21 yz 250

captmoto
Posts
5812
Joined
4/22/2009
Location
Rancho Cucamonga, CA US
4/19/2020 10:40am
Talisker wrote:
All new from the ground up!!!
All new from the grips up!
2
captmoto
Posts
5812
Joined
4/22/2009
Location
Rancho Cucamonga, CA US
4/19/2020 10:43am
yz133rider wrote:
The small bikes seem more secure because there isnt really any alternatives. Good that they finally brought them out of the 90s though!
I think they had to do that to keep up with the KTM mini's.
4/19/2020 11:01am
yz133rider wrote:
The small bikes seem more secure because there isnt really any alternatives. Good that they finally brought them out of the 90s though!
captmoto wrote:
I think they had to do that to keep up with the KTM mini's.
But they didn't even have a 65 (since the early 80s), so no need to "keep up" there.
mooch
Posts
1767
Joined
2/16/2008
Location
OH US
Fantasy
4/19/2020 11:04am
H4L wrote:
Yup. The transmission gears seem to be made of cheap aluminum material. Decent platform, but not the best Mx bike made as some have mentioned. Definitely...
Yup. The transmission gears seem to be made of cheap aluminum material. Decent platform, but not the best Mx bike made as some have mentioned. Definitely not the most durable bike made.
Thank goodness the aluminum gears on the '06 I've owned since new are still working flawlessly. 14 year old bike has been reliable as a rock and suspension was fantastic stock but was made even better by Enzo.
6

The Shop

mike_v812
Posts
29
Joined
11/19/2019
Location
Cleveland, OH US
4/19/2020 11:18am
I had 5 yz 250s over the past 10 years they are so solid!!! suspension is amazing, you never have to mess with jetting, i rode it indoors, outdoors, harscrambles it wasn’t the best every where but so versatile and reliable it can be revved or lugged. I just switched to a new four stroke because I just got sick of the same bike every year and I just wanted something that was modern. If I had more money to go around I’d have one of these things in the garage forever to scratch the itch.
3
Pirate421
Posts
1826
Joined
7/26/2015
Location
MA US
4/19/2020 11:48am
mike_v812 wrote:
I had 5 yz 250s over the past 10 years they are so solid!!! suspension is amazing, you never have to mess with jetting, i rode...
I had 5 yz 250s over the past 10 years they are so solid!!! suspension is amazing, you never have to mess with jetting, i rode it indoors, outdoors, harscrambles it wasn’t the best every where but so versatile and reliable it can be revved or lugged. I just switched to a new four stroke because I just got sick of the same bike every year and I just wanted something that was modern. If I had more money to go around I’d have one of these things in the garage forever to scratch the itch.
What 4 stroke did you go with and do you like it better than the YZ? I’m on the fence but my fence is just if I should go pick up another new YZ250, a 250sx or a 350sxf. I’ve had all of those three but my 250sx was the last generation 2014 and this latest gen is definitely better but I can’t make up my mind between yz 2 stroke and the sx two stroke.
TeamGreen
Posts
36680
Joined
11/25/2008
Location
Thru-out, CA US
4/19/2020 11:58am
After riding the New TX300i...

Yamaha needs to get serious about the YZ-2T models and do some R&D.
7
Pirate421
Posts
1826
Joined
7/26/2015
Location
MA US
4/19/2020 12:12pm
TeamGreen wrote:
After riding the New TX300i...

Yamaha needs to get serious about the YZ-2T models and do some R&D.
I think that may be the other option actually. I was between a 250sx and a 350sxf for Moto and harescrambles. A 300xc tpi May be the perfect mix between those two bikes it looks like.
H4L
Posts
2595
Joined
3/18/2016
Location
CA US
4/19/2020 1:19pm
mooch wrote:
Thank goodness the aluminum gears on the '06 I've owned since new are still working flawlessly. 14 year old bike has been reliable as a rock...
Thank goodness the aluminum gears on the '06 I've owned since new are still working flawlessly. 14 year old bike has been reliable as a rock and suspension was fantastic stock but was made even better by Enzo.
Consider yourself fortunate. Have owned 5 YZ2's from 02-11 model yrs. with a current 06 in the stable. It is already showing signs of having a notchy trans while shifting gears & also missing gears. The bike has maybe 10-12 actual hrs. from the showroom floor.


