Fuel tap vacuum bypass general consensus...
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- CMSMJ1
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Re: Fuel tap vacuum bypass general consensus...
If it was called the Shitty wanker fuel tap mod, no-one would bother
I don't like it and have never had stavration. I have had hydraulic lock and a shitty replacement of oil before I sorted my carbs and original tap out.
A dry break line in the main fuel line is the daddy of all solutions.
So, for me..don't do it. if you do, it will leak in your motor one day.

I don't like it and have never had stavration. I have had hydraulic lock and a shitty replacement of oil before I sorted my carbs and original tap out.
A dry break line in the main fuel line is the daddy of all solutions.
So, for me..don't do it. if you do, it will leak in your motor one day.
IMPERATOR REX ANGLORUM
The V4 is the law..
NC30 - No9 - my old mate
The V4 is the law..
NC30 - No9 - my old mate
- Cammo
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Re: Fuel tap vacuum bypass general consensus...
CMSMJ1 wrote:A dry break line in the main fuel line is the daddy of all solutions.

Perform the hrc tap mod at own risk if you don't fit one of these!
"It's just a ride" Bill Hicks
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Re: Fuel tap vacuum bypass general consensus...
This mod shouldnt make any difference at idle so I find it hard to believe it revs up better unless your fuel tap / vaccumn line was so buggard it wasn:t opening the tap, but then if it didn:t rev up at idle it wouldnt run, it certainly sounds like a case of the placebo effect, such as filling up with vpower.triniriderz.com wrote:Ok did the HRC mod today (only bit of HRC on the bike) and straight away the throttle response was better with nice crisp rev up..
I cheacked that the tap diaphram was sealed when doing the mod and that the tap doesnt leak when in the off position so hopingeverything works out.. I wasnt able to get out on the bike as it is raining real bad and im made of suger so will hope out within the next few days
...
Im not sure if it was clear in my other post but the HRC mod is only of benefit to a specific condition, extended use of WOT (Wide Open Throttle)
Lets not forget the HRC bikes have massive jets in comparision with the road going version and use a lot more fuel.
The diaphram when fully open blocks a small portion of the fuel tap so limits maximum fuel flow to the carbs, on a race bike at full throttle (such as a long striaght) it is possible to empty the fuel from the carbs faster than they can fill up. Which is where the little bit extra from modding the fuel tap comes into play.
I thought I experienced this on my NC24 on a long motorway stretch but after looking at the vaccum hose I believe it was that collapsing in on itself, itd be interesting to see if you can actually run the carbs out of fuel on a standard setup, (ride an NC30 flat out down a long stretch of road and see if it stutters and missfires)
xivlia wrote:i dont go fast on this bike so really do not need a rear brake.. /
vic-vtrvfr wrote:Ask xivlia for help, he's tackled just about every problem u could think of...
- CMSMJ1
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Re: Fuel tap vacuum bypass general consensus...
Holy Placebo Effect Batman!!



IMPERATOR REX ANGLORUM
The V4 is the law..
NC30 - No9 - my old mate
The V4 is the law..
NC30 - No9 - my old mate
- Trinirides
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Re: Fuel tap vacuum bypass general consensus...
Neosophist wrote:This mod shouldnt make any difference at idle so I find it hard to believe it revs up better unless your fuel tap / vaccumn line was so buggard it wasn:t opening the tap, but then if it didn:t rev up at idle it wouldnt run, it certainly sounds like a case of the placebo effect, such as filling up with vpower.triniriderz.com wrote:Ok did the HRC mod today (only bit of HRC on the bike) and straight away the throttle response was better with nice crisp rev up..
I checked that the tap diaphram was sealed when doing the mod and that the tap doesnt leak when in the off position so hopingeverything works out.. I wasnt able to get out on the bike as it is raining real bad and im made of suger so will hope out within the next few days
...
Im not sure if it was clear in my other post but the HRC mod is only of benefit to a specific condition, extended use of WOT (Wide Open Throttle)
Lets not forget the HRC bikes have massive jets in comparision with the road going version and use a lot more fuel.
The diaphram when fully open blocks a small portion of the fuel tap so limits maximum fuel flow to the carbs, on a race bike at full throttle (such as a long striaght) it is possible to empty the fuel from the carbs faster than they can fill up. Which is where the little bit extra from modding the fuel tap comes into play.
I thought I experienced this on my NC24 on a long motorway stretch but after looking at the vaccum hose I believe it was that collapsing in on itself, itd be interesting to see if you can actually run the carbs out of fuel on a standard setup, (ride an NC30 flat out down a long stretch of road and see if it stutters and missfires)
Well after the first 6 miles of the ride it had fuel starvation when reving.. I brought the bike back and at idle it was reving but not as crisp as it should i.e nearly dying after rev up or moving forward 10 meters, I hooked up a Aux fuel bottle and straight away the bike was running better..
I could easily go about refreshing the fuel tap and fitting a new vacuum line but im fucked if im spending another penny on a motorcycle for the next few months and the fuel tap conversion seems to have done the trick as a 30mile round trip today confirmed..
A visual inspection of the vacuum line didn't show any signs of splitting or going bad so my guess would be a issue with the spring in the tap it's self, but the investigation will have to wait for another day when I dont want to ride....
I have had the fuel starvation that Honda talk about on track but it makes the bike far from unrideable and is at best a minor issue for the average track rider and have never had any issue's when on the road..
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Re: Fuel tap vacuum bypass general consensus...
Neosophist wrote:This mod shouldnt make any difference at idle so I find it hard to believe it revs up better unless your fuel tap / vaccumn line was so buggardtriniriderz.com wrote:Ok did the HRC mod today (only bit of HRC on the bike) and straight away the throttle response was better with nice crisp rev up..
I cheacked that the tap diaphram was sealed when doing the mod and that the tap doesnt leak when in the off position so hopingeverything works out.. I wasnt able to get out on the bike as it is raining real bad and im made of suger so will hope out within the next few days
...
xivlia wrote:i dont go fast on this bike so really do not need a rear brake.. /
vic-vtrvfr wrote:Ask xivlia for help, he's tackled just about every problem u could think of...
- Cammo
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Re: Fuel tap vacuum bypass general consensus...

The fuel tap fills the carb float bowls, it doesn't deliver fuel to the engine in any way!
"It's just a ride" Bill Hicks
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Re: Fuel tap vacuum bypass general consensus...
LOL at the subconscious flaming this poor kid is getting.
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Re: Fuel tap vacuum bypass general consensus...
I don't think anyone is knocking him, there must have been another problem before, so best be aware of the facts.
Dave.
Dave.
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Re: Fuel tap vacuum bypass general consensus...
I was not personally saying everyone was ragging on him.
I just found the 3 or 4 consecutive posts amusing.
I just found the 3 or 4 consecutive posts amusing.