Author Topic: Differences between a 90 500 crank and a 02?  (Read 12596 times)

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Offline zz3gmc

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Differences between a 90 500 crank and a 02?
« on: January 03, 2015, 04:57:37 PM »
Can anyone tell me what the differences are between a 90 KX500 crank and a 02? Are the crank tapers the same? Are flywheels interchangeable?

Offline sandblaster

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Re: Differences between a 90 500 crank and a 02?
« Reply #1 on: January 03, 2015, 06:54:46 PM »
The four stroke engine: That's one stroke for producing power and three for wearing the engine out.

Offline Foxx4Beaver

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Excuse me, ma'am...but you've got extremely nice legs!!!...what time do they open???                                                                                                               https://www.youtube.com/watch?v=n8tCgN3aryQ

Offline dave916

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Re: Differences between a 90 500 crank and a 02?
« Reply #3 on: January 04, 2015, 04:21:07 AM »
http://www.oem-cycle.com/forum/viewtopic.php?f=5&t=632&p=2462#p2462

I'm running a 89 crank in my 01 engine..

great write up.
Expect for a few errors :lol:
""The 91 and earlier cranks have holes in the crank that make them lighter then the 92-04.""   88 and earlier have the crank holes/ it does Not make them lighter
""So my best prognostication is that 85-04 can all be swapped as long as you have the correct primary crank gear asy to match the crank you are using." " pre 87 cranks can not be used with 89on cases
""From what I can see, 85-87 kx500 crank shafts look identical.""    87 was first year of lighter crank



Offline Foxx4Beaver

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Re: Differences between a 90 500 crank and a 02?
« Reply #4 on: January 04, 2015, 04:23:50 AM »
more good info.
Excuse me, ma'am...but you've got extremely nice legs!!!...what time do they open???                                                                                                               https://www.youtube.com/watch?v=n8tCgN3aryQ

Offline sandblaster

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Re: Differences between a 90 500 crank and a 02?
« Reply #5 on: January 04, 2015, 04:54:10 AM »
So much for prognostication  :lol:
I have some on this site saying the pre 91 cranks are lighter then the post 91.
So, the next time I get one I will weigh it so we can have proof one way or the other.
I'll start with the 92 and later since I have one on the shelf.
Unfortunately my scale only weighs by tenths of a lb so hopefully we will be able to see the difference, or not  :|
The four stroke engine: That's one stroke for producing power and three for wearing the engine out.

Offline zz3gmc

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Re: Differences between a 90 500 crank and a 02?
« Reply #6 on: January 04, 2015, 05:25:17 AM »
Thanks for the info!

Offline dave916

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Re: Differences between a 90 500 crank and a 02?
« Reply #7 on: January 05, 2015, 06:40:03 AM »
So much for prognostication  :lol:
I have some on this site saying the pre 91 cranks are lighter then the post 91.
So, the next time I get one I will weigh it so we can have proof one way or the other.
I'll start with the 92 and later since I have one on the shelf.
Unfortunately my scale only weighs by tenths of a lb so hopefully we will be able to see the difference, or not  :|


CRANKS   88on same weight  , Think the 87 is also the same
85/86 Heavier  {not sure by how much but a fair bit, alot more than a tenth of a lb}

Offline RoostiusMaximus

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Re: Differences between a 90 500 crank and a 02?
« Reply #8 on: January 06, 2015, 03:52:31 AM »
I'll scale some

Offline sandblaster

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Re: Differences between a 90 500 crank and a 02?
« Reply #9 on: January 06, 2015, 06:29:12 AM »
The four stroke engine: That's one stroke for producing power and three for wearing the engine out.

Offline sandblaster

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Re: Differences between a 90 500 crank and a 02?
« Reply #10 on: January 06, 2015, 06:47:36 AM »
92-04 KX500 Crank 9.45lb   (As close as my freight scale will get)
The four stroke engine: That's one stroke for producing power and three for wearing the engine out.

Offline dave916

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Re: Differences between a 90 500 crank and a 02?
« Reply #11 on: January 06, 2015, 08:22:44 AM »
92-04 KX500 Crank 9.45lb   (As close as my freight scale will get)

Crank Halfs   product/part no is the  same from 89/04 so there will be no differance     
I have weight the 88 and that is also the same89on,    {87 also looks similiar weight to the 88on  but i do not have one}
85/86 also have the same part numbers/ weight {heavier}  needs the wider pre 89 cases to fit in


Offline motopunk

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Re: Differences between a 90 500 crank and a 02?
« Reply #12 on: January 06, 2015, 03:56:19 PM »
92-04 KX500 Crank 9.45lb   (As close as my freight scale will get)

