mitovarna

Here is a video of the bike running, with my audio commentary concerning what is apparently a lean condition evidenced by the backfire you hear.  Like many things, the advice/suggestions to deal with the condition are often contradictory...

According to online forums, the backfire could be caused by a lean condition, or an exhaust leak.  Of course, timing could be the culprit, which is evidenced by the very hot headers even at idle.  However, many mx450 engines do this, so glowing headers do not necessarily mean a lean condition.  There is no exhaust leak in the pipe, but the slip fit by the muffler is somewhat suspect, but that shouldn't cause the backfire alone.  Finally, nonstandard pipe and carb is no help, so the baseline to start is nonexistent.  Since the advent of fuel injection, no one stocks carb parts, so pilot jets will need to be ordered (already on the way...)  The joys of building and fabricating!!!  I'll get it figured.  Over the winter I will likely drop the engine and do a full inspection -- valves, timing, filters, etc.  Will have lots of time to do it!

RIP Marco

mito details

Some pics for your enjoyment.  Waiting on a $9 part to check to see if I've got the cooling system fixed.  Rad came from Germany quicker than a rad cap came from the US.  Typical teutonic efficiency.

new clothes

Had some time with an extended fall to get the new fairings mounted and painted.  Clear coat applied over the top.  Plain numbers for now... or in compliance with AMA rules...?

Also still working on the mitovarna.  Since getting the completed exhaust back from cycleboyz, have gotten it running.  Still facing a typical bugbear -- cooling.  Seems to be a regular problem with most of my projects, save the klx400.  The KTM rad sits too low, and my theory is that despite purging the system of air, I still had a vapour lock/cavitation issue.  I have seen pictures of this exact frame and this exact engine, but the radiator used was a mito rad.  A bit small, but it would be better than what appeared to be no water flow that I was experiencing to date.  So, I will simply copy what apparently works, so a mito rad is on the way.  Cycleworld did an article on a crf450 engined mito, with again some fancy plumbing but the mito rad as a base.  I found a complete cooling system off of ebay Germany, so I will see if this works better.  Hopefully it gets here soon, as I would like to put the mito to bed for the winter knowing that it runs (which it doesn) but that it is adequately cooled (not yet).  I also tore the entire machine apart this past weekend, and rebuilt it wet -- using grease, etc on the bearing surfaces.  Went together nicely, and I think the suspension as is is not a million miles off.  Still need some minor parts -- a shipment of husky-specific stuff is on the way, a jet kit from thumpertalk, and some spacers to fit the r6 front caliper.  Some brake hoses, and I welded up a tubing mount for the rear muffler.  Not seen below due to it being painted.  IF I get the mito rad to work, I will be a bit pissed, as the radiator flares on the sides of the fairing will be made redundant.  Oh well... the bike still looks pretty cool.