Register Community Calendar Today's Posts Search

Go Back   GZ 250 Forums > GZ250-Specific > General Maintenance

Reply
 
Thread Tools Display Modes
Old 06-26-2010, 10:41 AM   #21
chandlerbingfl
Senior Member
 
Join Date: Apr 2010
Location: Florida
Posts: 142
Re: High idle...

Quote:
Originally Posted by Easy Rider
Quote:
Originally Posted by chandlerbingfl
p.s. One thing I have noticed, when shutting it off I do get one pop of backfire?!?!?!
I think THIS might be important, as well as your statement that the idle "started creeping up".

All that can also be a sign of a vacume leak. Check the boots on both sides of the carb for loose, cracked, etc. Also the vacume line going to the petcock.

I'm kind of surprised that the problem hasn't affected engine performance when riding; if it gets worse, it probably WILL. If it is a vacume leak, it can cause the engine to run hotter than normal due to the leaner mixture.
Bike is in near new condition, only had 1200 miles when I bought it... no signs of damage to any of the hoses as I checked them already.... I posted previously... how does the choke work? Does the black plastic piece just slide in and out to restrict air flow so more fuel gets passed to the cylinder?

chandler



Login or Register to Remove Ads
chandlerbingfl is offline  
Reply With Quote
Old 06-26-2010, 10:43 AM   #22
Easy Rider
Senior Member
 
Join Date: May 2007
Location: Champaign, Illinois
Posts: 4,561
Re: High idle...

Quote:
Originally Posted by alantf
Quote:
Originally Posted by dhgeyer
I say lean is good.
Sorry, can't agree with that. Lean can do all sorts of damage,

my valves need adjusting MUCH less often,
You are taking his comment out of context.

An engine properly designed to run lean IS good.
Or, as it would seem that we have here, and engine that is tuned to run on the lean side of its design window.

Nobody is claiming that running ABNORMALLY lean is good.

Further, I think that your claim about valves is........mmmmm.....not based on actual data.
How is it that you think you have enough information to make that claim ?? :roll:
__________________
Loud pipes risk rights!
Easy Rider is offline  
Reply With Quote
Old 06-26-2010, 10:53 AM   #23
Easy Rider
Senior Member
 
Join Date: May 2007
Location: Champaign, Illinois
Posts: 4,561
Re: High idle...

Quote:
Originally Posted by chandlerbingfl
Bike is in near new condition, only had 1200 miles when I bought it...

how does the choke work? Does the black plastic piece just slide in and out to restrict air flow so more fuel gets passed to the cylinder?
What does the bike being new have to do with anything ?? Clue: nothing.

The choke plunger works by opening up an extra passage for fuel flow. If it really is moving freely over it's whole range (might be hard to tell if it is going all the way back IN though) then it is HIGHLY unlikely that it is causing the problem. Gumout and Seafoam have spray carb cleaners.
You could get some and spray the plunger just in case it is gummed up.

I don't remember looking at it but isn't the OFF position for the plunger when it is IN ??
And you have never said explicitly if you have the choke all the way OFF when this happens......that is, the choke lever pushed all the way FORWARD. It might be possible that the handle bar lever itself is binding.

I still think you need to get OFF this choke thing.......at least long enough to check out some other things.......like the carb boots. On my GZ, they were so loose that I could grab the carb and twist it inside boots.......with very little effort.

You came here asking for advice and, except for the location of the choke mechanism, it doesn't seem like you are listening.
__________________
Loud pipes risk rights!



Login or Register to Remove Ads
Easy Rider is offline  
Reply With Quote
Old 06-26-2010, 10:58 AM   #24
chandlerbingfl
Senior Member
 
Join Date: Apr 2010
Location: Florida
Posts: 142
Re: High idle...

Quote:
Originally Posted by Easy Rider
Quote:
Originally Posted by chandlerbingfl
Bike is in near new condition, only had 1200 miles when I bought it...

how does the choke work? Does the black plastic piece just slide in and out to restrict air flow so more fuel gets passed to the cylinder?
What does the bike being new have to do with anything ?? Clue: nothing.

