ZXR400 Track bike build

[patchb]

A few weeks ago a guy at work asked me if I was interested in a ZXR400 that he had owned for the past 8 years. Hes never had a bike licence but bought the bike as a project, put a new engine in it and sent the fairings off for paint, then forgot about it and it sat in his garden for 8 years.
This was the only photo I saw of it before I went to pick it up:



It's going to require a lot of work but I'm keen for a project. The aim is to have it rideable for September 22nd as my old man and a couple of his mates are doing a classic track day at Cadwell and I want to join them. Neither of my other bikes are suitable as its for pre '94 bikes and they are '98 and '09. As long as it is in a usable condition for that I can finish off any bits and bobs over winter.
I've got the freshly painted fairings for it but I will be selling them as I will be fitting track fairings. It will have a daytime MOT so I can do shakedowns on the road.
So far my plans include but are not limited to:

Rear brake conversion (gets rid of the heavy torque arm)
Fork seals and oil
Rear shock replacement (ZX6R)
Oil and filter change
Valve clearances
Strip/bleed/new pads in front brakes
Clean and refit carbs
Rearsets
Check headstock and wheel bearings
Grease swingarm/shock linkages
Remove unnecessary components and wiring from loom
Remove excess rear subframe/components
New starter relay
Paint/Fit fairings
Tyres

So I went and collected it yesterday, things didnt look good, the engine was pretty furry from oxidation:



So I gave that a bit of a clean up. I wanted to use brick acid (we use it on boats at work for oxidation and it works a treat) but I couldn't get hold of any due to the current trend of s throwing acid at people. So I used a bit of vinegar and some scotchbrite which worked to clean up the furring but it does need a bit more work:



I clicked it into gear when I was rolling it around the garage and noticed the clutch is siezed. Whipped the clutch out, all the plates were stuck together so I have soaked them in some engine oil and refitted, all good now. Also set to work removing some excess from the loom. As it is going to have an MOT I need to keep the clocks and wanted to keep the fan so there wasn't loads I could remove. Still I reckon that lost a kilo or so and less wires to get in the way. Before:



After:



It's got braided hoses fitted, for some reason someone has gone for one yellow and one pink



I removed the rear section of subframe as its heavy and useless with the race seat unit. Then decided to try the tank on just so I could have a sit on it. (it's quite small for me at 6'4"!)



Thats all I've done at the moment. I've ordered a new starter relay and will be cleaning and refitting the carbs tomorrow so I'm hoping to have it running by the end of this week. Also ordered fork seals and a new front brake lever. Will also be checking bearings this week so I can get them ordered and fitted if required. Hopefully progress will be fairly quick on this and I can update almost daily (if anyone is actually interested!)
Once I've ordered the fairings I will be trying to design a colour scheme for it, my Dad owns a bodyshop so getting those and the wheels painted won't be a problem.
I've also got a spare engine that had dropped a valve so I'm considering building that to a decent spec but thats not a priority at the moment.

This bike is my inspiration:

[Darkslider]

Cracking little bikes, I had an l3 as my first ever bike, and would definitely have another in my post lottery win fleet. Best out of all the proper 400 race reps in my opinion.

[mckeann]

good luck. I will watch with interest.

Old bikes scare me a little, I've never even owned a vehicle with carbs fitted, but I'm about to start helping my dad strip and rebuild his old 1959 Norton which is slightly terrifying

[patchb]

IT RUNS!

After a lot of fiddling about with electrics and about an hour of cranking it over, playing with the carbs and it coughing it finally fired up on Saturday morning. Once I'd fired it up a couple of times it would idle and rev quite nicely considering the coils have seen better days and the carbs aren't set up.

That's spurred me on a lot, I'm happy to order the fairings now, I didn't fancy spending out on them if it wasn't going to run any time soon!

So over the weekend I have done the following,

The front brakes were disgusting, however the pistons all moved, so I pumped them out, gave them a good clean and bled the system through with fresh fluid. Also cleaned up the hoses and fitted a new lever, all good now.

Untitled by patrick burrows

Fork seals needed doing so I pulled the forks out, gave the internals a good clean up, seals and rebuilt. Filled with slightly heavier weight oil and slightly less air gap than standard. The stanchions have some thin chrome so I think they will leak again at some point but they are sorted for now. I will fit some newer forks if they do prove to be troublesome as I don't think spending £180 on having the stanchions rechromed is worthwhile on forks that aren't fully adjustable. (the leaky pic is before seals)

Zxr by patrick burrows
Untitled by patrick burrows

Whilst the forks were out I thought I would attend to the headstock bearings. They had no play in them but weren't the smoothest things after 8 years sat outside. A good clean and packed full of fresh grease and they feel good again (again, photo is before cleaning and greasing)


Untitled by patrick burrows

So front end back together and all good. I also checked the wheel bearings whilst it was all apart and they are spot on. Fitted some nice new renthal grips to finish off the front end. Although I say finish off, it will all be apart again for paint and cleaning but at least everything up there is mechanically good:


Untitled by patrick burrows


I've got a new set of carbs on their way to me as i stupidly managed to snap the mounting lug for the throttle cable off of no.4 carb!!

Untitled by patrick burrows

Also chain was left to soak in oil for a couple of days, cleaned up, lubed and refitted.

Also on their way are a new exhaust hanger, fuel tap seals, plug caps, coils and HT leads and I have got a set of Supercorsa scrubs that I need to go and pick up tomorrow evening. I need to purchase a rear shock, this will be coming from a J/A1P zx6r, just need to find a low mileage one.I think I have everything I really need then, just fairings to order and paint, wheels to paint and put everything back together and working nicely. The rear brake is something I need to source at some point but I think I will get the bike running with the stock one for the time being.

[SteelerSE]

Great job. Sounds like you're most of the way there.

[Fleegle]

Nice project, but ffs stop biting your nails

[Jazoli]

Fleegle said:

Nice project, but ffs stop biting your nails

and wear disposable gloves

[horico]

Nice project. I always wanted one of these when I was a teenager and used to pop in to the local bike shop on the way home from school for a look round.

While my proportions won't positively assist the power to weight ratio nowadays, I still want to own one at some point!

Keep up the good work!

[patchb]

horico said:

Nice project. I always wanted one of these when I was a teenager and used to pop in to the local bike shop on the way home from school for a look round.

While my proportions won't positively assist the power to weight ratio nowadays, I still want to own one at some point!

Keep up the good work!

No I don't think I'm ideal for it at 6'4" and probably 16 stone in kit but should be fun.

To be honest if I were to choose a track bike it probably wouldn't be one of these but given the circumstances I couldn't say no really

[patchb]

Fairings arrived today. They are from a company called Sforza racing. They seem OK, very thin, I think I will add some extra fibreglass to the mounting points. Any modifications I need to make will be easy as I've done a lot of laminating before, I would have made the fairings myself if I'd had the moulds.

Gave them a quick test fit this evening. I need to think of a colour scheme, I want 90's kawasaki race bike look but something quite loud and brash. Anyone got any ideas???

Untitled by patrick burrows
Untitled by patrick burrows

I need to source a mudguard as I gave the one I had away with the original fairings, tank forward cover and a screen. Ideally I want a tall TT style screen but may have to settle for a clear double bubble. Should look a bit more racey when I get the supercorsas on as well, just not bothering to swap the tyres until I've thought of a livery and get the wheels painted.

[SteelerSE]

What about:



Or do you want to stay with green so that you can leave the tank as is?