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looking for an air leak... at least i think its an air leak.
Posted: Mon Jun 18, 2012 2:03 pm
by Guy Young
Has been awhile since I've been on here (my apologies), but am looking for a little wisdom from the collective.
I am working on a fella's 2003 KLR that has just shy of 30K on it. The bike came in for a big bore kit install, but also came in with a staring/running issue that the customer was fully aware of. When cold, or warm, the bike requires "choke," but just using it doesn't help. You need to "feather" the throttle to find a sweat spot to where it will light off. Once running, it's readily apparent that the bike has an air leak somewhere. Goose the throttle, and it revs up and is slow to return to a normal idle..... or at least as normal that bike has shown thus far.
I pulled the carb apart early on and could find nothing out of the ordinary. The diaphragm looked a little funky (all wrinkled up), so I replaced that later in the troubleshooting process - to no avail. The o-ring under the carb intake runner was replaced, even tho' it looked fine. The runner (insulator) also looked fine with no cracks or anything. Also pulled the cover to the air cutout valve to check its diaphragm and it was fine also. The bike has had a manual petcock installed and the vacuum port on the carb has been blocked off. I have also played all over the intake system (and carb) with a propane torch looking for any change in engine RPM, but that has shown me nothing.
This is such a simple intake system, but it really has me scratching my head where the problem might be. What am I missing???
looking for an air leak... at least i think its an air leak.
Posted: Mon Jun 18, 2012 2:08 pm
by Eddie
"What am I missing???"
Have you checked the valve lash?
eddie
> [Original Message]
> From: Guy Young
> To: DSN_KLR650@yahoogroups.com>
> Date: 6/18/2012 3:03:48 PM
> Subject: [DSN_KLR650] Looking for an air leak... at least I think its an
air leak.
>
> Has been awhile since I've been on here (my apologies), but am looking
for a little wisdom from the collective.
>
> I am working on a fella's 2003 KLR that has just shy of 30K on it. The
bike came in for a big bore kit install, but also came in with a
staring/running issue that the customer was fully aware of. When cold, or
warm, the bike requires "choke," but just using it doesn't help. You need
to "feather" the throttle to find a sweat spot to where it will light off.
Once running, it's readily apparent that the bike has an air leak
somewhere. Goose the throttle, and it revs up and is slow to return to a
normal idle..... or at least as normal that bike has shown thus far.
>
> I pulled the carb apart early on and could find nothing out of the
ordinary. The diaphragm looked a little funky (all wrinkled up), so I
replaced that later in the troubleshooting process - to no avail. The
o-ring under the carb intake runner was replaced, even tho' it looked fine.
The runner (insulator) also looked fine with no cracks or anything. Also
pulled the cover to the air cutout valve to check its diaphragm and it was
fine also. The bike has had a manual petcock installed and the vacuum port
on the carb has been blocked off. I have also played all over the intake
system (and carb) with a propane torch looking for any change in engine
RPM, but that has shown me nothing.
>
> This is such a simple intake system, but it really has me scratching my
head where the problem might be. What am I missing???
>
>
looking for an air leak... at least i think its an air leak.
Posted: Mon Jun 18, 2012 2:15 pm
by Jeff Khoury
And re- re- re- cleaned the pilot jet and passages?
The symptom you describe is that your idle adjustment could be set too high. This usually happens when there is clogging in the pilot system, you compensate for it here and there and never really notice it. The engine "loping" back to idle is almost a dead giveaway that your idle screw is too far open.
Once your throttle is cracked open a certain distance, there will not be enough vacuum to draw through the enrichener circuit, thereby making your "choke" less effective.
-Jeff Khoury
----- Original Message -----
From: "eddie"
To: "KLR650 list" DSN_KLR650@yahoogroups.com>
Sent: Monday, June 18, 2012 12:08:25 PM
Subject: RE: [DSN_KLR650] Looking for an air leak... at least I think its an air leak.
"What am I missing???"
Have you checked the valve lash?
eddie
> [Original Message]
> From: Guy Young < gbyoung2@... >
> To: <
DSN_KLR650@yahoogroups.com >
> Date: 6/18/2012 3:03:48 PM
> Subject: [DSN_KLR650] Looking for an air leak... at least I think its an
air leak.
>
> Has been awhile since I've been on here (my apologies), but am looking
for a little wisdom from the collective.
>
> I am working on a fella's 2003 KLR that has just shy of 30K on it. The
bike came in for a big bore kit install, but also came in with a
staring/running issue that the customer was fully aware of. When cold, or
warm, the bike requires "choke," but just using it doesn't help. You need
to "feather" the throttle to find a sweat spot to where it will light off.
