Contact Overland Solutions for all your custom modifications and setup for overland travel.               Discover the extraordinary with Compass Expeditions.

Go Back   The HUBB > Technical, Bike forums > Yamaha Tech

Yamaha Tech Originally the Yamaha XT600 Tech Forum, due to demand it now includes all Yamaha's technical / mechanical / repair / preparation questions.
With more than 58 destinations worldwide, Edelweiss Bike Travel is Number 1 in guided motorcycle tours!
Reply
 
LinkBack Thread Tools Display Modes
  #1  
Old 11 Jul 2009
Tenere99's Avatar
Registered Users
Veteran HUBBer
 
Join Date: Jan 2008
Posts: 122
over revving at idle

Hi my xt600z tenere is revving up to 3000 with the throttle closed. I am in hot dry conditions (Kyrgistan 35c). Any ideas guys??
Reply With Quote
  #2  
Old 11 Jul 2009
Registered Users
HUBB regular
 
Join Date: Jun 2008
Location: Pietermaritzburg
Posts: 63
Air leak on manifold? Partially blocked pilot jet?
Reply With Quote
  #3  
Old 11 Jul 2009
bacardi23's Avatar
Registered Users
Veteran HUBBer
 
Join Date: Sep 2007
Location: XXX<-Portugal->Azores->Santa Maria (island)
Posts: 1,347
did you forget and left thechoke plunger pulled out?? it doesn't go back in after the bike has started!

Vando
Reply With Quote
  #4  
Old 13 Jul 2009
Registered Users
New on the HUBB
 
Join Date: Jun 2009
Location: malaysia
Posts: 13
Just had the same problem, traced it to one of the screws on the secondry carb buterfly valve coming loose and allowing air to be drawn in at idle.

my screw had disapeared completely, or at least i hoped so, but the bike came to an untimley stop about 2 weeks ago about 300k after fixing the problem. Jury is still out on why, but i should know by the end of the week.

But definatly sounds like your drawing air from somewhere.

I checked everything, eventualy went back to basics, removed the carbs and blew through them, thats when i noticed it was the secondry not the primary.

Good luck

Paul
Reply With Quote
  #5  
Old 13 Jul 2009
Tenere99's Avatar
Registered Users
Veteran HUBBer
 
Join Date: Jan 2008
Posts: 122
many thanks.

thanks guys, the problem has now stopped. A guy at the same hostel as I in Bishkek had exactly the same problem with his BMW80GS! Strange, maybe the altitude had something to do with it (800m) or maybe I'm going mad. (highly likely).
Reply With Quote
  #6  
Old 15 Jul 2009
Registered Users
Veteran HUBBer
 
Join Date: Apr 2003
Location: Manchester UK
Posts: 235
Quote:
Originally Posted by Tenere99 View Post
maybe I'm going mad.
Not at all. The stoichiometric ratio for gasoline can vary according to temperature, pressure, load etc. Most modern vehicles have some form of closed loop oxygen sensor. My guess is you were running lean compounded by a botique fuel blend. For gasoline fuel, the stoichiometric air/fuel mixture is approximately 14.7 times the mass of air to fuel. Any mixture less than 14.7 to 1 is considered to be a rich mixture, any more than 14.7 to 1 is a lean mixture - given perfect (ideal) "test" fuel (gasoline consisting of solely n-heptane and iso-octane). In reality, most fuels consist of a combination of heptane, octane, a handful of other alkanes, plus additives including detergents, and possibly oxygenators such as MTBE (methyl tert-butyl ether) or ethanol/methanol. These compounds all alter the stoichiometric ratio, with most of the additives pushing the ratio downward (oxygenators bring extra oxygen to the combustion event in liquid form that is released at time of combustions; for MTBE-laden fuel, a stoichiometric ratio can be as low as 14.1:1). Vehicles using an oxygen sensor(s) or other feedback-loop to control fuel to air ratios (usually by controlling fuel volume) will usually compensate automatically for this change in the fuel's stoichiometric rate by measuring the exhaust gas composition, while vehicles without such controls (such as most motorcycles until recently , and cars predating the mid-1980s) may have difficulties running certain boutique blends of fuels (esp. winter fuels used in some areas) and may need to be rejetted (or otherwise have the fueling ratios altered) to compensate for special boutique fuel mixes. Vehicles using oxygen sensors enable the air-fuel ratio to be monitored by means of an air fuel ratio meter.




I need



Reply With Quote
  #7  
Old 15 Jul 2009
BlackDogZulu's Avatar
Registered Users
Veteran HUBBer
 
Join Date: Oct 2008
Location: West Wales, UK
Posts: 513
I was just going to say something like that.

__________________
1994 XT600E in weird green and lilac, 2002 Triumph Sprint ST 955i in fast red, Blog: http://goingfastgettingnowhere.blogspot.com/
Reply With Quote
Reply


Currently Active Users Viewing This Thread: 1 (0 Registered Users and/or Members and 1 guests)
 
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
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
1vj carb idle settings/adjustment odannyboy Yamaha Tech 6 14 Apr 2009 20:36
Irregular idle vainoman Yamaha Tech 5 26 May 2007 00:27
3AJ Oil Pump Idle Gear - Help jrm Yamaha Tech 1 13 Jun 2006 10:34
XL600LM(pd)-unregular idle speed Bossit Honda Tech 2 6 Sep 2002 22:01
Stalls when you put it in gear at idle 1990XT Yamaha Tech 1 25 Nov 2001 18:05


All times are GMT +1. The time now is 22:32.