1
40
Posts
260
Joined
12/26/2015
Location
WY US
4/19/2020 3:03pm Edited Date/Time 4/19/2020 3:05pm
The transmissions are an achilles heel.They have a 3 dog engagement system with a weakly supported 4th gear. Additionally, the shifting forks are staked rigidly to their respective pins. The net effect of this design is that the forks and pins slide simultaneously together as a single unit inside the crankcase pockets when the shifting cam rotates during shifting.. Other manufacturers use a shifting fork over pin design where the fork slides over the pin when the cam is rotated. Only the cam and fork move..
The Yamaha design is also more difficult to re-assemble due to the staked shifting fork design.
However, the YZ transmission does actually shift very well when new, and the close gear ratios are well suited for mx.
The transmission needs a redesign. Not for the purpose of improving the actual shifting, but for overall durability and modernized mechanical functionality.
9
Lightning78
Posts
6353
Joined
12/12/2007
Location
Huntington Beach, CA US
4/19/2020 3:18pm
Back in 2012 I was okay with the YZ being identical to an 06. Seemed smart since they still sold a ton. But damn, that model...
Back in 2012 I was okay with the YZ being identical to an 06. Seemed smart since they still sold a ton. But damn, that model is 15 years old! Imagine 20 years ago buying a brand “new” 2000 YZ, but it’s a 1986 model with BNG.

I had a YZ250 not too long ago and it really does feel dated when you ride it. The ergos, feel, etc. 15 years is too damn long, I want a new YZ to drool over.
Its still probably the best suspended 250 2 stroke out there.

When it is not broken, do you really need to change it?
After 20 years, yes. I just want some updated ergos and misc parts!!
Putting it into the 2010-2013 YZ250f frame would be bitchin


2
Lightning78
Posts
6353
Joined
12/12/2007
Location
Huntington Beach, CA US
4/19/2020 3:20pm

2
8
sandman768
Posts
7970
Joined
3/21/2014
Location
Saratoga Springs, NY US
4/19/2020 3:35pm
40 wrote:
The transmissions are an achilles heel.They have a 3 dog engagement system with a weakly supported 4th gear. Additionally, the shifting forks are staked rigidly to...
The transmissions are an achilles heel.They have a 3 dog engagement system with a weakly supported 4th gear. Additionally, the shifting forks are staked rigidly to their respective pins. The net effect of this design is that the forks and pins slide simultaneously together as a single unit inside the crankcase pockets when the shifting cam rotates during shifting.. Other manufacturers use a shifting fork over pin design where the fork slides over the pin when the cam is rotated. Only the cam and fork move..
The Yamaha design is also more difficult to re-assemble due to the staked shifting fork design.
However, the YZ transmission does actually shift very well when new, and the close gear ratios are well suited for mx.
The transmission needs a redesign. Not for the purpose of improving the actual shifting, but for overall durability and modernized mechanical functionality.
Sounds like you have rebuilt a few of these 😂
2
40
Posts
260
Joined
12/26/2015
Location
WY US
4/19/2020 3:53pm Edited Date/Time 4/20/2020 7:19am