Once running, it's readily apparent that the bike has an air leak
somewhere. Goose the throttle, and it revs up and is slow to return to a
normal idle..... or at least as normal that bike has shown thus far.
>
> I pulled the carb apart early on and could find nothing out of the
ordinary. The diaphragm looked a little funky (all wrinkled up), so I
replaced that later in the troubleshooting process - to no avail. The
o-ring under the carb intake runner was replaced, even tho' it looked fine.
The runner (insulator) also looked fine with no cracks or anything. Also
pulled the cover to the air cutout valve to check its diaphragm and it was
fine also. The bike has had a manual petcock installed and the vacuum port
on the carb has been blocked off. I have also played all over the intake
system (and carb) with a propane torch looking for any change in engine
RPM, but that has shown me nothing.
>
> This is such a simple intake system, but it really has me scratching my
head where the problem might be. What am I missing???
>
>
looking for an air leak... at least i think its an air leak.
Posted: Mon Jun 18, 2012 2:36 pm
by Eddie
Not valves. (air cut off or the others)
New diaphragm (not pinched/wrinkled).
Vacuum line to petcock tied off/eliminated.
Cleaned/recleaned jets.
Hmmmmm. This one *is* weird.
eddie
> [Original Message]
> From: Guy Young
> To:
> Date: 6/18/2012 3:31:47 PM
> Subject: Re: Looking for an air leak... at least I think its an air leak.
>
> Valve lash (clearances) were checked after installing the big bore kit.
One exhaust valve was out, and I re-shimmed to bring it back into spec.
>
>
looking for an air leak... at least i think its an air leak.
Posted: Mon Jun 18, 2012 2:49 pm
by Jeff Khoury
If it is a vacuum leak, the good 'ol "mist-carb-cleaner-around-all-the-boots-and-vacuum lines" trick should find it.
-Jeff Khoury
----- Original Message -----
From: "Jeff Khoury"
To: transalp1@...
Cc: "KLR650 list" DSN_KLR650@yahoogroups.com>
Sent: Monday, June 18, 2012 12:18:36 PM
Subject: Re: [DSN_KLR650] Looking for an air leak... at least I think its an air leak.
And re- re- re- cleaned the pilot jet and passages?
The symptom you describe is that your idle adjustment could be set too high. This usually happens when there is clogging in the pilot system, you compensate for it here and there and never really notice it. The engine "loping" back to idle is almost a dead giveaway that your idle screw is too far open.
Once your throttle is cracked open a certain distance, there will not be enough vacuum to draw through the enrichener circuit, thereby making your "choke" less effective.
-Jeff Khoury
----- Original Message -----
From: "eddie" < transalp1@... >
To: "KLR650 list" <
DSN_KLR650@yahoogroups.com >
Sent: Monday, June 18, 2012 12:08:25 PM
Subject: RE: [DSN_KLR650] Looking for an air leak... at least I think its an air leak.
"What am I missing???"
Have you checked the valve lash?
eddie
> [Original Message]
> From: Guy Young < gbyoung2@... >
> To: <
DSN_KLR650@yahoogroups.com >
> Date: 6/18/2012 3:03:48 PM
> Subject: [DSN_KLR650] Looking for an air leak... at least I think its an
air leak.
>
> Has been awhile since I've been on here (my apologies), but am looking
for a little wisdom from the collective.
>
> I am working on a fella's 2003 KLR that has just shy of 30K on it. The
bike came in for a big bore kit install, but also came in with a
staring/running issue that the customer was fully aware of. When cold, or
warm, the bike requires "choke," but just using it doesn't help. You need
to "feather" the throttle to find a sweat spot to where it will light off.
Once running, it's readily apparent that the bike has an air leak
somewhere. Goose the throttle, and it revs up and is slow to return to a
normal idle..... or at least as normal that bike has shown thus far.
>
> I pulled the carb apart early on and could find nothing out of the
ordinary. The diaphragm looked a little funky (all wrinkled up), so I
replaced that later in the troubleshooting process - to no avail. The
o-ring under the carb intake runner was replaced, even tho' it looked fine.
The runner (insulator) also looked fine with no cracks or anything. Also
pulled the cover to the air cutout valve to check its diaphragm and it was
fine also. The bike has had a manual petcock installed and the vacuum port
on the carb has been blocked off. I have also played all over the intake
system (and carb) with a propane torch looking for any change in engine
RPM, but that has shown me nothing.
>
> This is such a simple intake system, but it really has me scratching my
head where the problem might be. What am I missing???
>
>
looking for an air leak... at least i think its an air leak.
Posted: Mon Jun 18, 2012 2:53 pm
by Fred Hink
Is the choke working properly? Not sticking, spring is full length and not binding, the seal on your plunger in good shape?
