Honda CM250 Starter Clutch Issue

Interesting, I will add a hose on there I think I'll have to do another pilot jet clean as well as I just took it out and it won't idle again. I think that is my issue thanks roadghost
 
Was pretty dirty in the pathway, had to clean it out with carb cleaner and a piece of paper towel wrapped around a drill bit. I'm guessing this is why the bike was put away and the head of the pilot jet is so mangled lol
 
mistersouthpaw said:
Was pretty dirty in the pathway, had to clean it out with carb cleaner and a piece of paper towel wrapped around a drill bit. I'm guessing this is why the bike was put away and the head of the pilot jet is so mangled lol
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You can be sure 1000s of those bikes were sold because the owner couldn't figure out why the engine seemed like it was missing. If that vacuum piston gets even a little bit of dust in it, it doesn't move freely and engine performance becomes terrible. Put hose and filter on it and it will do 120km/h all day for 1000s of kms. You'll see what a great little engine it is once you get it tuned up.
 
Oh yea the bike is a hoot I've ridden it quite a bit now..(3 carb cleans now) regarding the hose.. is it part #25 on the carb section of the fiche? I don't understand how it was completely missing from the bike lol

Also thanks to trials and roadghost for pointing out the missing vacuum hose
 
mistersouthpaw said:
Oh yea the bike is a hoot I've ridden it quite a bit now..(3 carb cleans now) regarding the hose.. is it part #25 on the carb section of the fiche? I don't understand how it was completely missing from the bike lol

Also thanks to trials and roadghost for pointing out the missing vacuum hose
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If you go to page 142 of the link to the manual I posted you will see the hose in the diagram. Hose is #10. Clip is #11. On the actual dealer fiche hose is #26 and clip is #25:

1983 Honda CM250C Parts - Best OEM Parts Diagram for 1983 CM250C Motorcycles

All you really need is a piece of 1/4" rubber hose available at Cdn Tire or any auto parts store and a clip to fasten it on. Just make sure it doesn't bend or kink such that the flow of air is blocked. I fasten mine to the frame.
 
The carburetor may very well have the vacuum port integrated within it's own casting, then it would be nothing more then a little hole in the side of the bore and close proximity to the intake valve.
Big benefit of doing a compression test is that you have 2 cylinders drawing from 1 carburetor, you can't balance carburetors to suit the intake but you can make sure the intake vacuum is balanced so that the carb is tuned to work well on both cylinders, if one cylinder has a poorly adjusted valve or whatever you will never get it to run really well.
 
Trials said:
The carburetor may very well have the vacuum port integrated within it's own casting, then it would be nothing more then a little hole in the side of the bore and close proximity to the intake valve.
Big benefit of doing a compression test is that you have 2 cylinders drawing from 1 carburetor, you can't balance carburetors to suit the intake but you can make sure the intake vacuum is balanced so that the carb is tuned to work well on both cylinders, if one cylinder has a poorly adjusted valve or whatever you will never get it to run really well.
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The carb does have a vacuum port, road ghost has pointed it out and I did not notice it because it was so clogged with dirt from having the hose missing. I have cleaned it out well and will get a vacuum hose from FS on tuesday.. not worried about the valves because I just set them and they are perfectly in spec but I'll still test the compression because I picked up a compression tester from princess auto today. Really surprised that it was completely missing from the bike
 
Roadghost said:
If you go to page 142 of the link to the manual I posted you will see the hose in the diagram. Hose is #10. Clip is #11. On the actual dealer fiche hose is #26 and clip is #25:

1983 Honda CM250C Parts - Best OEM Parts Diagram for 1983 CM250C Motorcycles

All you really need is a piece of 1/4" rubber hose available at Cdn Tire or any auto parts store and a clip to fasten it on. Just make sure it doesn't bend or kink such that the flow of air is blocked. I fasten mine to the frame.
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Sweet thanks for your help
 
Roadghost said:
Yeah, if you've already lubed it and all you get is the noise you can disassemble the actual starter and try lubing it or just get a new one.

As for the vacuum hose, I was befuddled because it didn't appear in any of the diagrams of the Keihin carb. I only remembered it because I have one on my Harley. Couldn't understand why 400km after each carb cleaning the bike would sputter under load, and when I opened up the carb it was full of fine dust. Here's where it is:

PICT0903.jpg
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Does the missing hose slide onto a brass nipple? If so, then the OP is missing that off their carb too.


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If it is a vacuum hose it will be connected to your intake manifold somewhere, that is the 'only' place your motor produces a vacuum.

If it is open at one end and either aims upwards to keep out water or downwards to drain out fuel, then you are looking at a drain or vent pipe. (atmospheric pressure)
 
Trials said:
If it is a vacuum hose it will be connected to your intake manifold somewhere, that is the 'only' place your motor produces a vacuum.

If it is open at one end and either aims upwards to keep out water or downwards to drain out fuel, then you are looking at a drain or vent pipe. (atmospheric pressure)
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Agreed. Vacuum lines don't just go from the carb to the ground, they wont produce a vacuum that way. Something sounds wrong. Lol

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Iceman said:
Agreed. Vacuum lines don't just go from the carb to the ground, they wont produce a vacuum that way. Something sounds wrong. Lol

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Trials said:
If it is a vacuum hose it will be connected to your intake manifold somewhere, that is the 'only' place your motor produces a vacuum.

If it is open at one end and either aims upwards to keep out water or downwards to drain out fuel, then you are looking at a drain or vent pipe. (atmospheric pressure)
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I hear you guys - the passage way could be a fuel drain.. it goes to the float bowl. Looking at the fiche it appears that it is a fuel drain

Heres the fiche:
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