YZ250 Tom Morgan Engine…2 stroke heaven

Edited Date/Time 3/14/2023 6:00pm

Hello Guys, I just want to share with you my experience with my new bike, a Yamaha YZ250 2 stroke.

After 10 years riding 4 strokes, I was missing something, I ride just for fun, I m a 44 years old, 210 lbs, 6,3, only moto guy.

I got a YZ250 mid december 2022, since that day my 2022 CRF450R (XPR Vortex ECU, full yosh system) is collecting dust.

Bike feels light and agile, engine wise is no contest to a 450 4 strokes, it feels slow, I need to work hard with the gearbox and clutch in order to be in the powerband. For some jumps it was harder to clear the gaps, specially coming from tight corners…..I really need to focus on technique and work with the gearbox/clutch.
 

Stock engine is really friendly, building power from low revs, once on the pipe is really fun, over rev was poor (if you compare to a 4 stroke) powerband feels short.

Bike ergos feels very similar to my Honda, it took me 10 min to feel at home.

Following advices from Tom Morgan, I did some mods to the engine.

TMR head modification to pump gas

FMF fatty pipe

PC 304 silencer

V Force 3 reeds

Engine was running strong, easy to ride, nice improvement from stock.

Last piece of the cake was the addition of a TMR ported Cylinder……what a difference!!!.

Tom did an awesome job (cylinder ports looks way different that oem), engine pulls much stronger from midrange and topend power and over rev is simple awesome.

Partial throttle opening are also well improved, engine pulls with authority from low revs, now I can use 4 gear with confidence and use more 3rd gear in corners (2nd gear before porting).

Bottom line I m very happy with my YZ250, bike is a blast to ride, it hard to explain but I feel that I found something that I was missing, dont know if its the smell, the sound, the jetting, the premix, or what…..all I can say I m enjoying my TMR YZ250 alot!!.

Big thanks to Tom, excelent products/advices, and top notch customer service.

One happy 2 stroke owner.

Regards!!

 

42
2
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jeffro503
Posts
27635
Joined
7/22/2007
Location
St Helens, OR, USA
3/14/2023 5:09pm

I'm a big supporter of Tom Morgan as well. Before I made the switch to 4 strokes in 2002 , Tom built my motors in 95' , 97' and 99'. I can honestly say that when I lined up on the gates back then , I had the fastest motor there. I remember my 97' being crazy strong. In 99' I asked him to just clean things up and not get so crazy , and my 99' motor was incredible. I talked to Tom multiple times on the phone about jetting and so forth , and his customer service was top notch!  I loved using his stuff , and if I really need a fast motor again....he would be the first one I called. One awesome dude , and awesome company.

7
1
Magoofan
Posts
10401
Joined
5/4/2021
Location
Shadow Glen (for those who remember), CA, USA
3/14/2023 5:15pm

Long live the Brraaaap....

Post up some pics.

 

4
chad_111
Posts
303
Joined
4/22/2016
Location
CA
3/14/2023 5:15pm
Hello Guys, I just want to share with you my experience with my new bike, a Yamaha YZ250 2 stroke. After 10 years riding 4 strokes...

Hello Guys, I just want to share with you my experience with my new bike, a Yamaha YZ250 2 stroke.

After 10 years riding 4 strokes, I was missing something, I ride just for fun, I m a 44 years old, 210 lbs, 6,3, only moto guy.

I got a YZ250 mid december 2022, since that day my 2022 CRF450R (XPR Vortex ECU, full yosh system) is collecting dust.

Bike feels light and agile, engine wise is no contest to a 450 4 strokes, it feels slow, I need to work hard with the gearbox and clutch in order to be in the powerband. For some jumps it was harder to clear the gaps, specially coming from tight corners…..I really need to focus on technique and work with the gearbox/clutch.
 

Stock engine is really friendly, building power from low revs, once on the pipe is really fun, over rev was poor (if you compare to a 4 stroke) powerband feels short.

Bike ergos feels very similar to my Honda, it took me 10 min to feel at home.

Following advices from Tom Morgan, I did some mods to the engine.

TMR head modification to pump gas

FMF fatty pipe

PC 304 silencer

V Force 3 reeds

Engine was running strong, easy to ride, nice improvement from stock.

Last piece of the cake was the addition of a TMR ported Cylinder……what a difference!!!.

Tom did an awesome job (cylinder ports looks way different that oem), engine pulls much stronger from midrange and topend power and over rev is simple awesome.

