Is my fuel tap restricting flow at high speed?

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GeeTee
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Re: Is my fuel tap restricting flow at high speed?

Post by GeeTee » Mon Jan 18, 2016 8:15 pm

try running with flap back in place

It's there for a reason

Neosophist
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Re: Is my fuel tap restricting flow at high speed?

Post by Neosophist » Tue Jan 19, 2016 10:04 am

mattvfr400 wrote:I have a speedo converter which i now put on the bike but yet to find an opportunity to pin the throttle on my private ride...so will have to see if it is the restriction...dont know what the restriction would feel like at 113mph...if its a judder/stutter and kicks back on instantly after releasing the throttle then that sounds like it
easy way to tell if it is that is to disconnect the 3 pin plug at the back of the speedo and ride in any gear.. you will get the same feeling over 5500 rpm

also as above.. airbox and ancillaries missing can really mess up the bikes running
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...

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Re: Is my fuel tap restricting flow at high speed?

Post by mattvfr400 » Tue Jan 19, 2016 12:01 pm

richyrd5 wrote:The restrictor drops 2 cylinders at that speed so could be what your describing
I've heard and read about this before. Never bothered with the resister but like I said had a speedo converter laying about. Will have to go for a high speed run this evening and see if I can get passed 113mph!

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Re: Is my fuel tap restricting flow at high speed?

Post by mattvfr400 » Tue Jan 19, 2016 5:54 pm

I believe it was the jap 113 restriction, speedo converter did the job. Got to an indicated 135 before running out of road...obviously I know it's more like 120 but I'm happy I have no issues at high speed anymore. Also about the rubber flap in front of the airbox. I had the whole bike apart the other night and for the life of me I could not work out how it's supposed to fit! I tried every scenario and angle possible and the only one that looked/fitted correctly restricted all air flow! May just be me missing the plot but seems to be spot on for now so won't need anymore tinkering. I've got the bit in my shed so when the bike comes apart next I'll try again. More than likely soon because carbs need a good balance. Cheers away fellas!

richyrd5
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Re: Is my fuel tap restricting flow at high speed?

Post by richyrd5 » Tue Jan 19, 2016 6:07 pm

There's pics in cammos carb rebuild thread at the top of workshop section with pics on how the flap fits

mattvfr400
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Re: Is my fuel tap restricting flow at high speed?

Post by mattvfr400 » Tue Jan 19, 2016 10:48 pm

richyrd5 wrote:There's pics in cammos carb rebuild thread at the top of workshop section with pics on how the flap fits
Cheers!

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JZH
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Re: Is my fuel tap restricting flow at high speed?

Post by JZH » Tue Jan 19, 2016 11:02 pm

Another way to test the restriction is to simply disconnect the speedo cable and go for a ride (on a track, of course). But then you need a GPS or something to tell you if you're past the restriction point! (Or figure out the speed from the gear/rpm.) Glad you got it sorted the easy way!

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JZH

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www.vsource.org

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