mxa says the 06 an 08 crf250 has severe bog issues. I never touched these stock bikes an neither never bogged once no matter if it was 105 degrees or 30 degrees outside. Both were really really fast as compared to my 10yzf250. This bike is a bogging machine. The slowest bike i have ever owned. It feels like the rear brake is dragging.. Almost comical! mxa said the 10 yzf250 has so much bottom and mid you need to regear it from 49 to 48 to mellow it out and make it more usable? I wonder if mxa really rode this bike? My bike has zero bottom- absolutely no mid and the top is a slow reving joke. Looking at the manuel it looks jetted alittle rich out of the box which should be good since its 30 degrees outside. I cant imagine going leaner? Starts and runs sweet on the stand. i have adjusted the fuel air screw every which way.. it runs like the ignition is retarded? I wonder if you can advance the ignition some like I could on my 2 stroke RM's? Has anybody exsperienced this slow feeling carb bogging syndrome with there 10 yzf250?

This message has been edited. Last edited by: TRA-742,

While I cant help you with fixing your steed, I can say that MXA is full of shit. Always has been always will be. I own a Yamaha, but I know to never look in there for honest info about Yamahas because I often refer to them as Yamacross action, that mag sucks and is totally biased!

I find that the dirtrider bike test to be the most acurate....

yes either this bike is ill or mxa is not at all acurate with bike tests. I also noticed after i loaded it up in the trailer- on the floor below the engine there was about a half dollar size of cream colored foamy oily gas smell stuff. Might of come out of the breather tube but it was not exactly under it? Maybe water pump seal? antifreeze looked clean and when i removed the oil filler plug no foamy stuff in there..

Ive had a few 4ts and have a bogging problem also I will list the problems
1. Plugged pilot jet
2. Fuel screw orifice plugged
3. accelerator pump out of spec or plugged
4. Throttle position sensor bad or not in spec.
5. intake valves tight also hard starting
6. cam timing on intake cam off
7. no oil
it really just sounds extremity lean richen pilot to 48 drop needle clip one

dont yamahas have a 30 day warranty?

quote:

Originally posted by TRA-742:
yes either this bike is ill or mxa is not at all acurate with bike tests. I also noticed after i loaded it up in the trailer- on the floor below the engine there was about a half dollar size of cream colored foamy oily gas smell stuff. Might of come out of the breather tube but it was not exactly under it? Maybe water pump seal? antifreeze looked clean and when i removed the oil filler plug no foamy stuff in there..

That little puddle of creamy looking oil is normal on the Yamaha's. I have owned 6 since 2006 and they all do that especially after a hard moto. The breather tube comes right off the top of the engine and drains down by the ignition cover. I believe Honda has theirs going into the air box which is why you dont see the puddles on theirs. Yamaha 250F's havent ever made the power that the Honda Suzuki and Kawi's make. We have stayed with them because they are so reliable. With how expensive racing is I cant afford to put a ton of money into repairing a rebuilding bikes and Yamaha though not the most powerful or best turning machines out there they seem to be the least expensive to maintain.

quote:

Originally posted by Vern#119:
dont yamahas have a 30 day warranty?

Yes they do and another reason I like the Yami's so well. I would take it back to them if you are still within the 30 days and tell them whats up.

Thanks for the info Vern. I will have all that checked out. I think i did hear about a yamaha 30 day warranty awhile back. I will be on that Tuesday. Good to hear its a durable bike and the creamy foam is normal thanks 216. It seems to handle stable like- yet can stick to the inside. Suspension feels good. No motor and bogging part sucks. I'm pretty sure my 03 yzf250 had alot more motor. Idk? maybe she's just a ten with a virus.

This message has been edited. Last edited by: TRA-742,

quote:

Originally posted by TRA-742:
Thanks for the info Vern. I will have all that checked out. I think i did hear about a yamaha 30 day warranty awhile back. I will be on that Tuesday. Good to hear its a durable bike and the creamy foam is normal thanks 216. It seems to handle stable like- yet can stick to the inside. Suspension feels good. No motor and bogging part sucks. I'm pretty sure my 03 yzf250 had alot more motor. Idk? maybe she's just a ten with a virus.

