02 YZ250 just doesn't feel like a yz250.

[johnrunner89]

So I've noticed in the past how my bro's yz250 doesn't hit like my yz250. His bike is pretty much all stock with the exception of an FMF exhaust. On all the yz250's ive rode the powerbands hit alot more violent so to say. I can hear the powerband go on but the bike just doesn't pull hard (but it still accelerates). When I take off from first, i can hear the powerband turn on like a light switch but the front end does not shoot up like I would expect m bike to. Mainly 1st-3rd do this, fourth and first feel like they pull just fine. The bike has tons of compression still. Any idea guys what you think this can be? Any info would be appreciated, I hope its not an expensive fix.

[KTMrideR146]

could be jetting?

[johnrunner89]

Very possible. We are both new to bikes so i'm not sure how to check/adjust the jetting but will look into it. Is it a hard thing to do?

[Fliip]

Read this over and over until you understand everything ?

https://www.thumpertalk.com/forum/showthread.php?t=412662

[johnrunner89]

Read this over and over until you understand everything ?

https://www.thumpertalk.com/forum/showthread.php?t=412662

Good read, thanks for the link. Alot of info to take in, I'm more confused than ever ?

[adam728]

Could be

Jetting

Time for a top end

Powervalve not functioning

[singletrkstar]

Also, what kind of FMF pipe? Pipe alters powerband delivery.

[nealy578]

Also, what kind of FMF pipe? Pipe alters powerband delivery.

Yup a Gnarly will not hit like a stock pipe

[CaptDan]

Your brother's bike is a 2002, what year is your bike?

Yamaha made some changes to the tune of YZs over the years, that's why I ask. ?

My friend's 2000 YZ has a much more noticable hit compared to our 2006.

[johnrunner89]

Also, what kind of FMF pipe? Pipe alters powerband delivery.

The exhaust is an FMF Q-stealth with a stock pipe. I have a turbine core II with a gnarly on my bike and I noticed how much smoother my bikes powerband hit compared to my bro's bike hit when the bike function normally.

Your brother's bike is a 2002, what year is your bike?

Yamaha made some changes to the tune of YZs over the years, that's why I ask. ?

My friend's 2000 YZ has a much more noticable hit compared to our 2006.

I have a 00' yz too. I'm sure our bikes do have a different hit, especially since his bike is mainly stock but what worries me is that the bike doesn't have the hard "hit" anymore. The sound of the powerband flicks right on but the bike doesn't pull hard especially in 1st and 2nd.

[arnego2]

When you compare the bikes how many hours has each top end of those bikes?

[johnrunner89]

When you compare the bikes how many hours has each top end of those bikes?

Honestly I don't know about his bike since he bought it preowned a few months ago. I haven't had a top end on my bike in like 3 years and my bike runs strong, starts first kick and has good compression but I plan to get it done soon.

[adam728]

Could be clutch slipping too. I've noticed in the past when the bike is revving, sounding healthy, but not pulling quite like it should, that soon the clutch goes bye-bye. Sometimes it's hard to tell the difference between clutch slip and traction. A quick pavement run lets you know real fast (if possible).

[johnrunner89]

Could be clutch slipping too. I've noticed in the past when the bike is revving, sounding healthy, but not pulling quite like it should, that soon the clutch goes bye-bye. Sometimes it's hard to tell the difference between clutch slip and traction. A quick pavement run lets you know real fast (if possible).

I first noticed the problem actually when riding the bike on my street and didn't think much of it since the ride on the street was very brief as I was just making sure the new asv clutch lever I put on it felt fine. Yesterday on the lakebed, I really noticed it again when taking off in first and second gear.

[johnrunner89]

Oh and one other thing I noticed was that a couple times in the day was after we started the bike, it was revving real high. Sounded like the choke was one, but after a couple seconds and a couple twist of the throttle it revved back at a normal idle. Probably another factor in the problem I would guess.?

[johnrunner89]

Problem fixed. Turned out to be the clutch cable was to tight so the clutch was not completely letting go. ? Just got done taking the bike out for a spin around the block and the front end would shoot up every time I got on the gas scaring me like i expected it to ?

[sdjclevland]

Could be clutch slipping too. I've noticed in the past when the bike is revving, sounding healthy, but not pulling quite like it should, that soon the clutch goes bye-bye. Sometimes it's hard to tell the difference between clutch slip and traction. A quick pavement run lets you know real fast (if possible).

Man I hope the clutch is what is wrong with mine also. What do you look for when taking it on the street? Just to make sure there is no wheel spin when testing?

[johnrunner89]

When taking it on the street, make sure its pulling hard and accerlating like it should. Also make sure the bike goes in and out of gear fine. Sometimes its hard to notice that on the dirt because when you get into the powerband it breaks the rear tire loose since you don't get traction as well as pavement.