400 ex piston and ring install - Honda ATV Forum
Repair & Maintenance Having problems? Doing a rebuild? All Repair/Maintenance Discussions here.

 
LinkBack Thread Tools Display Modes
post #1 of 7 (permalink) Old 02-21-2013, 10:08 AM Thread Starter
Member
 
spittinyamahas's Avatar
 
Join Date: Feb 2013
Location: pa
Posts: 32
Liked: 1 times
400 ex piston and ring install

ok so as some of you know i havea a 2001 trx400ex with a namura 440ex big bore kit,i got my complete top and gasket kit and my piston and rings in the mail today,i have a few questions,first of,the gaps between the rings on the piston,i measured them to make sure they werent to close or the ends weren't touching eachother,but the only thing im stumped on is,witch way do the gaps between the rings need to face,ive been told since there is no pin on the piston to just make sure they all point in the oposite direction of eachother,is that true? and i put the new valve seals on it and the top end gasket kit came with o-rings??? i don't remember taking any o rings off of the quad? just the gaskets,are theses extra or did i miss something on the tear down??? im new at this and need all the help i can,this is my first time doing a top end rebuild on a 4-stroke engine
spittinyamahas is offline  
Sponsored Links
Advertisement
 
post #2 of 7 (permalink) Old 02-21-2013, 11:22 AM
Senior Member
 
Tippmann98's Avatar
 
Join Date: Jan 2012
Location: NE Ohio
Posts: 731
Just make sure none of the gaps on the rings are lined up with each other. Set the first ring, turn the next one so the gap is 120 degrees off from the first one and turn the last one 120 degrees from that one.
Tippmann98 is offline  
post #3 of 7 (permalink) Old 02-21-2013, 11:27 AM
Senior Member
 
Josh's Avatar
 
Join Date: Aug 2010
Location: West TN
Posts: 1,754
Well you should have a really big o ring. This one goes around the bottom of the cylinder where it goes into the bottom end of the motor. The four same sized o rings go to the valve adjustment caps on the valve cover. The rings I would put them on at a quarter turn difference for each one that away none matches up at all. small copper rings are for the rocker arms. The other off sized gaskets go to the caps for the motor if I remember correctly. Hope this helps.
Josh is offline  
Sponsored Links
Advertisement
 
post #4 of 7 (permalink) Old 02-21-2013, 11:36 AM
Super Moderator
Supporting Member
 
shadetree's Avatar
 
Join Date: Feb 2010
Location: north little rock, ar.
Posts: 29,842
Liked: 1859 times
Quote:
Originally Posted by spittinyamahas View Post
ok so as some of you know i havea a 2001 trx400ex with a namura 440ex big bore kit,i got my complete top and gasket kit and my piston and rings in the mail today,i have a few questions,first of,the gaps between the rings on the piston,i measured them to make sure they werent to close or the ends weren't touching eachother,but the only thing im stumped on is,witch way do the gaps between the rings need to face,ive been told since there is no pin on the piston to just make sure they all point in the oposite direction of eachother,is that true? and i put the new valve seals on it and the top end gasket kit came with o-rings??? i don't remember taking any o rings off of the quad? just the gaskets,are theses extra or did i miss something on the tear down??? im new at this and need all the help i can,this is my first time doing a top end rebuild on a 4-stroke engine
just stagger the rings...just don't line them up with the wrist pin !...as for those left over o-rings ?..i bet they are the valve guide o-rings ?..only way to put them in..is too press the valve guides out...and istall them. this is all that i can think of as to what you have left over ?..they about the size of a dime ?..if so ?..then yeah..those are valve guide o-rings.

'89 trx350D foreman 4x4...'85 vf700c magna, '03 trx450fm foreman 4x4 , 2015 Yamaha waverunner fx cruiser ho, '05 trx500fm
shadetree is offline  
post #5 of 7 (permalink) Old 07-06-2014, 02:12 PM
Member
 
rtincher22085's Avatar
 
Join Date: Mar 2013
Location: Midcoast maine
Posts: 38
What are the gaps for the top ring and second I know oil rings are .015 and I used the equation bore x .0055 is that for top ring?

440 - 89mm - 11:1 Wiseco
Cometic MLS set/stock studs
45 p 170 m Sigma 6 jetting
3rd clip needle/2 turns out
Stage 2 Hotcam
Powerbomb Header
FMF power core 4 /without silencer
Uni foam/ air box lid removed
Razors/ ITP Rims
Nerf bars
+3 A arms +4 Tusk axle
450R shocks
Lonestar carrier
15/38 gearing

DO YOU EVEN BRO?
rtincher22085 is offline  
post #6 of 7 (permalink) Old 07-06-2014, 03:10 PM
Senior Member
 
Coletrain's Avatar
 
Join Date: Apr 2014
Location: Nebraska
Posts: 767
Liked: 69 times
Your piston should have come with a piece of paper with the ring gaps on it.


Sent from my iPhone using Off-Road Forums

2004 trx450r
Rossier exhaust
Ported head
Early HRC cam
+3 stroke
+2bore
13:1 JE piston
42.5mm FCR
UNI
Coletrain is offline  
post #7 of 7 (permalink) Old 07-06-2014, 03:13 PM
Member
 
rtincher22085's Avatar
 
Join Date: Mar 2013
Location: Midcoast maine
Posts: 38
It didn't odd hmmm. Top ring I used bore x.0045 = .015 and 2 and was the bore x .0055 =.019

440 - 89mm - 11:1 Wiseco
Cometic MLS set/stock studs
45 p 170 m Sigma 6 jetting
3rd clip needle/2 turns out
Stage 2 Hotcam
Powerbomb Header
FMF power core 4 /without silencer
Uni foam/ air box lid removed
Razors/ ITP Rims
Nerf bars
+3 A arms +4 Tusk axle
450R shocks
Lonestar carrier
15/38 gearing

DO YOU EVEN BRO?
rtincher22085 is offline  
Reply

  Lower Navigation
Go Back   Honda ATV Forum > Honda ATV Technical Discussions > Repair & Maintenance

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Honda 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:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


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

Email Address:
OR

Log-in









Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.



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



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