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87 ex500 in a basement

3237 Views 121 Replies 12 Participants Last post by  ducatiman
Hi, this is my rebuild thread. Bike was left in a field for a few years, then given to me as a wedding present. Intention is to build it up to be a ultra reliable, dialed in performance machine (within it's own limits) to be used at the track, and hopefully raced one day. Also will be nice to keep in the garage for the wife or visiting friends to be able to rip on.

let's see if this photo works to share:
New item by Chris Grannen

Here's a photo album of the progress:

Will update text tomorrow when back @ work.

Initial burning question:
Gen1 vs Gen2 flywheel. is it foolish to leave the gen1 flywheel on for reassembly? See photo album for reference image of current flywheel. some of the reddish coating is flaking on the magnets.

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The flywheel looks pretty good but.....
looks can be deceiving. You should opt for the gen2 flywheel upgrade.
How to modify a 2nd Gen flywheel for a 1st gen bike (by FOG)
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Sure fair enough
Thanks for the link, seems straightforward.

now…. As far as parts, why is the cheapest option on eBay set at like $180?? Any chance that another Kawi model used the same flywheel as the gen2? Seems like a new one could be had for just a few coins more than what they want for a used part.

also relevant… seems like this mod is more of a risk mitigation situation, more than any sort of performance enhancement. Is the risk worth $200 in parts and a few extra hours of labor? We consider…

if I could find a donor gen2 for under $100 it might make sense, but even that’s kinda pushing it. $60 or less wild be the sweet spot.

RMStator, who I have purchased things from before, also has a “upgraded” flywheel for gen1 ex’s… $229
seems like this mod is more of a risk mitigation situation, more than any sort of performance enhancement.
That's exactly right. In this case the risk of failure is high. The reason Kawasaki upgraded with the gen2.

Your goal,
Intention is to build it up to be a ultra reliable
May want to keep an eye out for a good deal ;). There are reliable aftermarket gen1 flywheels, can't say whether the one you mentioned is one of them.

Either way whether you want to do a preemptive preventative procedure or wait until you have no choice, looking forward to the progression of the rebuild thread. (y)
hi, you have a early gen 1 (4 fin head) fine, you want it to be ultra reliable fine, you want to race it, also fine.
from where you are to where you want to be is going to be a long sometimes difficult challenge, you will have to make some hard decisions on the rebuild and it's not going to be cheap.
you will find this out as you go along but be prepared there is a reason Kawasaki made the upgraded gen 2 in 1994,
to make a (very) short list.
1. flywheel you know about this already they shed the exposed magnets at anytime can be 2k or 50k you never know, call it a ticking time bomb, PITA if you wait too long.
2. CCT these are crap and will fail at any time, requires the later gen 2 ratchet type ASAP.
3. drum rear brake while these work well the drums go oval after a while and are not replaceable without an engineering shop to replace the liner. they also go rusty and grooved. quite quickly.
4. gearbox the gear select indents wear out and slider bushes also, over time this causes a false neutral between 2nd and 3rd gear leading to missed changes also they will pop out of gear on the engine over run. not a huge issue on road bike (when you get used to it) but racing, not so sure.
5. voltage RR can be problematic causing over/under charging of the battery. suggest the later type (non ex) Mosfet type regulator of the FH20 type.
6. 16in rims, with limited tire sizes and choice of rubber IMHO not worth keeping on this old bike going forwards gen 2's use 17in rims and a rear disc brake means also changing the swing arm to gen 2 but worth it in the end.

for general info also although the bike is basically same there are some major differences between gen 1's and gen 2's dont be fooled into thinking they are the same in some respects they are a different model. the wiring is different they use different parts and the sizes and design are different, something to consider during the build.

if you get into difficulties help is available on the forum good luck, looking forwards to your progress in this thread.
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My experience is, either you have a race bike, or a reliable daily bike both is not reality. You can street a race bike with body work swap and track day a street bike, but those are different situations and one is still not good for the other. @fog went through several bikes playing, and tweaking things and things failing. Albeit trackways are a blast and I totally like to see people get on a track and get the need for speed out of their system and in a safe environment.

I like the work area though!

