96 KX250 splitting cases

[Tonybeau]

First time I've gone to change the oil on my 96 KX250 and looks like the last owner messed the drain hole threads on the case.   Going to attempt to repair with a helicoil however think I'll remove the engine and split the cases to ensure its done right.

As I'm splitting the cases anyway I'm looking for advice on what else I should change whilst I'm in there such as gaskets, seals, bearings etc?

[Foxx4Beaver]

might as well replace every bearing and every seal...then go over the entire tranny, gears, shift forks, shift drum, shafts...replace anything that looks questionable.
buy all new snap rings too.
doing this now, could save you from having to do it later, and it will make it that much more of a reliable bike to ride.

[sandblaster]

might as well replace every bearing and every seal...then go over the entire tranny, gears, shift forks, shift drum, shafts...replace anything that looks questionable.
buy all new snap rings too.
doing this now, could save you from having to do it later, and it will make it that much more of a reliable bike to ride.

+1

[Tonybeau]

Thanks for the responses guys.  That's what I was thinking although was forgetting about the snap rings.

I take it its best to stick with OEM for the seals but what about bearings - are their any aftermarket bearings which are ok to use (and cheaper)?

[Foxx4Beaver]

you can use oem seals....Cometic makes crank seals specifically to help issues from E-10 in pump fuels...get Cometic gaskets also....best to just call them and place orders on the phone...

http://www.cometic.com/powersports-gaskets.aspx

I've gone next door to my local bearing shop a few times in the past, and had them make me up some bearings for far less money, but typically get oem if they're available.

[Tonybeau]

I'm going to order parts soon to do this.

Another couple of questions though.  I noticed when doing the top end that a previous owner installed a hot rods crank.  Reading this thread http://www.kxriders.com/forums/index.php/topic,15287.0.html it looks like the general opinion on these isn't good.  Do you think I should remove this and replace with OEM as don't really want to be tearing the engine down again too soon?

Also would a 98 OEM crank be ok in a 96 engine?  I know the part numbers differ slightly but I read that Kawasaki increased the crank weight to smooth out the bottom end (which I would prefer anyway) and I have also found new 98 cranks for around 30% less than the cost of the 96.

[sandblaster]

I would rebuild your crank using a Wossner rod kit.
Next OEM
Next Pro-X
The rods are the same for many years.
I believe 92-04 cranks will fit but ask Doldguy as he is a 250 guru...

[SOHC]

When you install a hellicoil into a kx it blocks off the small hole that lets the oil drain out of the bottom part of the case under the clutch

[Tonybeau]

I would rebuild your crank using a Wossner rod kit.
Next OEM
Next Pro-X
The rods are the same for many years.
I believe 92-04 cranks will fit but ask Doldguy as he is a 250 guru...

Thanks, I'll check into it.

When you install a hellicoil into a kx it blocks off the small hole that lets the oil drain out of the bottom part of the case under the clutch   

That doesn't sound good. Will this cause a running issue or just mean that when the oil is drained it won't drain everything.  Is there a better alternative that doesn't involve replacing the cases?

[Foxx4Beaver]

That doesn't sound good. Will this cause a running issue or just mean that when the oil is drained it won't drain everything.  Is there a better alternative that doesn't involve replacing the cases?

I installed a Helicoil in a '97 KX250's oil drain several years ago...very simple job, about 15mins. 
All you have to do is measure the depth, if I remember correctly, 10mm was good...then you want call Helicoil and order an M10 x 1.25 x 10mm stainless steel helicoil, and get a small bottle of Loctite 266, you'll be putting that on the outer threads of the helicoil just before you screw it into the case, then it will never move.

Time-Serts are another good way to go...but since the drain plug is such a low torque bolt, it's a bit overkill, and quite a bit more money.
I ran my '97 for 4 years with the helicoil...sold it to a buddy, who rode it for another 5 years without any issues. The key is to remember not to crank down on the bolt, just snug it up and safety wire it.