Partial throttle opening are also well improved, engine pulls with authority from low revs, now I can use 4 gear with confidence and use more 3rd gear in corners (2nd gear before porting).

Bottom line I m very happy with my YZ250, bike is a blast to ride, it hard to explain but I feel that I found something that I was missing, dont know if its the smell, the sound, the jetting, the premix, or what…..all I can say I m enjoying my TMR YZ250 alot!!.

Big thanks to Tom, excelent products/advices, and top notch customer service.

One happy 2 stroke owner.

Regards!!

 

Just to clarify, you're still able to run pump gas with no knocking with these mods?

1
jeffro503
Posts
27635
Joined
7/22/2007
Location
St Helens, OR, USA
3/14/2023 5:25pm
Hello Guys, I just want to share with you my experience with my new bike, a Yamaha YZ250 2 stroke. After 10 years riding 4 strokes...

Hello Guys, I just want to share with you my experience with my new bike, a Yamaha YZ250 2 stroke.

After 10 years riding 4 strokes, I was missing something, I ride just for fun, I m a 44 years old, 210 lbs, 6,3, only moto guy.

I got a YZ250 mid december 2022, since that day my 2022 CRF450R (XPR Vortex ECU, full yosh system) is collecting dust.

Bike feels light and agile, engine wise is no contest to a 450 4 strokes, it feels slow, I need to work hard with the gearbox and clutch in order to be in the powerband. For some jumps it was harder to clear the gaps, specially coming from tight corners…..I really need to focus on technique and work with the gearbox/clutch.
 

Stock engine is really friendly, building power from low revs, once on the pipe is really fun, over rev was poor (if you compare to a 4 stroke) powerband feels short.

Bike ergos feels very similar to my Honda, it took me 10 min to feel at home.

Following advices from Tom Morgan, I did some mods to the engine.

TMR head modification to pump gas

FMF fatty pipe

PC 304 silencer

V Force 3 reeds

Engine was running strong, easy to ride, nice improvement from stock.

Last piece of the cake was the addition of a TMR ported Cylinder……what a difference!!!.

Tom did an awesome job (cylinder ports looks way different that oem), engine pulls much stronger from midrange and topend power and over rev is simple awesome.

Partial throttle opening are also well improved, engine pulls with authority from low revs, now I can use 4 gear with confidence and use more 3rd gear in corners (2nd gear before porting).

Bottom line I m very happy with my YZ250, bike is a blast to ride, it hard to explain but I feel that I found something that I was missing, dont know if its the smell, the sound, the jetting, the premix, or what…..all I can say I m enjoying my TMR YZ250 alot!!.

Big thanks to Tom, excelent products/advices, and top notch customer service.

One happy 2 stroke owner.

Regards!!

 

chad_111 wrote:

Just to clarify, you're still able to run pump gas with no knocking with these mods?

Mine ( back then ) Required at least a 1/2 and 1/2 race fuel blend. Strait pump gas ran like shit. Take that back.....not like shit , but the race gas really woke the motor up. Plus , they ran cooler.

1

The Shop

sandman768
Posts
8132
Joined
3/21/2014
Location
Saratoga Springs, NY, USA
3/14/2023 5:32pm

Tom did my 96 CR250…. Full blown everything you got package, this bike is incredibly fast & never stops pulling… 2806236D-54E8-49F7-8E97-272361C3CC29.jpeg?VersionId=TH

 

24
3/14/2023 5:37pm
Hello Guys, I just want to share with you my experience with my new bike, a Yamaha YZ250 2 stroke. After 10 years riding 4 strokes...

Hello Guys, I just want to share with you my experience with my new bike, a Yamaha YZ250 2 stroke.

After 10 years riding 4 strokes, I was missing something, I ride just for fun, I m a 44 years old, 210 lbs, 6,3, only moto guy.

I got a YZ250 mid december 2022, since that day my 2022 CRF450R (XPR Vortex ECU, full yosh system) is collecting dust.

Bike feels light and agile, engine wise is no contest to a 450 4 strokes, it feels slow, I need to work hard with the gearbox and clutch in order to be in the powerband. For some jumps it was harder to clear the gaps, specially coming from tight corners…..I really need to focus on technique and work with the gearbox/clutch.
 

Stock engine is really friendly, building power from low revs, once on the pipe is really fun, over rev was poor (if you compare to a 4 stroke) powerband feels short.

Bike ergos feels very similar to my Honda, it took me 10 min to feel at home.

Following advices from Tom Morgan, I did some mods to the engine.

TMR head modification to pump gas

FMF fatty pipe

PC 304 silencer

V Force 3 reeds

Engine was running strong, easy to ride, nice improvement from stock.

