Author Topic: Honda H100 saga need help with carb jet adjustment  (Read 299 times)

Offline kairos

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Honda H100 saga need help with carb jet adjustment
« on: July 08, 2017, 11:20:57 AM »
Hi all,

What a quite forum this is ! I am gradually making progress with my H100. It now runs of sorts. I have no air filter and can't source one locally but the main problem is once I get the engine running I need huge amounts of throttle to keep it running and after about a minute it dies regardless of what setting I put on the idle or main jet adjustment screws.( Main jet  I think is the   screw near the orifice of the carb and the idle has a spring behind it. I started with about 1 1/4 turns on the main jet and 2 1/2 turns on the idle screw).
I have cleaned the carb .

Sorry Rex still no manual :-[

All suggestions gratefully accepted

Richard


Offline L.A.B.

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Re: Honda H100 saga need help with carb jet adjustment
« Reply #1 on: July 08, 2017, 07:30:41 PM »

 I put on the idle or main jet adjustment screws.( Main jet  I think is the   screw near the orifice of the carb and the idle has a spring behind it. I started with about 1 1/4 turns on the main jet and 2 1/2 turns on the idle screw).

One will be the 'throttle stop' screw, this generally has a flat or 'blunt' end and is used to increase or decrease the idle speed by raising or lowering the throttle slide.

The other screw is for adjusting the idle speed mixture This 'mixture' or 'pilot' screw normally has a pointed end.

The main jet is inside the carb float bowl and isn't affected by adjustment of either screw. 

https://www.cmsnl.com/honda-h100s-1986-g-england_model19494/partslist/E__1000.html



L.A.B.

Offline kairos

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Re: Honda H100 saga need help with carb jet adjustment
« Reply #2 on: July 09, 2017, 09:52:17 AM »
Hi L.A.B.
Thanks for your explanation of what the throttle screws are. I can keep the engine running by running the engine fast (plenty of throttle) but the minute I throttle back the engine dies. The original sponge filter fell to pieces when I took it out so maybe the filter acts as a choke? The parts page you sent me  was issued by CMS in the Netherlands I will contact them and see if they have a filter
as I can't source one in Uk.
Thanks again,
Richard

Offline Rex

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Re: Honda H100 saga need help with carb jet adjustment
« Reply #3 on: July 09, 2017, 10:27:21 AM »
Before spending more money on guesswork, I'd check the pilot jet circuit as it sounds like it's blocked.

Offline kairos

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Re: Honda H100 saga need help with carb jet adjustment
« Reply #4 on: July 10, 2017, 10:08:44 AM »
Ok Rex,
Will do.
Richard

Offline kairos

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Re: Honda H100 saga need help with carb jet adjustment
« Reply #5 on: July 10, 2017, 12:46:05 PM »
I have now removed the carb  (again)cleaned it and put it back on the bike and it started first time and throttled up OK. Sat on the bike and selected first gear and it died! Now I am back to square one.

I am just on my was to get an inline petrol filter. I will clean the carb yet again and see what happens.
it is rather frustrating. oh and I did flush the old petrol out before filling up with the new petrol but apparently modern petrol can loosen any old crud left in the tank.

Richard

Offline Rex

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Re: Honda H100 saga need help with carb jet adjustment
« Reply #6 on: September 11, 2017, 09:50:59 AM »
Don't keep us waiting Richard!
How's it going now?