Look carefully at #20, #15, #6. These gears engage with their opposing gear using only 3 engagement dogs. Other manufacturers use 4. Some KTM's with Pankl gearbox use 5. This is a weak design.
Look at #8. It's a bushing ("collar" in Yamaspeak) which weakly supports #7 (4th gear). Why did Yamaha use a "collar" to support 4th gear? Because they probably had a surplus inventory of #7's leftover from another bike. Rather than spec a new gear, they used an inexpensive bushing to get the inside diameter of #7 gear to match the shaft. The net effect is that #7 gear is not strongly supported on the shaft, hence many 4th gear problems.. Weak design.
How about the actual gear metallurgy? Yet another weak, cost saving specification.
4
H4L
Posts
2595
Joined
3/18/2016
Location
CA US
4/19/2020 4:57pm
40 wrote:
[img]https://p.vitalmx.com/photos/forums/2020/04/19/421435/s1200_YZ250_Transmission.jpg[/img] Look carefully at #20, #15, #6. These gears engage with their opposing gear using only 3 engagement dogs. Other manufacturers use 4. Some KTM's with...


Look carefully at #20, #15, #6. These gears engage with their opposing gear using only 3 engagement dogs. Other manufacturers use 4. Some KTM's with Pankl gearbox use 5. This is a weak design.
Look at #8. It's a bushing ("collar" in Yamaspeak) which weakly supports #7 (4th gear). Why did Yamaha use a "collar" to support 4th gear? Because they probably had a surplus inventory of #7's leftover from another bike. Rather than spec a new gear, they used an inexpensive bushing to get the inside diameter of #7 gear to match the shaft. The net effect is that #7 gear is not strongly supported on the shaft, hence many 4th gear problems.. Weak design.
How about the actual gear metallurgy? Yet another weak, cost saving specification.
Thnxz for posting. I felt the trans on the YZ was / is a weak point. Seems like no one talks about it though..
4/19/2020 5:02pm
H4L wrote:
Yup. The transmission gears seem to be made of cheap aluminum material. Decent platform, but not the best Mx bike made as some have mentioned. Definitely...
Yup. The transmission gears seem to be made of cheap aluminum material. Decent platform, but not the best Mx bike made as some have mentioned. Definitely not the most durable bike made.
mooch wrote:
Thank goodness the aluminum gears on the '06 I've owned since new are still working flawlessly. 14 year old bike has been reliable as a rock...
Thank goodness the aluminum gears on the '06 I've owned since new are still working flawlessly. 14 year old bike has been reliable as a rock and suspension was fantastic stock but was made even better by Enzo.
I have to say, I’ve had an ‘07 and an ‘06 since 2009. I’ve had a handful of other bikes and brands, but never go without a YZ250 in the stable. I’ve never had a tranny problem. I really don’t get it.
4/19/2020 5:05pm Edited Date/Time 4/19/2020 5:06pm
H4L wrote:
Yup. The transmission gears seem to be made of cheap aluminum material. Decent platform, but not the best Mx bike made as some have mentioned. Definitely...
Yup. The transmission gears seem to be made of cheap aluminum material. Decent platform, but not the best Mx bike made as some have mentioned. Definitely not the most durable bike made.
mooch wrote:
Thank goodness the aluminum gears on the '06 I've owned since new are still working flawlessly. 14 year old bike has been reliable as a rock...
Thank goodness the aluminum gears on the '06 I've owned since new are still working flawlessly. 14 year old bike has been reliable as a rock and suspension was fantastic stock but was made even better by Enzo.
I have to say, I’ve had an ‘07 and an ‘06 since 2009. I’ve had a handful of other bikes and brands, but never go without...
I have to say, I’ve had an ‘07 and an ‘06 since 2009. I’ve had a handful of other bikes and brands, but never go without a YZ250 in the stable. I’ve never had a tranny problem. I really don’t get it.
Depends on riding style/level. Some are harder on bikes. A bike by a novice on a trail vs a fast B rider on a track has different demands on the bike.
1
Moto520
Posts
3623
Joined
2/4/2013
Location
Schaumburg, IL US
4/19/2020 7:13pm
The dog gear thingy is what went out on my 2005. It would slip out of gear. Most of us onow that this is an issue but it can easily make 80 hours before anything happens. When it does happen.....it might not grenade the whole transmission
Zesiger 112
Posts
2325
Joined
3/4/2013
Location
Galveston, TX US
4/19/2020 7:31pm Edited Date/Time 4/19/2020 7:31pm
Back in 2012 I was okay with the YZ being identical to an 06. Seemed smart since they still sold a ton. But damn, that model...
Back in 2012 I was okay with the YZ being identical to an 06. Seemed smart since they still sold a ton. But damn, that model is 15 years old! Imagine 20 years ago buying a brand “new” 2000 YZ, but it’s a 1986 model with BNG.

