one piston black one not?? PLEEZ HELP - Yamaha ATV Forum
LinkBack Thread Tools Display Modes
post #1 of 4 Old 01-30-2017, 12:57 AM Thread Starter
TRU211's Avatar
Join Date: Dec 2015
Location: Az
Posts: 46
one piston black one not?? PLEEZ HELP

so i removed my head and see that only one piston looks black brown and the other piston still looks new? what wud cause this?it was a fresh build. and then fast forward to a week later took it for another ride and suffered DETONATION on the same burnt looking piston. i had barely realized this when i was going thru some pics.I am currently rebuiding the motor and dont want to have the same issue.what cud have went wrong with the first build??
TRU211 is offline  
Sponsored Links
post #2 of 4 Old 01-30-2017, 12:09 PM
Join Date: Dec 2016
Posts: 66
Check your plug. Sounds like you're running rich

Sent from my iPad using Tapatalk
Nowinski02 is offline  
post #3 of 4 Old 01-30-2017, 12:35 PM
Crowd Control
diggerzmound's Avatar
Join Date: Oct 2002
Location: Nebraska
Posts: 8,524
Send a message via AIM to diggerzmound Send a message via Yahoo to diggerzmound
Black is usually rich. Make sure that side pipe isn't restricted and the carb is not leaking or delivering more fuel. It could be a bad plug or coil wire not burning the fuel completely.. Were compressions equal?

01' Raptor 720, Stage 2, FCR'd
97' 250 Vitos Blaster
06' Rhino 450
94' Banshee T-5's, Vforce, ported, Cool Head, 2-1
06' Wolverine 450 - Stock!
06' LTZ 440
94' Vmax4 750, 96' 600 MountainMax, 07' Nytro(b00sTed)
06' Vmax 1200
diggerzmound is offline  
Sponsored Links
post #4 of 4 Old 01-31-2017, 09:00 PM Thread Starter
TRU211's Avatar
Join Date: Dec 2015
Location: Az
Posts: 46
Im rebuilding it right now so everything still apart. Im jst trying to find out why it happened so i dnt repeat it! I didnt chec the compression b4 i took it apart. My 1st banshee and this is my second time rebuilding it. I had detonation and a bottom rod and bearing blow out so i had to replace that so now im gona start rebuilding it ! I did all the work myself so fingers crossed!!!
TRU211 is offline  

Quick Reply

Register Now

In order to be able to post messages on the Yamaha ATV Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Please enter a password for your user account. Note that passwords are case-sensitive.


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:


Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode

Similar Threads
Thread Thread Starter Forum Replies Last Post
Yamaha raptor 660R blowing black smoke while turning over Talhelm94 Yamaha YFM660R Raptor (2001-2005) 6 09-26-2016 09:04 AM
Piston Slap? Yfzr363 Yamaha YFZ450/450R (2004-Present) 3 08-23-2016 05:39 PM

Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

For the best viewing experience please update your browser to Google Chrome