Full throttle performance


Information and questions on GL1500 Goldwings (1988-2000)
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Elmobile
Posts: 224
Joined: Sat Aug 22, 2015 8:35 pm
Location: Bridgewater, Nova Scotia, Canada
Motorcycle: 1990 GL1500SE

Full throttle performance

Post by Elmobile »



Well, my brake issue is resolved,
My coolant leak is under control,
Now to what I hope will my last problem, at least for the next while...

I have what feels like a lack of power when I open the throttle wide open in 5th gear. I have never ridden a GL1500 before but when I am mid throttle, about 2500 to 3000 rpm in 5th gear, nothing happen when I accelerate. I know that I am pulling a sidecar and I have an Austine tire, so none of them are helping but I am quite sure it is not the way the bike should behave.
From previous reading of this forum, I have replaced the gas filter with a new OEM. The carbs have been replace by a set of 1996 (The bike is 1990 with 170K kms) and they have been rebuilt with a Randakk kit. All the vacuum hoses have been either replaced or are in good shape. Mixture screws are set at 2 turns and the carbs are balanced. Today I went for a ride and left the gas tank cap open. It did feel somewhat better but still not the way it should be. So the gas cap is now soaking in Seafoam.
The petcock was bypassed during this ride to see if the petcock was faulty. Does not seem to affect my problem so I will rebuilt it during my winter maintenance but is not likely the root cause.
My gas consumption is bad, about 10l per 100kms. The spark plugs, all 6 of them, are very black.
I remember reading about the coolant temperature sensor located in the right intake manifold causing this kind of issue. It is use by the CPU in 4th and 5th gear, I believe?

I would appreciate any comments or suggestions...
Cheers.



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Rambozo
Posts: 471
Joined: Sun Apr 01, 2018 8:36 pm
Location: Disneyland
Motorcycle: 1992 GL1500 Aspencade

Re: Full throttle performance

Post by Rambozo »

Fuel consumption is not way out of line considering a side car and short trips. But the black plugs indicate you are running rich. Don't expect it to pull hard in OD, you need to drop down a gear or two for good acceleration.

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Elmobile
Posts: 224
Joined: Sat Aug 22, 2015 8:35 pm
Location: Bridgewater, Nova Scotia, Canada
Motorcycle: 1990 GL1500SE

Re: Full throttle performance

Post by Elmobile »

Agreed, the bike is running rich. Even the muffler tail are getting cover in black soot. That would be my basic question...
I am use to down shift when needed and realize that with the sidecar you need to use your gear box. Here I am talking like no response from the engine, nothing! 1/2 throttle to full in 5th makes no differences... I am not expecting much pick and go but at least some acceleration.

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bigsteveswing
Posts: 143
Joined: Mon Jun 11, 2018 4:40 pm
Location: Erie, PA
Motorcycle: 1992 GL1500I
Motorvation Formula II sidecar

Re: Full throttle performance

Post by bigsteveswing »

I get about the same MPG as you are getting, especially on short runs to work and back, 7 miles one way. Best I have gotten is 26mpg, of course that is pushing the sidecar and hauling a lot of extra weight on the seat... :) I do have some acceleration in top gear if I am on flat ground, though I'm not gonna win any races. Uphill is a totally different story, have to downshift no matter what. I have only put on about 500 miles total though so I am not sure how good a test subject I am.
Big Steve
Keep America Strong: Weld It
8-)

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Rambozo
Posts: 471
Joined: Sun Apr 01, 2018 8:36 pm
Location: Disneyland
Motorcycle: 1992 GL1500 Aspencade

Re: Full throttle performance

Post by Rambozo »

Have you done a compression or cylinder leakage test to see how tight things are?

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DenverWinger
Posts: 1524
Joined: Thu Jun 23, 2011 2:20 pm
Location: Denver, CO
Motorcycle: (s)
1980 GL1100 STD Vetter (2005-)
1993 GL1500 Aspencade (2017-)
1983 Trav-Lite Camper (2010-)
Past rides
1972 CL350 (1980-1988) sold
1978 Suzuki GS550 (1985-2005) sold
1977 GL1000 (2002-2006) sold

Re: Full throttle performance

Post by DenverWinger »

Not sure how pulling a sidecar compares with traveling 2-up and pulling a fully loaded camper trailer at around 550lbs, but even in the rolling hills of NE Kansas at 65 MPH, cruise "on" it would pull nicely up those hills (some of them pretty steep) in 5th gear, the CC getting close to WOT at times but always holding the set speed within a couple MPH!

As stated, won't win any acceleration races in OD but still good torque available in 5th. Rarely find the need to downshift per losing speed unless I'm riding some of the Colorado steep mountain grades...