I had a YZ250 not too long ago and it really does feel dated when you ride it. The ergos, feel, etc. 15 years is too damn long, I want a new YZ to drool over.
Its still probably the best suspended 250 2 stroke out there.

When it is not broken, do you really need to change it?
After 20 years, yes. I just want some updated ergos and misc parts!!
There are dozens of aftermarket companies who will help with that. And so many forums to explain anything you can imagine to do to these bikes. The homework has been done already.
cz2crf2wc
Posts
537
Joined
11/22/2013
Location
Solona Beach, CA US
4/19/2020 7:38pm
That YZ 250 platform could go down in history as the best all around motocross bike ever. Name one other bike that has been right there...
That YZ 250 platform could go down in history as the best all around motocross bike ever. Name one other bike that has been right there for so long.
PW 50
1
4/19/2020 8:34pm Edited Date/Time 4/19/2020 8:35pm
I'll bet the marketing folk are wishing they had a revised bike to announce right now. New YZ125/250 would be epic but just about any new model would fly right now with the captive lockdown audience (where is that 2021 CRF450?)
mxdevon
Posts
243
Joined
10/25/2016
Location
Coeur D'Alene, ID US
4/20/2020 3:27am
Of the literal boatload of bikes ive owned....the only one I’ve had transmission issues with was my 09 YZ250. Rode great until it started popping out of gear. Haven’t owned one since.
gregyou
Posts
733
Joined
1/26/2020
Location
AU
4/20/2020 3:56am
If they just updated the ergo’s on it they would sell boat loads more. The seat and tank junction is to old school
1
1
DynoDan22
Posts
769
Joined
9/7/2011
Location
Victorville, CA US
4/20/2020 6:37am
I've rebuilt many a YZ250 transmission. 3rd, 4th and the center shift were always toast. I rebuilt two this year alone.
2
resetjet
Posts
2537
Joined
3/16/2012
Location
Tampa, FL US
4/20/2020 6:59am
Well since they are exported out of japan, i dont see them doing it. They have a Different set of rules then eu. Epa will kill the 2 stroke soon, why put money into it. So far ktm has enough customers in the eu to put money into it. E4 may change that.
40
Posts
260
Joined
12/26/2015
Location
WY US
4/20/2020 7:38am Edited Date/Time 4/20/2020 8:03am
gregyou wrote:
If they just updated the ergo’s on it they would sell boat loads more. The seat and tank junction is to old school
They need to do more than just this.
The steering is not quick enough. It does not need to be Suzuki quick at the expense of headshake, but the YZ's bias toward high speed stability needs to be better balanced with quicker, more precise steering.
The brakes need an update. There is a reason why YZ guys install Honda brake pads. However this still pales in comparison to a Brembo unit. All of the Japanese mfgrs are guilty here.
The clutch needs an update. Notching aluminum baskets, and quick wearing and fade prone overall. Again, all Japanese are guilty.
The YZ ergonomics- John Deer tractor anyone? Needs a lot of work.
Keep the Kayaba SSS. Lots of work required elsewhere.
2
Lightning78
Posts
6353
Joined
12/12/2007
Location
Huntington Beach, CA US
4/20/2020 7:57am
gregyou wrote:
If they just updated the ergo’s on it they would sell boat loads more. The seat and tank junction is to old school
40 wrote:
They need to do more than just this. The steering is not quick enough. It does not need to be Suzuki quick at the expense of...
They need to do more than just this.
The steering is not quick enough. It does not need to be Suzuki quick at the expense of headshake, but the YZ's bias toward high speed stability needs to be better balanced with quicker, more precise steering.
The brakes need an update. There is a reason why YZ guys install Honda brake pads. However this still pales in comparison to a Brembo unit. All of the Japanese mfgrs are guilty here.
The clutch needs an update. Notching aluminum baskets, and quick wearing and fade prone overall. Again, all Japanese are guilty.
The YZ ergonomics- John Deer tractor anyone? Needs a lot of work.
Keep the Kayaba SSS. Lots of work required elsewhere.
I agree about the handling....I've always felt with my 03 it took a lot of effort as compared to any other bike to settle in and initiate a turn, then again, I could come into turn so hot and carry a lot more speed in and around a corner bec my front wheel NEVER slid knifed or pushed.
All the YZ/YZF's I've ever ridden felt like they had a near flat front tire in a sense of how glued to the ground it felt.
40
Posts
260
Joined
12/26/2015
Location
WY US
4/20/2020 7:57am Edited Date/Time 4/20/2020 3:52pm


