2018 Yamaha YZ450F stops mid moto

rryker
Posts
86
Joined
6/15/2015
Location
Olney, IL US
7/21/2020 8:14am
Anyone out there that has ever had this happen before? 2018 Yamaha YZ450F. Starts right up, runs fine, mid moto the bike dies, pull off track and starts right back up. This happen two weeks ago a couple of different times so I pulled the kill switch off of it. Thought it was fixed as it was ridden 6 different times since then with no issues, doing 2 20 minute moto's each day along with working on starts and then today it happens again. Any thoughts???
|
MZ193
Posts
938
Joined
12/14/2018
Location
IT
7/21/2020 8:25am
Those yamis have a ton of problems.
I wouldn't use a bike that randomly stops mid-moto, imagine it stopping right on the face of a jump.
No, thanks, i'm selling the bike and getting a kawi/ktm.
2
27
7/21/2020 8:36am
I'd keep a finger on the clutch if i were you. You may be able to have a dealer plug it in and check for codes/ run diagnostics.
cbarber
Posts
198
Joined
6/6/2014
Location
Atwater, MN US
Fantasy
2209th
7/21/2020 8:54am
MZ193 wrote:
Those yamis have a ton of problems. I wouldn't use a bike that randomly stops mid-moto, imagine it stopping right on the face of a jump...
Those yamis have a ton of problems.
I wouldn't use a bike that randomly stops mid-moto, imagine it stopping right on the face of a jump.
No, thanks, i'm selling the bike and getting a kawi/ktm.
do you ever have anything helpful to add?
Donkey Kong
Posts
389
Joined
6/25/2020
Location
New England, MA US
7/21/2020 9:04am
MZ193 wrote:
Those yamis have a ton of problems. I wouldn't use a bike that randomly stops mid-moto, imagine it stopping right on the face of a jump...
Those yamis have a ton of problems.
I wouldn't use a bike that randomly stops mid-moto, imagine it stopping right on the face of a jump.
No, thanks, i'm selling the bike and getting a kawi/ktm.
I think it's more along the lines of that Yamaha sells so many of those bikes that you see more problems.
2
2