The choke plunger works by opening up an extra passage for fuel flow. If it really is moving freely over it's whole range (might be hard to tell if it is going all the way back IN though) then it is HIGHLY unlikely that it is causing the problem. Gumout and Seafoam have spray carb cleaners.
You could get some and spray the plunger just in case it is gummed up. I don't remember looking at it but isn't the OFF position for the plunger when it is IN ??

I still think you need to get OFF this choke thing.......at least long enough to check out some other things.......like the carb boots. On my GZ, they were so loose that I could grab the carb and twist it inside boots.......with very little effort.

You came here asking for advice and, except for the location of the choke mechanism, it doesn't seem like you are listening.
Well even though I haven't had a bike in a long time I do know about vacuum lines, the boots, etc and I do NOT see anything wrong with them... Two mornings ago I did use the choke to start the bike in the morning just to get it to warm up a bit faster... that is why I am focusing on the choke. When I let the bike sit yesterday for several hrs it started and idle'd normally until it got to temp. If it was a leak or boot issue I do not think that would have been the case...

I DO appreciate the input and I AM listening... but I have checked out all the things put on the table at this point. If you want to insult me go ahead...

chandler
chandlerbingfl is offline  
Reply With Quote
Old 06-26-2010, 11:33 AM   #25
alantf
Senior Member
 
alantf's Avatar
 
Join Date: Nov 2008
Location: Tenerife (Spain)
Posts: 3,719
Re: High idle...

Quote:
Originally Posted by Easy Rider

Further, I think that your claim about valves is........mmmmm.....not based on actual data.
How is it that you think you have enough information to make that claim ?? :roll:
I seem to remember many, many, years ago, an old mechanic telling me that it was wrong to think that you would gain anything with a weak mixture. This was in the days of leaded fuel, so it may not hold good today. He explained that the weaker mixture would cause more heat, which would cause the valve seats to pit. He also said that the lead was a sort of "lubricant" & helped the valve seats. I know for a fact, though, that at every service the mechanic who checked my valves said that he hadn't had to adjust them. At the 15000km service, he said that he had adjusted them SLIGHTLY. With all the posts about American bikes needing a lot more adusting, I think that the richer (slightly cooler) mixture may have something to do with this. Or, have you any other explanation?
__________________
By birth an Englishman, by the grace of God a Yorkshireman.



Login or Register to Remove Ads
alantf is offline  
Reply With Quote
Old 06-26-2010, 12:06 PM   #26
Easy Rider
Senior Member
 
Join Date: May 2007
Location: Champaign, Illinois
Posts: 4,561
Re: High idle...

Quote:
Originally Posted by chandlerbingfl
If it was a leak or boot issue I do not think that would have been the case...

I DO appreciate the input and I AM listening... but I have checked out all the things put on the table at this point. If you want to insult me go ahead...
No, listen, it is not intended to be an insult. It is insulting when one offers advice based on YEARS of experience and then the ensuing replies makes it LOOK like it is being totally ignored.
Are we on the same page there ??

And here's the problem: The WAY in which you are "checking" things isn't good.......and some assumptions you are making aren't good either. Pointing those things out is not an insult; it is necessary to bring the process to a good end.
Still on the same page......I hope.

As for the vacume leak, looking and even touching maybe is NOT a sufficient test. Pulling on the boots or twisting them might be good enough.....along with checking the clamps for tightness.....but the best method is to spray a small amount of carb cleaner or WD40 or starting fluid (but it can be dangerous) around each of the boots and vacume lines one at a time.......while the problem is evident. If the engine speed or sound changes in any way, there IS a vacume leak. Often they can't be detected with the naked eye.

AND vacume leaks often DO GET WORSE as the engine components heat up.

That's all I've got to offer. Unless new evidence comes to light, I'm done.

P.S. Where did you buy the bike? If it was a dealer, you should be able to make an appointment to have them look at it while you wait; you might want to consider that even if you didn't get it from a dealer.

Like a lot of technical problems, the actual repair is likely to be minor and with their experience they might be able to go right to it and the whole thing might be very inexpensive.......or maybe even free if you bought it there.

