Rieju & GasGas Legacy Riders Club Forum  

Go Back   Rieju & GasGas Legacy Riders Club Forum > GasGas Enduro Technical Forums > Enduro Engine - 2 stroke

Enduro Engine - 2 stroke Cylinder, Piston, Tranny, Bearings, Clutch, Pipes & Silencers, etc.


Reply
 
Thread Tools Display Modes
  #1  
Old 06-18-2017, 04:35 PM
Davehuge's Avatar
Davehuge Davehuge is offline
Senior Member
 
Join Date: May 2017
Location: English but now based in South of France.
Posts: 470
Default Power valve end play, side to side movement, rattle...

Hi all

I recently bought a well used 2004 EC300. The engine seems to be in good condition. It was running a bit rough but after adjusting the carb it's running sweet now.

My last remaining issue is a terrible rattle, it's very noticeable on overrun, for example rolling down a steep bank with the throttle shut.

I removed the left and right power valve covers and also the exhaust. The power valve seems to be well adjusted, it sits against the closed stop and has no slack in the mechanism.

I stuck my fingers up the exhaust port, I could feel a lot of side to side play/movement of the power valve. When I move it left/right I also hear the horrible rattle that I hear on overrun.

Questions:

1. Is there anyway to remove the sideways movement of the power valve (possibly with shims?) and thus reduce or eliminate the horrible rattle noise that I have?

2. Is it possible to remove the power valve unit without removing the cylinder head/barrel from the engine?

Thanks and best regards, Dave.


Reply With Quote


  #2  
Old 06-18-2017, 06:55 PM
Jacob 'Berg Jacob 'Berg is offline
Senior Member
 
Join Date: Mar 2014
Location: Scottsdale, AZ
Posts: 589
Default

Quote:
Originally Posted by Davehuge View Post
Hi all

I recently bought a well used 2004 EC300. The engine seems to be in good condition. It was running a bit rough but after adjusting the carb it's running sweet now.

My last remaining issue is a terrible rattle, it's very noticeable on overrun, for example rolling down a steep bank with the throttle shut.

I removed the left and right power valve covers and also the exhaust. The power valve seems to be well adjusted, it sits against the closed stop and has no slack in the mechanism.

I stuck my fingers up the exhaust port, I could feel a lot of side to side play/movement of the power valve. When I move it left/right I also hear the horrible rattle that I hear on overrun.

Questions:

1. Is there anyway to remove the sideways movement of the power valve (possibly with shims?) and thus reduce or eliminate the horrible rattle noise that I have?

2. Is it possible to remove the power valve unit without removing the cylinder head/barrel from the engine?

Thanks and best regards, Dave.
Yes, you can remove the power valve without removing the cylinder. You will need to remove both PV side covers and get the piston at BDC. It should come out the exhaust port. I would remove the head so you can push the flap out.
Reply With Quote
  #3  
Old 06-19-2017, 03:34 AM
poelinca's Avatar
poelinca poelinca is offline
Senior Member
 
Join Date: Jul 2015
Location: Bucharest, RO
Posts: 302
Default

Not sure about 2004, but on my 2014 i removed most of the side to side movement by pressing the left hand side bearings in a bit more (just a tad, maybe less than 1mm, if i press them more the PV get's stuck probably on the left exhaust valve).

p.s. Did you check the rocker arm on the right side or the bell crank hitting the case ? It's pretty common for them to bang on the cylinder or case, to check remove the right side PV cover, put the pipe back in, start the bike and rev it a tad, you will see the rocker arm moving and rattling, make sure it's not banging on the cylinder (if it's banging on the case, you should see marks on the case, you have to drain the coolant, the case oil can stay in just lean the bike on the left side when removing the case cover). Here is a video on youtube that helped me out a lot in removing most of my rattles at high rpms https://www.youtube.com/watch?v=dI0fUUHaDjQ
__________________
'14 EC300
Reply With Quote
  #4  
Old 06-19-2017, 08:26 AM
swazi_matt swazi_matt is offline
Senior Member
 