Here's another gem of Yamaha engineering.
Note that shifting forks #11, #12 and #13 are a single piece unit rigidly staked to their pins. The forks and pins move simultaneously together as a single unit when the shifting cam rotates. Other manufacturers use a fork over pin design as separate parts.
What does this mean operationally?
It means that on the Yamaha as the pins move together with the fork, the side of the pin that moves out of its crankcase support pocket will have less support than the opposite side of the pin which moves further into it's respective pocket. The out moving side will absolutely have less support, while the in moving side gets more. It also makes transmission reassembly more of a pain in the ass.
As opposed to other manufacturers using the fork sliding over the pin design which leaves the pins equally supported and equally spaced in both case halves at all times since only the fork moves. The pins remain fully supported and stationary.
Which design makes more logical sense?. The Yamaha way, or the other way?
3
yz133rider
Posts
5033
Joined
8/1/2013
Location
Avondale, PA US
4/20/2020 8:00am
gregyou wrote:
If they just updated the ergo’s on it they would sell boat loads more. The seat and tank junction is to old school
40 wrote:
They need to do more than just this. The steering is not quick enough. It does not need to be Suzuki quick at the expense of...
They need to do more than just this.
The steering is not quick enough. It does not need to be Suzuki quick at the expense of headshake, but the YZ's bias toward high speed stability needs to be better balanced with quicker, more precise steering.
The brakes need an update. There is a reason why YZ guys install Honda brake pads. However this still pales in comparison to a Brembo unit. All of the Japanese mfgrs are guilty here.
The clutch needs an update. Notching aluminum baskets, and quick wearing and fade prone overall. Again, all Japanese are guilty.
The YZ ergonomics- John Deer tractor anyone? Needs a lot of work.
Keep the Kayaba SSS. Lots of work required elsewhere.
I agree about the handling....I've always felt with my 03 it took a lot of effort as compared to any other bike to settle in and...
I agree about the handling....I've always felt with my 03 it took a lot of effort as compared to any other bike to settle in and initiate a turn, then again, I could come into turn so hot and carry a lot more speed in and around a corner bec my front wheel NEVER slid knifed or pushed.
All the YZ/YZF's I've ever ridden felt like they had a near flat front tire in a sense of how glued to the ground it felt.
Try 22 mm clamps from ride engineering or luxon and youll be blown away at the cornering improvement.
1
GripNRip617
Posts
198
Joined
3/13/2018
Location
Austin, TX US
4/20/2020 9:27am
Bought a used 2015 YZ250 in 2015, and still own the bike. I echo the transmission pains others have stated, on my 3rd transmission rebuild with 230 hours on the bike.
1

Post a reply to: 21 yz 250

The Latest