Good luck!!
__________________
Loud pipes risk rights!
Easy Rider is offline  
Reply With Quote
Old 06-26-2010, 01:37 PM   #27
Sarris
Senior Member
 
Join Date: May 2007
Location: New Port Richey, Florida USA
Posts: 1,348
Re: High idle...

Hey Chandler, I suggest a couple of tanks with fuel system cleaner (amount per mfgr's recommendation), then take it out and run the crap out of it for 50 or 60 miles a few times. It really sounds like a partially gummed up idle circuit. If it were me, I would do this first.

GeeZers seem to get gummed up carbs fairly often when not used regularly. I don't know what year yours is, but with only 1200 miles it doesn't sound like it's had a lot of use.

My two cents worth.

:2tup:
__________________
Prudent riders live longer than moron riders.
Sarris is offline  
Reply With Quote
Old 06-26-2010, 02:25 PM   #28
Easy Rider
Senior Member
 
Join Date: May 2007
Location: Champaign, Illinois
Posts: 4,561
Re: High idle...

Quote:
Originally Posted by Sarris
Hey Chandler, I suggest a couple of tanks with fuel system cleaner
Blaine beat you to the punch on that one.......and I agree with both of you.

Gummed carbs are very common.
Vacume leaks are fairly common too.
Sticky choke and throttle cables less common.
Actual choke (enricher) trouble IN the carb is pretty rare.....but that still could be the problem.
Hell, it could even be a head gasket that needs to be torqued down but that is rare too.
__________________
Loud pipes risk rights!
Easy Rider is offline  
Reply With Quote
Old 06-26-2010, 04:24 PM   #29
Water Warrior 2
Senior Member
 
Join Date: Dec 2006
Location: Squamish B.C Canada
Posts: 11,409
Re: High idle...

Quote:
Originally Posted by alantf
Quote:
Originally Posted by Easy Rider

Further, I think that your claim about valves is........mmmmm.....not based on actual data.
How is it that you think you have enough information to make that claim ?? :roll:
I seem to remember many, many, years ago, an old mechanic telling me that it was wrong to think that you would gain anything with a weak mixture. This was in the days of leaded fuel, so it may not hold good today. He explained that the weaker mixture would cause more heat, which would cause the valve seats to pit. He also said that the lead was a sort of "lubricant" & helped the valve seats. I know for a fact, though, that at every service the mechanic who checked my valves said that he hadn't had to adjust them. At the 15000km service, he said that he had adjusted them SLIGHTLY. With all the posts about American bikes needing a lot more adusting, I think that the richer (slightly cooler) mixture may have something to do with this. Or, have you any other explanation?
Yes, lead was used as a lubricant among other things. Combined with a slightly richer mixture there would be a cooler running engine in most cases.
Water Warrior 2 is offline  
Reply With Quote
Old 06-26-2010, 05:10 PM   #30
Easy Rider
Senior Member
 
Join Date: May 2007
Location: Champaign, Illinois
Posts: 4,561
Re: High idle...

Quote:
Originally Posted by alantf
Or, have you any other explanation?
Yes. I think you assume way too much.
What makes you think that "american" bikes need the valves adjusted more often than is your experience ??

I don't think there is any evidence to indicate that is the case.

My GZ when checked around 3K miles needed no adjustment; don't know if that was the first check or not. I didn't keep it long enough to need a second check.

Now, are you ready for this.........
That was the FIRST bike in about 35 years that I ever had the valves checked on.
About 10 different bikes over ~35 years and never touched a valve; never.

The first check on my Shadow needed some adjustment on about half the valves. It ran better after. As long as it runs good, I don't intend to check them again until 2X the recommendation ......or more.

I'm not necessarily saying that your assertion is wrong, just that I suspect that it is a guess based on scant little real evidence or data.
__________________
Loud pipes risk rights!
Easy Rider is offline  
Reply With Quote
Reply




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

Forum Jump


All times are GMT -4. The time now is 08:26 PM.


Powered by vBulletin® Version 3.8.4
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.