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Cleaning carbs and installing new jets. Are these the right parts?

2K views 30 replies 5 participants last post by  CXPHREAK 
#1 · (Edited)
Hi friends. I'm working on my 83 GL650. I recently pulled off the airbox etc. and installed a few pods, intending to rejet soon. Lately, it's been harder and harder to start, and often runs on one cylinder for 2 or 3 minutes while it warms. Plugs are getting dirty pretty quick.

I'm sure it could be a bunch of things, but I figured I'd follow my plan to clean the carbs, and install new jets.

I bought a set for my altitude, and pulled off the carb. I've removed two, and they're not looking like the new ones. See below.

Metal


Do I have the wrong parts?

Either way...that carb is way dirty.

Below is a photo of the carb, for fun.
Auto part Engine Automotive engine part Carburetor Fuel line


Thanks for any advise. It's been fun so far trying to learn about new stuff.
 
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#2 ·
The bag on the left appears to hold screw in idle jets but looking at the size of them next to the large emulsion tube from your carbs they look too big.

The 2 bags of jets look about right but the picture doesn't show much detail. See if one will fit into the emulsion tube {on left of your photo} in place of the jet installed there now. The larger jet number goes into this tube and the smaller will go straight into the alloy carb body.

What number are those jets?
 
#3 ·
Thanks CXPHREAK. Heh..I didn't realize things fit inside other things here, I guess. I'll work on getting the jet out of the emulsion tube. It's being stubborn.

The numbers on the bags from L-R are: 48 K21 / 2 135 k / 2 130 k

I'll pull the others out, counting the turns, and compare them as well.
 
#5 ·
Thanks again. I didn't understand those numbers quite until I see what you're saying, against the parts. I have them all out now, and they're looking more right (fitment-wise), except for the longer one.

I'll look into getting some 90's, but I'll try to get this back together as a trial in the meantime.

Floor
 
#7 ·
Ok! Progress. I've cleaned everything out, installed the new jets, and put things back together. Installed some new plugs, and started her up. Runs great. Much much better than before. (I'll still get that 90 jet and replace that 130 with it.)

Tried it down the street and it went great for half a mile. Then I started losing power...sputtering a bit, and a healthy amount of blue smoke coming from the left pipe.

I was seeing this smoke before I replace the jets, too...but only for a few days. It's a relatively new development.

I assume I'm burning some oil somewhere. I'll start reading about this symptom and see what I can learn.
 
#9 ·
650s can and do develop slack oil rings while the compression rings remain fine.

Could be gummy rings if the bike has been off the road for an extended period.

Blue smoke could be a rich mixture from the 130 low jet. The bike probably grooves on this when cold but it becomes progressively over rich as the motor warms up.
 
#10 · (Edited)
You will not get happy with this:---->>

Auto part Engine Automotive engine part Carburetor Fuel line


Check the "faces" of the spark plugs.
Brown, black, white, wet, oily, dry ?

How to:
Run the engine warm.

Revs around 6-6.5 k

Kill switch to OFF and at the same time pull the clutch and hold it until you stop the bike.

Unscrew the plugs (attention: VERY hot) and check their faces.

After the check don't screw in -the still warm spark plugs- with force into the bore !!!

In the older days with no bioethanol in the fuel this table was good to determine the carb by the face of the sparky pluggies ;)

Purple Brown Chocolate Headgear Dessert
.
 
#11 ·
You will not get happy with this:---->>

View attachment 93178
Ok, that was a confusing thing as I was putting it together last night. That screw you're pointing to is a pilot screw, if I'm reading correctly. That particular one has that little handle on it whereas the other side doesn't. The handle one came out in 17.5 turns. The other one came out in 13 turns. I put them back in using the same turn counts. What do you mean that I won't get happy with it? It's borked?
 
#13 ·
In fulfilling its epa type function it will restrict your available adjustment when making adjustments on your bike.
I didn't know this.
The handle one came out in 17.5 turns. The other one came out in 13 turns. I put them back in using the same turn counts.
@themdg:
The usual mix screw should be turned in -but not so very hard !!- so that you see the very small tip from inside of the carb/venturi.
Then turn back for two and a half turns.
That's the basic setting.

(Don't forget the sprin, o-ring and little washer for the mix screw.)
 
#19 ·
I warmed it up tonight, and had much less smoke. It's still dying around 2.5k rpms. I think I'd better straighten out the carbs before I try to solve other stuff.

I have the size 90 jets coming in the mail, and I'll get those pilot screws adjusted when I have it out. Then I'll try again and report back.
 
#20 ·
Ok, I have the 90s in, with the 135s. I turned the pilot screws until I could juuust feel the pin coming through, then I backed them both off 2.5 turns.

Starting it up, it runs much richer, and not smooth. Doesn't idle. Clearly black smoke is coming from the left pipe. No smoke coming from the right. Test ride feels like it's chuggy, instead of smooth.

Here is a video of the sounds: https://youtu.be/Qd0xbzwcupQ

Also, my left pipe doesn't have the little 1/2 inch pipe coming out like the right does. I assume it's damaged. See photo.

I'll read up these symptoms more. Any ideas would be appreciated.
 

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#21 ·
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#24 · (Edited)
So .... a photo of the inside of your pods?
Thank you. I tend to jump to other's educated conclusions without applying them to my case correctly. I'll slow down.

Attached are a few photos. The ring that holds my pods does have a lip that hangs into the airway about 1/4 inch. The photos looking into the carb are with the ring seated as it is with the pod attached. While it is over/above the environment ports, it's not covering then directly.

While looking, I noticed the red oil from my pod on the carb. First, I'm making up the idea of spraying a bit of that K&N oil on there, figuring that the similar filters in my cars call for it. Second, seeing the oil in there made me think I sprayed way, way too much after I cleaned them tonight. Do you guys add any oil?

By doing that, I'm guessing that I'm not only preventing nearly all the air from getting in, causing the chug, but also introducing the oil that's producing the black smoke. If that's right, it also explains why the bike ran before with these pods (with much less oil), even though it seems I could get some with a clearer throat.

I've cleaned the pods again, and they're dying.
 

Attachments

#25 ·
I think the pod will need modding. It looks like the usual elcheapo pod that tends to cause problems.

Also, they're likely a paper element. If so, it won't appreciate being oiled.

You can mod the pod, but will need a good contact adhesive to reassemble them as they will fall apart when the necessary material is removed.
 
#29 ·
Wow! I ran it without the pods, and it idles perfect and runs perfect. Took it around the block and go it up to 50 on a larger road. No power loss, no problems. I put the cheap pods back on (dry), and did the same. Idles great, and runs great until about 3k RPM, then starts choking and losing power immediately. I guess the air is not getting in smooth because of the restricted pods. That's just amazing what a difference that little lip is making!

Any particular brand that has the clear throat? I'm assuming a K&N filter should. I'll go see what I find locally, then look online.
 
#30 · (Edited)
Another quick followup with no questions. Still researching the right pods. Something clearer, and maybe a bit larger/oblong.

I did modify them to remove the rubber that was in the way so I could continue testing the carbs, etc.

There is still a small metal lip that blocks the path a bit, about 1/2 as much as the rubber did. The bike doesn't lose power at 3k RPM, but I can feel the hesitation on the high end. Assuming because of that lip, and perhaps the smaller size of the pods. Ok for a temporary solution, IMO. I'll keep at it.

Edit: Wow...just scrolled up on my laptop to see how huge those images are. That's what I get for "attaching" while using the site on my phone. Sorry about that.
 
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