Vmax Fcr Hanging idle , need help

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VMAX1260

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alright fcr guru's i need some help. checked all vaccum seals which they in very good condition, it does that and without the trottle cables, it is a bit annoying (not bit i am just polite) any been there and tell me what to check . checked the floating bowls, checked all jets , i have dissasmply them over 3 times.
 
Carb sync?

is this possible to happen if the carbs are not synch ? i tried to sync them with measuring the gap with a small drill cause here where i am transferred i cannot find synch carb guage tool anywhere. i removed completely the idle screw and made all slides equal to just fit a tiny drill inside. it was the best i could do. dont how much off they could be
 
I suggest lubing your throttle cables, and be sure you don't have any corrosion in them, or have them too-tight/not-enough slack. You can try doing it with everything hooked-up, but I suggest disconnecting the cables, checking them individually for drag, resistance, and then re-connecting them and make sure you have a few mm of slack. Having them too-tight will give you an erratic idle, and drive you crazy trying to fix it, by 'adjusting' the air needle, cleaning the carbs, adjusting the floats in the bowls, synching, and everything-else, when it's just a matter of too-much tension on the cables. The helix, the spiral jacket in-which the cable runs, can develop corrosion over time, and the corrosion can hang-up the cable(s) so they drag in the outside housing.

I'm not sure if the FCR carbs use the VBoost or not, I think that if you follow the Dynojet Stage 7 directions, and eliminate the butterflies, there is only one type of balancing tool you can use. I think no-butterflies makes the liquid Motion Pro synch tool not work correctly, because you cannot isolate one carb from-another. Dannymax or Sean Morley can probably inform you in more-detail.
 
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I suggest lubing your throttle cables, and be sure you don't have any corrosion in them, or have them too-tight/not-enough slack. You can try doing it with everything hooked-up, but I suggest disconnecting the cables, checking them individually for drag, resistance, and then re-connecting them and make sure you have a few mm of slack. Having them too-tight will give you an erratic idle, and drive you crazy trying to fix it, by 'adjusting' the air needle, cleaning the carbs, adjusting the floats in the bowls, synching, and everything-else, when it's just a matter of too-much tension on the cables. The helix, the spiral jacket in-which the cable runs, can develop corrosion over time, and the corrosion can hang-up the cable(s) so they drag in the outside housing.

I'm not sure if the FCR carbs use the VBoost or not, I think that if you follow the Dynojet Stage 7 directions, and eliminate the butterflies, there is only one type of balancing tool you can use. I think no-butterflies makes the liquid Motion Pro synch tool not work correctly, because you cannot isolate one carb from-another. Dannymax or Sean Morley can probably inform you in more-detail.
as i mentioned it does that also without the throttle cables attached, i contacted pcw gave me some details i checked all jets, float level, needle clips e.t.c new boots on the carbs. no v-boost with fcr, every carb has its on intake to synch it so they are isolated, the thing is i am transfered to an isaland with 7000 people and there is no synch tool anywhere, i synch my fcr carbs as many do, adjusting every slide to let pass through a very small drill . maybe it is a synch problem, i am thinking buying this https://www.carbtune.com/ so i know that my carbs re synched and if the problem i still there to look elsewhere
 
I struggled with them and the drill bit method and simply found it far easier to drill/tap the manifolds and install vacuum parts and do the sync that way.
 

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An idle that does not settle after a throttle blip indicates a lean condition. Check for air leaks (probably the most common cause), if there are none try adding fuel with the fuel screw and turning down the idle speed to an acceptable minimum.
 
