New guy from South East Michigan

Hello

I just picked up my first bike 1998 KX250 2Smoker :)
I rode a crotch rocket about 7-8 years ago for very short time and it was just too dangerous for my crazy self, so I had to get rid of it. I been wanting another bike for a long time so I decided something little less dangerous (I hope), I don't plan on doing anything crazy with this KX, just some trail riding in the Northern Michigan with some buddies.

Bike was somewhat rebuilt by the previews owner, it runs strong but he did tell me that the KIPS - exhaust valve system will need to be cleaned (starts to bog a little in the high power band) which is a bitch to get to, I have to pull the whole top end apart. I got two manuals for the bike and have read them both, watched bunch of you tube videos and been looking at these forums for past couple weeks trying to decide if I should take on the project my self or take it to the shop?
4
I am kind of jack of all trades but I have never worked on any bike. I was thinking about ordering a new WISECO piston and new gasket kit for the top end see where it takes me... What do the pros think?

Thank you

4
20130418_183059.jpg
 

SRAD97750

Moderator
Staff member
I love it! Welcome! Surf around and post up photos and video of you riding!
Do it yourself. Do everything yourself. You'll even thank yourself later...

It's having a hard time revving because of the stuck/dirty powervalve.
Disassembly is always free. You learn alot just taking it apart. Use the manual.
Post up if you have any questions, we're here 24/7...

Wiseco is a good brand and you can get their piston kits for cheap on ebay $80-160 Whole top end gasket sets for ~$20. You MUST change the piston pin bearing. It's not included in any of the kits. (unless specifically mentioned as included)
-BIG DAN:thumb:
 
Welcome aboard! Im afraid to say that you can wad yourself up as easily on your dirt scoot and you would have on your street scoot. But it all about how you manage what your doing. As for your power valve issue. I like your thinking about just redoing the top end. Ive purchased two used dirt bikes in the last 5 years. Both previous owners claimed that the pistons had low hours. The first one still had an OEM style single ring piston in it. And the cylinder needed to be related. My last bike (rather my current one) the previous owner said the same thing. He also lied to me about some other things he said that he had done. I found out quickly what had and had not been actually done. With that being said. I recommend you follow through and get yourself a new top end and gasket kit. Once youve got the cylinder off the power valve assembly is much easier to get to for removal cleaning and reassembly. Youve got a manual. Just do what the manual says and you'll be fine. Also while you have the motor apart, it might be a good idea to drain the gear box oil, take a peek at your clutch plates and friction plates. At a minimum take a good look at the oil or rather what may be in the oil. Your already gonna have it apart it doesnt take that much longer to do. And could possibly save you some work in the long run. A little tip on cleaning your power valve assembly when you get it apart. If the removable components inside are steel (and likely will be) and badly carboned up. Use some oven cleaner. It works great. DO NOT use oven cleaner on your aluminum parts like the cylinder or any plastic parts. It will damage them.

Thats about all I got. But Like Big Dan said if you get stuck or got a question. You could likely have a good informed answer with in 24 hours or less.
 
Welcome!

I'd start with a compression check, Check the reeds, Besure filter is clean, Repack the silencer, Clean the carb (Note down what jets are in it) ...And post as many pictures as you can take :smirk:
 
No point in a compression check in my opinion if you are getting a new piston. Inspect the nikasil bore for nicks and cracks. Clean the powervalve well. Check for play in the crank. Replace piston and wristpin bearing. Check for gaps in reeds, clean the entire carb and airfilter.
 
I changed all the fluids in it and the air filter. Muffler was fresh packed. I orderd new brake pads for front and back even thou they still lock up but I wanted a piece of mind. Pre owner claimed all that was new, but the air filter looked like shit and rear break pads are down to metal. Fork seals look pretty well, no dripat all. But I think he lied to me about few things. He told me that the piston is also new, I guess I wont know till I take it apart. I will still order brnad new Wiseco top end kit from cheapcycleparts.com (pk1293) It is $197.05 for everything. I think that is a decent deal for it? BIKE runs strong, I even had my buddies try it out that ride often and they said it was powerfull. I will post more photos later I am using my phone to post this, this site is blocked at my work. Damn Japs. :smirk:
 

James

Staff member
Welcome James! :cheers:

Dirt bikes can still be very dangerous, it's just up to you in how dangerous you want it to be. A plus is that unlike street bikes you don't have to watch out for the drivers/cars, which IMO is what makes street bikes so dangerous.

I should have joined your guys forum long time ago.
Well why didn't you? :smirk:
 
Welcome James! :cheers:

Dirt bikes can still be very dangerous, it's just up to you in how dangerous you want it to be. A plus is that unlike street bikes you don't have to watch out for the drivers/cars, which IMO is what makes street bikes so dangerous.


Well why didn't you? :smirk:

Like I said I am new in the dirt world so taking 1 step at a time :)
 
I love it! Welcome! Surf around and post up photos and video of you riding!
Do it yourself. Do everything yourself. You'll even thank yourself later...

It's having a hard time revving because of the stuck/dirty powervalve.
Disassembly is always free. You learn alot just taking it apart. Use the manual.
Post up if you have any questions, we're here 24/7...

Wiseco is a good brand and you can get their piston kits for cheap on ebay $80-160 Whole top end gasket sets for ~$20. You MUST change the piston pin bearing. It's not included in any of the kits. (unless specifically mentioned as included)
-BIG DAN:thumb:


You are right, I will do it on my own. All it is, is few nuts and bolts. Some good cleaning, new gaskets, some lube, some oil, some locktite and she ll be farting around the woods like a true queen I should have joined your guys forum long time ago.
 
Top