Rookie with a 1967 CB160

[teazer]

Rich, are you carbs from a sloper 175 in which case they are the same size or a vertical 175 in which case they are slightly smaller.

According to our notes, slopers have a 20mm diameter slide and uprights are 18mm plus there is a small difference in bore dimensions.

 

[Big R]

The carbs of mine are from a 68 175 - so sloper.

I would like to hear / see the reasoning behind his slides not sliding though. Only thing i can think of is they are from different carbs.......

 

[Kyzer]

The carbs of mine are from a 68 175 - so sloper.

I would like to hear / see the reasoning behind his slides not sliding though. Only thing i can think of is they are from different carbs.......

So I started sanding the hell out of the insides of the bores, and wouldn't you know it. The slides slid right through like they were knew. I am guessing that they had sit for awhile and the carbon built up to an unreal level. So I put the carbs back together and put everything back on the bike and cranked it. Cranked right up!! And then for some reason my left float bowl started to overflow. For crying out loud!! I am trying not to curse, but damn. if it isn't one thing, it is another.

Got any ideas why the float bowl overflowed?

 

[Big R]

Most likely the float itself is probably sucking gas and sinking.

Does it overflow right away? That would be the float set at the wrong height or a cracked overflow tube.

 

[Kyzer]

Most likely the float itself is probably sucking gas and sinking.

Does it overflow right away? That would be the float set at the wrong height or a cracked overflow tube.

It happened about 10 seconds after I got it cranked. does that mean I have to replace it, or can I set it to a different height?

thanks,
You guys are quickly becoming the new heroes in my life.

 

[Big R]

If it's sucking gas, it will need replaced (or brazed, but I would replace IMO). Pull the float out and shake it lightly - if you can hear a little gas in there, it's buggered.

 

[Kyzer]

If it's sucking gas, it will need replaced (or brazed, but I would replace IMO). Pull the float out and shake it lightly - if you can hear a little gas in there, it's buggered.

I took the float out and it didn't have any holes or dents on it, and there was no sound of gas. When I turned the gas on and tried to crank it, gas still poured out. For the love of God, Why?!

And, on my cb200t, I have gas, the spark plugs are clean and the battery is turning the motor, but nothing is cranking. How can I be so lucky as to have to bikes not working?!

 

[Big R]

Welcome to the wonderfull world of vintage motorcycles!

There may be a tiny hole in the float, so you could even hold it in a glass of water - bubbles would rise out if there's a hole in it. But assuming there's no leak in the float, it could be 1) the float needle is upside down 2) floats set at the wrong height 3) little bit of crud above the float needle allowing gas to come up or 4) there's a crack in the float bowl near the drain tube.

The CB200 - do you have compression (around 150 psi) and have you visually checked for spark? There could be a couple things stopping it from running, we'll need some more info on that one.

 

[teazer]

Float bowls leaking are probably - in no particular order

Leaky floats
Badly adjusted floats
Floats hanging up on a gasket
Bent floats
Dirt in the valve under the float
Sticky float needle
Cracked overflow tube
Missing float needle

Remove the floats carefully and check it over. Then remove the complete needle valve assembly (it unscrews) and make sure it's spotlessly clean and that the needle in it is OK. Check it under a magnifying glass. If that's all OK check the thin tube coming up from the bottom of the bowl for tiny cracks.

 

[Kyzer]

Welcome to the wonderfull world of vintage motorcycles!

There may be a tiny hole in the float, so you could even hold it in a glass of water - bubbles would rise out if there's a hole in it. But assuming there's no leak in the float, it could be 1) the float needle is upside down 2) floats set at the wrong height 3) little bit of crud above the float needle allowing gas to come up or 4) there's a crack in the float bowl near the drain tube.

The CB200 - do you have compression (around 150 psi) and have you visually checked for spark? There could be a couple things stopping it from running, we'll need some more info on that one.

The cb160 was missing the float valve seal. I guess it fell out while I was cleaning it. I have another one being ordered.

The 200 has new plugs but I don't know how to check the compression. Rookie stamp on my forehead.

 

[teazer]

To check compression is quite easy. It require one piece of equipment - a compression tester, which are not too expensive, but you need to get a hose or adapter to fit those 12mm plugs - most come in either 10mm or 14mm.

Remove both plugs.
Turn off fuel
Screw adapter/hose into one plug hole.
Open throttles wide
Crank motor over on electric or by foot and watch the gauge. After 5 or so rotations it should stop rising.
Repeat on other side
We want to see the same number on both sides +/- 10%

 

[Big R]

You forgot the choke - it needs to be wide open along with the throttle.

 

[Kyzer]

You forgot the choke - it needs to be wide open along with the throttle.

Hope you had a happy Thanksgiving. I did until I started working on the bike again. I got the cars working and the bike now runs. Except for some reason my starter stays on. I put a new battery in and when I turned on the ignition. It cranked up, and the starter kept spinning.

The only way I can get my starter to turn off is by turning off the bike. Imagine my heartbreak.

 

[Big R]

If you have a multi-meter, than your starter problem should be fairly painless. Somewhere in the circuit is a constant positive connection. Either in the switch or a melted / loose wire.

Or take the whole mess off and make it kickstart only......

 

[Kyzer]

If you have a multi-meter, than your starter problem should be fairly painless. Somewhere in the circuit is a constant positive connection. Either in the switch or a melted / loose wire.

Or take the whole mess off and make it kickstart only......

Where is the mess located?

 

[Big R]

Get yourself a wiring diagram - but removing the starter may be a little much for you right now. Try and find out why it's constantly running, than maybe later you can see about doing away with it.