The Shop

Talisker
Posts
888
Joined
10/25/2018
Location
Houston, TX US
7/21/2020 9:07am Edited Date/Time 7/21/2020 12:01pm
Clogged up fuel injectors maybe??? I always purchase the Twin Air filters that go inside the fuel tank for this reason. You don’t realize the fine dust particles that accumulate in your gas can.
Also check to make sure the fuel line is not pinched or twisted. It sounds simple but I have had this happen before.
3
SKIDLID
Posts
971
Joined
4/9/2013
Location
Fairmont, MN US
Fantasy
918th
7/21/2020 10:40am
My 250yzf did this a few races recently. Mine was the coil had a loose connector on the end of it.
1
pelosi826
Posts
63
Joined
12/5/2013
Location
Johnstown, NY US
Fantasy
2772nd
7/21/2020 11:34am
I've had this happen to my 18 at a sand track. Getting bad starts with close to full gate, you get a lot of roost from 450s. The roost goes right into the airbox, the way the shroud design is. The air filter gets dirty easily. Had to pull off at the end of the moto from mine dying on me too.
2
Handy_andy_85
Posts
74
Joined
6/15/2020
Location
Wheatfield, IN US
Fantasy
1264th
7/21/2020 11:42am
The last time i had something similar it was a plugged vent on the gas cap. Sometimes the metal ball in the one way check valve corrodes and blocks flow. Or dirt can plug the rubber vent line. Take the gas cap of and make sure you can suck air through the vent line, when you flip the cap upside down the air flow should stop.
2
TbonesPop
Posts
3452
Joined
1/26/2010
Location
Gilbert, AZ US
Fantasy
360th
7/21/2020 11:50am
rryker wrote:
Anyone out there that has ever had this happen before? 2018 Yamaha YZ450F. Starts right up, runs fine, mid moto the bike dies, pull off track...
Anyone out there that has ever had this happen before? 2018 Yamaha YZ450F. Starts right up, runs fine, mid moto the bike dies, pull off track and starts right back up. This happen two weeks ago a couple of different times so I pulled the kill switch off of it. Thought it was fixed as it was ridden 6 different times since then with no issues, doing 2 20 minute moto's each day along with working on starts and then today it happens again. Any thoughts???
Check vent line on gas cap. Sounds like you are restricting fuel flow to the engine
3
1
huutnanny
Posts
83
Joined
4/21/2019
Location
San Francisco, CA US
7/21/2020 1:40pm
I believe you can use your app to check for codes instead of taking it to the dealer.
2
redduk
Posts
55
Joined
12/7/2017
Location
Tucson, AZ US
7/21/2020 2:17pm
My 18 yz250f would do the same thing. Vent hose was plugged with dirt and old gas
2
Jack_Wagon
Posts
284
Joined
7/18/2011
Location
Conyers, GA US
7/21/2020 3:09pm
We had two 18 450s. We had the same problem with both bikes. I changed the stator, harness, pump, battery, kill switch, condenser, and starter relay. Never fixed it. That combined with the transmission lasting an average of 10 hours each left a bad taste for Yamahw 450s. Our 19 and 20 250s have been solid
MZ193
Posts
938
Joined
12/14/2018
Location
IT
7/21/2020 4:05pm
MZ193 wrote:
Those yamis have a ton of problems. I wouldn't use a bike that randomly stops mid-moto, imagine it stopping right on the face of a jump...
Those yamis have a ton of problems.
I wouldn't use a bike that randomly stops mid-moto, imagine it stopping right on the face of a jump.
No, thanks, i'm selling the bike and getting a kawi/ktm.
cbarber wrote:
do you ever have anything helpful to add?
Not if it's related to a 2014+ Yzf😂
11
SKIDLID
Posts
971
Joined
4/9/2013
Location
Fairmont, MN US
Fantasy
918th
7/21/2020 4:18pm
huutnanny wrote:
I believe you can use your app to check for codes instead of taking it to the dealer.
That’s how I found mine
1911
Posts
3999
Joined
4/2/2008
Location
LAS VEGAS, NV US
7/21/2020 4:54pm
MZ193 wrote:
Those yamis have a ton of problems. I wouldn't use a bike that randomly stops mid-moto, imagine it stopping right on the face of a jump...
Those yamis have a ton of problems.
I wouldn't use a bike that randomly stops mid-moto, imagine it stopping right on the face of a jump.
No, thanks, i'm selling the bike and getting a kawi/ktm.
cbarber wrote:
do you ever have anything helpful to add?
MZ193 wrote:
Not if it's related to a 2014+ Yzf😂
Not useful or funny.
4
TallonT911
Posts
559
Joined
10/31/2013
Location
Henderson, NV US
7/21/2020 5:10pm
I had a problem with my 16 cutting out after it got hot, would still run just cut out, so a little different than yours, but mine was the spark plug cap
TbonesPop
Posts
3452
Joined
1/26/2010
Location
Gilbert, AZ US
Fantasy
360th
7/21/2020 6:25pm
Jack_Wagon wrote:
We had two 18 450s. We had the same problem with both bikes. I changed the stator, harness, pump, battery, kill switch, condenser, and starter relay...
We had two 18 450s. We had the same problem with both bikes. I changed the stator, harness, pump, battery, kill switch, condenser, and starter relay. Never fixed it. That combined with the transmission lasting an average of 10 hours each left a bad taste for Yamahw 450s. Our 19 and 20 250s have been solid
We have (2) '18 YZ450Fs and both have been perfectly rock solid at +70 hours on each. No idea what was going on with yours.
NoMuff2Tuff
Posts
192
Joined
2/11/2015
Location
La Place, LA US
7/25/2020 10:09pm
This started happening to my neighbors 18 yzf450. Picked up the bike used in excellent condition with 5 original hours on it. Bike was solid for about 15-20 motos of practice then just started dying mid moto for no reason but would always start back right back up. Sometimes it would be fine for 2-3 days with no issues. Checked for loose connections, wire terminal corrosion etc but nothing obvious. Took it to Ponco Regional and it killed once in every moto in 450 C, cost him an overall and finished 2nd, was leading every moto. Finally his dad took it to a reputable shop, they ran test, showed a code and came to the conclusion the tip over sensor in the ECU was malfunctioning causing the problem. The shop even got Yamaha rep to get a new ECU free of charge. After the ECU replacement and no codes showing the bike ran fine at practice for 2 days, on the 3rd day it killed right before a jump face and lucky he was able to save it and not crash. The bike was traded in the next day for a 2020 yzf450 and so far this bike has been reliable.

Post a reply to: 2018 Yamaha YZ450F stops mid moto

The Latest