Finally the search is over...new 450f acquired!

[thefickler]

Hey guys. Well I finally was able to score a bike, and seal the deal. I picked up this '07 last weekend, and can't wait to get out and see how she does! Im finally getting back into the riding scene, and I have always has 2-strokes until now...and riding this bike, is pretty sweet ? .

Plan on doin the oil change, and greasing all of the bearings etc. this weekend before I really start to ride it. I'm also going to check the valves and make sure they're ok as well. Is there anything else I should be paying attention to right now as well?

Needless to say, i'm pretty excited, and can't wait to get out and ride. Here are some pics of the bike, and also a quick walk around vid. I like the note she's got. Also, Rob was the original owner I guess...and the guy I bought it from never took off the name lol.

http://imageshack.us/g/685/rszp4290223.jpg/

[Gunner354]

That bike looks pretty new. No need to check the valves. They last forever unlike other brands.

[RiderX]

That bike looks pretty new. No need to check the valves. They last forever unlike other brands.

By checking the valves he means checking the valve clearance, and he is smart to do this. I always check them after about 10 hours on a new bike, then every 30-50 afterwards.

[yz450fcranker]

replace steering stem bearings to the newer steering stem bearings if you have steering stem bearing problems the newer ones that replace the old style come with a seal on the upper bearing to water proof it

[thefickler]

THanks for the feedback, i'll be sure to change out those bearings if they are in rough shape. She looks and felt pretty clean and in good shape to me, lets hope she isn't a bucket -o- problems!! I think I will learn a lot this weekend after a few rides.

[idahoexcr500]

Looks in great shape! I also have a white 07 bought a couple of years ago. A few suggestions based on my experience and reading the forums.

• Reroute the crankcase breather into the airbox.
  
• Full Skidplate
  
• Replace timing chain
  
• Take the time to dial in the suspension (sag and clickers). I run 95mm of sag and its been a good comprimise for turning and stability.
  
• Be careful when changing the oil with the lower oil filter bolt threads.
  
• As others have said, grease everything
  
• I replaced the chain guide that goes around the front of the swingarm and siliconed it to the swingarm. The chain is very quiet now.
  
• Oil - I run Yamalube semisynthetic as the bike shifts better with it than full synthetics. Lots of opinions on what oil to run.
  
• Adjustable fuel screw is nice to have
  
• I have stock gearing and its been ok, even in the mountains but one or 2 teeth lower would help if thats the primary type of riding you do.
  

Hope this helps

[MotoNatz88]

Great pick up! Bike looks like new! Glad to have you riding team Yamaha cuz!

Make sure you clean that bike and keep it looking and feeling new. Clean and grease those bearings!

[thefickler]

Thanks for the tips Idaho, do you have a pic of the chainguard move that you made? Maybe I can just search for that here on TT.

Also what is the reason for re-routing the breather back into the airbox? I have always been into hot rods, and I always just vented breathers to atmosphere, since I always wanted fresh air to go into the engine. Thanks for the insight.

And thanks cuz, the weekend can't get here fast enough...I need to start my love affair with that 4 stroke

[grayracer513]

...what is the reason for re-routing the breather back into the airbox? I have always been into hot rods, and I always just vented breathers to atmosphere, since I always wanted fresh air to go into the engine.

I don't reroute mine, and as a desert racer, I haven't had any trouble with it. But there is a potential for the breather to slurp fine sand or water into the engine under the right (wrong?) circumstances. While running, the reversion of pressure from the crankcase occurs too rapidly for this to happen, but if the end of the breather tube is under water or stuck in mud or sand as the engine comes to a stop, or while attempting a restart, the vacuum created by the piston upstroke could draw stuff up into the engine.

The bikes I have rerouted were done by placing a T in the existing breather near the cam box and leaving the OEM tube in place. Then a second line is run from the T to the air box, with a small filter on it. The second line breaks the vacuum that forms in the lower leg as it tries to raise dust or water by providing a secondary path of lower resistance.

replace steering stem bearings to the newer steering stem bearings if you have steering stem bearing problems the newer ones that replace the old style come with a seal on the upper bearing to water proof it

The original bearings are the same as all YZ/YZF models going back several years, and they were never a problem until the aluminum frame. The trouble is that Yamaha used the same top cover/seal as with the steel models, and it doesn't work very well against water. The revised upper bearing will have a seal built in to help with that. It's effective, but use a marine rated grease, and avoid spraying water on the seal.

