09 yz450 won't start in gear

What the shop recommends in any case may or may not be what Yamaha recommends, and the former should always be taken with a grain of salt.  I have never used anything other than 10w-40 in any of mine except during the 3-4 hottest months of the year, when I use a 20w-50.  It makes no difference, however, the bike is generally unwilling to start in gear with either one. 

I too, for pretty much the last 40 years anyway, have ONLY used 10W-40, almost always either Valvoline or Penzoil in every bike I have ever owned.

The shop I am referring to is strictly a Yamaha Shop and I believe it is one of the oldest ones in existence in the US. I bought my FIRST brand new motor scooter there in 1973! A 175!

They are the ones who told me Yamaha had quit making the 20W-40 and said Yamaha now recommends the 20W-50. I pretty much take EVERYTHING any shop tells me with a grain of salt! This shop seems to be pretty good though, I do not think they have ever given me any bad information or advice. Course I know and have ridden with the owners sons who are now the owners.

I tried the recommended Yamaha Brand oil as I was tired of the constant pulling by this motor/tranny when in gear. Well that and not being able to start it when in gear, and especially as it was easier to kill the motor to find neutral than to find it with the motor running if you were not still rolling. That thicker Yamaha brand oil did not make much of a difference, but it was in there so I figured it would go the distance till the next oil change, which it did.

It was a noticeable improvement going back to a lighter/fresher oil last week, but still sometimes does not like to re-light if stalled. Kind of aggravating when in a more technical section and you would just like to be able to pull in the clutch, hit the button, and get going again. All the things and time I did/spent on it last year you would think it would be perfect by now! Guess it gives me something else to work on....like I need that.

The thing that made me first start trying all the different things on it was I noticed sometimes blipping the throttle or holding the RPM a little higher in gear with clutch pulled in, would allow me to find neutral....sometimes. You could also feel the forward pull lessen if you raised the RPM while sitting in gear. This made me reason it had something to do with the oil in the clutch and between the plates, or the way it was or was not circulating.

It IS better, but no where NEAR as nice as my old '99. Course that one does not have the button!

One of the things that you don't appear to be understanding is that a 20w-50 IS NOT thicker than a 10w-50.  At least, not at operating temperatures of 160 ℉ or more.  At that temperature, they are both 50 weights, and although SAE 50 is a range of viscosity, they are both about the same when warmed up.  The 10w-50 is only thinner when cold.


Some oil formulations do have more fluid drag than others, even in the same weight, but the viscosity, and certainly the cold viscosity, is not directly responsible.


Incidentally, YamaLube used to be made by Torco, but as of a couple years back, they have a new vendor.  I forget who it is, but one thing I never do is buy oil branded the same as any line of vehicles.

No, I do have a pretty good understanding of motor oils, as well as machining oils, and even various equipment oils as well.

I do understand that the first number is the weight of the oil when cold and then the second number is the weight once at operating temperatures. What I DO NOT understand is how they pull that trick off and make that work?! Technology! Some of it you just have to accept!

When I bought two quarts of Yamalube last year I think it was the first time since back in the seventies that I ran a manufacturers oil, and even back then I ONLY did that once or twice since even then it was about twice the price of Penzoil. Just wanted to make sure there was not an "easy" fix" to my clutch issues back before I went and tore into it so I tried the Yamalube.

I bet I have also argued with different folks maybe twenty times as so many people believe you CANNOT run Valvoline or Penzoil or pretty much ANY other brands of oil in motorcycles. As long as you know, read, and follow, the manufacturers information and do not run an oil with the wrong modifiers they work fine.

It does not surprise me about Yamalube being made by Torco...didn't they used to make that Blendzall as well? Back when I first started racing in the 70's I LOVED to ride behind somebody running that as the smell of that oil was wonderful! HA! In fact, I believe most manufacturers do not make their own "Name Brand" oils.

I do believe the problems we and others all have with some of these Yamaha clutches IS a problem related to fluid drag because of the way it effects the clutch operation, and how these problems show up. Weird thing is how not all the same years and models seem to have them, which sort of leads me to think it might also be a function of fluid drag combined with the buildup of tolerances within each individual clutch, or some of the other parts the oil flows though to get to them. (In my case like those six small oil supply holes on the backside of the clutch boss. I do believe THAT was limiting some of the oil supply into the boss.)