From your video it looks like fire-medic may be correct. Certainly looks like the problem may be with the cables or the return spring. They aren't snapping back like mine do. With mine out of adjustment the throttle still snapped back. Definitely check the cables and a little graphite works wonders.
 
update, as i said that does it also without the throttle cables attached. i stripped the again and again installed them again and again , started to isolate one carb from the axle that pulls the vaccum slide, so my engine run on 3 cylinder to see if it was a specific one. and yes it was a specific one, carbs again on the bench and saw the problem. the rollers in the carb was making this has wear the carb body ( made little gaps) , especially in the idle possition were it sits. with the engine running the vacuum is very strong making the rollers to sit in this gaps and struggle to get off them. the carb body is die cast alloy with zinc so no welding can be aplied there, after a tons of research i found many people thinking of making wider rollers to take advantage of the anused carb body, from all those people one actually made the rollers and it worked perfectly, i have already found that guy who owns a cbr 900 rr and gave me some info. today i will take measurment what space i have so i make new ones, i ll posting the procedure so if anyone has a similar problem can resolve it. Sean i wanted to ask you if you have for sell the actual pcw throttle system for these carbs cause my patent throttle cable broke , or if you know what other bike throttles i can use. i do not have the original vmax throttle system on my bike.
 
this is not my body cause i didnt take a pic, but it is exactly like that, the rollers sit in gap and make all the problem
 

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Can you show us what that is from another pic? It's too-close-up, and I don't know what the rollers are supposed to do. So, is that what's causing your problem, and you're just showing us what did it?
 
Can you show us what that is from another pic? It's too-close-up, and I don't know what the rollers are supposed to do. So, is that what's causing your problem, and you're just showing us what did it?
this is the fcr slide , it moves on rollers when going up and down, this rollers make a body wear, usually in the idle possition where it sits more that the open throttle possition. it wear the body and the rollers sit in the gaps they make in the body.
 

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this is the fcr slide , it moves on rollers when going up and down, this rollers make a body wear, usually in the idle possition where it sits more that the open throttle possition. it wear the body and the rollers sit in the gaps they make in the body.
a video from youtube may help you understand the rollders are small wheels that rolls the slide
 
FCR 41 mm flatslides.jpg So the rollers get to wear-out the sides of the throttle body, because they constantly-chafe from the flatslides' reacting to the harmonics of the engine running? Sounds like they need inserts with a similar wear characteristic to the rollers' metal composition/hardness. I assume the rollers are some-sort of steel, and it wears-away the I presume aluminum body of the carb.

That sounds like the sort of problems that the old English Amal carbs used-to have. The throttle slide would wear-out the body. The 'Concentric' Amal carb I believe was a design to greatly reduce that tendency.

A set of 41 MM flatslides waiting to be fitted to a friend's GSXR 1100 Slingshot custom build.
 
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View attachment 68617 So the rollers get to wear-out the sides of the throttle body, because they constantly-chafe from the flatslides' reacting to the harmonics of the engine running? Sounds like they need inserts with a similar wear characteristic to the rollers' metal composition/hardness. I assume the rollers are some-sort of steel, and it wears-away the I presume aluminum body of the carb.

That sounds like the sort of problems that the old English Amal carbs used-to have. The throttle slide would wear-out the body. The 'Concentric' Amal carb I believe was a design to greatly reduce that tendency.

A set of 41 MM flatslides waiting to be fitted to a friend's GSXR 1100 Slingshot custom build.
the rollers are from hard plastic, but the body of the card is not pure alloy is a mixture of alloy+zinc thats why the plastic rollers make grooves in the body, i thought of inserts but have my doubts if it is going to stay there cause of the vacuum. also the grooves are uneven so it is better to fill it with something ??? dont know what. a fix that someone done is to make wider rollers to take advantage the undamage part of the body.
 
the rollers are from hard plastic, but the body of the card is not pure alloy is a mixture of alloy+zinc thats why the plastic rollers make grooves in the body, i thought of inserts but have my doubts if it is going to stay there cause of the vacuum. also the grooves are uneven so it is better to fill it with something ??? dont know what. a fix that someone done is to make wider rollers to take advantage the undamage part of the body.
i was diggin arround and found this ? do you think this can be my solution ?
 
brother on those fcr carbs.. ther is a plate on the slides with a large o-ring ,try fitting the plates upside down , this one caught me out for about a year.. hanging idle constant hanging jetting rejetting.etc u name it.......... hate this bike hate this bike etc etc lol lol. try it upside down slide plates . let us know how u get on
 
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