I had a choke not shutting off on a KLR once that was caused by water leaking past the seal to the plunger and had rusted the return spring in two.
Fred
http://www.arrowheadmotorsports.com
From: eddie
Sent: Monday, June 18, 2012 1:36 PM
To: KLR650 list
Subject: [DSN_KLR650] Re: Looking for an air leak... at least I think its an air leak.
Not valves. (air cut off or the others)
New diaphragm (not pinched/wrinkled).
Vacuum line to petcock tied off/eliminated.
Cleaned/recleaned jets.
Hmmmmm. This one *is* weird.
eddie
> [Original Message]
> From: Guy Young
> To:
> Date: 6/18/2012 3:31:47 PM
> Subject: Re: Looking for an air leak... at least I think its an air leak.
>
> Valve lash (clearances) were checked after installing the big bore kit.
One exhaust valve was out, and I re-shimmed to bring it back into spec.
>
>
[Non-text portions of this message have been removed]
looking for an air leak... at least i think its an air leak.
Posted: Mon Jun 18, 2012 3:24 pm
by Jeff Saline
On Mon, 18 Jun 2012 19:03:46 -0000 "Guy Young"
writes:
> Has been awhile since I've been on here (my apologies), but am
> looking for a little wisdom from the collective.
>
> I am working on a fella's 2003 KLR that has just shy of 30K on it.
> The bike came in for a big bore kit install, but also came in with a
> staring/running issue that the customer was fully aware of. When
> cold, or warm, the bike requires "choke," but just using it doesn't
> help. You need to "feather" the throttle to find a sweat spot to
> where it will light off. Once running, it's readily apparent that
> the bike has an air leak somewhere. Goose the throttle, and it revs
> up and is slow to return to a normal idle..... or at least as normal
> that bike has shown thus far.
>
> I pulled the carb apart early on and could find nothing out of the
> ordinary. The diaphragm looked a little funky (all wrinkled up), so
> I replaced that later in the troubleshooting process - to no avail.
> The o-ring under the carb intake runner was replaced, even tho' it
> looked fine. The runner (insulator) also looked fine with no cracks
> or anything. Also pulled the cover to the air cutout valve to check
> its diaphragm and it was fine also. The bike has had a manual
> petcock installed and the vacuum port on the carb has been blocked
> off. I have also played all over the intake system (and carb) with a
> propane torch looking for any change in engine RPM, but that has
> shown me nothing.
>
> This is such a simple intake system, but it really has me scratching
> my head where the problem might be. What am I missing???
<><><><><>
<><><><><>
Guy,
Since the good stuff has already been suggested I'm gonna go with check
the float level. It should be within +/- 1mm of the bowl/carb body
junction. You can put a clear hose on the bowl drain and run it up,
alongside the carb body and then open the drain. That will show you the
level of the fuel in the bowl.
Best,
Jeff Saline
ABC # 4412 South Dakota Airmarshal
Airheads Beemer Club
www.airheads.org
The Beautiful Black Hills of South Dakota
75 R90/6, 03 KLR650
.
.
____________________________________________________________
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looking for an air leak... at least i think its an air leak.
Posted: Mon Jun 18, 2012 4:04 pm
by Guy B. Young II
Hi Jeff.
Yes, I checked that when I went through the carb the first time. Just
checked it again and is spot on.
Guy
On 6/18/2012 4:22 PM, Jeff Saline wrote:
>
> Guy,
>
> Since the good stuff has already been suggested I'm gonna go with check
> the float level. It should be within +/- 1mm of the bowl/carb body
> junction. You can put a clear hose on the bowl drain and run it up,
> alongside the carb body and then open the drain. That will show you the
> level of the fuel in the bowl.
>
> Best,
>
> Jeff Saline
> ABC # 4412 South Dakota Airmarshal
> Airheads Beemer Club
www.airheads.org
> The Beautiful Black Hills of South Dakota
> 75 R90/6, 03 KLR650
>
> .
> .
> ____________________________________________________________
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>
--
GB Young Services, LLC
Posted from the garage...........
Garage Project:
http://gbyoung2.smugmug.com/Family/Garage-Project/11686385_MTJSCh
looking for "classic" klr in durham nc or vicinity
Posted: Mon Jun 18, 2012 8:40 pm
by John Biccum
I'm looking to buy a "classic" KLR in the Durham NC area. If anyone has any
leads, please contact me off list.
In a tangentially-related matter, I'm also looking for a place to store a
bike inside Washington, DC's beltway, hopefully close to a Metro stop.
Again, if anyone has any leads please contact me off list. Reciprocal bike
swap privileges for a bike inside the Beltway would also work: I'd use your
DC bike on occasion , you can use my Seattle bike in return.
[Non-text portions of this message have been removed]