could removing the airbox lid cause the top end to not get enough oil this is the story i am getting form the shop i took it to i am not gonna mention any names but he said by removing the airbox lid caused the top end to run dry and it always had oil cuold it be the oil pump
warreanty is out so its out of pocket now
i was just curious
Full Version: Yfz 450
I think the mechanic meant run lean. If you increase the air into the engine you also must increase the fuel. This causes the engine to run lean. The combustion temps go sky high and start melting important parts ( pistons, valves, rings). The fuel actually cools the chamber. Chances are you melted the piston and it needs a rebuild depending on how long you rode it. You might of warped a valve from the heat also.
this is MAINEVENT
I did rejet along with removing the airbox lid i am going to ask him if maybe the oil pump is F'ed up cause i rejetted the carb when i did some other mods inlcluding the baffle, and cam mod, with the airbox lid i forget what jet i bumbed upto
I did rejet along with removing the airbox lid i am going to ask him if maybe the oil pump is F'ed up cause i rejetted the carb when i did some other mods inlcluding the baffle, and cam mod, with the airbox lid i forget what jet i bumbed upto
I don't even run an airbox, and mine is fine. What exactly is happening. Maybe I can point you in the right direction. The airbox has absolutely nothing to do with the oil though. And doesn't effect the oil either.
well i took the bike in cause their was a loud clacking noise on my 2nd gear (Only) after my last trip to dumont so i take it in and today i called and they said they tore everything apart and my tranny is worked a tooth broke off on my second gear which F'ed the others from clanging around in their, and that my top end is shot due to lack of oil which i dont understand cause everytime i take it out i check for oil and its full and he asked if i have a airbox lid cause that was the cause of my top end going out i will talk to him some more later but i claim BS on the airbox thing 
so now i am looking at 1600 to 2000 dollars in repairs
so now i am looking at 1600 to 2000 dollars in repairs
I think LOTS of people have added pipes, K&N filters, and removed their airbox lids and NEVER rejetted, and although you definitely wouldn't get all the power out of it that you could, I've never heard of a top end cooking because of it.
Seems like crapola to me.
Seems like crapola to me.
| QUOTE (az350x @ Jan 21 2005, 04:18 PM) |
| I think LOTS of people have added pipes, K&N filters, and removed their airbox lids and NEVER rejetted, and although you definitely wouldn't get all the power out of it that you could, I've never heard of a top end cooking because of it. Seems like crapola to me. |
As far as I know, if you've done all that then you better rejet.
| QUOTE (az350x @ Jan 21 2005, 04:18 PM) |
| I think LOTS of people have added pipes, K&N filters, and removed their airbox lids and NEVER rejetted, and although you definitely wouldn't get all the power out of it that you could, I've never heard of a top end cooking because of it. Seems like crapola to me. |
I cannot stress this enough...The YFZ are super lean from the factory. They do it to pass CA emissions. Being so lean in stock form, if you take the airbox lid off, you are going to cook your motor. Not having the right air/fuel mixture is what leads to this. Have you ever started a yfz in the dark, and wathced the headpipe turn cherry red? Well that is what is happening inside as well. My bike is jetted probably as close to perfect for my setup as I can get without a dyno. My headpipe does not glow, and my fan doesn't come on.
As far as the oil problem, jetting has nothing to do with oil getting to the head. Your dealer is a nut job. It is definatly an oil problem, but I'd say it is from a faled oil pump. or a severely clogged oil filter. There is always a chance that you could of just gotten a bad bike, but either way I would call your yamaha rep and I bet if you tell him you are getting jerked around they will cover at least some of your repairs under warranty.
Just got a call he said he check the oil pump its good he said its from lack of oil change i have changed the oil twice and have only probably rode it 4 to 5times max this is BS 
some of the items he mentioned were cam is trashed valve are done and top end is shot and a the tranny of course and the cost for the repairs
$1973.49
some of the items he mentioned were cam is trashed valve are done and top end is shot and a the tranny of course and the cost for the repairs $1973.49
| QUOTE (desertbound @ Jan 21 2005, 05:46 PM) |
| My headpipe does not glow |
Liar liar pants on fire. You just don't ride it enough at night to see it.
