Can I tow my GL 1200 in neutral?

[kw6jim]

Hi Guys,
I had a trailer hitch tow dolly built for my GL 1200. The idea is that it will hold the front tire secure and let the rear tire roll on the pavement. My desire is to be able to tow the bike with my car or RV. We're still in the fine-tuning phase of the dolly.

My question - am I taking a chance of damaging the tranny by letting the rear wheel roll in neutral for long distances? I am looking for answers based on both EXPERIENCE and THEORY.

Thank you!

Jim

[DaveO430]

Some of the gears in the trans are in the oil sump and are turning whenever the wheel is turning so I would think it would be fine.

[AZgl1800]

just remember to never, ever, attempt to back up.

with the RV, the turning radius won't be "too bad", but with a car, you can turn the radius "too tight" and it will force the bike to try and lean over in the turn.

Be cautious of trying to make sharp turns, and make sure you have the triple tree snugged down....
I don't recommend putting straps on the handlebars of a Goldwing, too many controls there to mess up.

I have towed a 1972 Yamaha DT-250 many thousands of miles that way, behind both a Renault R16 and also a '74 Suburban.

on that bike, I dropped the chain off the rear wheel.

Please come back and report on how well this works out for you.

We have had a lot of folks ask about doing it, and I have always "warned against it".
My worry was the transmission getting enough oil on the gears.... only half of it is going to be turning.

[DaveO430]

My worry was the transmission getting enough oil on the gears.... only half of it is going to be turning.

Actually all the gears are turning, they are always in mesh with each other, just not locked to the shaft when in neutral.

[DenverWinger]

With the engine not running the oil pump no pressure from the oil pump to the shaft bearings. There's some shafts that will still be spinning. And some spinning gears on a stationary shaft. And if I'm not mistaken, the transmission shafts are above the oil level in the sump. So no splash lube either. Without the oil pump, I'd still be wary....

You might get away with it if you overfilled the crankcase by an extra gallon of oil, then drain it back down before you drive it.

[DaveO430]

With the engine not running the oil pump no pressure from the oil pump to the shaft bearings. There's some shafts that will still be spinning. And some spinning gears on a stationary shaft. And if I'm not mistaken, the transmission shafts are above the oil level in the sump. So no splash lube either. Without the oil pump, I'd still be wary....

You might get away with it if you overfilled the crankcase by an extra gallon of oil, then drain it back down before you drive it.

The transmission is all splash lubed, no oil pumped to it. The pump supplies oil to the engine.

[Ohara]

Could you mount the rear wheel in the tow dolly and pull the bike backwards? No wear on the transmission and improved radius..

[brianinpa]

With the engine not running the oil pump no pressure from the oil pump to the shaft bearings. There's some shafts that will still be spinning. And some spinning gears on a stationary shaft. And if I'm not mistaken, the transmission shafts are above the oil level in the sump. So no splash lube either. Without the oil pump, I'd still be wary....

You might get away with it if you overfilled the crankcase by an extra gallon of oil, then drain it back down before you drive it.

The transmission is all splash lubed, no oil pumped to it. The pump supplies oil to the engine.

Which is probably why they have that caution in the owners manual about towing the bike for long distance while the engine is off.

[WingAdmin]

This question has been asked and talked about here before.

The answer is: do not tow a Goldwing with the rear wheel on the ground. The output portion of the transmission is lubricated by oil from the oil pump, which movies oil through the middle of the shafts, to provide an oil bearing for the gears on the shaft. When towing the Goldwing, the rear wheel will turn the output portion of the transmission (even when the bike is in neutral), but there will be zero lubrication occurring, because the engine-driven oil pump will not be pumping any oil.

This is a really good way to destroy the transmission on your Goldwing.

I might consider it if it was really necessary in an emergency, but I would leave the engine of the Goldwing running, and would limit the speed at which I towed it.

The only way you could do this and guarantee no damage would be to first remove the driveshaft from the swingarm, so that the transmission would not be rotated by the rear wheel turning.

[DaveO430]

The output portion of the transmission is lubricated by oil from the oil pump, which movies oil through the middle of the shafts, to provide an oil bearing for the gears on the shaft.

That you will have to show me.

[WingAdmin]

The output portion of the transmission is lubricated by oil from the oil pump, which movies oil through the middle of the shafts, to provide an oil bearing for the gears on the shaft.

That you will have to show me.

The front of the countershaft is held in place by part number 23151-431-020, the counter shaft bearing holder. The front countershaft bearing fits into it. If you look at the front of it, you will see the oil journal, from where the oil goes into the countershaft:

Here's the other side of the bearing cap, with the bearing installed, and the oil injection shaft visible, which injects the oil into the countershaft:

The countershaft mounts into the bearing holder, as shown:

Similarly, the mainshaft (which includes he output shaft, turned by the wheels) itself is fed oil by the oil passage, part number 23141-MG9-000:

It feeds oil into the mainshaft, which allows oil to move out of the shaft through holes, to lubricate the bearings - one of those holes is visible here:

When the engine is running, it sends oil into those shafts, out through the holes, and into the bearings - and when I say bearings, I'm talking about smooth bearings, not ball bearings. They are brass sleeves and bushings, and the only thing that prevents metal from sliding on metal is a thin layer of oil between them - and it depends on the oil pressure from the engine-driven oil pump to get the oil there and create and maintain that layer of oil.

