1981 Honda CM400C / Rich Running/ Lugge rack

[MnSpring]

Just purchased a 81 Honda CM400C, with 3,500 Original miles on it. and it is very clean!

http://www.tomradde.com/xt225/page1/page1.html

I mostly drive a XT-225, around, but I bought this, because it was clean, runs like a top, and low miles.

Want to watch, and learn, and perhaps ask questions if I need to do anything with this one.

From Minn, 20 miles West of the TC's

Looking for a original Rear Cargo rack,
A Shock Re-Builder, for the soft original ones.

Thanks for your time.

Also Added this after post was moved. - - - - - -

Any opinions of, 'manuals'; Clymer / Haynes / Honda Original Owners, or others?

I do notice after just about 30 miles, in 6 mi +/- trips,
running a bit rich. And higher idle.
Starts, Runs fine,
but I can smell just the slightest amount of gas, when it is idling,
(have found no leaks) And when I stop it,
(Let it idle down, and run, with the petcock off, for about 1/2 a min)
It does a slight backfire.

The PO ran, 'regular' gas in it for years.
Here in Minn, the, 'reg' gas contains from 8 - 12% Ethanol "crumb".
Even the Dealers Don't know, because they don't tell them.
It's suppose to be 10%, but each load is different.
I switched it over to the, 'Non Oxy' gas, which is now only 91 oct.
But NO "crumb" Ethanol in that gas.
(All I use for any 2 cycle, or older 4 stroke motors)

Could the better gas, be causing the, 'rich nes',
or the higher idle ?

When I first got it, before I got all the "crumb" gas out of it,
it was 2,000 RPM
now, 2,000, until about 3-5 miles, then 3,000.

Also, Factory, or like, Mufflers. Place to get?
Looked at JC Whitney, 98% is 'generic', not 'specific'.

I have noticed the ones on it now,
have a small 2" x .125" 'rust' spot, on the bottom,
about 1" from the outlet on both sides.
Which I can feel exhaust coming out of.

Today, I ran it 12 miles, drained the oil, put new oil in,
ran it 40 miles, Drained the oil, put in new oil & Filter.

Going to put in NKG D8EA plugs, gap set .6-.7
(Was Champion RA8HC, which are a bit dark, soot)
I attributed that to not, I Think, going over 40,
and the crapola ethanol gas.

Today at about 35-40 MPH, a 'cough' once in a while,
didn't matter what gear. RPM's about 3500 +/-
Just guessing it was cleaning out the old crapola gas.

Their was a splash of 'old' gas in the tank before I filled it up with Non Oxy gas.
But only have about 80 miles on, with the new gas.

Any input or tips would be appreciated.

Thanks

[Johnj]

Dude that is one clean motorscooter. Howdy and welcome to the forum.

[MnSpring]

Thanks.
Any opinions of, 'manuals'; Clymer / Haynes / Honda Original Owners, or others?

I do notice after just about 30 miles, in 6 mi +/- trips,
running a bit rich. And higher idle.
Starts, Runs fine,
but I can smell just the slightest amount of gas, when it is idling,
(have found no leaks)
And when I stop it,
(Let it idle down, and run, with the petcock off, for about 1/2 a min)
It does a slight backfire.

The PO ran, 'regular' gas in it for years.
Here in Minn, the, 'reg' gas contains from 8 - 12% Ethanol CRAP.
Even the Dealers Don't know, because they don't tell them.
It's suppose to be 10%, but each load is different.
I switched it over to the, 'Non Oxy' gas, which is now only 91 oct.
But NO CRAP Ethanol in that gas.
(All I use for any 2 cycle, or older 4 stroke motors)

Could the better gas, be causing the, 'rich nes',
or the higher idle ?

When I first got it, before I got all the CRAP gas out of it,
it was 2,000 RPM
now, 2,000, until about 3-5 miles, then 3,000.

Also, Factory, or like, Mufflers. Place to get?
Looked at JC Whitney, 98% is 'generic', not 'specific'.

I have noticed the ones on it now,
have a small 2" x .125" 'rust' spot, on the bottom,
about 1" from the outlet on both sides.
Which I can feel exhaust coming out of.

[Fargo360]

I have a CB360T that was running like that until it took a dump. I bought an original Honda Shop Manual on ebay for like $10. What I would do is find someone that can do a leakdown test on it. I'm guessing being an '81 and only having 3500 miles on it, your rings are shot and you have some corrosion on your valves, not enough to screw you up completely, but it doesn't take much. I'd find a gasket kit and a ring kit and do a ring job on the bike and take the head to a place where they can...i can't remember the term for it...but they basically ream the valve head and valve seat together with some diamond dust or something like that and it makes a true mated surface for a good seal. But I would do, or have a leakdown test done on the bike...before you do anything. My bike is a '76 and hadn't been driven since '81...had 6500 miles on it...I chased gremlins for ever...and people on here i'm sure remember...it was painful.

So yeah, leakdown...rings...valves.

So are you from the Waconia area? Chaska, Delano, Elk River? I'm from Winsted, folks live in Annandale now, and I'm up in Fargo...nice to know there are people from my neck of the woods on here.