Join Date: May 2010
Location: From Swaziland, Now Hamilton New Zealand the “look but don’t touch” enduro heaven
Posts: 2,334
Default

you sure it is not the exhaust o-rings that are worn?
__________________
2003 txt250 Pro
2013 Ossa 280i
Reply With Quote
  #5  
Old 06-19-2017, 05:48 PM
Jakobi's Avatar
Jakobi Jakobi is offline
Super Moderator
 
Join Date: Oct 2010
Location: Australia
Posts: 7,994
Default

My experience has been that they are just noisy old 2 strokes. The pipes can rattle against the spigot, against the mounts if not aligned correctly. The rads/braces can vibe up against thing. Plastics can clatter. Bash plates will rattle. Everything is always way more evident on decel because:
a) the exhaust isn't making any noise to cover it up, and
b) as the revs fall it always goes through the range where the crank is least balanced. This increases the vibes, felt, heard, etc. Under throttle you tend to have a load on the piston and also move through this area faster.. Find it and hold a steady throttle and it'll buzz away through the bars and pegs more than most would enjoy.

Last edited by Jakobi; 06-20-2017 at 04:35 PM.
Reply With Quote
  #6  
Old 06-20-2017, 04:19 AM
Davehuge's Avatar
Davehuge Davehuge is offline
Senior Member
 
Join Date: May 2017
Location: English but now based in South of France.
Posts: 470
Default

Thanks for the advice and suggestions.

I'm a bit busy at the moment but as soon as I've investigated it more I'll post feedback.

All the best, Dave.
Reply With Quote
  #7  
Old 07-01-2017, 11:59 AM
Davehuge's Avatar
Davehuge Davehuge is offline
Senior Member
 
Join Date: May 2017
Location: English but now based in South of France.
Posts: 470
Thumbs up Fixed!

Finally had time to look at the exhaust power valve today.

I removed the left hand side power valve cover. I pushed the power valve bearings all the way in and then, using my digital caliper, measured the gap to the retaining washer, or rather the face that the retaining washer sits on. It was 1.8mm.

Luckily, I found a suitable washer 1.6mm thick. I placed the washer between the inner bearing and the part that pivots and turns the power valve. Thus leaving 0.2mm clearance to avoid jamming the system.

It worked great, the rattle has gone. Just been for an 60 minute ride and all is fine.

I think this is self explanatory, but if anyone needs to see a photo then just ask.

All the best, Dave.
Reply With Quote
  #8  
Old 10-22-2019, 02:28 AM
Liam88 Liam88 is offline
Member
 
Join Date: Sep 2019
Posts: 2
Default Power Valve photos

Hey Dave,

I think I am experiencing the same issue with my EC300 2014.

Looks like the spacing washer has worked for you!

Do you have any photos to show your success?!?!

Regards
Liam.
Reply With Quote
  #9  
Old 10-22-2019, 02:46 AM
Davehuge's Avatar
Davehuge Davehuge is offline
Senior Member
 
Join Date: May 2017
Location: English but now based in South of France.
Posts: 470
Default

Hi Liam, I'm sorry I don't have any photos. My bike's at my house in France but I'm over in the UK at the moment.

All the best, Dave.
Reply With Quote
  #10  
Old 11-21-2021, 04:07 PM
JAD JAD is offline
Member
 
Join Date: Nov 2021
Location: Warrington, UK
Posts: 83
Default

I appreciate this is an old thread but can I just confirm that the original poster has inserted an extra washer/shim alongside the one shown by the arrow?
(or was his missing and he replaced it?)




power valve.png
__________________



Retired
EC 250 (2007)
UK
Reply With Quote
Reply



Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not 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


Similar Threads
Thread Thread Starter Forum Replies Last Post
Side cover power valve bearings? Terrence R Enduro Engine - 2 stroke 19 04-29-2016 07:26 AM
Power valve rattle on 2012 tonyraft Enduro Engine - 2 stroke 6 09-27-2013 11:52 AM
POwer Valve Rattle PEB Enduro Engine - 2 stroke 3 03-22-2012 10:33 PM
Power valve rattle dickieshep Enduro Engine - 2 stroke 1 07-03-2011 01:33 PM
power valve rattle not chain slap gasgasandrew Enduro Engine - 2 stroke 47 06-11-2009 05:24 PM




All times are GMT -5. The time now is 08:53 AM.


Powered by vBulletin® Version 3.8.6
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Copyright 2009 - GasGasRider.org