Owner of 2 Honda Gyros

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Vodka
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Owner of 2 Honda Gyros

Post by Vodka »

First off, Glad there is a Honda Gyro friendly resource.
I will say I am more into 'Mopeds' and not scooters but could not resist the uniqueness of this little scooter.

I have 2 Gyros that need some general repair/upkeep and parts. Seemingly the part above the seat, and the carburetor cover seem to just disappear over the years, haha. Not a lot of people have those and I need a couple of each.
Anyway here we go.

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The black one is a 1985, the red an 86. I am very new to gyros, not very new to 2-stroke motors ( reed valve, case inducted motors are just fine for me )
I know the black is a "Gyro S", not actually sure if the red one is considered an S ( don't have it in front of me) I recall the title saying "Color: Red, and 1986"

Better pictures to come

I will be asking some questions in this thread. I typically do that when I want to be spoon fed, I am perfectly capable of finding the answer/figuring it out but I have done a lot of trial-and-error ( mainly error) and do not wish to go through the error side.

The driveable one is the black gyro. With the help of an external fuel bottle (as pictured)

So first up with black gyro is a petcock cleaning. It will NOT run gas through the tank.
The fuel bottle works awesome. So clearly between the carburetor fuel inlet, and the tank there is an obstruction (petcock pickup, the selector, or fuel line has an obstruction)
Were in for some new fuel line tomorrow and a flush of the tank. Ill work on that and document that tomorrow.

The Red 86 is Missing a wheel and brake hub, and a carburetor and exhaust, and the mentioned covers.

I was thinking the black gyro will be my stock build, the red will be my mod build.

Anyone delete oil injection? I have done some quick searches but found no one specifically removing it, only that some one recently 'forgot to connect' their oil line and blew their cylinder.
In either case all my other vehicles are premix and I am physically capable of premixing.

The red will get a 18-24mm carb, and a nice pipe if I can figure out what people have done for putting pipes on the gyros, how the clutch setups and clutch springs help.

I think I've already seen big dio intakes on a gyro I think.


Anyway, hopefully I can help some one with my thread, and this is the beginning.
Grab the service manual here " http://projectmopedmanual.info/Manual_HTML/honda.html "
and almost done reading through the 40+ page thread 'Gyro - general thread' " viewtopic.php?f=1&t=17452 "
mousewheels
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Re: Owner of 2 Honda Gyros

Post by mousewheels »

Anyone delete oil injection? I have done some quick searches but found no one specifically removing it, only that some one recently 'forgot to connect' their oil line and blew their cylinder.
In either case all my other vehicles are premix and I am physically capable of premixing.
Please post questions outside of Builds to Technical Help forum.

--
Deletion of oil injection for a Gyro only requires removal of the oil pump, deletion of the oil pump drive shaft and drain/plug of the oil inlet line.

Gyro's oil pump drive is on the non-pumping side of the crankcase, so there is no concern for increasing crank case volume by removing the driveshaft.
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deuce217
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Re: Owner of 2 Honda Gyros

Post by deuce217 »

I do not know much about gyros but I would be very interested in seeing aftermarket pipe work done. Clean looking rides. I have not inspected the oil injector pump on my gyro yet but most of the time you just need to remove the pump and plug its hole with something that can seal that up. Somebody on here used a few coins and some rtv. I machined one form graphite impregnated nylon (nylatron) basically a plastic rod and turned it on my lathe. The main thing is you dont want to lose crankcase pressure so its best to get something in the pump's hole, that takes up as much space as possible.

The pump will have some line that connects either to the intake or carb itself. You must plug that with some form of nipple or you will introduce a very lean condition to your motor. Then it will seize.

You could probably take the pump out and grind the teeth all the way down on a grinder and just put it back in there. But I would preserve the pump myself.
2000 Elite SR50 -THE PURPLE NURPLE
50mm BBK (tai)
26mm OKO (round slide) 135 Main Jet
V-8 pipe
39/18 secondary gears (7.583:1 ratio)
36 grams in Prodigy variator
Malossi Delta Clutch & WIng Bell- Thanks RED EFT
65mph GPS (on the freeway)
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deuce217
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Re: Owner of 2 Honda Gyros

Post by deuce217 »

mousewheels wrote:
Anyone delete oil injection? I have done some quick searches but found no one specifically removing it, only that some one recently 'forgot to connect' their oil line and blew their cylinder.
In either case all my other vehicles are premix and I am physically capable of premixing.
Please post questions outside of Builds to Technical Help forum.

--
Deletion of oil injection for a Gyro only requires removal of the oil pump, deletion of the oil pump drive shaft and drain/plug of the oil inlet line.

Gyro's oil pump drive is on the non-pumping side of the crankcase, so there is no concern for increasing crank case volume by removing the driveshaft.
Well never mind what I said about the crankcase pressure... Mouse wheels squared that away while I was typing.
2000 Elite SR50 -THE PURPLE NURPLE
50mm BBK (tai)
26mm OKO (round slide) 135 Main Jet
V-8 pipe
39/18 secondary gears (7.583:1 ratio)
36 grams in Prodigy variator
Malossi Delta Clutch & WIng Bell- Thanks RED EFT
65mph GPS (on the freeway)
Vodka
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Re: Owner of 2 Honda Gyros

Post by Vodka »

That is a great idea just to grind off the teeth on the gear. I would prefer a blockoff plate for the clean look, but that would be functional. I have made a plate with just 1/8" steel, planed flat on some sandpaper and glass, gasketted, and some of my favorite brand sealer if I feel like it.

I have another bike that the oil reservoir is a functional gas tank.

Funny you should mention the oil pump gearing in the crankcase. I don't know of any bike that has.


Yeah I will definitely hack a pipe on, just need to find the best candidate.
I have access to a welder finally so I love any chance I can get to weld.

To be clear I know what an airleak is too.

Are the crank seals any good on these gyros?

It seems like every other Honda needs crank seals. I know from what I have seen that one of them is bathed in oil - hopefully meaning it lasts longer with the exposure to less air/sun/temps?
Vodka
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Re: Owner of 2 Honda Gyros

Post by Vodka »

Well here is how I got my fuel tank working so I don't have to use a fuel bottle...

Start by removing your seat and plastics
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Dont forget these two after you get the cover off
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Remove your fuel line and vent line
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Then unbolt your tank
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my petcock had caked in gunk.
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I went ahead and replaced the fuel line with Motion pro brand fuel line. The fuel line does not have braiding on it like the stock line but I think it will be just fine.
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photo in progress - match existing lengths

Drained the oil tank too from the previous owners random clear 2-stroke oil.... smelled like gear oil
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Just used some oversized tubing to fit over the oulet of the reservoir
Vodka
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Re: Owner of 2 Honda Gyros

Post by Vodka »

Also had to check the cylinder on my other gyro to see if its going to be a parts gyro or if its worth running.

Its pretty straight forward as well.
Remove the exhaust bracket and cylinder cover
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Image thick skirting, very sturdy
Image super clean bore and piston
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The cylinder looked awesome and there looked like some easy way to free up some power. The side transfers don't even open up all the way. I think you could raise the cylinder with a thicker base gasket and take material off the head to gain back your compression ratio.

and hack out some material in the exhaust being careful not to create any dans
Image exh
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