You're free to do as you wish with your own motorcycle, of course. But my advice would be that if you wish to prevent destructive wear to your transmission, don't tow it with the rear wheel on the ground unless the driveshaft has been removed.

[eklimek]

Bravo.

[eklimek]

(Thank you for correcting the gif in my previous post. )

It seems motorcycle transmissions benefit from lubrication as indicated by the following flow diagrams.

http://www.dansmc.com/4_stroke_oilflow.htm

[DaveO430]

I guess you deleted my post showing you were wrong.

[WingAdmin]

I guess you deleted my post showing you were wrong.

?? I didn't see or delete any post.

eklimek, that page shows a good diagram showing the oil moving into the center of both transmission shafts:

Four cylinder GL oil flow

[DaveO430]

I guess you deleted my post showing you were wrong.

?? I didn't see or delete any post.

eklimek, that page shows a good diagram showing the oil moving into the center of both transmission shafts:

Oil Flow.GIF

Yes it does, and it also doesn't show that it is from the oil pump, because it is not. You can see from the diagram that it flows from that shelf just by gravity.
I have pictures from inside the case but again the forum keeps telling me they are too large.
Don't know what happened to my post if you didn't delete it.

[AZgl1800]

I guess you deleted my post showing you were wrong.

Dave,
I read your post, but it sure is missing now.

[DaveO430]

I guess you deleted my post showing you were wrong.

Dave,
I read your post, but it sure is missing now.

And I have a witness.

[eklimek]

Honda appears to have a patent for this lubrication system.

https://patents.google.com/patent/US7363904

See figure 1

It may not be common in other makes.

[DaveO430]

Honda appears to have a patent for this lubrication system.

https://patents.google.com/patent/US7363904

See figure 1

It may not be common in other makes.

If Honda is spelled Y A M A H A

[eklimek]

Thanks for pointing that out.

[WingAdmin]

Yes it does, and it also doesn't show that it is from the oil pump, because it is not. You can see from the diagram that it flows from that shelf just by gravity.
I have pictures from inside the case but again the forum keeps telling me they are too large.
Don't know what happened to my post if you didn't delete it.

And how does the oil get up on that shelf, from the oil sump? Oh, that's right, it's PUMPED there, by the OIL PUMP. No engine running means no oil pump pumping oil, no oil to the shafts, and no oil on the bearings.

[DaveO430]

Yes it does, and it also doesn't show that it is from the oil pump, because it is not. You can see from the diagram that it flows from that shelf just by gravity.
I have pictures from inside the case but again the forum keeps telling me they are too large.
Don't know what happened to my post if you didn't delete it.

And how does the oil get up on that shelf, from the oil sump? Oh, that's right, it's PUMPED there, by the OIL PUMP. No engine running means no oil pump pumping oil, no oil to the shafts, and no oil on the bearings.

So your previous statement "The output portion of the transmission is lubricated by oil from the oil pump, which movies oil through the middle of the shafts" wasn't exactly correct? Maybe indirectly but still there are gears low enough in the sump to pick up oil and sling it all over the place. Those gears idling on the shaft with no load are not going to need much lubrication. I have worked on a lot more Honda car trannys than motorcycle and they also have something similar to the shaft end caps in the goldwing, and there is no oil pump in a Honda car manual transmission.

[ekvh]

Wading in to the fray, how would oil get up to the bearing at the output shaft in the rear case? I replaced mine once but don’t remember. Is it sealed on both sides?

[Viking]

Yes it does, and it also doesn't show that it is from the oil pump, because it is not. You can see from the diagram that it flows from that shelf just by gravity.
I have pictures from inside the case but again the forum keeps telling me they are too large.
Don't know what happened to my post if you didn't delete it.

And how does the oil get up on that shelf, from the oil sump? Oh, that's right, it's PUMPED there, by the OIL PUMP. No engine running means no oil pump pumping oil, no oil to the shafts, and no oil on the bearings.

So your previous statement "The output portion of the transmission is lubricated by oil from the oil pump, which movies oil through the middle of the shafts" wasn't exactly correct? Maybe indirectly but still there are gears low enough in the sump to pick up oil and sling it all over the place. Those gears idling on the shaft with no load are not going to need much lubrication. I have worked on a lot more Honda car trannys than motorcycle and they also have something similar to the shaft end caps in the goldwing, and there is no oil pump in a Honda car manual transmission.

I dunno which of you fellas is correct here, but if'n it was me, and I was asking this question, then the controversy alone would keep me from towing a bike with the rear wheel on the ground. This would be called erring on the side of caution. If there was a chance in hades that I could chew up my transmission or any part thereof, I would not be doing it.