Crank Halfs   product/part no is the  same from 89/04 so there will be no differance     
I have weight the 88 and that is also the same89on,    {87 also looks similiar weight to the 88on  but i do not have one}
85/86 also have the same part numbers/ weight {heavier}  needs the wider pre 89 cases to fit in


  case halfs 83-85 are the same (also reed cage and clutch cover gasket) ...   86-87... 88 is a bastard cylinder similar to 86 and 87 but clutch and transmission shafts are like the 89 and up  and at least 89-2004  ... 
the cranks would work in all engines, because same bore, stroke and crankbearings.. but watch out 83/84 is aircooled and has no gear for the waterpump ...  83-88 is the primary gear mounted with a big woodruff key . 89-2004 is a splined shaft on the right side..  83-91 are similar weighted cranks ...  92-2004 is heavier weighted for more torque in offroad use (same reason for the changed ignition with the big flywheel)  .
big 2 stroke bikes are weapons for real men, who don´t fear death or devil. ;O)
´83 kx250, ´87 kx250 (with 360 big bore), 87 kx500, ´93 kx500 sfc

---  www.der-motopunk.de.tl  ---

Offline dave916

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Re: Differences between a 90 500 crank and a 02?
« Reply #13 on: January 06, 2015, 10:57:10 PM »
92-04 KX500 Crank 9.45lb   (As close as my freight scale will get)

Crank Halfs   product/part no is the  same from 89/04 so there will be no differance     
I have weight the 88 and that is also the same89on,    {87 also looks similiar weight to the 88on  but i do not have one}
85/86 also have the same part numbers/ weight {heavier}  needs the wider pre 89 cases to fit in


  case halfs 83-85 are the same (also reed cage and clutch cover gasket) ...   86-87... 88 is a bastard cylinder similar to 86 and 87 but clutch and transmission shafts are like the 89 and up  and at least 89-2004  ... 
the cranks would work in all engines, because same bore, stroke and crankbearings.. but watch out 83/84 is aircooled and has no gear for the waterpump ...  83-88 is the primary gear mounted with a big woodruff key . 89-2004 is a splined shaft on the right side..  83-91 are similar weighted cranks ...  92-2004 is heavier weighted for more torque in offroad use (same reason for the changed ignition with the big flywheel)  .

Most of motopunk information on cranks is INCORRRECT dont know where u are getting it  :-D
Correction below
83-87 is the primary gear mounted with a big woodruff key
88-2004 is a splined shaft on the right side  {circlip}
pre 87 are the heavy cranks
pre 87 cranks cannot be used on 89/cases even if u change the clutch and primary gear
lighter crank from87/88 till 2004 same weight

U Got to Think how are they going to make the crank heavier in 92 without  modifing the cases{please dont show me a works crank}  :-)

Offline motopunk

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Re: Differences between a 90 500 crank and a 02?
« Reply #14 on: January 07, 2015, 04:35:57 AM »
my infos come from my kawasaki dealer, here from the site, and there:  http://www.cmsnl.com/kawasaki-kx500_model11963/ and if you know how to use google or another searching mashine, you find a lot more facts about the big green beast...

 so you say my infos are incorrect?? i have to say, you have to do your home work much better !!
 i dont spoke of the circlips on the crankshafts because i thought you know what we talk about here...  :-P

 if you change the cranks you always need the primary gear from the same years like the crank (only diference in the gears is the mounting to the shaft)
  the heavier crank came in 92 because of the most people that used it for offroad and to bring more torque to the powerband in addition with the bigger statorplate and flywheel..
 83-91 cranks have holes, that the 92-2004 dont have... 
change in the cases is for the evolution of the powervalves 83-85 no powervalve, 86-88 has 2 vertical powervalves = 2 holes in the cases for the valve-shafts, 89-2004 became the mainvalve added ,so that are now 3 valves in and 3 holes in the crankcases ....83-88 have also a shorter second gear , that would changed in 89 (i have the newer longer second gear in my 86 kx500 engine) all other gears and shiftforks are also the same parts 83-2004 only the shafts would changed for another splining in the clutch hub . 83-87 have also different mounting for the countershaft-sprocket  (big nut)  88-2004 with circlip...

why you think the cases would be changed for a heavier weighted crank?? from where comes your knowledge??

  its the same part numbers 89-2004 only real difference between 86-2004 is the change of the clutch actuation in 88 and the 3rd hole for the exhaust valve since 89...  last week i had a 2002 motor on the bench for replacing some damaged transmission parts... so it was side by side with my 88 engine...  i have also complete 88 and 86 transmissions in spare and i know each screw on my bikes. 

now you again dave...  :wink: maybe do you want also share some knowledge about the kx250´s ??

and question: what year kx500 is this on the picture ??

now i´m excited for the answer  8-)


big 2 stroke bikes are weapons for real men, who don´t fear death or devil. ;O)
´83 kx250, ´87 kx250 (with 360 big bore), 87 kx500, ´93 kx500 sfc

---  www.der-motopunk.de.tl  ---