The 10+ year KX500 rebuild thread

[Skub]

Fireworks!

[derek badger]

Fireworks!

Ring a fucking ding ding!

[Taipan]

Went and got 10l of fuel and knocked up some 32:1 premix. Well, it wasn't first kick but it fired up on about the 3rd or 4th once I'd remembered the knack. The carb needs to come off for a clean/rebuild but fuck my old boots...IT LIVES!!!!

Fooking aces! Well done!

[demographic]

I can't remember what carb the older KXs have, mines got the standard Keihin PWK39 D shaped slide but does yours have a PJ carb?

On about bits that break theres stuff on Youtube about the gusset kit that adresses some of the parts of the frame that break. It's aimed at the 88-2004 frames but still gives a good insight into what issues they have.
Realistically the main issue for mere mortals is the the expansion chamber bracket behind the coil.

Also Sandblaster and KX Guru have done some good Youtube vids.
They all break eventually.

[Potter]

Happy days!
That brings back memories.

[derek badger]

I can't remember what carb the older KXs have, mines got the standard Keihin PWK39 D shaped slide but does yours have a PJ carb?

On about bits that break theres stuff on Youtube about the gusset kit that adresses some of the parts of the frame that break. It's aimed at the 88-2004 frames but still gives a good insight into what issues they have.
Realistically the main issue for mere mortals is the the expansion chamber bracket behind the coil.

Also Sandblaster and KX Guru have done some good Youtube vids.
They all break eventually.

It's a Mikuni on mine with a round slide. I've got a choice of two. The one that came off the bike was in a shite state, someone had rammed a wooden peg in where the mixture screw was... I'll strip down the replacement I bought (currently on the bike) and give it a soak in the ultrasonic tank and a blow out with the airline.







As for cracks...it was properly fucking abused and unmaintained when I got it, but the mount for the spannie looks remarkable sound and so does the rubber mount.

[demographic]

Ahh, yeah.

If you look on Youtube there's a thing about shimming the frame of KX500s.
Now, I have to admit that I never really knew about shimming the frame for a good fit with mine but next time I take it to bits I'll likely brace the weak points and shim any areas that spring away from the mounting points.

In fact, its just simpler if I find the vid.

[demographic]

As I was perusing that Youtube last night I spotted this vid.
Now some things he's done are a bit questionable (carb and filter anyone?) but the way he's set up the decompression valve is interesting.
Personally I might be tempted to go up a size on the bolt diameter if possible cos I reckon its an M6 and with a 1/8" drill hole through it I'm not sure theres much meat left.

The decomp valve bit starts at seven minutes.



That position wouldnt work with mine cos the head design is different.

[derek badger]

Carb stripped and cleaned. Reassembly after lunch.

[Taipan]

Test ride soon! Test ride soon! Test ride soon! Test ride soon! Test ride soon! Test ride soon! Test ride soon! Test ride soon! Test ride soon! Test ride soon! Test ride soon! Test ride soon! Test ride soon! Test ride soon! Test ride soon! Test ride soon! Test ride soon! Test ride soon! Test ride soon! Test ride soon! Test ride soon! Test ride soon! Test ride soon! Test ride soon! Test ride soon! Test ride soon! Test ride soon! Test ride soon! Test ride soon! Test ride soon! Test ride soon! Test ride soon! Test ride soon! Test ride soon! Test ride soon! Test ride soon! Test ride soon! Test ride soon! Test ride soon!

[derek badger]

Test ride soon! Test ride soon! Test ride soon! Test ride soon! Test ride soon! Test ride soon! Test ride soon! Test ride soon! Test ride soon! Test ride soon! Test ride soon! Test ride soon! Test ride soon! Test ride soon! Test ride soon! Test ride soon! Test ride soon! Test ride soon! Test ride soon! Test ride soon! Test ride soon! Test ride soon! Test ride soon! Test ride soon! Test ride soon! Test ride soon! Test ride soon! Test ride soon! Test ride soon! Test ride soon! Test ride soon! Test ride soon! Test ride soon! Test ride soon! Test ride soon! Test ride soon! Test ride soon! Test ride soon! Test ride soon!

List of things to sort...

• Get it to run for more than 10 seconds. The carb is clean as a whistle so I need to check the ignition timing next. Also, my right leg is fucking killing me now...

• Axles/spacers/chain alignment.

