Carb adjustments for bogging

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AMCQ46
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Carb adjustments for bogging

Post by AMCQ46 »

while abusing my old firestorm round Wales at the weekend I noticed that the bike would occasionally bog if I was just slightly in too high a gear when trying to pull round a tight bend in the road. you know, one of those corners that turned out to be a bit tighter than you thought, and as you are scrubbing speed and tipping it in a bit extra, you know that dropping a gear would not be a great idea as it could destabilise the bike this deep into the bend, so you just stay in 3rd and use the torque to lung it out the other side.
I would have been at about 3000rpm and if I opened the throttle too fast it would would often, but not always, bog rather than start pulling back up the revs.

without load, the bike revs cleanly through the range from idle, and the revs drop cleanly without hanging up at any point. so that implies the mixture is about right under those conditions.
I am also pretty sure that I have done the mod where you take the carb overflow pipes out of the support bracket and let them hang down, but I need to go check that, as I was obviously braking on the way into the bends, but not like race track hairpin G forces, this was more trail braking.

fortunately I have the Jack Flash thumb wheel idle air screws, which means I can adjust the idea mixture without tools. so at the lunch break I had a fiddle to see if I could improve it.
so not sure if it was a bit too lean or a bit rich, and also I can't remember if these are fuel screws or air screws, I turned them both 1/2 turn further out.

the result of this I think showed an improvement in the bogging risk trying to lug out of a bend (but I might not have been in exactly the same conditions on the roads in the afternoon!) but now there was a hesitation if I was cracking the throttle open with no load.

so a few questions to the carb fiddlers out there|:

1) are they air of fuel screws?
2) is it normal to have good feeling on no load but bogging with load (and the other way round)
3) do I come back 1/4 turn in to try and get the best of both, or do I try going further in to see if I can make it worse?
4) I have not really noticed this before, but I tend to run the bike above 5000 revs rather than lug it, but is it perhaps a jet a bit blocked from standing or the new E10 fuel?

any thoughts welcome
Last edited by AMCQ46 on Mon Sep 13, 2021 6:39 pm, edited 1 time in total.
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8541Hawk
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Re: Carb adjustments for bogging

Post by 8541Hawk »

They are fuel screws so in is leaner out and out is richer.

Actually sounds like the needles are a touch too high with the symptoms you have listed.

I would try going in 1\2 a turn with the pilot screws and see what happens :thumbup:
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AMCQ46
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Re: Carb adjustments for bogging

Post by AMCQ46 »

8541Hawk wrote: Mon Sep 13, 2021 6:35 pm They are fuel screws so in is leaner out and out is richer.

Actually sounds like the needles are a touch too high with the symptoms you have listed.

I would try going in 1\2 a turn with the pilot screws and see what happens :thumbup:
thanks Hawk, I will try going in a full turn from where I am now so it will be 1/2 turn more lean that I was at the start
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fabiostar
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Re: Carb adjustments for bogging

Post by fabiostar »

AMCQ46 wrote: Mon Sep 13, 2021 6:40 pm
8541Hawk wrote: Mon Sep 13, 2021 6:35 pm They are fuel screws so in is leaner out and out is richer.

Actually sounds like the needles are a touch too high with the symptoms you have listed.

I would try going in 1\2 a turn with the pilot screws and see what happens :thumbup:
thanks Hawk, I will try going in a full turn from where I am now so it will be 1/2 turn more lean that I was at the start
mine was very much like that when i fitted the jessie intake stacks. i turned mine in near half a turn and it cleaned it up so i was running rich. sweet as a nut now.
the older i get,the faster i was :lol:
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AMCQ46
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Re: Carb adjustments for bogging

Post by AMCQ46 »

I have not ridden it yet, but put the screws in 1 turn from their new position ... a 1/2 turn from the original setting.

that had the front screw 1/4 from fully in and the back about 1/2.

so will see what that's like at the weekend
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mjvw
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Re: Carb adjustments for bogging

Post by mjvw »

Any links in UK to purchase Jack Flash thumb wheel idle air screws or other makes available?
Sound like a handy upgrade.
:D
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AMCQ46
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Re: Carb adjustments for bogging

Post by AMCQ46 »

mjvw wrote: Fri Sep 17, 2021 5:44 am Any links in UK to purchase Jack Flash thumb wheel idle air screws or other makes available?
Sound like a handy upgrade.
:D
not seen anybody doing these in the UK, I think I imported about 5 sets from the USA when I used to travel back and forth for work, but they were all preordered by members on here, and it was years ago... I don't go on the super hawk forum these days so I don't even know if jack flash is still making them
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8541Hawk
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Re: Carb adjustments for bogging

Post by 8541Hawk »

I can get the word out you guys are looking even though I'm not allowed on that forum..... :lol: and also help with shipping as needed :shh: :lol:
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8541Hawk
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Re: Carb adjustments for bogging

Post by 8541Hawk »

Advantage of being in the secret OCMD club....lol
Here is your answer:

Yes they are available and you just need to contact Josh directly at: tickleherg at gmail.com :thumbup:

Replace the "at" with "@" and no spaces.
They call me "Mr. Flat Earther"
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