Stainless intake valves?

Just wanted to ask if anyone makes stainless intake valves for the WR? I'm thinking I may need to replace my intakes and wanted to go to stainless if possible. Thanks!

Can't answer your question, but how many miles do you have where you need to change valves? And why stainless?

My bike only has 7200 miles on it. I got it with 6700 on it and it had a weird issue with the right intake valve. It had no clearance left so I shimmed it and it ran great since then. It is now acting up like it did when I got it. I plan on doing a leak down test and then checking the valve clearance befor I tear it down. (compression test is about usles on these bikes) I would like to go with stainless intake valves because they last alot longer than the Titanium ones do in most bikes. I would like to do the job once and ride the heck out of it. Thanks for the reply!

The stock valves in these bikes are excellent so if you're having a problem with one, my guess would be either a defect or the PO was messing with things he didn't understand. Normal maintenance interval is 26,500 miles before you need to even adjust the valves - I just can't really imagine anything being an improvement over that!

stock intake valves are titanium , why change them? 

I have never been inside one of these motors before so if this doesn't apply please forgive me. On Toyotas that use shims for valve adjustment the shim sits in a bucket that rides right on top of the valve. They generally never need adjusting. Anyway there was an issue with some cars, that the bucket itself would wear / deform where it contacted the valve increasing clearance. So the fix was new buckets and re-shim.
Anyway like others are saying if your valves need adjusting every few thousand miles there is something defective. Could be valve, bucket, valve seat etc.

The previuos owner rode the bike till it had 6700 miles on it, then it would not start. I got it for only $1500 with all kinds of aftermarket goodness allready installed. The right intake valve lifter bucket had NO clearance at all. All the other valves were in perfect range. I have no idea what caused the problem. I replaced the lifter bucket and re-shimmed the valve and the bike ran great up untill now. I understand shim valves very well. I have owned 2 Toyota tacomas and a Tundra (both shim valves) and I have worked on several CRF's with shimmed valves. I am an ASE cetified tech with over 15 years of working on cars, motorcycles, boats, ect. I know on most CRF's with Ti valves there tends to be alot of wear on the valves and the cure is to use stainless. I have a post titled "What N' the hell" that has some more info on my bike and pics of the old lifter bucket. Thanks for the help!

Was there evidence of the engine having inhaled dirt?
Any word of or evidence of somebody lapping the valves?
 
Titanium valves are treated with a hard coating that, if it gets worn off, the valves are much shorter-lived.

It's probably just a case of somebody either not knowing what happened or not telling you what happened.

Chances are you will have to buy OEM valves for the WRR/X as theres no other option.

It doesnt have valve issues very often so no one makes stainless valves for it that I know of like they do the mx based 4 strokes that have valve issues often.

I don't believe it ever had dirt in the intake. The engine/frame was spotless when I got it. The guy rode it to work down in the Santa Cruise area. He said it ran fine until one day it just wouldn't start. Same thing it's doing now. Pretty sure it was never taken apart. The guy was a straight shooter, police sergeant. I guess there might be a lemon or two in the bunch every now & then. I did get the chance to ride it all summer so I'm more than willing to fix it again. Must be a bad valve issue. I'll keep everyone informed when I get a chance to diagnose & repair it.

I have a CRF250R that used to eat valves for breakfast, so I replaced them with stainless and never looked back. Same thing, would run fine up until the point where it wouldn't start.

As stated, there are very few reported problems with the stock valves on the WR, so if it is a bad valve (and all the symptoms indicate that it is), I would replace with stock OEM.

My guess is that if the PO ran it for a long time with no clearance on one of the exhaust valves, then that has allowed carbon to build up around the valve and seat. With the carbon buildup, the valve can't close, which gives you low/no compression.

I think you're looking at a valve job.

I have a low mileage head in good shape that I would part with if you don't want to mess with yours.

Thanks Bob! That's good to know. I might be interested in that used head. How many miles are on it, and any idea how much you'd like for it? I think mine is just a weird fluke.  Both the exh. valves were in perfect spec when I checked them. The only one out was the right intake. The bike is Super clean and was very well maintained. I only had 3% leakdown when I reshimmed the valve before so I'm hoping I might be able to just throw in a new valve & go. I'll have the seat & guide inspected while it's apart. I'm gonna start with a leakdown test when I get time. Keep ya posted!

Well, just got it torn apart and the right intake valve has no clearance what so ever. Not sure what caused it? At least I know what went wrong! Looks like I'll be buying that used head from you Mr. BuilderBob.

Got the head torn off last night. The right intake vale is worn down paper thin.  Not sure what the hell caused it. Now I need a little advise on how to go about fixing it. Should I buy another valve, throw it in and hope for the best? You can't lap Ti valves so that worries me a bit. The other 3 looked fine and are in spec. Should I mess with them at all?

Hey mate it's a tough call as there are several options you could take.

I suppose a major factor is if you plan on wanting to keep the bike for the long term ?
It seems as though your very capable of actually doing the "hands on" repairs, but it's still a matter of inconveniant down time + the cost of gaskets / parts / coolants etc.

Anyway as for the head at present, what does the actual valve seat & surface "look" like ? I suppose if it seems to appear ok in regards to surface condition & seat recession, then you might just get away with a new OME Ti valve.

