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Re: The 10+ year KX500 rebuild thread
Posted: Wed Feb 10, 2021 2:31 pm
by derek badger
cheb wrote: Wed Feb 10, 2021 1:54 pm
I've just remembered I need to do the other spacer for you.
I'm just working out the front axle spacers at the minute. I'll drop you a PM with the final dims for all four, but no rush as I've got plenty to do still. Cheers mate.
Re: The 10+ year KX500 rebuild thread
Posted: Wed Feb 10, 2021 2:46 pm
by cheb
No worries.
Re: The 10+ year KX500 rebuild thread
Posted: Wed Feb 10, 2021 9:02 pm
by derek badger
Re: The 10+ year KX500 rebuild thread
Posted: Mon Feb 15, 2021 10:14 am
by derek badger
CDI unit arrived and is well made with the correct colour wires and terminal genders. Fitted it and it produces a decent spark, however I couldn't get it to fire more than a couple of times and then it wouldn't fire at all. Plug was wet so I suspect it was flooded, turn it over a few times by hand with the plug out and leave it until Saturday.
Same again on Saturday, and I give up as my right calf is fucking killing me. Sunday I take the carb off as I notice there is a puddle of petrol on the floor. I then take the intake boot off and the reed block. Fucking hell, I forgot how big the 6 petal Boysen reeds and the intake/transfer ports are!
Peering in with a torch I can hear the sound of premix sloshing about and have a think about how to drain the crankcases and remember I've got a Mityvac in one of the drawers. About 200ml came out! Looks like the needle valve on the carb isn't seating or the float is sticking so I've got the carb (and a spare one) in bits and will try and get it rebuilt today/tomorrow.
Re: The 10+ year KX500 rebuild thread
Posted: Mon Feb 15, 2021 1:44 pm
by derek badger
Axle spacers arrived in the post from Cheb today and are a perfect fit. Once the front tyre arrives (stuck in Holland for some reason) and I've got them both fitted it'll be much easier to move about.
Re: The 10+ year KX500 rebuild thread
Posted: Mon Feb 15, 2021 4:19 pm
by cheb
That's good to know, I forgot to send you the tracking number at the weekend.
Re: The 10+ year KX500 rebuild thread
Posted: Tue Feb 16, 2021 6:33 am
by derek badger
Replaced the valve and tweaked the float height. Seems okay now.
Re: The 10+ year KX500 rebuild thread
Posted: Tue Feb 16, 2021 8:06 am
by derek badger
Potter wrote: Tue Feb 16, 2021 7:44 am
derek badger wrote: Tue Feb 16, 2021 6:33 am
Replaced the valve and tweaked the float height. Seems okay now.
So does it run?
I ran out of patience and time last night when it lost spark. I'll be cleaning all earth points, trying a new HT lead and checking the stator again today.
Re: The 10+ year KX500 rebuild thread
Posted: Tue Feb 16, 2021 8:56 am
by KungFooBob
Always, always, always try a new plug first.
Several years racing a two stroke taught me that.
Re: The 10+ year KX500 rebuild thread
Posted: Tue Feb 16, 2021 9:14 am
by derek badger
KungFooBob wrote: Tue Feb 16, 2021 8:56 am
Always, always, always try a new plug first.
Several years racing a two stroke taught me that.
I've got 2 new plugs. A BR8EG and a BR8EG, both have been in boxes for 10 years unused.
Re: The 10+ year KX500 rebuild thread
Posted: Tue Feb 16, 2021 11:18 am
by derek badger
derek badger wrote: Tue Feb 16, 2021 9:14 am
KungFooBob wrote: Tue Feb 16, 2021 8:56 am
Always, always, always try a new plug first.
Several years racing a two stroke taught me that.
I've got 2 new plugs. A BR8EG and a BR8EG, both have been in boxes for 10 years unused.
Always, always check the wiring is connected correctly after you disconnect things when you've been drinking cider. The 2 x wires from the CDI to the coil and earth are B and BW. The two wires from the coil/kill switch are B and B...I've now marked one of them with white tape.
Still can't fucking start the beast though. It fired a couple of times but by fuck it's hard work even in Moto-X boots. I've got Thu & Fri off work so I'll make sure I have me weetabix those days.
Re: The 10+ year KX500 rebuild thread
Posted: Tue Feb 16, 2021 11:54 am
by cheb
The sprocket, have you got anything close to you what you need that could be drilled to suit?
Re: The 10+ year KX500 rebuild thread
Posted: Tue Feb 16, 2021 12:55 pm
by derek badger
cheb wrote: Tue Feb 16, 2021 11:54 am
The sprocket, have you got anything close to you what you need that could be drilled to suit?
To bump start it?
Re: The 10+ year KX500 rebuild thread
Posted: Tue Feb 16, 2021 1:23 pm
by demographic
Got to admit that I've never found mine right easy to bump start.
Long travel suspension, high seat and a fair dollop of compression made for hard work even on tarmac.
Then after a while the kickstart knuckle wore so it overrotated and my foot would sometimes slip off.
Upto that point it was usually first or second kick but thats a whilemumbleswerveages ago.
I keep eying up the decomp conversion cos MX boots are bloody shite for normal use. I don't mind wearing workboot type of things but can't be done with stomping about like Robocop everytime I want to ride a bike.
Re: The 10+ year KX500 rebuild thread
Posted: Tue Feb 16, 2021 1:31 pm
by derek badger
Re: The 10+ year KX500 rebuild thread
Posted: Tue Feb 16, 2021 4:47 pm
by cheb
Not for bump starting, for checking if the gears etc work or a gentle test riding once you get it running.
Is it road registered?
Re: The 10+ year KX500 rebuild thread
Posted: Tue Feb 16, 2021 4:58 pm
by demographic
Oh and if you do have a go at bumping it, first make sure the clutch can free up or you could end up with some nasty skidmarks when it fires up.
Or so I've read anyway

Re: The 10+ year KX500 rebuild thread
Posted: Tue Feb 16, 2021 6:58 pm
by derek badger
cheb wrote: Tue Feb 16, 2021 4:47 pm
Not for bump starting, for checking if the gears etc work or a gentle test riding once you get it running.
Is it road registered?
Gears all select okay, it's had a full rebuild and I trust my mechanic that he'd have noticed any broken bits when he did it. It isn't registered yet, but will be. MOT via van transport is the plan. I've got not rear sprockets that would work so I'll wait for Talon to deliver.
Re: The 10+ year KX500 rebuild thread
Posted: Tue Feb 16, 2021 7:32 pm
by cheb
OK, that would have been my next thing, to get it to the tester sooner.
Re: The 10+ year KX500 rebuild thread
Posted: Wed Feb 17, 2021 5:32 pm
by derek badger
Christ. I just found the receipt for the rebuild from 15 years ago...