As for the original post, sounds like the shop is taking you for a walk in the park. Go to the shop, and take a look at the parts, then call me, and let me know what you see. I can help you. PM me for my number.
The mechanic is wrong about your air box lid. Being a four stroke, oil is pumped through the engine regardless of how lean or rich the bike runs. Two strokes rely on the fuel/oil mixture to lubricate the engine but not four strokes.
leaning the bike out could cause the piston to crack, melt, hole, or weld to the cylinder. Your cams would still be fine though. Did you clean the oil strainer and change the oil filter? Plugged strainers and or filters could stop the oil from reaching the head.
I would pick up all your parts and have another shop give you a second opinion. You are getting incorrect information from the shop, no doubt about it.
How did the bike run when your had the problem with the transmission?
leaning the bike out could cause the piston to crack, melt, hole, or weld to the cylinder. Your cams would still be fine though. Did you clean the oil strainer and change the oil filter? Plugged strainers and or filters could stop the oil from reaching the head.
I would pick up all your parts and have another shop give you a second opinion. You are getting incorrect information from the shop, no doubt about it.
How did the bike run when your had the problem with the transmission?
| QUOTE (Fireballsocal @ Jan 21 2005, 07:42 PM) |
| The mechanic is wrong about your air box lid. Being a four stroke, oil is pumped through the engine regardless of how lean or rich the bike runs. Two strokes rely on the fuel/oil mixture to lubricate the engine but not four strokes. leaning the bike out could cause the piston to crack, melt, hole, or weld to the cylinder. Your cams would still be fine though. Did you clean the oil strainer and change the oil filter? Plugged strainers and or filters could stop the oil from reaching the head. I would pick up all your parts and have another shop give you a second opinion. You are getting incorrect information from the shop, no doubt about it. How did the bike run when your had the problem with the transmission? |
go pick your quad up right now!!! that mechanic has his head in his a$$
when i first started reading this post...i thought u maybe had a 2stroke! if you have a YFZ...thats no mechaninc your dealin with...he is a loon!!! he has no clue what he is doing!!!
what fireball said is all true...
get your quad outa there now!!!!
| QUOTE (az350x @ Jan 21 2005, 05:18 PM) |
| I think LOTS of people have added pipes, K&N filters, and removed their airbox lids and NEVER rejetted, and although you definitely wouldn't get all the power out of it that you could, I've never heard of a top end cooking because of it. Seems like crapola to me. |
Okay, I should have clarified, I was talking about 4-strokes in general (adding pipes, etc.). I have no experience with YFZ's, and had no idea they jet them lean for CA emissions.
I still agree with everyone else here though- your mechanic is either an idiot, or he's assuming you are.
As a girl.... my question to you guys is...this shop came recommended and that is why he brought it there....so any suggestions on a good shop in 818 or surrounding area? Just asking. Colleen 
| QUOTE (24v @ Jan 21 2005, 05:36 PM) | ||
Liar liar pants on fire. You just don't ride it enough at night to see it. As for the original post, sounds like the shop is taking you for a walk in the park. Go to the shop, and take a look at the parts, then call me, and let me know what you see. I can help you. PM me for my number. |
Of course it will glow if I let it idle for a couple minutes. But not like it did when it wasn't jetted correctly. And under normal riding conditions it doesn't glow. Racing the hill it does a little. That is just the nature of the beast. The true problem is when you can see it glowing in daylight, or if it is cherry red while riding at normal speeds. It could also be because my pipe is ceramic coated and it disapates heat a lot better, but generally your headpipe should not be bright as hell under normal riding conditions.
I'm sure it will glow more after I get that big mugger in the cylinder as well.
| QUOTE (24v @ Jan 21 2005, 05:36 PM) | ||
Liar liar pants on fire. You just don't ride it enough at night to see it. As for the original post, sounds like the shop is taking you for a walk in the park. Go to the shop, and take a look at the parts, then call me, and let me know what you see. I can help you. PM me for my number. |
Same here bud. PM me with any questions.I am not as experianced as 24V, but I can help also.
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