1978 Honda Hobbit, Part 4 - Kit & Engine Assembly
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 Published On Jan 23, 2015

Installing new Crank, Bearings & Seals in the Cases that were split and cleaned in Part 3.

Crank -

https://www.treatland.tv/honda-hobbit...

Used the Service Manual and information from www.mopedarmy.com

http://www.mopedarmy.com/wiki/Honda_P...

Heated the bearings and one case half (Variator side) in a toaster oven for about 15 minutes and then slid the bearings onto the crank and then the crank into the case half.

The dowel pins that align the cases don't go as far into the Variator case side, so more sticks out so its easier to align (The pins will hit the other case before the bearing).

I could have heated up the other side and just popped it on, but I have the tool -

http://www.amazon.com/gp/product/B003...

so I just used that.

You probably noticed that the crank comes with NTN but in the video I heated them up a bit too much, causing them to change color and likely ruined the heat treating and softened them (annealed) so I replaced with some Nachi 6004 bearings.

http://www.amazon.com/gp/product/B004...

I didn't push the stator side seal in enough at first, it needs to clear the protrusion on the stator.

Switched the case bolts for allen screws as they are easier to torque accurately (and remove later). They are the blue oxide from McMaster Carr - As a thankyou for reading the description I have about 5 sets (five M6x45mm and One M6x85) that I'll mail to anyone who asks (I had to buy in bulk).

The crank is aftermarket, but based on the PA50 II, I have a PA50 I so there are some differences. I just had to slightly machine a 10-16X32 Oil-Bronze Bushing.

http://www.amazon.com/gp/product/B00C...

It should have fit and just needed cutting to length, but the diameter was a little over so I turned it down in my lathe - Sandpaper to take a little off the outside diameter and a hacksaw to trim it to length would work.

I'm using a DR Kit from Treatland -

https://www.treatland.tv/honda-hobbit...

Checked the ring gap and it was fine (0.007" Gauge only just fit) based on the guidelines here -

http://www.mopedarmy.com/wiki/Ring_gap

for a 46mm Piston.

Used a Proxxon IBS/E Rotary Tool -

http://www.amazon.com/gp/product/B001...

to chamfer the corners on all the ports with a diamond coated bit (I don't show it, but I did go back and take the edge off the port on the skirt too).

Cleaned in Purple Power, rinsed in hot water (not shown) and then blown dry.

The Cylinder and head is then installed per the Service Manual.

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