Last piece of the cake was the addition of a TMR ported Cylinder……what a difference!!!.

Tom did an awesome job (cylinder ports looks way different that oem), engine pulls much stronger from midrange and topend power and over rev is simple awesome.

Partial throttle opening are also well improved, engine pulls with authority from low revs, now I can use 4 gear with confidence and use more 3rd gear in corners (2nd gear before porting).

Bottom line I m very happy with my YZ250, bike is a blast to ride, it hard to explain but I feel that I found something that I was missing, dont know if its the smell, the sound, the jetting, the premix, or what…..all I can say I m enjoying my TMR YZ250 alot!!.

Big thanks to Tom, excelent products/advices, and top notch customer service.

One happy 2 stroke owner.

Regards!!

 

chad_111 wrote:

Just to clarify, you're still able to run pump gas with no knocking with these mods?

I m running 25% VP C12 and 75% pump fuel 91 octanes (R+M/2)

Race gas is crazy expensive here….my setting is for pump gas, but to be safe I add some race fuel.

Tom has 3 options, pump fuel, 50/50 and race fuel setting.

 

2
3/14/2023 5:40pm
sandman768 wrote:
Tom did my 96 CR250…. Full blown everything you got package, this bike is incredibly fast & never stops pulling…   

Tom did my 96 CR250…. Full blown everything you got package, this bike is incredibly fast & never stops pulling… 2806236D-54E8-49F7-8E97-272361C3CC29.jpeg?VersionId=TH

 

What a beauty!!

3
RMT
Posts
1269
Joined
8/16/2006
Location
Chicagoland, IL, USA
3/14/2023 10:58pm

“it hard to explain but I feel that I found something that I was missing”

Maybe a kickstarter?  Lol.  Cool bike.  

1
Richy
Posts
3093
Joined
7/18/2020
Location
UK, GB
3/14/2023 11:56pm Edited Date/Time 3/14/2023 11:57pm

The thumbs down is probably Varner...

Good to hear it got the spark back, bike looks sweet and TMR are definitely doing it right. You only hear good things about Tom and that is incredibly rare with that kind of work 👍

10
2
PNWMXer
Posts
1761
Joined
1/13/2022
Location
Washington, WA, USA
3/15/2023 4:49am

Another vote for Tom. He did an excellent job on my 02 CR250. I was equally impressed with his willingness to talk about tuning and engine advice in general. The tuning guide he sent with the cylinder was incredibly beneficial as well. Great guy who does great work.

7
beamer
Posts
866
Joined
8/16/2006
Location
Squaw River, CA
3/15/2023 5:46am

Tom has done 4 motor packages for us, all 2 stroke.  The difference made on the RM250 was unreal, we plan on getting a YZ250 next, cant wait.  His work and focus on the customer is absolute top notch.

2
Cobbler
Posts
432
Joined
3/13/2023
Location
cairo, IL, USA
3/15/2023 5:49am
sandman768 wrote:
Tom did my 96 CR250…. Full blown everything you got package, this bike is incredibly fast & never stops pulling…   

Tom did my 96 CR250…. Full blown everything you got package, this bike is incredibly fast & never stops pulling… 2806236D-54E8-49F7-8E97-272361C3CC29.jpeg?VersionId=TH

 

My favorite track in the world right there. You lucky dawg.

1
Cobbler
Posts
432
Joined
3/13/2023
Location
cairo, IL, USA
3/15/2023 5:57am

Just curious, what about does it cost to have a Cylinder worked on a little bit? If a man wanted to have a little "messaging" done without anything extreme.

1
3/15/2023 6:00am
PNWMXer wrote:
Another vote for Tom. He did an excellent job on my 02 CR250. I was equally impressed with his willingness to talk about tuning and engine...

Another vote for Tom. He did an excellent job on my 02 CR250. I was equally impressed with his willingness to talk about tuning and engine advice in general. The tuning guide he sent with the cylinder was incredibly beneficial as well. Great guy who does great work.

How was the power on the case reed after his work? I have a cylinder getting sent back to me from another builder today and plan on using TM for my next cylinder 

1
3/15/2023 6:00am
RMT wrote:

“it hard to explain but I feel that I found something that I was missing”

Maybe a kickstarter?  Lol.  Cool bike.  

One kick to fire up it definitely part of the 2 stroke magic.

Braaapp!!

