Newboy
Re: Newboy
Is it just a case of replacing the pilot jets - i ask as that can be done with the carbs still on the bike?
Re: Newboy
Carbs have to come off.polar wrote:Is it just a case of replacing the pilot jets - i ask as that can be done with the carbs still on the bike?
Old enough to know better.
- Moise
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Re: Newboy
Yes, best to remove the carbs. You could leave the throttle cables on and turn the carbs 90° but I wouldn't recommend it.newsh wrote:Carbs have to come off.polar wrote:Is it just a case of replacing the pilot jets - i ask as that can be done with the carbs still on the bike?
Jompy raves on about how much better the 5jj carbs are. The pilot jets are the only difference and I hate to say it, but he's right.
"You don't get slower with age, you just get more cautious." Michael Rutter
1999 4xv in blue
1999 4xv in blue
Re: Newboy
I don’t understand why people see a big difference with the carbs was it just the 98 r1 that had carb issues?Moise wrote: Sun Apr 22, 2018 8:15 amYes, best to remove the carbs. You could leave the throttle cables on and turn the carbs 90° but I wouldn't recommend it.newsh wrote:Carbs have to come off.polar wrote:Is it just a case of replacing the pilot jets - i ask as that can be done with the carbs still on the bike?
Jompy raves on about how much better the 5jj carbs are. The pilot jets are the only difference and I hate to say it, but he's right.
Are you all running standard carbs. I never noticed a lack of midrange on the 99 4xv mine would lift the front off the throttle and I’m the wrong side of 19stone and that was standard carbs!! I dynojeted my carbs fairly early on then had the airbox mods done when I had a full system fitted. Then it really was batshit crazy!
- jompy
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Re: Newboy
It wasn't a problem and my 4xv with the #17.5 pilot jets would lift the front no problems but the #15 pilots give a meatier midrange and let's face it who doesn't want more midrange ?
Mark you can always try my bike before you touch yours , taking the carbs off is quite easy
Mark you can always try my bike before you touch yours , taking the carbs off is quite easy

- Moise
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Re: Newboy
Most of us are running standard carbs and headers.
I don't understand how dropping 2.5 on the pilots affects the mid-range so much. I have to be careful powering out of long corners, otherwise can end up doing stupid speeds! It runs much cleaner at small throttle openings also.
As you've had your carbs rejetted, it's probably not something you'd want to do. Do you know what jets were changed? Did they lower the float level?
All 4xv's have the 17.5 pilots.
I don't understand how dropping 2.5 on the pilots affects the mid-range so much. I have to be careful powering out of long corners, otherwise can end up doing stupid speeds! It runs much cleaner at small throttle openings also.
As you've had your carbs rejetted, it's probably not something you'd want to do. Do you know what jets were changed? Did they lower the float level?
All 4xv's have the 17.5 pilots.
"You don't get slower with age, you just get more cautious." Michael Rutter
1999 4xv in blue
1999 4xv in blue
Re: Newboy
Of course, since this has been known about since 1999-2000 (yes it will soon be 20 years) many bikes have already had them changed.Moise wrote:Most of us are running standard carbs
All 4xv's have the 17.5 pilots.
On high milers the needle jets wear (they’re brass) and bring on a while load of richness, especially if DJ needles were fitted as they’re abrasive. This can be compensated to a certain extent by dropping the fuel level a mm or 2.
Importantly, if the exup is not closing right you can get rich running too, opposite to what you’d think but it’s true.
Old enough to know better.
Re: Newboy
No. Heavy airbox mods breathers from carbs re routed into the airbox massive hole in the airbox. It was setup for trackdays. It was able to rev much faster than standard but you had to be in the right gear below 4K or it bogged down. The carbs will be stripped soon (if I get a day off) so I’ll take a few picks it’s going to be a sh!t job I know.Moise wrote: Sun Apr 22, 2018 3:55 pm Most of us are running standard carbs and headers.
I don't understand how dropping 2.5 on the pilots affects the mid-range so much. I have to be careful powering out of long corners, otherwise can end up doing stupid speeds! It runs much cleaner at small throttle openings also.
As you've had your carbs rejetted, it's probably not something you'd want to do. Do you know what jets were changed? Did they lower the float level?
All 4xv's have the 17.5 pilots.
- jompy
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Re: Newboy
All I know is that my 4xv carbs have #17.5 pilots and 132 mains and the 5jj carbs have #15 pilots and 132 mains and the 5jj carbs have bags more midrange
Re: Newboy
Must be a hoot on the fighter with your weight further back don’t suppose you get through many front tyres Jompy.jompy wrote: Sun Apr 22, 2018 5:58 pm All I know is that my 4xv carbs have #17.5 pilots and 132 mains and the 5jj carbs have #15 pilots and 132 mains and the 5jj carbs have bags more midrange