If the price of the new valve is reasonable, then i suppose that you could just purchace one & then check it's initial fit up for seat angle etc. Then once properly fitted, un-lapped, you should get a good idea of any possible "un-seen" valve seat recession by comparison of seated position to the other "good" intake valve.

You can then do a valve seat leak test with CRC, or fluid of the like, into the combustion chamber / recess of the up-turned head. Spark plug fitted tight obviously. ( I'm sure you know what i'm talking about here for this valve leak test ). Anyway this should then give you a very good idea of where you are at prior to bolting the head etc back on, & possibly "wasting" a gasket set / coolant / time etc. If there is any negative or poor results at any stage of the above checks, then you can move onto other options, such as that second hand head from B/Bob. This may mean that you only "burn up" the cost of the one new valve.

In regards to sourcing another cylinder head, i have seen several for sale recently on AU Ebay, but all from USA sellers. ( So i'm sure that they will also be listed on US Ebay ). There was a "mint" one off a WRR with under 1000 miles on it yesterday but it's gone now ? Was a bit pricey though.

Anyway as an example i have supplied the below AU Ebay listing for a second hand head, price seems ok, but not sure of miles or condition. It was mostly the chick on the listing pic that initially caught my eye ! lol. ( Although she looks a little "pumped up" on the gas on a closer look, lol ) Also had a bit of a LOL at the dudes user name for that listing. Seems legit though on sales / feedback score.


http://www.ebay.com.au/itm/CYLINDER-HEAD-2009-Yamaha-WR250R-WR-250R-250X-Motor-Engine-Top-End-08-09-10-/110762231214?pt=Motorcycles_Parts_Accessories&hash=item19c9f185ae#ht_628wt_758

Cheers.

Just to add mate, i found that other "mint" head on AU Ebay that i was talking about in my above post. ( US seller ).

http://www.ebay.com.au/itm/Yamaha-WR250R-Head-Assembly-3-WR-250-R-250R-2008-MINT-/281046166440?pt=Motorcycles_Parts_Accessories&hash=item416fa82ba8#ht_2466wt_966


As i mentioned it's a bit steep on the "buy it now" price, but you can submit an offer. I actually just brought a rear shock assembly from this same seller recently. It's currently still in transit to me here in OZ, but he did take my offer - which was almost 20% less than his "buy it now" price.

I suppose for the very low mileage listed it would still be alot cheaper than a new head + all the "extra" stuff that is also included, such as rocker cover etc. In any case it all looks to be in very, very good condition in the photos.

Anyway the 2 examples shown above seem to cover both ends of the scale in condition & price. Maybe B/Bob's deal and head condition might land you somewhere in the middle ?

Cheers mate & keep us posted with any up-dates.

Personally, I'd have a guy who knows modern 4-stroke dirt bike cylinder heads listen to your story and take a look at the head and worn valve to get an opinion on the condition of the valve seat and ask his advice on a proper repair that will be reliable.

If you want any part of the supposed 26,000-miles-between-valve-clearance-checks this bike is known for, this has to be correct and I wouldn't just buy a new stock valve and throw it in and cross my fingers.

Thank you YZEtc and GT-250. Both of your responses are very helpfull. I think I'm gonna go with builder Bob's used head due to the fact that it will take alot more time and $ to fix the head I have now.  The seat looks pretty good, but I found that you really should have it re-machined when installing new valves. If that's the case then I'd want to do all 4.  The intake valves are about $85 a peice and trying to get machine work done right around my area is pretty tough.  I'd have to take it an hours drive away and wait who knows how long before it would get done.  I am a little worried why this happend to my current head also. If I replace the whole thing with a good used one, I might feel a little better about trusting it on longer rides. Just my weird theory. Keep ya posted. By the way GT-250, the head off of my bike is cleaner than the nice one listed on ebay, ha ha! I don't like to mess up my nice (dirt) bike.

When I redid the valves and head in my CRF, I shipped it to Dave: http://www.mxtime.com/

He is very well known on ThumperTalk and did a fantastic job. Just throw it in a box and send it to him. I sourced the new valves on eBay and sent him all the parts, he cut the seats and assembled and shipped it back for a very reasonable price.

I would be a little more concerned about the root cause of the valve wear. Do you think it is just a defective valve? Do you ride in really dusty or sandy conditions? Is your air filter doing its job?

Thanks for the info dmmcd. I'm gonna go with the used head that Builder Bob has for me. I think the problem is a defective valve. I don't ride in sandy conditions, previos owner may have. When I got the bike it was spotless everywhere. Very well maintained. I guess there has to be one lemon in the bunch once in a while. I got the bike cheap and got to put 1600 miles on it so far. Love it, worth the time to fix and enjoy it some more. Check out my post titled What N' the hell for some pics & info about when I first go it. Thanks again to everyone for the help and a huge Thanks to BuilderBob for hooking me up with a head! 

Sounds like Bob could be a good guy to know!  

^^ Can We Fix It ? ... YES WE CAN ?  

 

I got the new (used) head from Builder Bob today! Looks great! Gonna make my project a whole lot easier to get done quickly. Too bad I have a bunch of fresh snow on the ground. Kudos to Mr. Bob for helping me out. Great guy to deal with, glad I found him. Thanks again! 

No problem, Joe. Glad to help.