2
bvm111
Posts
10122
Joined
7/1/2008
Location
Las Vegas, NV, USA
3/15/2023 6:02am

Tom did my 06 KX250 motor and it’s awesome, it does call for straight C12 though. I have run Sunoco 110 and it runs great with that as well and is a bit more economical than C12. I can say that he was awesome to work with, available via phone multiple times throughout the process and after to help with jetting. I wouldn’t use anyone else and can happily recommend him to anyone looking for motor work! 

3
1
Coach529
Posts
406
Joined
4/1/2008
Location
Coeur d'Alene, ID, USA
3/15/2023 8:12am

Tom built me a 295cc cylinder for my YZ a couple years ago. The things is magic. Absolutely love it!!

 

TMR 295

 

6
Karlsrad
Posts
64
Joined
8/13/2018
Location
Carlsbad, CA, USA
3/15/2023 10:24am

I have a YZ250 Cylinder and Head in with TMR right now, can't wait to get it back and give it a rip! 

1
fourfourone
Posts
3046
Joined
10/14/2017
Location
86oh, CT, USA
3/15/2023 10:34am

This thread makes me want another 2 stroke. 

2
Wycked31
Posts
491
Joined
3/25/2014
Location
West Palm Beach, FL, USA
3/15/2023 11:07am

Tom has done a garage full of motors for me. My 91 KX500, 03 YZ295 and 97 KX250. Bikes rip.

 

image-20230315140057-1

image-20230315140137-2

image-20230315140650-3

10
quadmx301
Posts
506
Joined
9/23/2014
Location
Murrieta, CA, USA
3/15/2023 3:26pm

Just put on my TMR YZ250 head, and he is in the finally stages of my KX500 full motor. He’s the man!

3/15/2023 7:02pm
Coach529 wrote:
Tom built me a 295cc cylinder for my YZ a couple years ago. The things is magic. Absolutely love it!!    

Tom built me a 295cc cylinder for my YZ a couple years ago. The things is magic. Absolutely love it!!

 

TMR 295

 

How did it pull up top compared to when it was a 250?

Goldmember
Posts
671
Joined
12/23/2021
Location
Tel Aviv, IL
3/15/2023 10:45pm
Hello Guys, I just want to share with you my experience with my new bike, a Yamaha YZ250 2 stroke. After 10 years riding 4 strokes...

Hello Guys, I just want to share with you my experience with my new bike, a Yamaha YZ250 2 stroke.

After 10 years riding 4 strokes, I was missing something, I ride just for fun, I m a 44 years old, 210 lbs, 6,3, only moto guy.

I got a YZ250 mid december 2022, since that day my 2022 CRF450R (XPR Vortex ECU, full yosh system) is collecting dust.

Bike feels light and agile, engine wise is no contest to a 450 4 strokes, it feels slow, I need to work hard with the gearbox and clutch in order to be in the powerband. For some jumps it was harder to clear the gaps, specially coming from tight corners…..I really need to focus on technique and work with the gearbox/clutch.
 

Stock engine is really friendly, building power from low revs, once on the pipe is really fun, over rev was poor (if you compare to a 4 stroke) powerband feels short.

Bike ergos feels very similar to my Honda, it took me 10 min to feel at home.

Following advices from Tom Morgan, I did some mods to the engine.

TMR head modification to pump gas

FMF fatty pipe

PC 304 silencer

V Force 3 reeds

Engine was running strong, easy to ride, nice improvement from stock.

Last piece of the cake was the addition of a TMR ported Cylinder……what a difference!!!.

Tom did an awesome job (cylinder ports looks way different that oem), engine pulls much stronger from midrange and topend power and over rev is simple awesome.

Partial throttle opening are also well improved, engine pulls with authority from low revs, now I can use 4 gear with confidence and use more 3rd gear in corners (2nd gear before porting).

Bottom line I m very happy with my YZ250, bike is a blast to ride, it hard to explain but I feel that I found something that I was missing, dont know if its the smell, the sound, the jetting, the premix, or what…..all I can say I m enjoying my TMR YZ250 alot!!.

Big thanks to Tom, excelent products/advices, and top notch customer service.

One happy 2 stroke owner.

Regards!!

 

Do you have dyno data of before and after to support these claims?

3/15/2023 10:53pm Edited Date/Time 3/15/2023 10:57pm
Hello Guys, I just want to share with you my experience with my new bike, a Yamaha YZ250 2 stroke. After 10 years riding 4 strokes...

Hello Guys, I just want to share with you my experience with my new bike, a Yamaha YZ250 2 stroke.

After 10 years riding 4 strokes, I was missing something, I ride just for fun, I m a 44 years old, 210 lbs, 6,3, only moto guy.

