88 gl1500 preformance mod final report


Information and questions on GL1500 Goldwings (1988-2000)
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virgilmobile
Posts: 7644
Joined: Sun Sep 19, 2010 5:39 pm
Location: Denham Springs,La.
Motorcycle: 1988 GL1500 I
Previously owned
78 GL1000
81 GL1100
82 GL1100 I
83 GL1100 I
83 GL1100 standard
84 GL 1200 I

88 gl1500 preformance mod final report

Postby virgilmobile » Sat Jun 16, 2012 2:59 pm



I've been fussing about my 88 compared to my 1200.The 1200 was just snappier and smoother accelerating than the 1500.
These are the things I've done to solve this.
Besides the fluid change,tires,brakes and other maintenance items,I made these changes in the bike.
1.pulled the carbs and re-jetted the idle port.I went from the #55 to a #60.
Obviously this included a good cleaning,sync,and idle screw adjustment with that 2' long screwdriver.
2.rebuilt and modified the accelerator pump.Here's the post about it.viewtopic.php?f=6&t=11658
3. adjust the timing to -4* BTDC from TDC factory specs,by replacing the trigger wheel.
4.unplugged the temperature sensor that feeds the CCM.(not the ECM).It's behind the right pocket,2 wire plug on top that goes to the CCM module.

Every time I did anything to the bike,I would run it out to see if and how it changed.
I do believe,from my test,that any ONE thing that is done will improve the bike to some degree,but it's the combination of all of them that transforms it into a 900lb rocket.

Now it's like my 1200 on NOX. Sheesh. :D :D :D :D
I tried to hold my camera during the last test,but the G force kept moving it to the sky.I'll rig up a mount somehow.Just not on my helmet.I almost need a neck brace when I twist the throttle now.
Just in case you didn't figure it out by now,I really like the bike.
Thanks to this site and it's members for the help,I now run a bike that will stand up and bark when necessary.

Merci Beaucoup
Virgil.



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zamboni920
Posts: 250
Joined: Sun Aug 14, 2011 5:15 am
Location: Stavanger, Norway
Motorcycle: 1996 GL1500 SE with Hannigan 2+2 sidecar

Re: 88 gl1500 preformance mod final report

Postby zamboni920 » Sun Jun 17, 2012 9:39 pm

I like it! Nice job done. Tell me more about the trigger wheel . I still have to do timing belts, and wondered if it was worth doing.

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virgilmobile
Posts: 7644
Joined: Sun Sep 19, 2010 5:39 pm
Location: Denham Springs,La.
Motorcycle: 1988 GL1500 I
Previously owned
78 GL1000
81 GL1100
82 GL1100 I
83 GL1100 I
83 GL1100 standard
84 GL 1200 I

Re: 88 gl1500 preformance mod final report

Postby virgilmobile » Mon Jun 18, 2012 7:54 am

It's ready for the new wheel.
I had to put on a few miles in town to get a feel of how the bike performs before I change it.
That way I can be able to tell if it really makes a difference.Here's a Google pix of the part.

It's due for running by Wednesday.

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zamboni920
Posts: 250
Joined: Sun Aug 14, 2011 5:15 am
Location: Stavanger, Norway
Motorcycle: 1996 GL1500 SE with Hannigan 2+2 sidecar

Re: 88 gl1500 preformance mod final report

Postby zamboni920 » Mon Jun 18, 2012 3:25 pm

Looking forward to know the result of trigger wheel performance.
Just finished my carbs. Bike now runs great....quick response....great torque. Definitely more powerful than my 1200. And that is with final tweaking of idle screws left to do. Have a slight pop in exhaust occassionally. Plus a final carb sync.
Tell me the reasoning behind disconnecting the Temp sensor for Carb Control Module (CCM) . Does it make any difference? Does it affect other systems?

