Knocj under load


Information and questions on GL1100 Goldwings (1980-1983)
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swmoman47
Posts: 3
Joined: Fri Oct 09, 2015 8:40 am
Location: carl junction, mo usa
Motorcycle: 1982 gl1100a

Knocj under load

Post by swmoman47 » Thu Mar 22, 2018 5:13 pm



I can start my 82 1100A and it fires right up and purrs when idling with NO knocking even when you Rev it up. But when you take off riding, you can hear a knocking sound when I have it under load. Any ideas?



DaveO430
Posts: 467
Joined: Fri Jan 02, 2015 7:28 pm
Location: Amity. Ar
Motorcycle: 2010 GL1800
2004 Suzuki DR200

Re: Knocj under load

Post by DaveO430 » Thu Mar 22, 2018 5:38 pm

One thing that sounds like a knock but it's in the air box is if you don't have the valve clearance set exactly right. I had an 83 that would spark knock on 87 octane too.

swmoman47
Posts: 3
Joined: Fri Oct 09, 2015 8:40 am
Location: carl junction, mo usa
Motorcycle: 1982 gl1100a

Re: Knock under load

Post by swmoman47 » Thu Mar 22, 2018 6:20 pm

I was thinking just that. I had a blown head gasket and later found I had a cracked head and had to replace it. I was thinking valve clearance. Thanks

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WingAdmin
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Motorcycle: 2000 GL1500 SE
1982 GL1100A Aspencade (sold)
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Re: Knocj under load

Post by WingAdmin » Thu Mar 22, 2018 11:32 pm

You most likely need to sync the carbs. The knocking you're hearing is the primary chain rattling under load because of uneven power pulses from the cylinders. The lower the engine RPM and higher the load, the worse it is.

Also check your cylinder compression - if you have one or two cylinders with much lower compression than the others, it can cause this problem.

Earl43P
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Re: Knocj under load

Post by Earl43P » Fri Mar 23, 2018 10:45 am

The day I sold my 82 (I rode it to deliver it to the new owner after his test ride) it knocked pulling out like I had never heard it. It had also been sitting unridden for a few months. By disengaging the clutch, I quickly realized that a brake was dragging (found a hot rear rotor). I went straight back home and cracked the rear bleeder to relieve the pressure and rode it the 12 miles to his house using only the front brakes (and disclosed the issue).

I miss that bike.
When all else fails, RTFM!

99 Valkyrie Interstate
82 GL1100 Sold 3/3/17
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swmoman47
Posts: 3
Joined: Fri Oct 09, 2015 8:40 am
Location: carl junction, mo usa
Motorcycle: 1982 gl1100a

Re: Knocj under load

Post by swmoman47 » Sat Mar 24, 2018 5:54 pm

Okay with the bike on the center stand and it running I disengaged the clutch, put it in gear and let the clutch out. After doing so my knocking noise is coming from the final gear area. Any ideas what this could be now? The motor is quiet as a church mouse. I even adjusted valves and resynced the carbs which were perfect. My valves were good but the noise is now coming from the rear end and it goes away when you depress the clutch handle.

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ekvh
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Location: Grand Forks, ND
Motorcycle: 1977 gl1000

Re: Knocj under load

Post by ekvh » Sun Mar 25, 2018 9:47 am

Peel the rubber boot back at the rear of the motor and swingarm to check the ujoint. Look for metal shavings, then insert a bar into the joint with the bike in gear and apply a slight twist to the joint. There should be no play/slop. After that address the final drive.



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