By checking the valves he means checking the valve clearance, and he is smart to do this. I always check them after about 10 hours on a new bike, then every 30-50 afterwards.

Good advice. You never know what you have with a new used bike until you take a look. Change the timing chain annually, also.

• Be careful when changing the oil with the lower oil filter bolt threads.
  
• I replaced the chain guide that goes around the front of the swingarm and siliconed it to the swingarm. The chain is very quiet now.
  
• Oil - I run Yamalube semisynthetic as the bike shifts better with it than full synthetics. Lots of opinions on what oil to run.
  

Regarding the chain slider, I think the poster above was looking to quiet the chain slap that occurs at low RPM under a load. I was more concerned with the wear that happens when sand gets under it:

https://www.thumpertalk.com/topic/946340-picture-of-chain-slider-wear-to-swing-arm/

Regarding the lower oil filter cover bolt, here is the problem, followed by the simple cure for it:

http://www.thumperta...ad.php?t=575367

http://www.thumperta...ad.php?t=634724

On oil, I've heard just as many people claim the bike shifts better with a full synthetic as the other way around, and if you ask me, that whole thing is all in one's head. I run nothing but motorcycle specific synthetics in mine, and have for years. There are more important things than shifting in any case.

Download a manual:

http://www.yamaha-mo...uals/index.aspx

http://www.yamahaown...ook.com.au/?r=0

And since this is both your first 4T and your first YZF read up on this:

http://www.thumperta...ad.php?t=852961

Enjoy

[thefickler]

Hey thanks for the info Gray. Thats some great information, and a good place to start.

I did just come upon some troubling information though...skimming through my manual, I was reading up on the valve adjustments and I came across this drawing. Clearly if this is right, my valves have already been shimmed, or will need to be shimmed...

I had a huge worry before pulling the trigger on a used 4-stroke, and the seller said that he checked them last year with a buddy who has had a 4-stroke for awhile now, and they measured within spec...Wish I would have looked through this manual first before I bought it!

We'll see what the weekend brings when I can get a measurement and see where they are. ?

http://img109.imageshack.us/img109/2817/0502122210.jpg

[gscx]

Ok? If they do need to be replaced then just go ahead and spend the 500 dollars to replace everything, then never have to worry about it again?

[RiderX]

Ok? If they do need to be replaced then just go ahead and spend the 500 dollars to replace everything, then never have to worry about it again?

WT F, just because your valves need to be shimmed does not mean you need to replace them.

I had to shim mine after buying my bike used. My bike had very low hours (<50) and were probably never checked by the first owner. Mine had the middle intake valve, and both exhaust valves slightly tight.

OP, just check them and see where they are at and adjust if needed. Check them after another 20 hours or so, and if they get tighter, then you might have a reason to be concerned. You probably won't need to touch them. Also keep in mind Yamaha sets the clearence at the lowest possible end of the adjustment range at the factory (Intakes: .10mm on the intake and .20 on the exhaust), so it's not unthinkable that the clearance might get a bit below spec after a few heat cycles.

Edited May 3, 2012 by RiderX

[grayracer513]

Let's start by taking a deep breath and letting it out slowly, then take another look at those numbers. Every one of those valves is in specifications. The numbers are in inches.

The range should be:

Exhausts: .20-.25mm (.008-.010")

Intakes: .10-.15mm (.004-.006")

There, feel better?

Now, check the valves like you planned to, record your findings, and come back to them in 10-20 hours to see if they've moved. Another thing you can do to set yourself at ease is to take a look at what shims are in there now. If you find that most of them are odd sizes that don't end in a "0" or a "5", those are factory shims, and that usually means it's never been adjusted.

Only when you have to go more than .10mm smaller than the original shim, or find that you have to reshim within 5 hours after you last did do your valves need replacement.

[gscx]

WT F, just because your valves need to be shimmed does not mean you need to replace them.

