what are valve guides.. im new at this stuff... but i found a 02 250ex for sale for like 300$ an i guess it needs valve guides.. what are those an how much do they cost?? an how much do u think the fix will be with labor???

 

Valve guides are what the valve stem is held in place with and a tube to center the valve on the valve seat.
Most quad and bike engine heads are made out of aluminum. Valves are made out of steel. If you made the valve stems ride up and down in aluminum guides with no pressurized oil they would not last very long. This being the case they are usually made out of things like a bronze or brass alloy.
They are very cheap. A few bucks apiece or so. The problem is, you have to do a valve job after new guides are pressed in. This is what cost the money. Just a guess but around 70 to 100 bones if you take the guy the head.

 

Valve guides a few bucks my butt, you better price them. By the way is the engine torn apart, if not how does the guy think there bad. I have rebuilt 2 honda engines and both were mid 80 engines and both heads had great valve guides. The guides are steel and do not wear out too often. You can talk to a shop and they will tell ya the same. Not trying to burst any bubbles here but I would say the person is saying this because they don't really know. Because I can tell ya this for a fact, if the guides are bad so are the valves and prob every other componant in that head. I would check into this a little further because this could end costing aroung $500-$700 if you fix it. But if the quad is in good shape than go for it because that quad is prob still worth $1500. I do have a set of 250x guides that I bought before rebuilding my 250x, and this is when I found out what I know, and mine did'nt need them. They were $13.00 a piece and I have 4, wich you only need 2 I believe. I will check and see if they will work for ya but I would think that they might, if that is all you would need then thank heavens. I would give them to ya cheap if they will work. But if they won't then expect to pay about the same for ones that will. I hope this helps you out in your choice. RUSS Sorry doc I did'nt mean to step on any toes here, just stating what prob is bad.

 

What you need to do is get it, take everything off sell it , but keep the chassis, and modify it,put a 400ex mototr with an extened swing arm thats chain driven, extened a-arms, and fully modded everything that would be cool.

 

No offence taken rfwlll.
I have no doubt that Honda wants a lot for their guides. When I need guides I go aftermarket and match them up to what I need. They are cheap that way and I get a better quality guide.
I agree with you saying that this "could" cost a bunch more. My friend has 2 honda 3 wheelers (I think 200's) and he claims that both have bad heads. I don't know if he was talking about cam surfaces or what but he said it was unfixable. They are sitting out in the rain right now.
So ya, this could be more than sdombek04 is bargining for.