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Going to look at a CRF250R today, what should I look for?

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I've been an ATV and motorcycle guy all my life so I can look for regular things, and judge it by how it looks and runs, but I've never owned a Honda motorcycle, and dont have time to research in depth because this is kind of a spur of the moment thing. I'm looking at it in about 4 hours.

When I go to look at it, are there any things SPECIFIC TO a 2004 Honda crf250r that I need to watch out for? Reading through the FAQ it seems like valves can be a problem, but this person states that the valves were "bent" and so he had the head reworked and kibblewhite SS valves installed and shimmed. Is that a proper fix?

here is the craigslist listing: http://stlouis.craig...2756180986.html

Thanks for any insight that I may not be aware of! Sorry for such a short notice, lol :smirk:

Edited by Joester

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The one thing that the ad does not state is exactly how many hours are on the new valves, or even more importantly how many hours on the bottom end (crank) and piston? He says that it's common for '04-'05 bikes to bend valves, NOT true! The '04's had a problem with wearing out valves/seats (most commonly the right intake valve) which required valve replacements. Something major has to happen inside the motor to bend a valve, most commonly caused by jumping time where the piston comes into contact with the valve. Stainless valves are fine for trail riding and Kibblewhite makes a good product.

Things to ask:

1. Exactly how many hours are on the bottom end and piston? If they hours are high, have they ever been replaced and if so what were they replaced with OEM or aftermarket (which brand)?

2. How many hours are on the new valves?

3. What caused the valves to bend?

4. How often do you change the air filter and engine/trans oil?

5. What type of riding did you do with the bike?

6. Clean title?

Hope this helps. :smirk:

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Yes, it definitely does help. I'll make sure to ask him if the valves actually bent or if they just went out of spec, along with the other questions.

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Stainless Steel intake valves are heavier thatn stock titanium ones and should only be used if the stock valve springs were also replaced with stiffer valve springs.

It is worth asking if the intake valve springs were also replaced.

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something came up for the guy and i will be looking at it sometime later, maybe this sunday. I will be able to do my own research now, but that doesnt mean you should stop with the tips! :smirk:

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carful with that.. if the valves were "bent" then that means they were hit by the piston. which also means you have a bent rod.. most dealers will go through a bike and check it out for 100 bucks.. is a good thing to do.. i bought my 06 crf250r it started fist kick cold when i was checking it out.. got it home and it wouldnt run at all.. turned out he ran the engine out of oil then put thick oil in and adjusted the valves.. so it would run good for about 15 minutes... $1200 rebuild..

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with the valve issue: are SS valves, head work, and new valve springs actually a FIX, or will the valves wear out just as quick as if they were stock valves?

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Stainless steel valves are more compatible with the powdered steel valve seats, can tolerate small amounts of dust getting into the engine better than titanium valves. and are thereby more durable. Actually, replacing titanium intake valves with stainless steel valves is an easy, economical fix. The only downside is stainless steel valves weigh more, require stiffer springs... and the stiffer springs and additional weight can reduce power up to 2hp. For offroad and trail riding, or for a practice bike that's going to get a lot of hours, the drop is hp is a reasonable trade-off for less maintenance and lower costs.

The stock titanium ones are softer than stainless steel and if a rider spent most of his/her time riding the rev limiter, the Ti valves would often cup a little over time and thus would settle a bit deeper into the valve seat, eliminating the required clearance between the top of the valve/shim/bucket and the cam. This settling/cupping distorts the valve face to seat seal causing compression loss and hard starting.

The high tech solution for titanium valves is making the valve seat out of more exotic Copper-Berylium (Cu-Be) alloys. Cu-Be is softer than powdered steel, and cushions the valve closure better and also conducts heat away from the valve into the seat and head much better. As a result, titanium valves (and even stainless steel) ones last longer and will actually run a few hundred degrees cooler. The downside to Cu-Be is the alloys are really expensive; each seat can cost $100 or more to install, and the metal alloy is also toxic to machine, so extra measures have to be put in place to work with the alloy. Cu-Be valve seats are standard practice for NASCAR, NHRA, Formula 1 and other super high-performance engine designs, but adds too much cost to an engine for manufacturers to offer stock.

Edited by Grinstead_77G

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