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Bogging down.
brodsord:
--- Quote from: Nurse Julie on May 12, 2020, 06:23:06 PM ---
--- Quote from: brodsord on May 12, 2020, 06:16:25 PM ---Choke lever*
F@cking iPhone
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.
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Hate predictive text Julie
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K2-K6:
DS have DR8ES listed as NGK plug spec for the K5.
It's worth fitting the equivalent in higher heat range while you work on the jetting. So DR9ES as they are more resistant to the plug tip going over temperature during your mixture exploration phase. It reduces the risk of pre-ignition that could cause damage to the engine.
brodsord:
--- Quote from: K2-K6 on May 13, 2020, 02:09:05 PM ---DS have DR8ES listed as NGK plug spec for the K5.
It's worth fitting the equivalent in higher heat range while you work on the jetting. So DR9ES as they are more resistant to the plug tip going over temperature during your mixture exploration phase. It reduces the risk of pre-ignition that could cause damage to the engine.
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Thanks K2 that’s a very good point.
I’m just taking the carbs of now to see what jets are in there.
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Nurse Julie:
--- Quote from: K2-K6 on May 13, 2020, 02:09:05 PM ---DS have DR8ES listed as NGK plug spec for the K5.
It's worth fitting the equivalent in higher heat range while you work on the jetting. So DR9ES as they are more resistant to the plug tip going over temperature during your mixture exploration phase. It reduces the risk of pre-ignition that could cause damage to the engine.
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David Silver has 'R' plugs suggested for many of our bikes but thats totally the opposite to what the shop manuals / Haynes says. Its a known fact that the original metal shroud HT leads needed resisted plugs but as many of those caps were binned on PDI and rubber (or maybe they are plastic 🤔) resisted caps fitted, non resisted plugs have been fitted as standard since.
brodsord:
--- Quote from: K2-K6 on May 12, 2020, 08:27:09 PM ---As the others have already posted, you can really chase your tail on this sort of stuff.
Basic problem is not that the engine will burn more fuel, but that the original airbox / intake etc cause more vacuum that pulls the correct amount of fuel from the float bowls. Going to pods gives you less vacuum in the carb venturi for the same engine speed, and consequently pulls less fuel up from the float bowls, hence the weak mixture.
As a test / see, you could lift the needle in main jets by dropping the circlip two notches, setting the float height a couple of millimetres higher, turning the idle jets in by 1/4 from standard setting and using resisted spark plugs with resisted HT caps as well.
It would push it toward where you need to be and at least see if it improves without significant cost.
Edit;- also make sure the plugs are at their minimum specified gap too.
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Hi K2,
So I took my carbs off and stripped them down and gave them an overhaul, they were in a shitty condition.
Carb one had a blocked fuel bowl vent so it was probably struggling filling up with fuel, carb four had a broken float pillar.
Sorted both issues and renewed the various seals orings etc as I had some carb seal packs a bought a while back from DSS
Polished up jets and needles with some 600 wet paper.
Fitted needles with clip retainers on the bottom setting as you suggested.
Just did basic eye up setting with slides as I’ll sync them tomorrow.
Pilot jets are 1.5 turns out and pods are on.
So,
I took her for a test ride and she goes like a rocket, no spluttering or bogging down, just goes like the clappers!!
The pilot jet is 40 and main is 105.
I’ve set the spark plugs at .024 and I’ve raised the floats by a couple of millimetres.
I did about 25 miles earlier and I’ve taken the plugs out to see how they look, seem ok
Thanks for your advice
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