO block all oilways and tunnels with rags - don't miss the three oilway tunnels in the head underneath the exhaust cam, they will be filled with oil and 'hidden') and take your time it is nothing to be scared of.

2. Rear suspension removed from bike and regreased. Make sure you do this job when it is due as the bearings ex-factory will probably have had very little or no grease. A rear suspension that works properly is worth a few hundred £ in tuning work. You will need a bike jack unless you can strap the bike to a roof. If you are going to work on sportsbikes a jack is an investment that will pay you back as centrestands are a thing of the past. My bike has seen virtually no rain yet the swingarm pivot pin was pretty seized in and the ball bearing was as dry as a desert - again, don't assume if it seems ok that it is ok.

3. OEM rear shock removed. Worst part of the bike, Kwak let themselves down with that pile o' shite. Nitron Sport shock fitted made for my weight. They got it set pretty right from the factory, I only needed to back off the preload about a turn and a half to give a perfect rider sag setting. Looks the dog's too :smt004

4. New OEM brake pads fitted to the front. The Ferodos I was running had only done 5k but they felt wooden and not very sharp. I dunno if they deteriorated during the years the bike was laid up (reading online suggests pads don't go off, so :smt017 ) but when I took them off for a looksee they were crumbling at the edges and in a few places there were craters in the surface where material had crumbled out :shock: Might have had something to do with the feel....... :smt003 They were visibly ok when the bike was restored. What I saw tightened my ringpiece up a bit.

5. Exhaust system removed from bike and headers emery papered clean of surface rust and repainted with Rustoleum BBQ paint from B&Q. I've read a bit about this stuff in resto mags being the dog's, a lot better than dedicated exhaust paint. It contains a rust killer. Certainly went on fine and looks good. It has touch dried but it will cure hard when the bike is running. The headers were only just starting to show signs of rust but rather than leave them to rot before acting I thought I'd strike quickly.

6. Rad and oil cooler stone guards were just starting to show outbreaks of surface rust so they were removed, cleaned, primed and resprayed with Plasticote black satin.

That's pretty much it so far. On top of the normal full service it was a lot of work and took many hours but very fulfilling. The main PITA was, as with all supersports bikes, that so much needs to be removed before you can get at components or to give access for tools. That's why I would say you need to give yourself the time and facilities to get on methodically and be able to leave it dism,anted and come back to it later. If you rush or try shortcuts you'll come unstuck.

At present the bike looks like this -
0021.JPG
0011.JPG
0041.JPG
I need to balance the carbs but I'll do this in a few months as the bike is currently drained of petrol for winter storages. The job I'm going to get on with in a few days is to grease the headstock bearings - again an easy job to neglect but one which will come back and bite you. I'm in the process of obtaining a 36mm socket for the top yoke nut as I have nothing big enough to shift it and will need torqueing back down when I've done. I've had a look at the job and I suspect it can be done easily without taking off all the ancillaries and clip-ons. With a jack under the engine, once the top yoke is off and the steering stem locknut off I'm thinking that jacking up the front of the bike a few inches will be enough to drop the stem through the headstock enough to get at the bottom bearing, clean it up and regrease. Then lower it back down, reassemble and job done. Again, the jack is your friend and if the above works then there really is no reason to to skip what should be an hour's job (famous last words :smt012 ).
You do not have the required permissions to view the files attached to this post.
ZXR400 L4, purple / black / pink
Hel braided hoses
Pirelli Diablos
Ohlins steering damper
A16 carbon fibre exhaust can
Nitron Sport shock
cargo
zxr400 oc member
zxr400 oc member
Posts: 3341
Joined: Sat Jan 08, 2005 10:33 am
My Bike: tomos moped
Location: Carrickfergus Northern Ireland

Re: Winter fettling and mods

Post by cargo »

The top yoke does NOT come off you need to drop the bottom yoke down first.