The bog you are getting is usually caused by the accelerator circuit. Mainly the large leak jet Yamaha continues to put in it(normally a #70-80). Not sure what size they went with in the 010 but if its not a #40-50 leak jet its too big. I also do the O-ring mod to the accelerator pump linkage. We have no bog issues with ours after doing these two things. Good luck.

Thats what it sounds like when it bogs- gurgling on to much fuel. I will forward this info to my tuner jps- hopefully he knows about the o-ring mod you do. thanks 216

quote:

Originally posted by TRA-742:
Thats what it sounds like when it bogs- gurgling on to much fuel. I will forward this info to my tuner jps- hopefully he knows about the o-ring mod you do. thanks 216

Actually it is usually too lean. the larger leak jet allows more fuel to go back to the float bowl and less into the engine. By going to a smaller leak jet it will actually give you more fuel on the initial twist of the throttle. The o-ring mod causes the accelerator pump to react faster on the fuel squirt giving the bike a quicker throttle response. The lean bog does "sound" like its too much fuel but it is normally the opposite its so lean the engine just stumbles and doesnt usually give the lean backfire you get from lean jetting. Ha ha I have been working on the YZ250F's since 06 and have become pretty familiar with how to get these carbs to respond really crisp. Practice makes perfect I guess. I think we are holding out for the 010 YZ450F and the 011 (hopefully fuel injected) YZ250F. Good luck man.

216 are you guys coming over in jan for the pasco arena-x? If I cant get it dialed in by then maybe i could hire you to make it run crisp?

This message has been edited. Last edited by: TRA-742,

216....on the 2010 they changed the acc pump cam, and it is actually rich!!! you actually need a 80 or 90 leak jet,and run the needle on the 3rd clip...f/s at 2 1/4. of course this is all with the acc pump wired and adjusted correctly.


these are 55 degree settings!!!

Jenson. What are the settings for like 10 freeeking degrees?!!!
We put studded tires on our test bike for 09-10 Honda linkage testing tomorrow. Freeeeeking cold.

quote:

Originally posted by TRA-742:
216 are you guys coming over in jan for the pasco arena-x? If I cant get it dialed in by then maybe i could hire you to make it run crisp?

I know you Tra. I wouldnt charge you a dime to help you out on that. Thanks for the info Jensensps. Any opinions on how well the 010 turns compared to 06-09? We may end up going for the 010 but I am not sure yet as I am concerned with how much they will change the bike when they are fuel injected in 011.

Taking into account I am amature test rider and not a setup guy- it seems to stick to the inside of a turn not drift out.. sticks better than my 08 honda and bit more stable. Suspension feels stiff new like and maybe more predictable. At first I was thinkin this not good is this all the motor? sounds like once carb tune setup is right it rips. The #120 made it shine. It was time for me to
get a new bike my honda was 08. If i had 09 i would of
waited for the efi 11 bike but then again your bikes proly get rode more often and alot harder. i bet the 11
will be trick. I have never road a 09 yz so i dont know
the difference but you guys can test ride mine at horn
and tell me. Dave said trevor is ridin his 09's again but did order a 10 yz250 2stroker-

This message has been edited. Last edited by: TRA-742,

The 09 chassis isnt much different than the 06-08's so what you are saying about the 010 is good news to us. Little Charlies only complaint ever on the Yamaha's has been that they dont turn as good as Honda's and Suzuki's. We have been contemplating switching to Suzuki's for 010 but if the Yami's turn as good as the other brands we will probably hold out and get the 010 Yami's.

Nothing turns better than a Zook. They turn toooooo good sometimes. Oversteer is what you would call it.

Yamaha's have a good balancing act of both. A very predictable bike.

A bike that doesn't turn is a 97 KX 250. Fast as hell in a straight line, but don't try to turn it. Haha.

MXA thinks very highly of themselves. If they recommend a jetting change or a different spring rate and the OEM listens then suddenly they are on the A list. Quite the ego.

I believe it is TWMX that posts actual lap times for different level riders. Track conditions can change so it isn't a perfect system but it's the best we've got.