GStwin.com GS500 Message Forum

Main Area => General GS500 Discussion => Topic started by: humangod on April 14, 2014, 09:49:38 AM

Title: Symptoms of valve clearance out of spec?
Post by: humangod on April 14, 2014, 09:49:38 AM
What are some symptoms our motorcycles will experience if the valve clearance is out of spec?

My bike is idling at 4500 RPM if I pull in my clutch lever while the engine is at 2000 RPM or higher. If I pull in the clutch lever while my engine is at 1500 RPM, it idles around 1200 RPM.
Title: Re: Symptoms of valve clearance out of spec?
Post by: humangod on April 16, 2014, 08:49:58 PM
Really? No one is going to help me?
Title: Re: Symptoms of valve clearance out of spec?
Post by: Janx101 on April 16, 2014, 10:21:55 PM
sometimes it takes a few days for the people with the know how to catch up or notice.... you arent being ignored... just not noticed.. yet!

in the meantime do a forum search for valve clearance type stuff, if there is an active thread then make a comment in that and how you are wondering a similar thing...  :thumb:

im not a valve knowing person though.... so i wont offer you any info on this.... however .. it may let people notice more ... they seem to weigh in after i chatter away a bit  ;) .... like "oh my gods what is he getting wrong now!?"  :icon_mrgreen:

anyway ... plenty of threads on valve clearance , info on the gs500 wiki .... videos on YT from members too i think?

its all good! .. participate a little and your name should get into peoples heads as 'i remember that name' ..  :thumb:
Title: Re: Symptoms of valve clearance out of spec?
Post by: piresito on April 17, 2014, 01:49:55 AM
I don't think valve clearances out of spec would cause that...I think your problem are carbs/vacuum leak related.

Valve clearances would make the bike hard to start cold, bad fuel consumtption, etc...
Title: Re: Symptoms of valve clearance out of spec?
Post by: prmas on April 17, 2014, 02:56:51 AM
As Janxy said, you are not being ignored. If I had any practical ideas on your problem I would offer them but your description of the symptoms has me stumped. :dunno_black:
As Piresito suggested, the first place to look is vacuum leaks and possible carby imbalance. If the balance is not correct the idle will wander and be erratic.

Macka
Title: Re: Symptoms of valve clearance out of spec?
Post by: gsJack on April 17, 2014, 05:32:54 AM
You are describing hanging idle a not uncommon problem with the GS500 usually caused by a too lean fuel mixture.  Your solution could probably be cleaning the carbs although it could be caused by a vacuum leak as suggested above rather than dirty carbs.  However it's not impossible that out of spec valves could be involved.  Your 1st post indicates you bought a 2001 GS around June of 2009 with low mileage on it, no indication of current mileage.

You should have checked your valve clearances since you got the bike and if you haven't done so recently it should be done now.  A tight valve will be indicated by a rough idle at cold startup and a loose valve by hearing it ticking.  Although a tight valve will generally get loose as the bike warms up running them with too little clearance will shorten the life of exhaust valves in the long run.
Title: Re: Symptoms of valve clearance out of spec?
Post by: cWj on April 17, 2014, 04:52:16 PM
Mark another vote for remote the tank and:

Check for air leaks, particularly the intake manifold/ boots,
Check/clean/ adjust carbs
Check/adjust valves

This seems to be a pretty common refrain for new users picking up old GSes. This is the process my bike went through to get right when I got it with 17.8K miles. After that it ran like a perfectly normal, cold-blooded, stock GS.

Title: Re: Symptoms of valve clearance out of spec?
Post by: JAS6377 on April 17, 2014, 06:12:06 PM
Quote from: cWj on April 17, 2014, 04:52:16 PM

Check for air leaks, particularly the intake manifold/ boots,
Check/clean/ adjust carbs
Check/adjust valves


+1

It should also be noted that a carb sync should be done after the valve check if you changed the clearances at all.
Title: Re: Symptoms of valve clearance out of spec?
Post by: Jimbob on April 17, 2014, 06:46:07 PM
Do you always need to sync carbs if you adjust valves?
Title: Re: Symptoms of valve clearance out of spec?
Post by: robfriedenberger on April 17, 2014, 06:49:13 PM
Check your valves maybe ? When was the last valve check should
Should keep notes of your valve specs and service dates and miles. If you haven't checked your valves in the last 4k miles than it's past due.


Sent from my iPhone using Tapatalk
Title: Re: Symptoms of valve clearance out of spec?
Post by: JAS6377 on April 17, 2014, 07:07:33 PM
Quote from: Jimbob on April 17, 2014, 06:46:07 PM
Do you always need to sync carbs if you adjust valves?

I guess you don't really have to. I synced my carbs early last season, then did a valve check. When I went to sync them again, they were spot on. But it is suggested. If you change the valve clearances by different intervals on each side, it could throw the sync out of whack.
Title: Re: Symptoms of valve clearance out of spec?
Post by: Jimbob on April 17, 2014, 07:16:34 PM
Good to know. Cheers