Jump to content
Sign in to follow this  

YZ250FX More Power!

Recommended Posts

I recently got a steal on a 250FX this past winter after coming off a 2014 Husaberg TE250. I've always wanted to try one out racing after hearing good things and this one just landed in my lap. 

I've raced it in two haresrambles now. 2nd in the first one and 3rd this past weekend, which was better than I expected as it was a very fast wide open type of course with some MX mixed in. So to the quick point as more often than not, I get going way too long. 

How have people gotten more power out of this bike? It's great, but I want it to come on harder when I get on it. As it sits right now, I have to really work it and feather the clutch to make it get going in a hurry. I'm not a big fan of just throwing money at a bike without knowing exactly how it will affect it. So at this time, it has the standard off road stuff, plus a full Rekluse 3.0. Motor is stock and it has the stock pipe on it. 

I rode a Very fast buddy's KX450 that is setup for NEPG enduros and I couldn't believe how quick it was. When I wanted to go, it WENT; Like putting myself in ludicrous speed for short bursts of time. So that has kind of infected my brain and I'm thinking a possible change to a KTM 450XC-F (2017 version) next season.

I'm pretty fond of how the FX handles though, so I've thought about the following items. 1- 269cc kit. Does this have a large improvement? How is the reliability? 2- Dr.D full exhaust system. They're a sponsor so I'd go with them, but I haven't seen too many people running Dr.D on the FX. 

Any thoughts? 

Share this post


Link to post
Share on other sites

Nothing is going to make it feel like a 450.  I came from a 2011 350, which is the WEAKEST of them all, and it had way more power than the fx does.  Down low, mid, up high (especially up high). 

A thread from davbrucas on the motor derick harris built for him.  Read it and decide how much power (money) you want.

 

Share this post


Link to post
Share on other sites

Do you have the GYTR tuner? I'd start with just putting the hard hitting map on it. Any big gains in power are going to be big loss in wallet.

Edited by Kosmic
  • Like 1

Share this post


Link to post
Share on other sites

I find my YZ250FX under powered too.  I prefer riding my YZ450FX for exactly the reasons you describe.  After getting off the 450, I can't believe how anemic the 250FX is, especially when I want to loft the front wheel.  

  • Like 1

Share this post


Link to post
Share on other sites
1 hour ago, MidlifeCrisisGuy said:

I find my YZ250FX under powered too.  I prefer riding my YZ450FX for exactly the reasons you describe.  After getting off the 450, I can't believe how anemic the 250FX is, especially when I want to loft the front wheel.  

 
 

I've heard good things about the motor on the 450FX, but the weight of the thing has me questioning even considering it. 

KTM no gas weight: 223.5lbs

450FX no gas weight: 249.4lbs (26lbs heavier than the KTM!)

Yeah, you can reduce the weight a bit with the lithium battery and possibly a different exhaust, but that would only get you 5lbs at the very most. If Yamaha puts the 18 450FX on a diet and gets it down around 230lbs, one would be sitting in my garage once they release. But, seeing how they flow down updates from the MX version to the offroad versions, I do not see this happening anytime soon. 

Edited by MyersAvionics

Share this post


Link to post
Share on other sites

Buy a 450, no sense wasting money on the 250 for little return.

Start by going up one tooth on the rear sprocket. Maybe load the aggressive map on it. Try a quick turn throttle. 

Full exhaust is a waste unless you are looking to lose weight, quiet it down or get a spark arrestor.

Share this post


Link to post
Share on other sites
5 hours ago, MyersAvionics said:

I've heard good things about the motor on the 450FX, but the weight of the thing has me questioning even considering it. 

KTM no gas weight: 223.5lbs

450FX no gas weight: 249.4lbs (26lbs heavier than the KTM!)

Yeah, you can reduce the weight a bit with the lithium battery and possibly a different exhaust, but that would only get you 5lbs at the very most. If Yamaha puts the 18 450FX on a diet and gets it down around 230lbs, one would be sitting in my garage once they release. But, seeing how they flow down updates from the MX version to the offroad versions, I do not see this happening anytime soon. 

Ride a 450FX before you go all crazy talking about weight. It does not feel that heavy, just like the 250 does not feel like it's weight. 

  • Like 1

Share this post


Link to post
Share on other sites
1 hour ago, ckny said:

Ride a 450FX before you go all crazy talking about weight. It does not feel that heavy, just like the 250 does not feel like it's weight. 

I hear ya, but when I first got back into riding, I got a 2012 WR450F thinking I wasn't going to race too much. Instead, it became my main race bike after I discovered how fun off road racing is. That bike had to be about 260lbs without fuel. It didn't feel "that" heavy while riding it, but as soon as you got out of shape a little bit it would toss ya because that extra weight carried a lot of momentum. 

The other part of it is picking the darned thing up. 25lbs doesn't sound like a lot of weight until you're picking it up with it caked in mud! Still, though, I'm looking at the Yamaha website to find a demo day to try the 450FX out at some point. 

Share this post


Link to post
Share on other sites
12 hours ago, MyersAvionics said:

I've heard good things about the motor on the 450FX, but the weight of the thing has me questioning even considering it. 

KTM no gas weight: 223.5lbs

450FX no gas weight: 249.4lbs (26lbs heavier than the KTM!)

Yeah, you can reduce the weight a bit with the lithium battery and possibly a different exhaust, but that would only get you 5lbs at the very most. If Yamaha puts the 18 450FX on a diet and gets it down around 230lbs, one would be sitting in my garage once they release. But, seeing how they flow down updates from the MX version to the offroad versions, I do not see this happening anytime soon. 