Either way $180 buck for a already set up plug and play flywheel that will not explode on you is a win. They used to be had for cheaper when ex500's could be picked up all day long everywhere for cheap. You would then modify it and have spare parts, that that is going to be a lot rougher situation these days to accomplish.
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1. flywheel
2. CCT
3. drum rear brake
4. gearbox
5. voltage RR
6. 16in rims,
1) will prob spring for the $180 flywheel i guess. speed costs money, how fast are you willing to go?
2) my CCT, i noticed once removing the engine, has black RTV on it, so it was going to get inspected, and now replaced... found a gen2 for $40.
3) drum brake will be fine for the time being, just got some new shoes on it.
4) hopefully this problem stays dormant for as long as possible... i got a 1981 gs1100 that will sometimes click into a false N between 2 and 3 and on the street, it's annoying to say the least. on the track it's a real vibe killer coming out of a corner.
5) also put one of these MOSFETs on the GS, great upgrade, never worried about it since. i use it with a lithium ion battery and have had no issues, but some literature warns about a lack of compatibility.
6) luckily, bridgestone still makes BT45 battleax tires for these 16" rims. not many choices, but i have plenty of good experience with the BT45's on other bikes, so i'm happy to let the 16's roll for a while. i

Clarification on "race" bike is that I want to contest in at least one race on the machine before I hang it up. I don't intend to build a proper race bike. Track day machine is kinda the main goal, at least for the next few seasons to see how it does. the EX is such a small bike, (weight compared to the GS, height compared to the KTM) it will be very easy to get it in and out of the van on my own.

i understand a flywheel puller is m18x1.5, right hand thread? like this? puller bolt
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I use an 18mm spark plug thread chaser for a flywheel puller. Got it at Napa.
Glad to hear you can get those BT45's in 16". I had to switch to BT46's. Hard to find in 17" anymore.
i was looking for the 46's... supposedly a much upgrade tire from the 45. maybe they stopped making the 45, and all the 17" stock was bought up. any 45's left might be "old stock", getting older. might have to check the date code if i get a set of 45's.

good call on the plug chaser. save a few bucks after paying 28 bucks to ship that dam flywheel LOL
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also back of my mind but will have to get resolved @ some point:


custom adapters? would love some inspiration photos, especially w the rear brake rod to contend with.
Is she DRUNK? o_O
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Is she DRUNK? o_O
no Clive some wives are happy to have a motorcycle in the house ;)
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also back of my mind but will have to get resolved @ some point:


custom adapters? would love some inspiration photos, especially w the rear brake rod to contend with.
I stole these pics from @fog
Auto part Hardware accessory Metal
Auto part Vehicle Car Engine Fuel line
Tire Automotive tire Auto part Vehicle Wheel

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Much appreciated on the photos!!! Looks reasonable enough to mock up and fabricate as needed. That will probably be a next season thing… after establishing a baseline. I’m trying to be cognizant of not going overboard with upgrades and changes before I’ve even done a single mile on the machine. Plus, changes are always better appreciated when there’s a before and after for comparison.

Motor vehicle Automotive tire Machine tool Automotive design Gas

Motor vehicle Metalworking Automotive design Engineering Gas

Motor vehicle Engineering Gas Auto part Machine

Automotive tire Motor vehicle Automotive design Automotive exterior Rim

Motor vehicle Automotive design Engineering Gas Auto part

Got stoned a few nights ago and cleaned the motor up way nicer than necessary, but now it looks good, and it will be easier to keep track of any fluid leak issues obviously. Maybe I’ll hit the cylinders and head with a quick shot of touch up paint. I plan to hit the bottom end with a quick coat of semigloss rustoleum black once it’s all buttoned back up with the cover etc
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Two more questions:

Automotive tire Automotive lighting Bumper Synthetic rubber Rolling

this Allen head plug in the front of the oil pan. Pre-cleaning, it looked like it might have been weeping a bit of oil @ some point. What is that plug for? Don’t want to disturb it, but couldn’t find the part listed in the OEM parts fiche

Font Cross Gas Wood Concrete

Brake caliper. The little end caps for where the pads sit on the caliper.Is that just a cover to inhibit caliper wear? Reduce brake noise? Long story short I’m using two EX calipers on my GS1100 and at some point I lost a pair of these small end caps and I wonder if it’s worth $17 plus shipping for each of them to replace. I have been using only one per caliper for a while now and haven’t noticed any difference.

thx for the indulgence
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Aftermarket sealed magnet stator arrived today. Looks legit. Single trigger point. Bolt on. Made in china.

Automotive tire Wheel Motor vehicle Alloy wheel Rim

Light Automotive tire Wheel Motor vehicle Vehicle brake

Wheel Automotive tire Tire Bicycle part Vehicle brake
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hi, the allen bolt at the front and the one on the side are something to do with the oil pump pick up, the clips on the calliper are to hold the pads in place, should really be on as it can allow the pads to move sideways when in operation.
not sure how far you want to go with the engine do up but seeing as how the engine is out might be prudent to change the water pump mechanical seal. and closely inspect the rubber engine mounts if there cracked replace them to reduce engine vibrations, yes there will always be some vibration as the rear top engine bolt is solid to the frame but those front ones can make one hell of a difference.
the flywheel looks fine several members have one without any issues.
Your cams are looking good. I like the way you put all the bolts back in their place rather than storing them in boxes or jars.
What's the story with the water pump cover?
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