- jompy
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Re: Newboy
You calling me fatDanf1 wrote: Sun Apr 22, 2018 7:00 pmMust be a hoot on the fighter with your weight further back don’t suppose you get through many front tyres Jompy.jompy wrote: Sun Apr 22, 2018 5:58 pm All I know is that my 4xv carbs have #17.5 pilots and 132 mains and the 5jj carbs have #15 pilots and 132 mains and the 5jj carbs have bags more midrange![]()
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Re: Newboy
Nope a man of my size doesn’t call anyone fat.jompy wrote: Sun Apr 22, 2018 7:49 pmYou calling me fatDanf1 wrote: Sun Apr 22, 2018 7:00 pmMust be a hoot on the fighter with your weight further back don’t suppose you get through many front tyres Jompy.jompy wrote: Sun Apr 22, 2018 5:58 pm All I know is that my 4xv carbs have #17.5 pilots and 132 mains and the 5jj carbs have #15 pilots and 132 mains and the 5jj carbs have bags more midrange![]()
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- jompy
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Re: Newboy
Danf1 wrote: Sun Apr 22, 2018 7:51 pmNope a man of my size doesn’t call anyone fat.jompy wrote: Sun Apr 22, 2018 7:49 pmYou calling me fatDanf1 wrote: Sun Apr 22, 2018 7:00 pmMust be a hoot on the fighter with your weight further back don’t suppose you get through many front tyres Jompy.jompy wrote: Sun Apr 22, 2018 5:58 pm All I know is that my 4xv carbs have #17.5 pilots and 132 mains and the 5jj carbs have #15 pilots and 132 mains and the 5jj carbs have bags more midrange![]()
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Was gonna say fat cunts a bit of a mouthful so just call me cnut it's easier

Re: Newboy
We’d have to be mortal enemies before I used that one on you paljompy wrote: Sun Apr 22, 2018 7:56 pmDanf1 wrote: Sun Apr 22, 2018 7:51 pmNope a man of my size doesn’t call anyone fat.jompy wrote: Sun Apr 22, 2018 7:49 pmYou calling me fatDanf1 wrote: Sun Apr 22, 2018 7:00 pmMust be a hoot on the fighter with your weight further back don’t suppose you get through many front tyres Jompy.jompy wrote: Sun Apr 22, 2018 5:58 pm All I know is that my 4xv carbs have #17.5 pilots and 132 mains and the 5jj carbs have #15 pilots and 132 mains and the 5jj carbs have bags more midrange![]()
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Was gonna say fat cunts a bit of a mouthful so just call me cnut it's easier![]()

- R1Clarky
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Re: Newboy
m8 his tyres go past their use by date long before their worn out cos he never rides tha fukkaDanf1 wrote:Must be a hoot on the fighter with your weight further back don’t suppose you get through many front tyres Jompy.jompy wrote: Sun Apr 22, 2018 5:58 pm All I know is that my 4xv carbs have #17.5 pilots and 132 mains and the 5jj carbs have #15 pilots and 132 mains and the 5jj carbs have bags more midrange![]()

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