It's a security feature to stop the lock set being removed
User avatar
Tirpitz
zxr400 oc member
zxr400 oc member
Posts: 766
Joined: Sun Dec 12, 2010 2:45 pm
My Bike: Kawasaki ZXR400L4
Location: Doncaster, South Yorkshire

Re: Winter fettling and mods

Post by Tirpitz »

You've totally confused me now Cargo. So how do I get to the top bearing and how would I get the locknut etc off if the top yoke doesn't remove :smt017 All that gubbins is underneath the top yoke. Won't it come off if you unscrew the lock barrel which seems to be held in place by two bolts which are inserted from the underneath?

Or are you saying that if I loosen the lower yoke clamp bolts on the forks that then the top yoke (attached to the forks still) will push upwards and clear of the headstock so I can get in?
ZXR400 L4, purple / black / pink
Hel braided hoses
Pirelli Diablos
Ohlins steering damper
A16 carbon fibre exhaust can
Nitron Sport shock
cargo
zxr400 oc member
zxr400 oc member
Posts: 3341
Joined: Sat Jan 08, 2005 10:33 am
My Bike: tomos moped
Location: Carrickfergus Northern Ireland

Re: Winter fettling and mods

Post by cargo »

Cant remember the exact procedure but for sure just taking the top nut off will not release the top yoke cos the ignition switch catches on a lug

I think once the forks are out and the top nut is gone then the top yoke will turn on the stem and come away
User avatar
Tirpitz
zxr400 oc member
zxr400 oc member
Posts: 766
Joined: Sun Dec 12, 2010 2:45 pm
My Bike: Kawasaki ZXR400L4
Location: Doncaster, South Yorkshire

Re: Winter fettling and mods

Post by Tirpitz »

Ok, I'll see if I can get a workaround by removing the ignition switch from the top yoke first via the two bolts which secure it underneath. I want to avoid taking the forks out as I just want to grease the bearings. If I was taking the stem out then it wouldn't matter, it would all have to come off anyway, but I'm trying to do the least amount of work just to clean them up and get some grease in there. If I work out a quick way I'll post it up.

As said before, this is the problem. You want to do a half hour job and spend the best part of an hour taking crap off left right and centre just to get in there :smt011 Dontcha just love working on bikes.
ZXR400 L4, purple / black / pink
Hel braided hoses
Pirelli Diablos
Ohlins steering damper
A16 carbon fibre exhaust can
Nitron Sport shock
User avatar
Tirpitz
zxr400 oc member
zxr400 oc member
Posts: 766
Joined: Sun Dec 12, 2010 2:45 pm
My Bike: Kawasaki ZXR400L4
Location: Doncaster, South Yorkshire

Re: Winter fettling and mods

Post by Tirpitz »

Whoa, just a second, thinking about this some more I think we're getting at cross purposes here. You're right that I won't be able to LIFT the top yoke off because of lug but my original method will still largely work. I will be removing the top nut and releasing the forks from the top yoke clamp. When I then jack the front of the bike up under the engine the stem and forks will drop out of the top yoke. It will then be possible to slide the yoke forward with ignition barrel attached clear of the lug, then lift clear to get at the top bearing. So it should all work with the minimum amount of dismantling.

Will let you know how it goes.
ZXR400 L4, purple / black / pink
Hel braided hoses
Pirelli Diablos
Ohlins steering damper
A16 carbon fibre exhaust can
Nitron Sport shock
cargo
zxr400 oc member
zxr400 oc member
Posts: 3341
Joined: Sat Jan 08, 2005 10:33 am
My Bike: tomos moped
Location: Carrickfergus Northern Ireland

Re: Winter fettling and mods

Post by cargo »

yeah thats it
User avatar
Tirpitz
zxr400 oc member
zxr400 oc member
Posts: 766
Joined: Sun Dec 12, 2010 2:45 pm
My Bike: Kawasaki ZXR400L4
Location: Doncaster, South Yorkshire

Re: Winter fettling and mods

Post by Tirpitz »

Ok, so job done and the quick way to get at the head bearings does work. I'll post up a separate explanation in the appropriate thread to help others in future to do this job. Bearings actually had some grease in them shocking and were in excellent nick, so simply cleaned out the old and refreshed with new :smt001
ZXR400 L4, purple / black / pink
Hel braided hoses
Pirelli Diablos
Ohlins steering damper
A16 carbon fibre exhaust can
Nitron Sport shock
Post Reply