The YZ's do not have that judder ring in the clutch pack and when I added the additional clutch plates and pulled it out I thought for sure I had the problem fixed....till I rode in a rainstorm the next ride out and THEN the bike became wild upon clutch actuation in the wet. I could actually feel it pulsing or juddering as I would clutch to get better traction on the wet steep grass covered hills.

After all the work and changes I did to mine last year it seemed darn near perfect but over the course of last years rides as the oil got old or tired, it slowly seemed to start dragging a little more as it got harder to start when in gear, and the last few rides I even noticed I would have to blip the throttle once stopped in gear to be able to locate neutral. That was unnecessary till the last few rides. That little inconvenience is gone once again now that I have changed out the oil.

I typically run oil for about 1500-2000 miles. THAT is a lot considering most of what we ride is tight technical 2nd and 3rd gear single track with LOTS of slow speed first gear stuff thrown in.

I think the biggest gains I made were when I added those three new holes out near the front edge on the clutch because it seemed to me that the oil out there had no where to go when the clutch was pulled in. The centrifugal forces and continuing supply coming into the boss sort of kept those outer four clutch plates packed full of oil. Well at least that is what I saw it doing in my mind's eye. Could be wrong in my reasoning, but it was a definite improvement once they were added!

I know too the aftermarket clutches are not as contained and allow the oil to fling out real easily with more open outer clutch hubs, which does help them break the clutch pack free.

It still has a few minor issues, but way better than when I started. I keep saying I should tear into my '99 to see why it is such a wonderful clutch and has NONE of the issues as the '03.....but then I never do cause it is not broke!

FWIW my '09 YZ is the same way, even after replacing the clutch. The entire time I have had this bike I have had issues with the clutch feeling "sticky" or not want to disengage fully with the lever pulled in. I've just stopped trying to start it in gear.

Start it up put it in gear hold the clutch in turn it off then it should start in gear works on my 09 450 if I ever let the clutch out it want do it

Edited by springer8828

It seems to me that starting it and then shutting it off so you can restart it another way is kind of counterproductive, if not plain weird.

Dead engine race start where you want to be in gear.

It may seem that way but with dead engine starts everyone is constantly starting their engines as every line leaves so why not if it helps in on the starts

I suppose if that trick actually works, that would be a good place to apply it.   I may look into that for the next time, but I actually get off pretty near the front even kick starting in neutral vs. the rest of the field.  As long as it starts first kick, it's OK.  It would be better if in gear, though, yes.

Start it up put it in gear hold the clutch in turn it off then it should start in gear works on my 09 450 if I ever let the clutch out it want do it

You know in a weird way that sort of makes sense to me.

From all the clutch work I did to mine last year and what I think the problem is this just might help sort of explain it.

I believe a big part of the problem is that the stock clutch pack tends to hold or trap the oil in. Especially the oil located in the first 4-5 clutch plates. This would help explains why I had such great results once I added the three small holes in the inner boss behind those outer plates. These holes allow the oil to flow through that area better and easier. I think oil in that area can also sort of get cooked/thicker as it does not get a fresh new supply as easily as the rest of the clutch pack. These new multi viscosity oils do get thicker with heat too and what better place to get hot than inside a clutch pack?

By starting up the motor and putting it in gear, you pull in the clutch, which slightly opens up the gap between the clutch plates, and would allow some of the oil in there to spin out. Then you kill the motor and the clutch pack will be loose cause it is emptied out, or less full of oil than if the motor was killed with the clutch out and plates engaged. Then when you hit the button to re-start it has less resistance or clutch drag and would seem to make it light up easier.

This same thing, (I believe it is the drag from the oil across the clutch plates), explains why if you blip the throttle with the clutch in it is way easier to find neutral. On mine before I did all the work I could not even put it in gear without the brakes on as it would take off on me. Raising the speed of the motor helped some with that as it makes drag between the oil and plates less noticeable. You could actually feel this too by putting it in gear and then when you blipped the throttle the drag or forward pull would lessen up, but return as the motor came back to idle.

This would also explain why the Hinsen and aftermarket clutch baskets fix the problem. Because they are a LOT more open and the oil flows through them MUCH better.

Yea you can also tell by if you kill the motor with it in gear with the clutch in get off and push it it's easier than if it's in gear and you pull the clutch to move it you will have more resistant

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