• Brakes need to be fitted.

• Replace one of the shock bushes on the Uni-Trak tierods.

• Relocate the CDI unit and knock up a small loom.

• Fit the body work properly.

• Horn and speedo

Then get an MOT using frame number and letter of newness from Kawasaki, apply for registration with DVLA, insurance, tax it...

Only then can ride it unless I take it in a van to a private place.

[Taipan]

Well stop wasting time posting on here and get on with it!

[derek badger]

List of things to sort...

• Get it to run for more than 10 seconds. The carb is clean as a whistle so I need to check the ignition timing next...

So, the original CDI that came with the bike was deemed to be toast last time I tried to get this running. At some point during the lay-up of the project I bought a replacement off ebay and this is the one that I've just fitted and it produced a spark. It starts but roughly idles for 10 seconds a the most and won't rev out. Choke/no choke, any throttle opening...nothing. It tings along for a bit then stops.

The stator was brand new from Electrex World and is set up for standard timing, I've ignored the lighting coil for the minute and it's just the standard 4 wires for pickup, trigger, hall sensor etc. So with the carb cleaned and set to standard needle height and mixture setting I've gone back to the CDI unit and looked at it again. It has the right number of wire, but one is a different colour, looking at the workshop manual it turns out it isn't for an '83-'85 KX500 it's for an '87 KX250. While it seems to trigger a spark the timing map etc. will be all over the place and this is more than likely my issue. Just as well it didn't run 'properly' as there could have been a risk of detonation etc.

The CDI is another discontinued part direct from Kawasaki but I've found two companies, one in the USA and one in France that supply aftermarket ones. Meh. It's only fucking money, isn't it...

[Skub]

List of things to sort...

• Get it to run for more than 10 seconds. The carb is clean as a whistle so I need to check the ignition timing next...

So, the original CDI that came with the bike was deemed to be toast last time I tried to get this running. At some point during the lay-up of the project I bought a replacement off ebay and this is the one that I've just fitted and it produced a spark. It starts but roughly idles for 10 seconds a the most and won't rev out. Choke/no choke, any throttle opening...nothing. It tings along for a bit then stops.

The stator was brand new from Electrex World and is set up for standard timing, I've ignored the lighting coil for the minute and it's just the standard 4 wires for pickup, trigger, hall sensor etc. So with the carb cleaned and set to standard needle height and mixture setting I've gone back to the CDI unit and looked at it again. It has the right number of wire, but one is a different colour, looking at the workshop manual it turns out it isn't for an '83-'85 KX500 it's for an '87 KX250. While it seems to trigger a spark the timing map etc. will be all over the place and this is more than likely my issue. Just as well it didn't run 'properly' as there could have been a risk of detonation etc.

The CDI is another discontinued part direct from Kawasaki but I've found two companies, one in the USA and one in France that supply aftermarket ones. Meh. It's only fucking money, isn't it...

Yeahbut,spread over 10 + years,not so much. In case the missus asks.

[derek badger]

Yeahbut,spread over 10 + years,not so much. In case the missus asks.

Made to order, confirmed as the unit for the B1 KX500. €190 including 48hr DHL shipping. Order placed.

[Skub]

Yeahbut,spread over 10 + years,not so much. In case the missus asks.

Made to order, confirmed as the unit for the B1 KX500. €190 including 48hr DHL shipping. Order placed.

Awesome.

A mere 1.9 Euro per annum.

[cheb]

Yeahbut,spread over 10 + years,not so much. In case the missus asks.

Made to order, confirmed as the unit for the B1 KX500. €190 including 48hr DHL shipping. Order placed.

Awesome.

A mere 1.9 Euro per annum.

Proper man maths.

[derek badger]

Big thanks to Cheb for the rear axle top hats by the way! This will allow me to sort the rear brake hanger and chain alignment.

[Asian Boss]

Inspired by this I looked at CR500s on eBay. Eight large for a decent one. So your KX should be worth something when it's done.

[derek badger]

Inspired by this I looked at CR500s on eBay. Eight large for a decent one. So your KX should be worth something when it's done.

That'd be a fully restored MX one. But yes, the open class bad boys are now commanding a pretty penny. You should get one. Just right for impressing the school girls by hoiking a minger on the back wheel past the chip shop in your chavvy air max trainers and shell suit top.