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Discussion Starter #1
i just finished putting in the bigger 125 mains and 20 pilots, did 2 shims on the needles and adjusted the PMS to about 2.9 turns.... now its running shittier than ever...at first it was over flowing with gas, but now it starts fine without the choke, when I engage the choke it dies.... then if I shift to 1st gear and try to take off it really struggles to go and after its going it starts to bogg... what could be the issue here??.. am I missing something?... any advice is appreciated:eek::eek::eek:!! thanks
 

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Did you put the mains and pilots in the right places? Are the needle holders seated correctly? You've definitely got something put together incorrectly. It could be many different things....
 

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Discussion Starter #3
Did you put the mains and pilots in the right places? Are the needle holders seated correctly? You've definitely got something put together incorrectly. It could be many different things....

yeah, everything went into place correctly.....could it be too rich now?? or maybe the floats stuck??/
 

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The only thing you changed were the main jets and added a shim to the needles. The mains only come into use at over 1/2 throttle on up and the needles at about 1/4 throttle.

To me that indicates that your issue is probably with the needles....or that you put the main jets where the pilots should go and vice versa.

You really shouldn't be that rich with that intake and full pipes. However, we are kind of taking an educated guess on the jetting for your intake. From my experience with others using close to the same set up...the jetting shouldn't be that far off. However, we aren't there to actually see everything you have. You could put the stock jets back in, leave the shim on the needles and see what happens.

If it was me, I'd get back into the carbs and double check the reassembly....did you use the stock pilots like suggested?
 

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What made you think you needed to re-jet in the first place? Was the bike giving you problems? Usually, when making these sorts of changes, it is recommended to make only one change at a time, and record the results. Then you will actually have a "paper trail" you can use to learn whether you made it better or worse with each change.
 

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Discussion Starter #6
The only thing you changed were the main jets and added a shim to the needles. The mains only come into use at over 1/2 throttle on up and the needles at about 1/4 throttle.

To me that indicates that your issue is probably with the needles....or that you put the main jets where the pilots should go and vice versa.

You really shouldn't be that rich with that intake and full pipes. However, we are kind of taking an educated guess on the jetting for your intake. From my experience with others using close to the same set up...the jetting shouldn't be that far off. However, we aren't there to actually see everything you have.

If it was me, I'd get back into the carbs and double check the reassembly....


Thats what im gonna do today.....im gonna take it apart again, mains and pilots both went into the right places...., im thinking the issue is gonna be in the floats , might have gotten moved from adjustment last time i took the carbs apart....i will double check again
 

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What made you think you needed to re-jet in the first place? Was the bike giving you problems? Usually, when making these sorts of changes, it is recommended to make only one change at a time, and record the results. Then you will actually have a "paper trail" you can use to learn whether you made it better or worse with each change.
When you change the intake and exhaust you usually need to alter the jetting. That is why he is changing them. These 1100's are not so complicated that you should need to guess. We've got enough recorded data to get them damn close just by knowing what intake and exhaust are being used. No rocket science needed.
 

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Discussion Starter #8
When you change the intake and exhaust you usually need to alter the jetting. That is why he is changing them. These 1100's are not so complicated that you should need to guess. We've got enough recorded data to get them damn close just by knowing what intake and exhaust are being used. No rocket science needed.


What has me confused is that it fires right up no choke needed but when i put the choke on it dies.....i give the bike throttle and it throttles good while standing, its when I get it going in gear that starts to act up.....what would make it die when engaging the choke??:confused:
 

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More gas needs more air!
 

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Discussion Starter #11
Ive took the carbs apart and inspected them once again, floats move freely and look good, jets are good, swapped the 20 pilots back to stock and put it back together, now the choke works but its still running sluggish when i first open the throttle to get it going on 1 gear.... could it be the shims on the needle??... remove one? i have the PMS set to almost 3 turns, should i bring it back down to 2.5?
 

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I'd start the PMS at 2 turns for stock PMS screws. The needles come into play about 1/3 throttle to 3/4. If that's where the issue is, yes take the shim out. It sounds like the issue is just coming off idle. That is pilots and PMS. The 20 pilots would have been way too rich and probably caused the issue you had earlier.

How does the bike run at 1/3 throttle on up?
 

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Discussion Starter #13
I'd start the PMS at 2 turns for stock PMS screws. The needles come into play about 1/3 throttle to 3/4. If that's where the issue is, yes take the shim out. It sounds like the issue is just coming off idle. That is pilots and PMS. The 20 pilots would have been way too rich and probably caused the issue you had earlier.

How does the bike run at 1/3 throttle on up?


1/3 and up seems to run fine from what i felt... its the first 1/4 that struggles, then when i let it rip it and it seems to start go gain the power back up....right now it has 2 shims, so ill go down to one and do 2.5 on the PMS see if that helps... another thing i noticed is that the bottom float cover is really hard to get back on, seems too snug where the main jet goes, is that normal?
 

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If there is an O ring around the main jet holder.....remove it. Make sure that the little O ring on the top of the diaphragm is in place.
 

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Discussion Starter #15
If there is an O ring around the main jet holder.....remove it. Make sure that the little O ring on the top of the diaphragm is in place.

Do you happen to know which number on the diagram the Orings you are referring to are?....i just wanna make sure i get the right ones, im not really sure which diaphragm you are referring to.
 

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Just curious how far the carbs were out when you synched them this last time?
 
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