Yamaha Discussions about Yamaha ATVs.

Yfz 450 cranking problem

Thread Tools
 
Search this Thread
 
  #1  
Old 08-05-2016, 01:03 AM
NelsonLawler's Avatar
Weekend Warrior
Thread Starter
Join Date: Jul 2016
Posts: 11
Likes: 0
Received 0 Likes on 0 Posts
Default Yfz 450 cranking problem

Yfz is cranking super slow almost like it doesnt have power to rurn the motor over it will crank once extremely slow then twice amd sometimes a couple times more then it will just click have tried everything I put a new battery new relay new starter new stator checked the timing and the crank and the valves and I have no idea wtf is going on! I brought it to the dealer and they replaced all of the and I'm about 600 dollor into it already and my headlights don't work once I finally get it going it seems to run great. Please help!!!
 
  #2  
Old 08-05-2016, 02:06 AM
merryman's Avatar
Elite Pro Rider
Join Date: Oct 2013
Location: Lancaster England
Posts: 6,862
Received 301 Likes on 295 Posts
Default

Sounds like a flat battery, did you charge it up? Some new batteries are flat when they come and have to be charged for an hour or so. If it isn't just that I would take it back to the dealer and tell them they haven't fixed it. Seems like they are not very good though, as they have been "throwing parts at it" instead of testing things out.
 
  #3  
Old 08-05-2016, 02:14 AM
NelsonLawler's Avatar
Weekend Warrior
Thread Starter
Join Date: Jul 2016
Posts: 11
Likes: 0
Received 0 Likes on 0 Posts
Thumbs up

Originally Posted by merryman
Sounds like a flat battery, did you charge it up? Some new batteries are flat when they come and have to be charged for an hour or so. If it isn't just that I would take it back to the dealer and tell them they haven't fixed it. Seems like they are not very good though, as they have been "throwing parts at it" instead of testing things out.
I charged the battery and the previous battery was good too. It is at the dealer rn I'm trying to get is back and fix it myself because I'm 19 and don't make much over minimum wage so don't have to much money to throw at at and the 100 dollor a hour is killing me thanks for the reply tho!
 
  #4  
Old 08-05-2016, 09:10 AM
Scooter86's Avatar
Extreme Pro Rider
Knows Old ATV Questions!
Join Date: Sep 2003
Posts: 5,127
Likes: 0
Received 3 Likes on 3 Posts
Default

Take apart the starter/kill switch assembly. It has a drain hole or 2 in the bottom, but gets gunked up over time. I have had similar issues and on occasion the contacts have been dirty enough to cause poor starting. The other thing I do is hack that battery box up a bit and fit a larger battery in. You may need to fab up a bar to hold the batt down as well. Or go with one of those new lithium iron or whatever batts. The stocker is the minimum size for weight restriction, but struggles when you add anything that makes it harder to start.
 
  #5  
Old 08-05-2016, 12:42 PM
NelsonLawler's Avatar
Weekend Warrior
Thread Starter
Join Date: Jul 2016
Posts: 11
Likes: 0
Received 0 Likes on 0 Posts
Default

Thanks for the reply scooter86 I will go tell them today and try it out.
 
  #6  
Old 08-09-2016, 09:32 PM
NelsonLawler's Avatar
Weekend Warrior
Thread Starter
Join Date: Jul 2016
Posts: 11
Likes: 0
Received 0 Likes on 0 Posts
Default

Originally Posted by Scooter86
Take apart the starter/kill switch assembly. It has a drain hole or 2 in the bottom, but gets gunked up over time. I have had similar issues and on occasion the contacts have been dirty enough to cause poor starting. The other thing I do is hack that battery box up a bit and fit a larger battery in. You may need to fab up a bar to hold the batt down as well. Or go with one of those new lithium iron or whatever batts. The stocker is the minimum size for weight restriction, but struggles when you add anything that makes it harder to start.
The dealer thinks the problem is that the starter can't handle the mods is this possible? I have a brand new started but it's not heavy duty?
 
  #7  
Old 08-13-2016, 07:55 AM
Scooter86's Avatar
Extreme Pro Rider
Knows Old ATV Questions!
Join Date: Sep 2003
Posts: 5,127
Likes: 0
Received 3 Likes on 3 Posts
Default

What mods do you have? I have run them with 13:1 comp and a cam and the stock starter would wind it right up. Dead engine xc starts, so we ran larger batteries. That is just extra cranking amps though, not more voltage.
 
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
donw
Yamaha
17
06-20-2016 03:19 PM
04 Preddy
Polaris Ask an Expert! In fond memory of Old Polaris Tech.
3
06-18-2016 08:32 AM
Zephead98
Polaris
8
05-31-2016 01:26 AM
Thalowin
Chinese Quads
0
05-19-2016 09:45 AM
bodatiouskid
Polaris
4
05-15-2016 01:24 PM

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 


Quick Reply: Yfz 450 cranking problem



All times are GMT -5. The time now is 05:56 AM.