New Non-KX Project

[umberto]

I still have the 1980 Honda Z 50 that I rode as a kid.  It is not my first bike, but it was one of my favorites.  I often flip dirt bikes on Craigslist for fun and to make a little money to support my habit.  I usually buy bikes that are in rough shape and in bad need of some TLC.  I call them my "Redneck Rescues".  My dad asked me to do a RR on this bike.  Needless to say young Umberto was not as kind to his bikes as present day Umberto is.  The bike was in sad shape, so my son and I blew it apart for easier transport from my parents.



We installed new races, and the 40 individual ball bearings that make up the steering stem.  Also installed the swingarm and shocks:



Next came the motor, airbox, pipe, seat, wheels, new brakes, and number plates:




I bought some cheap reproduction fenders from Flea Bay, but they were only red on the top.  I used them to check all the mounting holes and hardware.  I've got some brand new OEM fenders that are going on when I get closer to done:



Just waiting for one last round of small stuff from BikeBandit.com, and I should be done and riding.  Not sure what Dad has planned, but it's sure been a blast to work on.

[umberto]

Got the last few little things on the bike yesterday.  Now I'm just waiting on the tank to get painted.  In the "whew" moment of the day, the old bike still has fire.  A fresh plug rewarded me with a fat blue spark.  Now I just need to put some gas in the carb and see if she'll live again.

[sandblaster]

I love it 
Thanks for posting..

[umberto]

Quick project update:  So I've been kind of stuck with the Z.  I think the exhaust valve may be sticking open and letting the charge escape.  I know the intake valve is moving and I can feel the intake suction, but so far it hasn't even tried to start.  That makes me think stuck or not seating exhaust valve, or rings.  Dang I hate four strokes. 

I've been down with a bad back, but am on the mend and should be able to tinker with it a bit this weekend.  I'll post a ride video if I can get it up and going this weekend. 

[sandblaster]

Sorry to hear about your back... I've been dealing with a large herniated disc for the last 20+ years so I can feel for ya.
A quick compression test will verify your theory.
But.... you probably knew that 

[umberto]

I actually have a Harbor Freight compression tester.  I take it with me on all my "Redneck Rescue" buys.  It can be really handy for sure!

[umberto]

Good call on the compression test Sandblaster.  It was only holding 30 PSI.  My dad is an old hot rodder, and suggested putting a little oil in the cylinder to lubricated the valves and seats and got it to 60-70 PSI.  I got the gas tank back from my dad today, so I should be able to try starting it with real petrol instead of ether.  I'm hoping 60 is enough to get it running long enough to get the valves warmed up and seating better.  I'll keep you posted.

[umberto]

Got my tank back from the painter.  So shiny...  

[sandblaster]

Looks great....

[umberto]

I got the tank mounted and the OEM fenders installed.  All I have left to do is paint the wheels and install the new tires.



Unfortunately, the bike does not want to start even with real gas.  Does anyone know of a good place to send four stroke motors for repair?  I haven't heard good things about my local Honda dealer.

[81cr450]

I'd really like a 50 for a suitcase bike. Man you could near take it anywhere.

Anyway if I remember right Roost452 used one of these piranha 140 motors in his street legal camp bike. Might be cheaper than building one

http://www.ebay.com/itm/Piranha-140cc-Pit-Bike-Engine-crf50-atc70-crf-50-70-atc-/390887546230?pt=Motorcycles_Parts_Accessories&hash=item5b02b69d76&vxp=mtr

Looks sweet!

[umberto]

I ended up buying a new head on e-Bay.  It's got all new stuff, and should fix the valve issue.  It's a pretty simple swap, with only a couple of sprockets to time. 

[sandblaster]

Yeah good move.
I'd toss a new piston and ring set in it and go ride...

[Brute]

What he said! Once you have the head off the cylinder is easy.
Nice looking project!

[umberto]

I got the piston in today.  Just makes sense to swap it out.  I'll post pics in a bit, I have a hard time posting from my iPad. You guys will get a laugh, the piston and valves are comically small. It's amazing such a small piston can make so much power.