I had to shim mine after buying my bike used. My bike had very low hours (<50) and were probably never checked by the first owner. Mine had the middle intake valve, and both exhaust valves slightly tight.

OP, just check them and see where they are at and adjust if needed. Check them after another 20 hours or so, and if they get tighter, then you might have a reason to be concerned. You probably won't need to touch them. Also keep in mind Yamaha sets the clearence at the lowest possible end of the adjustment range at the factory (Intakes: .10mm on the intake and .20 on the exhaust), so it's not unthinkable that the clearance might get a bit below spec after a few heat cycles.

Not saying he had to replace them, thats why i said " If they need to be replaced". I guess im just getting a little annoyed when people buy a 6 year old dirtbike and expect to not have to do anything to it, and then just ride it forever with no problems.

[thefickler]

I'm not saying that I have any problem doing any work to it. It is 6 years old....it will need work, yup got it. I've had a wrench in my hand for the greater part of my life, so im fine with a little wrench time. And I know i'll have to adjust valves, rebuild heads, etc. and I'm ok with that. If I'm not, then I should've been looking at a yz250. I only pointed this out since it was written in the manual in the valve section, and I could have brought it up at the time I was looking at the bike, rather than after the fact.

Thanks for the info though guys, I'll do some searches today to see if there are any little things I need to be aware of before I get in there. We'll see what the weekend tells.

Either way, it needs adjusting? Fine. It doesn't? Fine. Just means I will have other area's to clean-up and take care of before a ride and have a better running bike.

[559stan]

I bought the same low hour 2007 as you two months ago and really like it.

[thefickler]

Nice job Stan! I really like this bike so far too, just need to get my maint. done this weekend. Its Friday and its hard to concentrate at work. lol, all I can think about it getting my hands dirty when I get home today.

[thefickler]

Well was able to check the valves this weekend, and some good news...they were all in spec. Awesome, not sure if they have ever been changed or not, but I will check them again in the fall. I made sure to check them twice, as the gauges I was using could have their width shortened a bit as they were close to being too wide. I did however run into another issue while I had the valve cover off...

I had sand......inside the head from the breather tube. There was a decent amount in the spark plug area in the head, and the allen key bolt that is located directly underneath the breather port was packed full of sand. Does this seem pretty common if someone has had their bike in dunes, without the breather tube mod? The guy I got this bike from said that he had taken it to the dunes a few times...so I'm really unsure of how much sand is actually in the motor, and how long has it been in there.

I also started leaking some oil from the cam chain tensioner, so hopefully thats just a gasket.

I already am making up the breather tube mod so I can get it installed this weekend, but just really concerns me on how much damage this sand can/will do. Thanks for any insight guys,

[559stan]

I had a steering damper installed last week and when they pulled the steering head bearings they were junk. I had already told them to replace the bearings. Even these low hour bikes need the mod. Nice to have thumper talk so we all know the real deal !!!

[grayracer513]

Does this seem pretty common if someone has had their bike in dunes, without the breather tube mod? The guy I got this bike from said that he had taken it to the dunes a few times...so I'm really unsure of how much sand is actually in the motor, and how long has it been in there.

I also started leaking some oil from the cam chain tensioner, so hopefully thats just a gasket.

It can happen if the rider has a habit of stopping on the crest of a dune with the bottom of the frame sitting right in the sand and then either shuts it off or restarts it like that. It's pretty easy to avoid doing if you're conscious of it, but you could hypothetically get into a situation where something like that was unavoidable.

The really big danger is to the main bearings, since they are oiled by splash and drain back oil. Next problem would be the oil pump. If you want to dig into the matter just a little, next time you drain the oil you can remove the stator housing/flywheel cover. With that off, there is a port below and to the rear of the flywheel that will allow you look at the oil screen in the sump and the area under it to some degree. With the oil drained you can use swabs, etc., to find and remove any sand that may have gathered there. Of course, you'll want to watch for it in the oil filter, too.

The oil leak at the tensioner could be a gasket, but it also may be that the inner one of the two bolts holding it to the cylinder didn't get the copper washer it's supposed to have. On '06 and later models the hole for the inner tensioner bolt intersects an oil passage running to the cams, and oil can run around the threads and out under the bolt head without that washer, or if the bolt is loose.