So it does sound like you are having some issues if there's little-to-no difference between half throttle and WOT. My first thought was maybe some problems in the carb slides, but if they weren't opening completely seems that would cause lean rather than rich condition..... Hm....
♫ 99 Little Bugs in the Code, ♪
♪ 99 Bugs in the Code. ♫ :(
♫ Take one down, Patch it around, ♪
♫ 127 Little Bugs in the Code. ♫ ♪ :shock:

~Mark

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AZgl1800
Posts: 2408
Joined: Thu Oct 30, 2008 2:46 pm
Location: Lake Oologah Indian Territory USA
Motorcycle: '02 GL1800
2009 Piaggio MP3 250cc

Re: Full throttle performance

Post by AZgl1800 »

Loaded like it is, it will probably run faster ( mph ) in 4th gear than it will in 5th gear.

when I first bought my '98Se, in Tampa, FL and riding it home to Arizona.....
I have run at 105 mph in 4th w/o any problems at all, for several miles when I was pushing hard into a heavy head wind. Just one of those times when I wanted to see what it would do.... and the speed limit was 85 and 105 miles from the nearest stop sign.
~John

'02 GL1800
2009 Piaggio MP3 250cc

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hugger-4641
Posts: 282
Joined: Wed May 25, 2011 1:07 pm
Location: McKenzie, TN
Motorcycle: 1994 GL1500 Aspencade, 1982 CM 200 Twinstar, 1984 VT500 Ascot

Re: Full throttle performance

Post by hugger-4641 »

I never had any problems in 4th, but when I started loosing power above 80mph in 5th, it was my fuel pump.

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Elmobile
Posts: 224
Joined: Sat Aug 22, 2015 8:35 pm
Location: Bridgewater, Nova Scotia, Canada
Motorcycle: 1990 GL1500SE

Re: Full throttle performance

Post by Elmobile »

Thank you for all the comments. Sorry for not following up sooner. Right now I am getting my tractor ready for the winter...
Denverwinger, your description on the bike behavior in 5th is what I would expect even with my sidecar... And it is not what's happening.
AZgl1800, your comments gave me reassurance to push harder in 4th gear which I wasn't before.

So I went for a quick ride getting down in 4th when going uphill. It did help as expected so I kept going for a ride on the highway... There I was able to push both 4th and 5th gear. In 4th, you can feel a faint sputtering after 4000 but she is going strong. In 5th, the sputtering is more noticeable. She will go but if going uphill you quickly loose speed. I've added a couple of pictures showing the end of the mufflers getting sooty. That is with only 100 miles... So I believe something is going on...

I was going to leave the fuel pump alone because the behavior in 4th gear was strong but after hugger-4641 comment, I think I will use the 5' of fuel line I just bought to check it out anyway. Easier to get to it rather than the "engine coolant temperature sensor". I have read that it can cause the engine to run rich on all 6 cylinders. I am not sure how this sensor impact the carburation but if the pump is good, it will be my next line of investigation...




Thanks again for all the input. I let you know what I find!

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Corkster52
Posts: 640
Joined: Sun Jun 06, 2010 9:28 am
Location: Naperville, IL
Motorcycle: 1999 GL1500 Aspencade
1988 GL1500 (sold 4/17)

Re: Full throttle performance

Post by Corkster52 »

Might just be my imagination but I really think putting iridium spark plugs in both of my 1500s gave them more "oomph".

Arcweld80
Posts: 20
Joined: Wed Oct 16, 2019 10:25 am
Location: Sweden
Motorcycle: GL 1500 1988

Re: Full throttle performance

Post by Arcweld80 »

I hade similar problem with my bike... i noticed that the carb vent hoses was clogged some how when i blew in them!! Even after the vacum valve to the canister it was a stop!!
It is common sense that when fuel is filling up the float chamber the air must get out!!!

So i removed all of the "california" emision stuff and put a new hose från the "t-pipe" and ran it along the side of the the bike. And did the same thing with the fuelcap! So now they can vent right out in the air! And plugged the vacum hose that went to the valve. Its was like a new bike!! No more hesitation in the midrange or that nasty stumble at take of.

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CrystalPistol
Posts: 1398
Joined: Wed Mar 10, 2010 9:07 pm
Location: Shenandoah Valley of Virginia
Motorcycle: 1997 GL1500SE/'98 Lehman Trike

Re: Full throttle performance

Post by CrystalPistol »

Elmobile wrote:
Sun Oct 13, 2019 7:41 pm
… etc … I have what feels like a lack of power when I open the throttle wide open in 5th gear. I have never ridden a GL1500 before but when I am mid throttle, about 2500 to 3000 rpm in 5th gear, nothing happen when I accelerate. I know that I am pulling a sidecar and I have an Austine tire, so none of them are helping … etc … My gas consumption is bad, about 10l per 100kms. … etc … Cheers.
Last time I went WOT … I was west bound … I pulled the earth 4.7 seconds out of time. It was a mess, people resetting clocks and all? :shock:
I wonder what 10l per 100kms is in MPGs? :?

In all seriousness, pulling a side car at 60 mph in OD, the extra weight, the likely doubled wind resistance, well below torque peak. Not surprised. ;)


Make Courtesy your "Code of the Road" …

… & Have a Safe Trip!
:)

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