Breathing sweet filter

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coaster
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Anyone else had any problems running with one of these? I'm running a Mick Abbey tuned Indian Ally 225 kit and was finding that it was bogging down at around 1/2 to 3/4 throttle. I first lowered the needle but that only made a slight diffence. I then came down on the main from 128 to 125 but there was no change :? I then took the filter off and found that just over 3/4 throttle, all hell broke loose and it took of like a rocket :o
Experimenting with the filter reveled that the elbow on the breathing sweet is very flimsy and the panel squashes it by at least 1/2" (28PHBH) so I was wondering if this is restricting the airlow too much?

As a foot note, I was so facinated when it cleared that I held the throttle open to see what it would do, I bottled out at about 65ish and as soon as I shut the throttle, it nipped up :oops: :roll: By the time I had braked to a stop it had freed off and kicked over and ran fine. Be all right or should I have the barrel off and clean it up? maybe do a bit more jetting first in case it nips again?

Cheers

Oh Dan/Mick I'll give you a full report when it's running better ;)
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Andy Pickering
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Are you running this breathsweet:
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I to have the same symptons of bogging 1/2 -3/4..if you feed it in slowly its fine and goes like a rocket but quickly blipped it does bog down in that throttle range ..Im leaving alone till the lads can fit me in for a dyno as tinkering could or in your case can cause a nip.. :( ..had a very slight nip a few weeks ago so its set back to rich (x13 needle 2nd notch) and after 135 miles riding at weekend and choccy brown plug I shall leave it to the experts (Sean/Dan) mines a stage 4 200 with asso 125 main..BTW
Ricspeed, gone but never forgotten RIP my friend #59
storkfoot
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In my experience it's a lot easier to jet an open mouthed "big" carb, or a carb with a filter straight on the side, than one with an elbow.

Whether it's issues with the pulses hitting the elbow and bouncing back, or whether it's spitback, I don't honestly know. I'm pretty certain with loads of patience you can jet the carb through it, but it does make life hard (I've never tried on the breathing sweet one though). Perhaps a dyno session might be an idea?

Personal opinion, if you've nipped up, I'd take it off and have a look. Otherwise you'll always be thinking..........
Train Driver
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Well someone must like them or they only made half a dozen, i cant find one anywhere
i need it to go with my 30mm keihin and i would like it tomorrow morning please :lol: :lol:
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coaster
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Lam46 wrote:Are you running this breathsweet:
Yes that's the one, I have a 13 litre tank so I've raked it back at about 45 degrees so the sock is just above the fan cowl. Without the panel on, my elbow extends as far as the first rear runner strip :shock:

Paul, yes, I think you're right, I'll set it up without the filter. I will take the top end off before Spain but as there's more than a chance that it could nip up again during the jetting process, I'll leave it for now ;)
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Andy Pickering
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Train Driver wrote:Well someone must like them or they only made half a dozen, i cant find one anywhere
i need it to go with my 30mm keihin and i would like it tomorrow morning please :lol: :lol:
If theres a shortage of these you can have mine for £200... :roll: :frog:
Ricspeed, gone but never forgotten RIP my friend #59
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Doom Patrol
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Just wondering about this breathing sweet business. Do you run the filters dry or not? My understanding is that it's the oil in the foam that traps particles of dirt. I don't think I've seen anyone comment on this.
Train Driver
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Doom Patrol wrote:Just wondering about this breathing sweet business. Do you run the filters dry or not? My understanding is that it's the oil in the foam that traps particles of dirt. I don't think I've seen anyone comment on this.
I would have thought lightly oiled, also i was told two strokes don't work well with wire gauze K&N type filters
soosh
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Ive never got on with one of these and even when jetted correctly,it still strangled the performance so binned it.Im now breathing sweet again.Soon gonna cut a hole in the panel and breath even better.
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coaster
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My manifold is not inclined, it's possible that if it was a downdraft type it could be shortened a bit and maybe aleviate the squashing. In my case though Mick Abbey has packed and re-shaped the inlet mainifold and port to get better flow and if I change the manifold I'll have to sent the whole lot up to him for modding....maybe after the Euro 8-)
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