More info on YZ450FX

How hot a TE runs depends where you set the power valve, what thickness your base gasket is, how it is jetted, what fuel you are using and which map you are using.  My friend has a 2015 TE300.  We had to lend him water once.

Edited by MidlifeCrisisGuy

It turns out that the muffler is a very important part of tuning a YZ450FX.  This article on the 2016 WR450F explains why.  http://dirtbiketest.com/bike-tests/2016-yamaha-wr450f/

 

What gear are you in when you stall ?

Usually 1st & 2nd slow technical riding (think going over a log on the pegs than crawling along setting up for the next obstacle), I find it flames out easily and feels like it has very little flywheel, spools up in a hurry. Some of my struggles are just getting used to the bike. What is the relevance of the Wr article? It has a totally different muffler, the fx is the F mufler. I have a q4 on it now but performance is about the same. Got a tuner on the way.

The 500 XC-W is an excellent bike. I thought it was one of the better four strokes I've rode in technical terrain.

However, the suspension is soft with open cartridge forks and you have a lot less RPM to work with vs the 450FX. Rev limiter is like 9000 RPM on the 500 while I believe the Yamaha 450 is 11,500 RPM.

Don't expect the long overrev of a 450 with the 500. The 500 is very torquey but gives up top end horsepower to the 450.

If you want stiffer suspension, the Husky 501 has the 4CS forks which are stiffer. Although reviews on those forks have not been that great.

Just an observation.

Just got a Fe 501s a month ago....love it!!!

What is the relevance of the Wr article?

 

 

None that I can see.  Everyone knows the WR muffler is restrictive, and it has nothing at all to with the FX, as the FX and the F use a free flow race exhaust.

Usually 1st & 2nd slow technical riding (think going over a log on the pegs than crawling along setting up for the next obstacle), I find it flames out easily and feels like it has very little flywheel, spools up in a hurry. Some of my struggles are just getting used to the bike. What is the relevance of the Wr article? It has a totally different muffler, the fx is the F mufler. I have a q4 on it now but performance is about the same. Got a tuner on the way.

 

More backpressure takes the edge off the engine.  If it is too much for you, get a WR exhaust system and put it on or use a muffler with more backpressure.   Are you running a spark arrestor in your Q4 ?  How about the quiet insert ?

 

The other things to do are to check the idle mixture with the FI tool, check the idle RPM and gear it down.

 

If you are new to riding a big 4 stroke, that will have something to do with it too.  You shouldn't be stalling in 2nd gear.  Drop to 1st if you need to go that slow.  Always cover the clutch.  Try to learn to not shut the throttle off all the way, ever.   Learn to keep it cracked just a little bit and use the clutch.  

 

My riding group went through stalling issues with the FI WR450F and the YZ450F.  After some tuning and learning to ride them, we rarely stall.

 

FWIW, according to the reviews, some bikes are way more stall prone than the YZ450FX.

Edited by MidlifeCrisisGuy

None that I can see.  Everyone knows the WR muffler is restrictive, and it has nothing at all to with the FX, as the FX and the F use a free flow race exhaust.

 

A more restrictive exhaust takes the edge off, on the bottom end especially.  Read the article.   Gets rid of the really strong throttle response that you guys complain about when you gear these bikes down.  Remember, the spinning and looping you are worried about in 1st gear.

Edited by MidlifeCrisisGuy

That's funny.

 

And irrelevant to tuning the FX. 

More backpressure takes the edge off the engine.  If it is too much for you, get a WR exhaust system and put it on or use a muffler with more backpressure.   Are you running a spark arrestor in your Q4 ?  How about the quiet insert ?

 

The other things to do are to check the idle mixture with the FI tool, check the idle RPM and gear it down.

 

If you are new to riding a big 4 stroke, that will have something to do with it too.  You shouldn't be stalling in 2nd gear.  Drop to 1st if you need to go that slow.  Always cover the clutch.  Try to learn to not shut the throttle off all the way, ever.   Learn to keep it cracked just a little bit and use the clutch.  

 

My riding group went through stalling issues with the FI WR450F and the YZ450F.  After some tuning and learning to ride them, we rarely stall.

 

FWIW, according to the reviews, some bikes are way more stall prone than the YZ450FX.

Not new to big bore thumpers, in the last 5 years I've owned a kx450, 350sxf, 520mxc, husaberg fx450 70 degree, and currently own an rmz450 along with the Yammi, the fx flames out as easy as any of the mx bikes I've owned. Like I said haven't dialed it in with the tuner yet, has the quiet tip and arrester in, no difference. Feels like it has no more flywheel weight than my rmz. Has any found different mapping helpful?

Yes, and also gear it down some. Go to a 52 in the rear.

Edited by RMK800

I have a 51 on it, maybe I'll go up one. Just to clarify I'm not complaining about the bike, I bought it to do turkey runs and race gp's, where the lack of flywheel feeling and explosive power is not an issue. I also don't stall it every time I ride tight single track on it, but it does seem to flame out a bit easier than other woods oriented thumpers I've ridden. The topic of the thread was comparing 3 different bikes, I own two of them so I'm simply sharing my experiences so far.

Playing around with the power tuner will help a ton.  A good place to start is the recommended curves on their website:

 

https://www.shopyamaha.com/product/details/gytr-power-tuner

 

I started with the "Hard-pack conditions." This ended up being a bit soft on the bottom end so I just modified it from there until I got it to my liking.

 

A rekluse helps a ton too ;-)

I hate to do it but every big 4 stk I've owned I put a rekluse on them. Soon as I finished setting mine up I broke my thumb. I have the tuner and am ready to go but 5 more weeks.

 I also don't stall it every time I ride tight single track on it, but it does seem to flame out a bit easier than other woods oriented thumpers I've ridden.

 

I'd try bumping up the idle speed just a hair and see if that helps.  In my experience the Yamaha's like just a bit higher idle but that was on carbed bikes.

I wonder if that would work like a heavy flywheel, there was a lot of chatter about the Rekluse z-start and zsp clutches doubling as a flywheel weight but in the end dispelled because it counter rotates in relation to the motor as well as not being directly connected to the crank. I guess it can't hurt as its all rotating mass.

I'd try bumping up the idle speed just a hair and see if that helps.  In my experience the Yamaha's like just a bit higher idle but that was on carbed bikes.

That will be my first mod, cheapest first.

Irony: the guy constantly complaining about how heavy a bike is that he's never ridden, posting a link to a part that will make the bike heavier.

 

Suspension and and engine function matter more than weight.

I wonder if that would work like a heavy flywheel, there was a lot of chatter about the Rekluse z-start and zsp clutches doubling as a flywheel weight but in the end dispelled because it counter rotates in relation to the motor as well as not being directly connected to the crank. I guess it can't hurt as its all rotating mass.

 

It is designed especially to be like a FWW.  Some bikes don't have room to add weight to the FW, so they add it to the clutch basket instead.

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