Blue Pipes

[Beemer]

Hey all, from Vernon B.C.

I have become the proud owner of a 79' GS 1000L
Picked 'er up cheap and it needs some tender lovin' care.

A couple of bugs to work out. Running kind of rough. 4500 RPM is all she wrote.
I figure the pipes are an indicator of some sort.

Any ideas of what would turn the pipes blue on 2 and 4?

Hopefully, Autosol will take the blue off once the problem gets solved.

I'll be pick?en brains and hopefully soon, enjoying the ride. Haven't rode bike since 81'. Here we go again! \\/

Excellent forums!

 

[earlfor]

The first thing I would do is take the carb rack off, dis-assemble the carbs, soak the carb bodies, blow out the passages, and replace all the "O" rings in the carbs.
If the carbs have any blockages, you will never get it tuned properly.

Earl

 

[ihalterman]

2 and 4 may be running way to rich. The excess fuel continues to burn in the exhaust system. This creates a lot of heat. In a dark garage you can sometimes see them start to glow.

Are you using the Enriching system (choke) to get it to stay running?
Is there too much oil on the Air filter? (Causes too much air restriction like a choke)
Exhaust valves may be sticking open a bit.

Lots of things will cause a rich mixture. and lots of things can cause
excess heat.

Hope this helps.
BJ

 

[wrench]

The first thing I would do is take the carb rack off, dis-assemble the carbs, soak the carb bodies, blow out the passages, and replace all the "O" rings in the carbs.
If the carbs have any blockages, you will never get it tuned properly.

Earl

And if you still have problems, PM..Keith Krause :wink:

 

[earlfor]

You're just still mad because in Canada you have to purchase 6 pairs of different sunglasses to have color TV.

Earl

And if you still have problems, PM..Keith Krause :wink:

 

[Beemer]

Lots of fast replies. Thanks!

I get HDTV using 12 pairs of different sunglasses. I hate 6 pair analog TV.

The first thing I would do is take the carb rack off, dis-assemble the carbs, soak the carb bodies, blow out the passages, and replace all the "O" rings in the carbs.
If the carbs have any blockages, you will never get it tuned properly.

Carb's! Arrg..... I was hoping on doing that in a few weeks after riding a bit....lol

The Air Filter is looking pretty new and white.
I used the choke the other night. Pulling it up ? an inch got rid of the intermittent backfiring on the highway and in town.

It was backfiring when I let go of the throttle to change gears. Resetting the timing with old points helped. I now have new points but have to set them up properly as of yet.

I was hoping for electrical re & re. Nothing to do with the stator maybe? This was suggested at a parts counter but it had to do with one bank going down.

I just received the "Haynes GS1000 Fours 77' to 79'" manual in the mail today. For the life of me I can't find the firing order in the manual. What is the firing order out of interest?

 

[earlfor]

Just keep it simple. The left coil fires cylinders 1,4 simultaneously from the left pointset. The right coil and right pointset fires 2,3. The cylinders fire in pairs.

Earl

I just received the "Haynes GS1000 Fours 77' to 79'" manual in the mail today. For the life of me I can't find the firing order in the manual. What is the firing order out of interest?

 

[wrench]

You're just still mad because in Canada you have to purchase 6 pairs of different sunglasses to have color TV.

Earl

LOL, and the 14k modems suck as well :-D ;-)

 

[cberkeley]

Just keep it simple. The left coil fires cylinders 1,4 simultaneously from the left pointset. The right coil and right pointset fires 2,3. The cylinders fire in pairs.

Earl

It is a wasted-spark system is it not? Meaning that athough two plugs fire simultaneously, when for instance cyl1 is on the power stroke (plug fired) cyl4 is exhausting (plug also fired)? and therefore cyl2 will be intaking while cyl3 is compressing?
Therefore it's all phased at 90-degree angles around the crank?
Do I have it right?:?

 

[feelergaugephil]

Autosol doesn't clean off the blue!
I bought a brand new 4-1 Harris, within 2 mins of running the downpipes went blue.
To this day, I just live with it!

 

[Jethro]

It is a wasted-spark system is it not? Meaning that athough two plugs fire simultaneously, when for instance cyl1 is on the power stroke (plug fired) cyl4 is exhausting (plug also fired)? and therefore cyl2 will be intaking while cyl3 is compressing?
Therefore it's all phased at 90-degree angles around the crank?
Do I have it right?:?

Nope. 1 and 4 fire at the same time, and have the same stroke, as do 2 and 3. When 1 and 4 are compressing, 2 and 3 are exhausting. It's phased at 180 degree angles around the crank.

 

[cberkeley]

OK! ........Now I got it!
Thanks, Cletus

 

[Guy]

2 and 4 may be running way to rich. The excess fuel continues to burn in the exhaust system. This creates a lot of heat. In a dark garage you can sometimes see them start to glow.

What is this? Witchcraft??????

The blue headers are indeed an indication that your motor's overheating. This is most commonly caused by either over advanced ignition timing, or by a LEAN mixture. It's unlikely to be ignition timing as the other cylinders would be effected. Is your compression good? If that proves ok strip and clean your carbs, check all your main jets are correct, replace the intake boot o rings and sync them.

 

[Beemer]

Thanks Guy.

Looks like I'll be working on the carb's this weekend.

Thanks all. I'll be back!

 

[KEITH KRAUSE]

Your pic shows cylinders 2 and 4 are very lean. Could be many things.
With the bike sitting so long, it's the standard carb rebuild thing.
Order VM o-ring kit from Robert Barr first. While waiting, carefully remove all bowls, floats, jets, and o-rings and clean with carb cleaner and compressed air. VERIFY the pilot and main jet sizes. Keep a record of how many turns out each pilot fuel screw (underneath) was from LIGHTLY SEATED. Probably about 1 turn out?? The side air screws will be adjusted later for highest rpm, just be careful of stripping the heads while removing as they can be tight. Keep float needle valves and their seat as a unit. Unless you see a good reason for taking them apart, the slide assemblies should be OK if they operate smoothly. However, one of the possibilities of your lean pipes COULD be because someone messed up and adjusted the jet needle e-clips wrong at 2 and 4? So it might be wise to check their needle position before putting the carbs back on. Any disturbance to the slides/needles will require you to bench synch the carbs, which should be done anyway. Don't separate the carbs from each other because the fuel connectors are famous for leaking upon re-assembly (unless you had leaks already.) Adjust floats to .94" if needed. I suggest new bowl gaskets too.
I also suggest replacing the manifold o-rings and replacing the manifold bolts with Allens. Apply a coat of hi-temp bearing grease to the o-rings and torque them to 6 ft/lb. Be sure to check the manifolds too. The manifolds are about $25/30 each but intake leaks will drive you crazy and may also be the reason for the blue pipes. But the o-rings are more common to fail than the manifolds.
Lot of things to do, I know. But it's best to do the whole job as described or you can end up taking the carbs off several times, etc and wasting more time/money by trying to do a minimal job.

 

[Beemer]

Thanks for the reply KEITH.

I timed and set the points and got the revs up. Bike sounded like NEW. It test drove perfectly for about 5 minutes and went back to it's loss of power and stuttering a bit at lower RPM's. It was a slight improvement over what I had.

Yesterday I discovered problems with the pet cock.
http://www.thegsresources.com/_forum/showthread.php?t=93006

I'll be working on the carbs next weekend. I'm hoping the pet cock is somehow starving the carbs. Still working on this hypothesis. Ordering the cock assembly this week.