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Discussion Starter · #1 ·
Now on the last stages of a Honda CB 200 rebuild for a friend, every thing has gone quite well apart from a few issues which were resolved. As the carbs were in very dirty condition we decided to get a repair kit from David Silver Spares ltd which is quite comprehensive kit ( main jet, pilot jet, air screw ,needle ,float valve, gaskets etc) the only thing I am slightly confused about is the needle clip height , in an online manual it pictures the clip being in the third groove from the top however on the bike I am doing the clips were in the first groove from the top? my friend said the bike had run ok prior to the strip down , wondered what your thoughts are on this .The bike is a 1976 UK model.
 

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Usual advice over on the other site is to keep all the original brassware, as the pattern stuff is never quite right.

Raising the needles will lean the mixture at mid to full throttle. Maybe it ran better that way on modern fuel, maybe the float levels weren't right and this was an effort to compensate for rich mixture. Has it got original air filters and silencers, changes there will alter carburation.
 

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Discussion Starter · #3 ·
Thanks for your reply, the exhaust and airbox were standard though the exhausts have now been replaced with replicas as they were rotten, one of the carbs float height was wildly out. Will see how it runs once the tank is back from the sprayers. Have kept all the original brass ware in case of any issues, will be interesting to see how these and many other bikes of this era will run with the new unleaded grade fuel I keep hearing about which is supposedly coming here in the UK in September !
 

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Usual advice over on the other site is to keep all the original brassware, as the pattern stuff is never quite right.

Raising the needles will lean the mixture at mid to full throttle. Maybe it ran better that way on modern fuel, maybe the float levels weren't right and this was an effort to compensate for rich mixture. Has it got original air filters and silencers, changes there will alter carburation.
With respect, Raising carb needles, by lowering the clip will richen the air/fuel mixture, and Lowering the needle by raising the clip will lean the mixture, according to my exhaust gas analyzer. Also the entire rpm range from idle to redline is affected, not just mid to full throttle. HondaJohn, ASE Certified Master Tech, L1 Advanced level emissions specialist certificate, licensed California Smog Check Technician. Honda Motorcycle dealership service tech since 1968. Any Questions?
 

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Discussion Starter · #5 ·
With respect, Raising carb needles, by lowering the clip will richen the air/fuel mixture, and Lowering the needle by raising the clip will lean the mixture, according to my exhaust gas analyzer. Also the entire rpm range from idle to redline is affected, not just mid to full throttle. HondaJohn, ASE Certified Master Tech, L1 Advanced level emissions specialist certificate, licensed California Smog Check Technician. Honda Motorcycle dealership service tech since 1968. Any Questions?
I presume that the UK model bike should have the same needle position as any other country models ? I didn't know if because of different humidity etc in other countries that would make any difference to the needle height ? As I said I was really confused with the setting I found was not expecting to be different to the manual,
 

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With respect, Raising carb needles, by lowering the clip will richen the air/fuel mixture, and Lowering the needle by raising the clip will lean the mixture, according to my exhaust gas analyzer. Also the entire rpm range from idle to redline is affected, not just mid to full throttle. HondaJohn, ASE Certified Master Tech, L1 Advanced level emissions specialist certificate, licensed California Smog Check Technician. Honda Motorcycle dealership service tech since 1968. Any Questions?
Sorry, that was a typo on my part. What I meant to say, raising the needle clip ie putting it into the top notch, would lean the mixture, by dropping the needle.

Fuel, yes, we are supposed to be getting this E10 stuff in the autumn. Apart from possible effects on carburetion, the ethanol content is not good for rubber parts, need to chose replacement fuel hoses carefully. I've already experienced a rotted hose on E5 fuel, now replaced with viton tubing.
 

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Discussion Starter · #7 ·
Do you think it would be aswell to put it back to the to the standard settings?
 

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Personally, I would. At least it gives you a baseline to start from. In the past, I've changed too many things at one go, then wondered why I couldn't get it to run correctly.
 
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