User avatar
virgilmobile
Posts: 7644
Joined: Sun Sep 19, 2010 5:39 pm
Location: Denham Springs,La.
Motorcycle: 1988 GL1500 I
Previously owned
78 GL1000
81 GL1100
82 GL1100 I
83 GL1100 I
83 GL1100 standard
84 GL 1200 I

Re: 88 gl1500 preformance mod final report

Postby virgilmobile » Mon Jun 18, 2012 3:46 pm

As far as I read,It forces the CCM to remain consistant in every rpm range and temperature when it opens and closes the valves.
I noticed that before I unplugged it,when I would shift to 2nd from 3rd, the rpm would increase about 150 rpm.
On my last running,It remained the same idle speed reguardless of what gear I was in.
I'd have to get it underway again and plug it back in to verify it is what changes the rpm.

Did you tend to all the vacuum lines in yours?

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zamboni920
Posts: 250
Joined: Sun Aug 14, 2011 5:15 am
Location: Stavanger, Norway
Motorcycle: 1996 GL1500 SE with Hannigan 2+2 sidecar

Re: 88 gl1500 preformance mod final report

Postby zamboni920 » Mon Jun 18, 2012 5:21 pm

I would think removing any sensor from feeding info to any electronic control module, and getting a positive result, would tell me there is another problem. Personally I would suspect replacing bad vacuum lines associated with the valves have more to do with your consistency in rpm's. It seems almost all components feeding the CCM also depends on vacuum. Just my 2 cents worth.....you might be on to something.
I replaced all vacuum lines on mine, simply because I got a spare set of carbs that included all the vacuum lines, in like new condition. Some , not included, were replaced because they were weak.
Also the sub air filter, wich indeed were dry, and turned to dust in my hands....although it did not seem much of it had been sucked in.....I replaced with a piece from a Briggs&Stratton lawnmower filter. Those are Polyurethane Foam filters, and tend to not dry out, nor be affected by gasoline or fumes, as they are designed to be oilsoaked, like the Honda OEM.
The initial setting on idle mixture screws is set at 1 1/2 out.....but the book says 3 1/8 for the 1988. I tried that , and it ran like poop.
I also think a new diaphragm in the accelerator pump makes a big difference as the old one is very much harder than the new one.
I did do a big no-no per the book, and that was to clean all the little holes in the jets with a small wire(the kind used to clean orifice in torch tips).
I have certainly followed your mods closely, and I like your persistence and courage to experiement. I love to experiment with this stuff....but as hard as it is to access these carbs.....Maybe I'll try something with my spare carbs, then someday try it out in the bike.
Oh....one more thing I did.....against the "rules" but.....For easier work later, I removed the carb heat riser, and instead looped a coolant hose between the two intakes. Have not noticed any negative effect, and might not until weather turns cooler again. Now I can remove the carbs in about half hour....after plastic is removed.

User avatar
virgilmobile
Posts: 7644
Joined: Sun Sep 19, 2010 5:39 pm
Location: Denham Springs,La.
Motorcycle: 1988 GL1500 I
Previously owned
78 GL1000
81 GL1100
82 GL1100 I
83 GL1100 I
83 GL1100 standard
84 GL 1200 I

Re: 88 gl1500 preformance mod final report

Postby virgilmobile » Tue Jun 19, 2012 12:04 pm

The CCM is also fed gear selector inputs.On the 88 it sees a input on 3,4, and 5th.
I noticed a increase in rpm when I move from 3rd to 2nd.It holds the higher rpm in 2nd,neutral and 1st.
This may be effecting the timing rather than the CCM.
I will have to strobe it to be sure.
I did monitor the output of the CCM before I unhooked the sensor,It did operate the valves by the book at 1500,2000,and 3000rpm.I'll retest that again.
Unhooking the temp sensor while ilding in the shop had no affect on the idle,so at the moment i'm in the dark as to why the rpm's don't change between gears.
All the other "things"you mentioned,I also have done.
It's getting better with each thing.
I think all the plumbing is just compensation for the fuel managment system they designed.
Hey,the Valkrie uses 6 carbs and none of this computer stuff.Same engine(kinda).

I'm just trying to 'tweak it' a bit,without going all out.

I had a old 4 cylinder single barrel mustang that in very cool weather would frost the bottom of the carb and intake manifold to the point of killing the engine.The heater hoses were bypassed to the base on it too.




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