Another Carb tuning question

Getting your blazingly fast Suzuki powerplant to perform even better!

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tz375
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Re: Another Carb tuning question

Post by tz375 »

The problem was first identified decades ago on RD Yamahas where fitting pods with metal end caps made life miserable. Use pods with foam end caps so that the pulses do not bounc off them causing reversion and multiple passes through the carb and super rich mixtures.

We have been fitting pods for years and some bikes respond well and others are impossible. I fitted foam UNI filters to a GT750 with CV carbs and the fueling was fine after some adjustment on the dyno with gas analysis.
sportston
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Re: Another Carb tuning question

Post by sportston »

in reply to Connor's post:-
Ok I should explain i meant completely strip the carb then blow out on an airline. Why would anyone blow out a carb while still assembled? That would be crazy. lol. And yes before doing so it is not a bad idea to presoak it. Also recheck float level when rebuilding carbs.

Ignition primaries... I didn't notice that Sharky mentioned he had electronic ignition. However, the problem you identified with modern condensors is a valid one, but It is still worth replacing the old ones with new providing you use quality parts. Intermotor is ok, but avoid CI. It is similar with spark plugs. Use cheap rubbish and you are asking for trouble. The best easily available plugs are NGK. It is not impossible to get a faulty NGK plug but it is very rare in comparison to Champion and other poorer quality plugs. NGK also deliver a better quality spark for longer, with lower voltage loss over time. So many times I have seen customers who had fitted new points only to neglect fitting a new condensor and the resultant poorly suppressed waveform visible on the oscilloscope was appalling. It also leads to seriously shortening the lifespan of your points.

Setting timing...On any vehicle you cannot accurately tune a carb unless your ignition is set and working well. Trust me on this, when I was doing engine tuning for a living, I was ranked amongst the top Cryton Approved Technicians in the country. I do have some experience. Badly adjusted timing, especially on a 2-stroke, can lead to overheating, holes in pistons and poor power delivery etc. Even if you have a forgiving engine, why would you not spend a few short minutes setting it correctly? Once set, electronic ignition should stay set, unless removed such as when you do an engine rebuild.

Inline fuel filters...are a must. I agree it is a good idea to have a clean tank, but you can have a spotless tank and still get dirt in your carbs from the fuel you put in it. It only takes one tiny bit of dirt to cause running problems. For the sake of a few quid it is worth avoiding the hassle.

Battery Voltage...you raise a good point. It is a good idea to check battery and charging voltage.

Ok, I think that covers all the points Connor brought up.
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tz375
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Re: Another Carb tuning question

Post by tz375 »

Instead of float level, I prefer to set fuel level whenever there is any question as to whether or not it is appropriate. It means acquiring a suitable adapter or modified float bowl but is well worth the extra step.
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ConnerVT
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Re: Another Carb tuning question

Post by ConnerVT »

sportston wrote:in reply to Connor's post:-
Ok I should explain i meant completely strip the carb then blow out on an airline. Why would anyone blow out a carb while still assembled? That would be crazy. lol.
There are quite a few people out there, to whom "Cleaning the carb" is spraying everything you can see with a can of Gumout. Removing the carb first is optional.

People of all experience levels visit this forum. I try to be sure the advice I'm associated with is as specific as possible, not assuming anything.
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Suzukidave
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Re: Another Carb tuning question

Post by Suzukidave »

True enough Conner , i makes ya wonder how many "cleaned" carbs never even have the needle jet or pilot jet removed for cleaning ?
the older i get the faster i was
sportston
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Re: Another Carb tuning question

Post by sportston »

Ok, I was somewhat exhausted when i wrote the original reply before falling asleep. In future I will try to cover all possible outcomes due to ignorance.
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