Keith's Raptor 80 Project Page

Finishing up after the frame off resto.

First ride for Keith after the resto. Decided the stance was too narrow so ordered new tires with offset wheels.

Added LED lights front and rear. Thanks to Palmer industries, Keith has a matching fuel jug as well. These two photos taken February, 2009.

February 2010. The engine was tired and smoking so we opted to overhaul it for the 2010 season. The cylinder had rust pits and the intake valve was shot.

All the parts cleaned and ready for reassembly.

Transmission gears and crankshaft reinstalled in the case. Sides of crank were tapered to lighten and I was able to remove 183 grams. Lightening the crank and flywheel definitely helped acceleration off idle. The new piston weighed in the same within 1 gram of the old one so engine balance was not an issue.

Old piston right and new piston left. The new one is 3mm (.120) oversize. Old piston is cast aluminum and the new one is forged. Even though the new one is considerably larger diameter, they weigh within one gram of each other.

Lightened the flywheel 50 grams and repainted it.

Discovered that it was possible to add 4th gear to the Raptor by using the shift drum and gear from a late 80's Badger or Champ 100. I found the parts on E-Bay really cheap. Keith's main shaft is on the bottom and you can see his original gears. The far left gear from the top set was added to Keith's setup and the lower of the two shift drums was used. As you can see the channels for the shift forks are machined a little further around to activate 4th gear for a 1 to 1 final drive ratio. 

Gears installed and case halves buttoned up. Got ahead of myself and didn't get any photos of the inside gear arrangement. rh photo shows the piston installed.

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