Hobbit Athena Engine Modifications

Hello all.

My case modifications are in progress.

Might need a few tips / tricks if anyone has some thoughts.

I already welded around my base to where I should be comfortable.

I didn't like the jb-weld method for a long term / permanent solution.

Should I be looking to fill behind the flywheel so I can really hog this thing out or is that more trouble than it is worth?

As for getting it back flat its going to take a lot of file strokes and sandpaper work is it not ?

Planning on running a base gasket + spacer + base gasket, felpro karropak.

unmodded Athena stock size

Graham cut hobbit head

70cc head gasket probably modded slightly

'race/stuffed' crank

TJT

CDI ignition with retarding box

Leo Vince pipe

vm18 or vm20 with home-made or mlm intake depending on what I find around for piping.

Thanks.

Re: Hobbit Athena Engine Modifications

Didn't really get a close up.

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Re: Hobbit Athena Engine Modifications

as far as tips for welding.

bumped to like 50% cleaning action than normal.

I prepped the piece by preheating and brushing.

It sucks to weld because of the contamination and porosity but once you get a good fill base its not half bad. 3/32 I think, green.

Bursts seemed to help. Kind of drop a dot of fill and smooth it out then repeat.

The final product will have some holes though.

Re: Hobbit Athena Engine Modifications

Flatten with either a well setup mill or my technique is usually a file with part masking taped over.

You can remove high spots with a dremel, then run the masking tape covered part of the file on the unmodded edge. Keep scraping down at the welded edge with the uncovered file edge until it matches the original. Then a few passes with a fine file across the whole base to clean up. Sharpie the base before this to be sure there's no low spots

Re: Hobbit Athena Engine Modifications

> JBOT Admin Wrote:

> -------------------------------------------------------

> Flatten with either a well setup mill or my technique is usually a file

> with part masking taped over.

>

> You can remove high spots with a dremel, then run the masking tape

> covered part of the file on the unmodded edge. Keep scraping down at the

> welded edge with the uncovered file edge until it matches the original.

> Then a few passes with a fine file across the whole base to clean up.

> Sharpie the base before this to be sure there's no low spots

That’s a cool technique. May try this when I build a large port Puch kit

Re: Hobbit Athena Engine Modifications

Overpriced Parts /

> JBOT Admin Wrote:

> -------------------------------------------------------

> Flatten with either a well setup mill or my technique is usually a file

> with part masking taped over.

>

> You can remove high spots with a dremel, then run the masking tape

> covered part of the file on the unmodded edge. Keep scraping down at the

> welded edge with the uncovered file edge until it matches the original.

> Then a few passes with a fine file across the whole base to clean up.

> Sharpie the base before this to be sure there's no low spots

You just figured this out now !

Re: Hobbit Athena Engine Modifications

TOTALLY glad I asked!

I always wanted to do an athena kit properly but always wanted it to do myself.

Im going to hit up the store for some files tomorrow, thanks fam.

more pix to follow.

Re: Hobbit Athena Engine Modifications

Is that an exclamation or a question roffsroyce

Re: Hobbit Athena Engine Modifications

No even I know what I typed. I was way too excited!

Re: Hobbit Athena Engine Modifications

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Re: Hobbit Athena Engine Modifications

Hobbit holder

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Re: Hobbit Athena Engine Modifications

do you have the alignment dowels in there? doesn't look flush to me but might be optical illusion.

Re: Hobbit Athena Engine Modifications

I in fact do have the dowels but thank you for helping me double check.

Found a guy in town with a surface grinder and he said he could probably take this as is and flatten it but yall seem to be able to do this at home so I gotta try it also. Maybe v2 will be done right.

Gonna cut some templates and figure out if I built up enough weld to match the Athena.

What ped/scooter is the Athena originally made for?

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Re: Hobbit Athena Engine Modifications

It’s made for the Camino, which is a euro hobbit. I’m not sure on any differences in the case, but I know the variator and driven pulley are different. It is possible there are other nuances.

Re: Hobbit Athena Engine Modifications

Ana L. of the Aurora Roras /

Spray glue a few different grits of paper on glass or stone. Deck it flat looking for low spots that could leak. 320, 400, 600..

Re: Hobbit Athena Engine Modifications

I need to weld more. I cut out an outline of the kit and i need to go further on the deep side of the case. Monday, more progress.

Re: Hobbit Athena Engine Modifications

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The Cheetachrome Athena case

Re: Hobbit Athena Engine Modifications

We're welded up fam.

Left side Dr kit 60mph, right side???? To be continued.

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Re: Hobbit Athena Engine Modifications

Ana L. of the Aurora Roras /

Open up the kit transfers then match to the case, sharpen the transfer stuffers cut a hole in the top of the piston, get a larger mass head shorten and sharpen side skirts. Careful going too deep on the ignition side it gets thin, or add some material to the top. I’d get some alumaweld and melt it in there.

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Go ahead’n Hogg it out!

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Re: Hobbit Athena Engine Modifications

Ana L. of the Aurora Roras /

Looks like u have plenty of space now with the extra welding. Cutting a large transfer definitely goes out of the sealing surface. A lot of guys build it up with alumaweld. Easy to apply once u get the hang of it. I piled it up 1/2” thick a couple times. Fuck, now I wanna get some more.

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Lay it on a solid flat surface with sandpaper glued or taped down, drag it back and forth to deck it the last little bit.

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