Old Chappy, Wot?

I've known this little scooter for about 15 years now.  My wife's best friend and her husband found it at a swap meet (Carlisle, maybe?).  He fixed it up and lent it to us for a while.  We had some good fun with it.  We gave it back, they rode it some, then were looking to sell it.  Well, my wife found out and put the kibosh on that!  It's lived in our garage, tucked out of the way collecting dust for the last five years or so. 

Yesterday, I thought I'd blow the dust off of it and see if I could get it running.  Compression and spark are good, so I suspected the carb was gunked up.  Put a little fuel/oil in it, but couldn't get it running unless I dribbled a bit into the spark plug hole.  Put it up and came in to eat dinner.

Today, I figure I'll clean it up a bit.  Ordered a carb kit from ebay.  Just for kicks (no pun intended) I tried to start it.  Fired up on the first kick.  Runs good at idle, but leans out as you open the throttle and it wants to die.  I'll wait for the carb kit to arrive, then pull it apart and give it a good cleaning. 

Other than that, it clatters a bit.  I seem to recall it needed a crankcase seal or something?  Not sure if I can get engine parts anywhere anymore.  If I can get the carb right, I guess we'll ride it and see what breaks.

Definitely replace the crank seal. 

These always struck me as tge perfect campground/pit bikes.  I'd love to have one on the back over my truck if I was going cross country pulling a trailer. 

1988RedT2 said:

Other than that, it clatters a bit.  I seem to recall it needed a crankcase seal or something?  Not sure if I can get engine parts anywhere anymore.  If I can get the carb right, I guess we'll ride it and see what breaks.

Don't overlook the local Yamaha dealer - it's always worth a try to see OEM parts are still available in the system.  You can find part numbers online at Bike Bandit, among other places.  It appears there are a couple online overseas places that specialize in Chappy parts as well.

Places like babbit's yamaha have all the micofishe on line.  Parts pac and boats net suck from my experience they claim to have parts but then 2 weeks later you get a credit...  At least they don't keep your $$ but i order i want the parts.

Carb kit came yesterday.  True vintage part.  The instruction sheet has patina!

Good to know it still has the stock carby on it.  Hopefully the Chappy will be zooming down my road in a few hours.

Well, not quite the result I was hoping for!  Starts first kick.  Carb is clean as a whistle with a few new gaskets.  Float is (and was) set correctly.

Overall, it seems a little better, but something is most definitely amiss.  It does okay in first gear, but shift to second and try to ride up a small grade, and the engine bogs down, like it's leaning out on anything over part throttle.  It seems quite happy at idle and just above, but will not pull a load.

Not sure what to try next?

EDIT:  I've piddled with it a bit more and it seems pretty good in first. In second I can get it up to about 15 MPH, but it won't take more than maybe half throttle.  And the whole while it's making a rattly, clanky sound that can't be good.  Looks like I'll need to get into it a bit deeper.

Sounds like an air leak.  Crank seal is likely.  Just so I'm not sounding like an idiot...that's a 2 stroke correct?

In reply to doc_speeder :

Yes!  2-stroke.  Originally had an oil pump.  I currently run premix.

Well, I did two things today, and the Chappy is running much better.  Still not what I'd call perfect, but this is a 2-stroke from 1976, so I'm willing to cut it a little slack.

First thing was to go back into the carb, recheck everything, and raise the float level a little.  I felt it was right where it was supposed to be before, but given that it appears to be running lean.... I tweaked it.

Second thing was to jam a screwdriver up the dinky little tube that is the exhaust outlet.  It came out covered in black goo, and I couldn't tell if it was hitting a baffle or some sort of clogged-up obstruction.  I didn't apply enough force to break anything, just maybe knock some stuff loose.  At some point, I may remove the entire exhaust and see if there's any way to clean it out.

Net result is that she runs pretty okay.  She will pull in the lower gears, right up to near WOT.  Progress!  My son gave it a ride and agrees it's much better.

44Dwarf said:

Places like babbit's yamaha have all the micofishe on line.  Parts pac and boats net suck from my experience they claim to have parts but then 2 weeks later you get a credit...  At least they don't keep your $$ but i order i want the parts.

 

Found a part I want at boats.net.  Checked availability and comes back positive.  What are the odds they actually have the part?  I may call.

25% they have it in my experience.   If it's list as NLA on any real dealer site that may drop to 10%...    It's to bad John Groom retired (NWVintage) he had vintage Yamaha stuff done right.

Pull your exhaust pipe, clean the inside by baking it in a BBQ grill or over a fire.  While its Smok'in away grab your exacto knife flip the little guy upside down and roll the piston so the Exhaust port is uncovered scrap clean the top of the port. over time the roof of the port will close up and lead to poor running many bikes get rebuilt before they really need it due to ports closing up that get cleaned out during the overhaul and chalked up to "boy i guess it really did need a top end"

In reply to 44Dwarf :

Ordered from boats.net.  I'll let you know if it ever shows up!

I appreciate the tip on the exhaust.  I'm going to try that.

Having looked at the exhaust connections, it appear to me to be a ring at each connection point that needs to be whacked with a hammer and a pointy thing in order to loosen.  Or is there a more sophisticated method?

Well, something is on its way to me from boats.net.  Shipped from GA on the back of a mule.  Should be here in about a week.

Oh great!  some people have all the luck...  :)

There is a special spanner but a hammer and old dull chisel works fine.

The mule got here this afternoon, just now really.  Looked a little tired, maybe even dehydrated.  He dropped the parts in my mailbox and kept on going.  

I opened the box, wondering if I got a cheap knockoff or the real Yamaha deal.  Let's just say it doesn't take much to make me happy!

Chappy is missing the side stand, until now.

Build and finish on the stand is nice.  I had seen pics of the modern repro selling on ebay, and it was pretty ugly.  Glad to have the OEM part.  Thanks boats.net!

Nice!

The trouble with new OEM parts is now you need to work on making the rest of the bike match all that shiny kickstand goodness. 

edited to add:  I just looked at the boats.net website and they only appear to offer outboard motor parts...Did you just enter the part number for the kickstand, or how did you figure out they also sell bike parts?

In reply to stuart in mn :

Yeah, I think it was one of the hits from gooogle when I searched "side stand" and the part number.  Would have ignored it if not for 44Dwarf's mention of it earlier.

Well, on the exhaust endeavor, I have easily loosened the connector pipe to muffler connection by lightly tapping with a hammer and dull chunk of steel.

Not so on the cylinder side.  A few taps revealed a different sound.  The sound of a well-rusted, frozen hard connection.  I hit it with penetrating oil and will proceed very slowly.  At least I can still bake the muffler.