Motodog - Tracked thing

[java230]

Figured I would start a build thread, if you want to see the past discussion its here:http://www.diygokarts.com/vb/showthread.php?t=27041

This is the idea of what I am going for:

I have a gx390 for power.

Track, skid and drivers are being donated from this:

Tear down!

The very front edge of the track is at the vertical piece in front of the jackshaft. I dont know that its ideal, but it has gears, and a brake built in already! The track is still below the bottom of the lip that the jackshaft is on, but not a ton. I do think it would be better to have the weight further back.


More pics:

Im thinking of cutting the front of the snowmobile off right at that vertical edge in front of the jackshaft. Just need to finish pulling the parts I can try to sell.


Front edge of track is about at this line. Gearing suggestions? Thinking of 8:1

Anyway, more pics from last night. 17 million rivets drilled out later, belly pan and foot rests are off.

Pile o parts. Need to sell....

Couldn't resist putting the engine on there.

Here is how far the chaincase sticks out. its 7" from the side of the track tunnel. I may keep it, still not sure, I just hate to throw away a perfectly good jackshaft brake and reduction assembly!

Front of the track is at the black vertical line, proposed cut line is the orange, I think I need to keep a bit of the structure there if I keep the JS and chaincase.

Im thinking maybe a really long chain to keep the engine weight at the back?

Also need to figure out the clutch. The JS is 1" as is the engine output, comet 40's are 1" and 3/4", do they come 1"and 1"?

 

[KartFab]

might need to get it machined down, or use a different jack shaft there are 5/8, 3/4" and 7/8" bore driven units

http://www.mfgsupply.com/gomini/gom...iniclutchtorq40/gominiclutchtorq40driven.html

BMI has had this thing on sale for about a year since its an odd size that doesnt sell so you could get that for a little cheaper

http://www.bmikarts.com/40-Series-Torque-Converter-Driven-78-Bore-_p_1036.html

(and i could sell you just a genuine comet drive unit and a used belt for $70 shipped) My driven units are only 5/8" which may not be sufficient for your needs.

 

[java230]

Hmmm ok good to know, sounds like my jack shaft wont work well then. Unless I go with the honda reduction unit, then I can just use a sprocket and chain.

The front was liberated last night!

Approach angle, not too bad, but Im worried about all the weight being over the angled section of the front of the track. Unless I run a long chain back to the motor and mount it more towards the middle.

The cut off piece had a perfect little piece for a filler panel too!