I have unstuck a few Goldwings with frozen motors.
Each one of the frozen Goldwing motor bikes that i have freed up are still running, and running great.
If you think the engine is frozen, do NOT try to start it with the starter, as you may do damage to the starter not turning and putting a big load on the starter or on the frozen engine, you could break something, rings, mainly, as the three bikes i have unfrozen have been do to rusted rings in the bottom of a cylinder or two, not sure if it is a combination of corn fuel/moisture and sitting, i think you are better off trying to get the engine freed up first.
Id put it on the center stand,
1. Make sure the rear brake is not also seized/frozen and clamping the rear disc/wheel from turning, Put into neutral and try turning the rear wheel.
2. Remove all the plugs, and drop the exhaust headers away from the heads, i shoot in some DIY Pentrating Oil, this works as good or better than any deep penetrent oil, ATF & diesel fuel mixture 50/50 this is what I use to un-freeze frozen motors that have sat for Years.
a. I put the ATF and diesel fuel mixture in the spark plug holes try to fill up the spark plug holes get as much as you can in there, and let it sit for a couple days, put a Clean catch bucket under both heads as a couple valves may be open and the liquid may run through, but save the mixture that runs through and reuse it, (If the penetrant gets dirty from chunks in the Penetrent filter through a coffee filter in a funnel, to remove the bigger pieces) pour it through the open valved cylinders every day a few times a day to wet them.
3. After a couple of days with the DIY penetrating mixture in the cylinders, Put trans into 5th gear, then try and turn the rear wheel, if you cant budge the engine, dont worry, or if you can only turn the engine over a 1/4" fairly easy that is fine, if it wont easily go any more, put the penetrent back in the spark plugs holes and wait another couple of days, patience here will pay off, then try to move the rear wheel again, keep doing this until it moves as well as bikes engine does.
If you are able to get the engine unfrozen, I would do a Engine Oil Change/ Flush, before I ran it to much, to get the old crud out, that is a 1/5 part engine oil to ATF in the engine, this will not make your trans slip, Also, since it have not been run in a while, put the Flush Mixture in at least a week before starting the engine as the Clutch plates could be dry due to OLD Bad engine oil Not wetting the clutch properly.
The flush mixture, is to remove solids as well as a lot of build up from sitting for some time, take it easy on the engine while the flush is in the engine, as you are trying to run the engine clean.
Using this method has never failed me, and i have Not had any broken rings, or other engine parts and the frozen engines have ran Great, and have good compression after I got them started with a DIY engine flush, ran for about 300-500 miles then do another engine oil and Filter change, to remove the engine flush, now it is ready to be ridden how ever you want, full throttle if you want.
I had a couple of really badly Frozen motors, and a couple that weren't to bad just mildly frozen.
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