No compression on 2017 yz250f

finlay
Profile picture for user finlay
Posts
8
Joined
4/19/2020
Location
GB
finlay
Edited Date/Time 4/20/2020 7:59am
I just took my 2017 yz250f out for a normal ride round my local trail and everything seemed normal until the Engine all a sudden cut out. Then I went to start it up and there was no compression at all as I could kick it with my hand. This bike only had about 10-15 hours on it. Does anyone have any idea how to fix it or what it could be?
|
RENNERlicious
Profile picture for user RENNERlicious
Posts
34
Joined
5/16/2019
Location
Sacramento, CA, USA
RENNERlicious 4/19/2020 11:28am
4/19/2020 11:28am
finlay wrote:
I just took my 2017 yz250f out for a normal ride round my local trail and everything seemed normal until the Engine all a sudden cut...
I just took my 2017 yz250f out for a normal ride round my local trail and everything seemed normal until the Engine all a sudden cut out. Then I went to start it up and there was no compression at all as I could kick it with my hand. This bike only had about 10-15 hours on it. Does anyone have any idea how to fix it or what it could be?
Dropped a valve.
finlay
Profile picture for user finlay
Posts
8
Joined
4/19/2020
Location
GB
finlay 4/19/2020 12:21pm
4/19/2020 12:21pm
finlay wrote:
I just took my 2017 yz250f out for a normal ride round my local trail and everything seemed normal until the Engine all a sudden cut...
I just took my 2017 yz250f out for a normal ride round my local trail and everything seemed normal until the Engine all a sudden cut out. Then I went to start it up and there was no compression at all as I could kick it with my hand. This bike only had about 10-15 hours on it. Does anyone have any idea how to fix it or what it could be?
RENNERlicious wrote:
Dropped a valve.
Does this have anything to do with having no compression?
1
Paw Paw 271
Profile picture for user Paw Paw 271
Posts
3632
Joined
4/3/2013
Location
Benton, LA, USA
Paw Paw 271 4/19/2020 12:49pm
4/19/2020 12:49pm
Yes it does. You have a real issue at hand. It has for sure jumped cam timing and most likely dropped a valve as already stated.
Time for a tear down.

Paw Paw
1
finlay
Profile picture for user finlay
Posts
8
Joined
4/19/2020
Location
GB
finlay 4/19/2020 1:59pm
4/19/2020 1:59pm
Paw Paw 271 wrote:
Yes it does. You have a real issue at hand. It has for sure jumped cam timing and most likely dropped a valve as already stated...
Yes it does. You have a real issue at hand. It has for sure jumped cam timing and most likely dropped a valve as already stated.
Time for a tear down.

Paw Paw
Ahh not so great news then. Have you got any idea how the chain could of got that loose as it is a fairly new bike with low hours on it?

The Shop

See All »
project racer 4/19/2020 2:57pm
4/19/2020 2:57pm
Check the cam chain guides. Maybe jumped timed and bent a valve.
1
DynoDan22
Profile picture for user DynoDan22
Posts
769
Joined
9/7/2011
Location
Victorville, CA, USA
DynoDan22 4/19/2020 3:38pm
4/19/2020 3:38pm Edited Date/Time 4/19/2020 3:39pm
Flags at half mast for that motor. She needs to be torn down and inspected.
2
foreman52
Profile picture for user foreman52
Posts
633
Joined
5/29/2018
Location
CA
foreman52 4/19/2020 6:50pm
4/19/2020 6:50pm
Does not look/sound good man. Myself and a buddy of mine had valve issues in our 16 & 17’s but they never actually dropped like it sounds with yours. I also had my 18 Yami 450 jump the cam chain with no explanation at all. Might be better to cut your loss now and sell it as is before tying $3-$4K up in parts and labour. Keep us updated.
1
Paw Paw 271
Profile picture for user Paw Paw 271
Posts
3632
Joined
4/3/2013
Location
Benton, LA, USA
Paw Paw 271 4/19/2020 6:54pm
4/19/2020 6:54pm
Cam chain tensioner may have failed.

Paw Paw
4
lostboy819 4/19/2020 9:01pm
4/19/2020 9:01pm
finlay wrote:
Ahh not so great news then. Have you got any idea how the chain could of got that loose as it is a fairly new bike...
Ahh not so great news then. Have you got any idea how the chain could of got that loose as it is a fairly new bike with low hours on it?
Fairly new with low hours is a pretty broad term for a 2017. How many hours and how much maintenance has been done to it ? but the bottom line is its gonna have to be torn down. Sad
1
rongi#401
Profile picture for user rongi#401
Posts
1635
Joined
6/20/2016
Location
southern, CA, USA
rongi#401 4/19/2020 9:22pm
4/19/2020 9:22pm
She will live again
1
finlay
Profile picture for user finlay
Posts
8
Joined
4/19/2020
Location
GB
finlay 4/20/2020 1:25am
4/20/2020 1:25am
finlay wrote:
Ahh not so great news then. Have you got any idea how the chain could of got that loose as it is a fairly new bike...
Ahh not so great news then. Have you got any idea how the chain could of got that loose as it is a fairly new bike with low hours on it?
lostboy819 wrote:
Fairly new with low hours is a pretty broad term for a 2017. How many hours and how much maintenance has been done to it...
Fairly new with low hours is a pretty broad term for a 2017. How many hours and how much maintenance has been done to it ? but the bottom line is its gonna have to be torn down. Sad
Yeh not so good news. The reason it has low hours is because it has been sat in a container for a couple of years we only started riding it about Christmas time. But we did all the regular maintenance like changing the oil.
finlay
Profile picture for user finlay
Posts
8
Joined
4/19/2020
Location
GB
finlay 4/20/2020 1:31am
4/20/2020 1:31am
foreman52 wrote:
Does not look/sound good man. Myself and a buddy of mine had valve issues in our 16 & 17’s but they never actually dropped like it...
Does not look/sound good man. Myself and a buddy of mine had valve issues in our 16 & 17’s but they never actually dropped like it sounds with yours. I also had my 18 Yami 450 jump the cam chain with no explanation at all. Might be better to cut your loss now and sell it as is before tying $3-$4K up in parts and labour. Keep us updated.
were gonna tear it down and try to diagnose what has happened to the engine and then try to decide weather it is Savable or if it’s gonna have to go.
BobPA
Profile picture for user BobPA
Posts
8330
Joined
10/31/2013
Location
USA
BobPA 4/20/2020 7:59am
4/20/2020 7:59am
foreman52 wrote:
Does not look/sound good man. Myself and a buddy of mine had valve issues in our 16 & 17’s but they never actually dropped like it...
Does not look/sound good man. Myself and a buddy of mine had valve issues in our 16 & 17’s but they never actually dropped like it sounds with yours. I also had my 18 Yami 450 jump the cam chain with no explanation at all. Might be better to cut your loss now and sell it as is before tying $3-$4K up in parts and labour. Keep us updated.
finlay wrote:
were gonna tear it down and try to diagnose what has happened to the engine and then try to decide weather it is Savable or if...
were gonna tear it down and try to diagnose what has happened to the engine and then try to decide weather it is Savable or if it’s gonna have to go.
Post pictures. We can help give you a pretty good idea of what went wrong, and what needs to be fixed.

Post a reply to: No compression on 2017 yz250f