I got a YZ250 mid december 2022, since that day my 2022 CRF450R (XPR Vortex ECU, full yosh system) is collecting dust.

Bike feels light and agile, engine wise is no contest to a 450 4 strokes, it feels slow, I need to work hard with the gearbox and clutch in order to be in the powerband. For some jumps it was harder to clear the gaps, specially coming from tight corners…..I really need to focus on technique and work with the gearbox/clutch.
 

Stock engine is really friendly, building power from low revs, once on the pipe is really fun, over rev was poor (if you compare to a 4 stroke) powerband feels short.

Bike ergos feels very similar to my Honda, it took me 10 min to feel at home.

Following advices from Tom Morgan, I did some mods to the engine.

TMR head modification to pump gas

FMF fatty pipe

PC 304 silencer

V Force 3 reeds

Engine was running strong, easy to ride, nice improvement from stock.

Last piece of the cake was the addition of a TMR ported Cylinder……what a difference!!!.

Tom did an awesome job (cylinder ports looks way different that oem), engine pulls much stronger from midrange and topend power and over rev is simple awesome.

Partial throttle opening are also well improved, engine pulls with authority from low revs, now I can use 4 gear with confidence and use more 3rd gear in corners (2nd gear before porting).

Bottom line I m very happy with my YZ250, bike is a blast to ride, it hard to explain but I feel that I found something that I was missing, dont know if its the smell, the sound, the jetting, the premix, or what…..all I can say I m enjoying my TMR YZ250 alot!!.

Big thanks to Tom, excelent products/advices, and top notch customer service.

One happy 2 stroke owner.

Regards!!

 

Goldmember wrote:

Do you have dyno data of before and after to support these claims?

Not a lot of weekend warriors are going to have dyno data from before and after engine mods. And I dont see anywhere that he was claiming any HP numbers. 
 

I would think your comment would be more inline if he was claiming a percentage of more power over stock, or a ridiculous increase in power. 

2
jeffro503
Posts
27635
Joined
7/22/2007
Location
St Helens, OR, USA
3/15/2023 11:05pm

Weird , but tonight I was out in the shop going through some old stuff , reorganizing. Came across some of my old Tom Morgan stuff. Kinda neat running across this old stuff. IMG 20230315 214310963.jpg?VersionId=ZfJ43NcUydCgLMlFJ

 

6
3/15/2023 11:10pm
jeffro503 wrote:
Weird , but tonight I was out in the shop going through some old stuff , reorganizing. Came across some of my old Tom Morgan stuff...

Weird , but tonight I was out in the shop going through some old stuff , reorganizing. Came across some of my old Tom Morgan stuff. Kinda neat running across this old stuff. IMG 20230315 214310963.jpg?VersionId=ZfJ43NcUydCgLMlFJ

 

Very cool. I received my cylinder from a well know company today and didn’t get so much as an engine sticker or spec sheet. Not even a piece of paper in the box actually lol

Coach529
Posts
406
Joined
4/1/2008
Location
Coeur d'Alene, ID, USA
3/16/2023 6:17am
Coach529 wrote:
Tom built me a 295cc cylinder for my YZ a couple years ago. The things is magic. Absolutely love it!!    

Tom built me a 295cc cylinder for my YZ a couple years ago. The things is magic. Absolutely love it!!

 

TMR 295

 

How did it pull up top compared to when it was a 250?

It pulls as good or better I feel. I run a stock pipe with a long silencer. The bike was build for single track, but it gets ridden on moto quite a bit. A PC pipe would help the mid top IMO.

1
Moto Mofo
Posts
889
Joined
1/17/2008
Location
USA
3/16/2023 7:00am Edited Date/Time 3/16/2023 7:03am
Coach529 wrote:
It pulls as good or better I feel. I run a stock pipe with a long silencer. The bike was build for single track, but it...

It pulls as good or better I feel. I run a stock pipe with a long silencer. The bike was build for single track, but it gets ridden on moto quite a bit. A PC pipe would help the mid top IMO.

Does it seem to run much hotter than it did as a 250? I’ve considered doing the same with my YZ offroad bike. I’ve never boiled over a YZ, but have had a few KTM two strokes that would occasionally. 

Moto Mofo
Posts
889
Joined
1/17/2008
Location
USA
3/16/2023 7:01am

Tom Morgan is the only motor guy I can think of that NEVER has any negative, or even neutral, feedback. Everything I’ve ever seen/heard/read about him has been extremely positive. 

4

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