Looks good. Are you happy with the new engine?
Thanks I appreciate the kind words. I don't usually share too many details about my projects so it's nice to have a place where I can do that.
I'm very happy with the new engine, it's a nice improvement over the stock 400. Nice little boost in torque and I'm looking forward to seeing what the rest of the powerband is like after it's broken in.
The first ~200 miles were great but now I'm having some sputtering issues. I thought it might have been a fuel issue with the single carb kit & adapter I made to move the carb around the frame (frame is in the way on the early 400s). I cleaned the stock carbs from my second parts bike and installed those with stock 74 airbox (found a cheap parts bike to put my parts bike back together lol..) I was expecting that to improve things but it's still having issues. I'd be happy running stock carburetors at least for a while as long as it stays reliable. Worry about more performance later. I had the single VM34 dialed in perfect on the stock 400 so we'll see what ends up working here. For now I'm going to check everything over starting with the ignition system. Check timing, swap out the coil and if that doesn't improve things pull the carbs and clean them again. They need to be re jetted anyway so they are coming off either way.
I hope it isn't anything internal. It doesn't seem like it. No blow-by or anything like that.
Quick recap of the build:
1974 KZ400 (previously restored, bought it with a blown head gasket)
Engine, wiring, wheels, swingarm from my 79 LTD 400
440 cylinders and +.5mm pistons - 446cc
No cylinder base gasket. Used high torque Permatex instead
Head shaved .5mm, ports cleaned up, thicker valve spring shims
Charlies Place electronic ignition and coil relay. OEM coil for now
Still experimenting with carb setups
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