KDXRIDER.NET

I'm looking for any information out there on fitment of a an 84 engine in an 87 frame. Also whether Jesus (complete generator assembly) is worth $425 to return my '87 KDX to it's former glory.

Also is it irony that I paid less than half that for the actual bike some years back, or just an investment in a wicked good old 2-stroke?

Wow that's not cheap!
Only you know the condition of your 87 and if it's worth it to fix. Do you have the time to fix it? Is there other major issues looming? But most importantly, are you tired of the bike and do you want to upgrade it anyway?

If the answers are yes no no respectively then go for it! I remember Juliend saying that this was a common issue. Maybe it's the only major one.
Good luck.
BTW post a pic of that 87. I'd like to see that.

Fletch wrote:Wow that's not cheap!

No that's not cheap, though flywheels and KDX rarely go in the same sentence as "cheap". LOL

I'm also weighing the option of dropping an 84 engine in but don't have good fitment specs yet, as well as considering rekeying a Tecate flywheel (I will post pictures and specs if I do that) or an alternative I heard for fitting 1990's flywheels and mated stator with cut outs on plate for +10 and -10 degree rotation.

My bike is average wear for the year, great frame (other than bad paint job by PO), great forks, shock, even good plastics though I have them all off, mechanically very sound except for rotor/stator, goes through gears fine and no play on either side for crank bearings or rod bearings, even the engine case is remarkably good. I restored an '82 PE 175 last year and sold it this past spring and my son (9 yrs) was quite upset, so this will be another project he and I can work on over the winter once I figure out the best path for the flywheel replacement.

Thanks for the reply!
John

Correct me if I'm wrong, but the '87 has a KIPS setup whereas the '84 does not? If your KIPS is working well in the '87, you might be disappointed in the power delivery of the '84. That said, I think the '87 has the same type of sub valves as the '89-'94, so they're probably NOT working, and you'll love the power delivery of the '84!

I guess what I'm trying to say is if all else is good with the '87 motor, you might want to explore one of the ignition swaps you mentioned and keep running it. If your KIPS machinery is trashed, then it might be worth retrofitting the '84 motor.

dfeckel wrote: if all else is good with the '87 motor, you might want to explore one of the ignition swaps you mentioned and keep running it.

Good point! The '87 does have the valves, I am talking with FRP which can do a retrofit for the '87 rotor and stator so I'll probably go that route, granted it's not a stock set up but this gets it running and preserves as much as possible with the stock engine/frame and saves me having to figure it out on my own so I can concentrate on other things.

Thank you for that.
John

I saw this add yesterday and was thinking about going and getting them, but I really don't need them. They are 15 miles from my house and I would be happy to help you two guys out with them if you were interested.

2 1987 KDX's

I have not called on them for fear of having to run over and buy them. This would definitely be the cheapest way to bring your bikes back to glory. They run so the stators and flywheels must be good.

Here's a couple pics of my 1987.

skythrasher wrote:I would be happy to help you two guys out with them if you were interested.

I appreciate the very kind offer but Jeff over at FRP says they sell a retrofit rotor & stator for $250 for the '87 so I figure I'll go with that to be a bit more assured the rotor won't spew magnets again. Though there's some merit in having a parts bike, and definitely better than the price quote I got on just the rotor and stator I got from a used parts dealer. Again, thanks for the thought!

I have a spare rotor and stator for my 87 "just in case". I could have made my money back ten fold on those parts, but I want to ride the bike and knowing I have a spare gives me the piece of mind to do so.

Keep your eye out, and you can find another compelte running 87 for that....and keep the nickel bore/etc.

skythrasher wrote:I have a spare rotor and stator for my 87 "just in case".

.
A very good point!