I haven't ridden a new 450 XCF.  I'm not a racer.  I can't dispute that the YZ450FX feels heavier than the YZ250FX. 

I can say these things

- the 450FX handles extremely well

- it feels heavier in 1st, mostly due to engine braking.  It would be nice if 1st was closer to 2nd.

- 7 pounds comes off with Shorai battery, remove kick starter, remove kickstand, lighter/better $50 footpegs and a few other things

- the KTM doesn't have a lighting coil or a skid plate and the KTM handguards are junk

- the FX engine is super tunable and runs really well with the stock map.  Power and control everywhere.  Perfect woods engine.

- you don't have to spend $$$ getting the FX suspension to work

- the FX is stone reliable

- the FX doesn't seem to overheat and the clutch works well

I think the price, reliability, suspension, engine and better cooling make it a great bike as it is.

Why don't you just buy a 450XCF ?

 

  • Like 1

Share this post


Link to post
Share on other sites
5 hours ago, MyersAvionics said:

I hear ya, but when I first got back into riding, I got a 2012 WR450F thinking I wasn't going to race too much. Instead, it became my main race bike after I discovered how fun off road racing is. That bike had to be about 260lbs without fuel. It didn't feel "that" heavy while riding it, but as soon as you got out of shape a little bit it would toss ya because that extra weight carried a lot of momentum. 

The other part of it is picking the darned thing up. 25lbs doesn't sound like a lot of weight until you're picking it up with it caked in mud! Still, though, I'm looking at the Yamaha website to find a demo day to try the 450FX out at some point. 

I had a 2012 WR450F.  Stock and lightened 25 pounds.  The YZ450FX handles way, way better than the stock WR.  Miles better.  It is also quite a bit better than my lightened WR was, even though it had a lot of the same setup.  The reverse engine must make it feel lighter and the FX engine is tuned better for woods.

Share this post


Link to post
Share on other sites
7 hours ago, ckny said:

Start by going up one tooth on the rear sprocket. Maybe load the aggressive map on it. Try a quick turn throttle. 

Full exhaust is a waste unless you are looking to lose weight, quiet it down or get a spark arrestor.

In spite of what everyone calls a super low 1st gear ratio, the 450FX does 38 MPH wound out in 1st gear. 

I like my engine spinning a bit when I'm climbing hills and going through tight technical stuff.  I hate 4 strokes when they are just ticking along a bit over idle.

I went from 13 to 12 on the CS and it seems perfect in tight woods.  2nd gear is fantastic for climbing hills and you have a super low 1st to drop into if you get into trouble.  And it is great for picking your way through really tight and technical stuff.   Otherwise I'm in 2nd or higher 90% of the time.  It never stalls with this gearing.  Like never. 

People say that 12/50 is too low on a 450F, that it will just spin or wheelie, but with throttle and clutch control it works great.

I found that 12/51 or even 53 really woke up the 250FX, but it is still in need of more power.  Revs only go so far with the stock engine.  I just find there are too many times I'm WOT wishing for more or wanting more snap to throw the bike around with.  The 450FX has just the right amount of power and snap for my liking.   The 250FX engine feels like a trials bike engine after getting off the YZ450FX.

Right now I prefer the 450FX to the 250FX.  The 250FX is a great bike, but the 450FX just trumps it everywhere.

 

 

Edited by MidlifeCrisisGuy

Share this post


Link to post
Share on other sites
7 hours ago, ckny said:

Full exhaust is a waste unless you are looking to lose weight, quiet it down or get a spark arrestor.

I'd like to know what difference aftermarket exhaust makes on the 450FX engine braking.

Share this post


Link to post
Share on other sites
3 hours ago, racer651 said:

Cylinder works 270 kit is a pretty good bang for the buck. 

I've really been debating that one. Have you noticed any extra heat? What kind of terrain do you ride?

Share this post


Link to post
Share on other sites
15 hours ago, MidlifeCrisisGuy said:

I can't believe how anemic the 250FX is, especially when I want to loft the front wheel.  

Sure the 250 might feel weak compared to the 450, but getting the wheel up is more your technique than the bike. I get my 250FX front wheel up in 4th to avoid surprise trail trash on the fast stuff, and constantly do in 3rd as well in the slower single track. So the bike definitely does not have problems 'getting it up'.

  • Like 2

Share this post


Link to post
Share on other sites
1 hour ago, Goatse said:

Sure the 250 might feel weak compared to the 450, but getting the wheel up is more your technique than the bike. I get my 250FX front wheel up in 4th to avoid surprise trail trash on the fast stuff, and constantly do in 3rd as well in the slower single track. So the bike definitely does not have problems 'getting it up'.

You've got a point about technique and seating position and engine map matter too.  I've been meaning to play around with these in order to make it wheelie better.  But as it sits now, it is very lethargic and front end heavy.  I can get it to wheelie but it takes a lot of body English.  

My 450FX is set up identically and it just comes up, no English needed.  Takes a lot less effort which adds up over the day.

What is the most wheelie aggressive map for the 250FX ?

Share this post


Link to post
Share on other sites

My favourite map is the GYTR hard hitting map. I feel it's the best all around, and surprisingly enough the smoothest off idle as well.

As for the body English, I'd imagine that's it. Even with just the tiniest fork bump, it really doesn't take much power to get any dirtbike to wheelie. With timing the fork rebound right in time with the throttle, even our little TTR110 can do wheelies in 2nd gear.

  • Like 1

Share this post


Link to post
Share on other sites

I have never had an issue getting the front end up on my FX. Lug in 2nd, comes up, low/mid throttle in 3rd, it comes up. 195lbs without gear, nowhere near pro rider.

  • Like 1

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Reply with:

Sign in to follow this  

×
×
  • Create New...