Thinking about switching from a KX to a YZF.

tschweitzer622
Edited Date/Time 6/21/2023 3:09pm

Tossing around the idea of switching to a YZF 450. A few different random reasons…. Just bought a 2023 SR450 in December and I do not Like the engine or ECU, at all. Starts are fucking horrible off the gate. I’m not fast enough to justify re-mapping it. I was hoping the amount I spent on it, it would be ready to race. I switched the rear to a 51 and that helped some. I like my 2020 KX450 significantly better than the 2023SR. I’m 6’3” and 185, slower 30+ B rider. I race 12-15 times a year. I’m comfortable on my 20KX but was looking for input on anyone that has made the move from green to blue. Has anyone went from the KX to YZF and if so what up? 

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quadzrulebro 6/21/2023 3:23pm
6/21/2023 3:23pm

At your height I think you’ll feel cramped on the YZ.  I’m the same height as you and that’s how I felt on my friend’s Yamaha.  Did you try switching to the softer hitting coupler yet?

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280driver
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280driver 6/21/2023 3:40pm
6/21/2023 3:40pm

What do you think the YZF will do better/differently?  Ive heard/read nothing but great things about the SR.  Maybe you can make some changes to make it suit you better.

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tschweitzer622 6/21/2023 3:59pm
6/21/2023 3:59pm
280driver wrote:
What do you think the YZF will do better/differently?  Ive heard/read nothing but great things about the SR.  Maybe you can make some changes to make...

What do you think the YZF will do better/differently?  Ive heard/read nothing but great things about the SR.  Maybe you can make some changes to make it suit you better.

Maybe I need to put some effort into it. Off the gate on a 50 on the rear you have to have her at 3/4 throttle to not stall/bog it. I talked to my local shop i take my engine & suspension work too. He said jump to a 51 on the rear and remap it. The 51 helped….I’m just having a hard time justifying 1K to Vortex after spending what I did on the bike. Just raced Amateur High Point and it completely rejustified why I don’t like the bike off the gate and on the track. Maybe I’m not fast enough to utilize the power. I don’t know what the issue is but after driving from St Louis to Pennsylvania and only race 2 motos with shitty gates I’m done with it. 

tschweitzer622 6/21/2023 4:01pm
6/21/2023 4:01pm
quadzrulebro wrote:
At your height I think you’ll feel cramped on the YZ.  I’m the same height as you and that’s how I felt on my friend’s Yamaha...

At your height I think you’ll feel cramped on the YZ.  I’m the same height as you and that’s how I felt on my friend’s Yamaha.  Did you try switching to the softer hitting coupler yet?

I have not, the SR is specially mapped separate from the normal 450. I probably have not put enough effort into it. I appreciate your feedback. 

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centralcalmx 6/21/2023 4:43pm
6/21/2023 4:43pm

I’m going the other way.

had a 19 kx450 went to a 21 yz450.

now have a deposit on the 24 Kawi.

6’ 4” the Kawis seem to just fit me better.

 

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CBE
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CBE 6/21/2023 5:11pm
6/21/2023 5:11pm
280driver wrote:
What do you think the YZF will do better/differently?  Ive heard/read nothing but great things about the SR.  Maybe you can make some changes to make...

What do you think the YZF will do better/differently?  Ive heard/read nothing but great things about the SR.  Maybe you can make some changes to make it suit you better.

tschweitzer622 wrote:
Maybe I need to put some effort into it. Off the gate on a 50 on the rear you have to have her at 3/4 throttle...

Maybe I need to put some effort into it. Off the gate on a 50 on the rear you have to have her at 3/4 throttle to not stall/bog it. I talked to my local shop i take my engine & suspension work too. He said jump to a 51 on the rear and remap it. The 51 helped….I’m just having a hard time justifying 1K to Vortex after spending what I did on the bike. Just raced Amateur High Point and it completely rejustified why I don’t like the bike off the gate and on the track. Maybe I’m not fast enough to utilize the power. I don’t know what the issue is but after driving from St Louis to Pennsylvania and only race 2 motos with shitty gates I’m done with it. 

If you are comfortable on the 20 kx450, simply swap the ecu from one bike to the other. The only other engine difference is the exhaust. The porting is not significant. Suspension-valving is slightly stiffer on the SR. PC does have inserts for the exhaust but i don’t know if they fit the SR ti-6. Also, PC can remap the stock ecu. I have done 3rd gear starts. If it is bogging in second something isn’t right. RPM obviously has to be up and maintained but it really shouldn’t bog or hesitate. There was a fuel pump recall on certain bikes.

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cmotodad
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cmotodad 6/21/2023 6:39pm
6/21/2023 6:39pm

My bike is a 20 KX450. Have ridden the YZ and I personally like the stable KX chassis. The sr motor is quite good on the bike I rode. JM.02

HarrowDrag 6/21/2023 9:42pm
6/21/2023 9:42pm

I'm all ears on this...

Have a 22 KX and can't find that sweet spot

Came off a YZ.

Love the chassis of the KX,harder I push it the better it reacts..slow to break traction.

YZ was aggressive at 51 teeth and felt like it kept front juuuust high enough to not feel confident 

Pondering going to 52 on the rear?

Eager to try keefers map he suggested in his review

Think I'll give 52 a try and then drag it to a dealer and have the mapping done.

 

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steelworker77 6/22/2023 7:33am
6/22/2023 7:33am
tschweitzer622 wrote:
Tossing around the idea of switching to a YZF 450. A few different random reasons…. Just bought a 2023 SR450 in December and I do not...

Tossing around the idea of switching to a YZF 450. A few different random reasons…. Just bought a 2023 SR450 in December and I do not Like the engine or ECU, at all. Starts are fucking horrible off the gate. I’m not fast enough to justify re-mapping it. I was hoping the amount I spent on it, it would be ready to race. I switched the rear to a 51 and that helped some. I like my 2020 KX450 significantly better than the 2023SR. I’m 6’3” and 185, slower 30+ B rider. I race 12-15 times a year. I’m comfortable on my 20KX but was looking for input on anyone that has made the move from green to blue. Has anyone went from the KX to YZF and if so what up? 

Man that's funny I was at that race too and entered in 30B.    I actually left after practice after seeing how far down In the race order we were and how shitty the track was in practice.  

I'm on a 21 Kx450 and have zero issues pulling starts.  I am on a 51 as well.   Have your stock ecu remapped.   They pull a lot of timing on the factory couplers.    The KX is a very vet friendly bike.      I have ridden the new YZ and was not impressed enough to make the switch.    The KX just does everything really good.   Not the best at anything but just a really well rounded forgiving bike.   

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ricko
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ricko 6/22/2023 10:23am
6/22/2023 10:23am

While I don't have a SR I have a 23 kawi 450 and I can hold it 3/4- full throttle on the start and its a rocket, i feel like you arent revved out enough, put the launch control on, get up on the front and twist it till its damn near rev limiter. i am on a 51 rear sprocket 

mx_phreek 6/22/2023 10:45am
6/22/2023 10:45am

Lol the SR’s having great engines

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