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Discussion Starter · #1 ·
From day 1 to now.
Had to do something about all the ugly first before I'd be caught dead riding it around. Did swingarm from a bandit before I took a picture. Went through and cleaned the carbs put it all back together. I can barely get it to run longer than 10 second's and very stubborn to start. Any help or ideas would be appreciated. First time messing with carbs, always had fi bikes.
 

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Hi, I think you have answered your own question mate, if its your first time messing with carbs that's probably where your problem lies, you need to get them off, strip & clean then set them up properly & I would suggest getting some help from someone local with a bit of experience

We will help here as much as possible but its difficult to do without having hands on
 

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its also from chopping the exhaust, not sure what size of kat you have but it look like that was a full Yoshi exhaust pic 1 (the 4 to 1 header and pipe) so if the carbs weren't jetted for that and then you cut it down like the 2nd pic that would piss off the carbs a bit. also not sure if its just my bike but looking at your fuel lines mine is gravity fed (no fuel pumps) so the way those lines dip past the carbs and back up to them might give you some fuel starvation.
Anyone feel free to correct me if im wrong on either of those.
 
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its also from chopping the exhaust, not sure what size of kat you have but it look like that was a full Yoshi exhaust pic 1 (the 4 to 1 header and pipe) so if the carbs weren't jetted for that and then you cut it down like the 2nd pic that would piss off the carbs a bit. also not sure if its just my bike but looking at your fuel lines mine is gravity fed (no fuel pumps) so the way those lines dip past the carbs and back up to them might give you some fuel starvation.
Anyone feel free to correct me if im wrong on either of those.
The exhaust should not stop it running but its going to make it weak & probably burn valves unless its jetted to suit & its going to make the carbs a pig to setup as there will be no scavenge effect from the exhaust gas

Good point on the fuel lines if there is a kink or a stupid inline filter that can cause fuel starvation but I think the fuel line is not on the tap in the first pic
 

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Discussion Starter · #5 ·
Thanks for all the input. I removed the gey inline filters and shortened the lines . I actually have a cutoff on it with baffling inside plus a baffling insert that a lot of the bobber guys use. I actually find it almost as quiet as the yoshi. I followed a real detailed step by step with the carbs and did gaskets on each one.
I probably should note that when I got the bike the idiot before me left it in prime and there was a bad float causing gas to leak into the motor. I think when I drained the oil it was something like 8 quarts of fluid. The damn guy didn't get the hint that all that gas he was putting in was going somwhere.
guess I'll post some progress pics

p.s. forgive my cleanliness. My living quarters/garage got a bit neglected during this time of obsession.
 

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The petcock is in good condition and doesn't leak. Seems like it's starving for fuel yet floods.
Ok there are 2 things it could be .... well these are the easy ones lol

Do you have the plug leads on the right plugs, as you are sat on the bike the left coil feeds #1&4 the right coil #2&3

Is the wiring to the coils on the right way round, orange is + for both the other two (cant remember colours) are - coils are marked +& - on the body near the terminals

Next & most likely as I said before your carbs are still wrong or dirty, float heights out, blocked jets or a load of other stuff the list goes on...... don't worry even people who are supposed to know their stuff get it wrong a hell of a lot of the time & I seem to spend half my life putting them right :)

Once you have checked the other stuff above shout up & I will be happy to walk you through it on the carbs once you have them in your hand
 

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I'd also add check the vac feed line for the petcock, make sure it's not cracked or anything.

but yeah, do the shit he listed already. it's always carbs on boilers. Always, lol.
 

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Discussion Starter · #10 ·
Ok, so started to doubt myself about the carbs so I had a guy come over yesterday and he went through and redid My carbs. He cleaned them in what he called an ultrasound machine. Said I didn't do a bad job but no I could get them as clean as him. He was right. So yet another problem popped up. It will not idle!
So I backed the idle screw out completely, checked for vaccum leaks like everywhere, triple checked the butterflys and disconnected the throttle cable(heard it can bind or something).
What it's doing now is when I start it it'll sound good then jump to about 6k rpms. If I choke it then it might go back down to about 2.5k then jump right back up. I changed my plugs and checked all my wires because i heard that could be a issue. Kinda stumped here.
 

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Oiler Boilereerer...er(s)
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Ok, so started to doubt myself about the carbs so I had a guy come over yesterday and he went through and redid My carbs. He cleaned them in what he called an ultrasound machine. Said I didn't do a bad job but no I could get them as clean as him. He was right. So yet another problem popped up. It will not idle!
So I backed the idle screw out completely, checked for vaccum leaks like everywhere, triple checked the butterflys and disconnected the throttle cable(heard it can bind or something).
What it's doing now is when I start it it'll sound good then jump to about 6k rpms. If I choke it then it might go back down to about 2.5k then jump right back up. I changed my plugs and checked all my wires because i heard that could be a issue. Kinda stumped here.
I actually had a similar problem with my Kat when I first got it. Drove me nuts until I noticed that the throttle cable was routed a little wonky, and was binding, and literally just holding partially open.

A place people usually forget to check for vac leaks is the boots that attach to the engine holding the carbs. They get brittle when they are old, and can get hairline fractures, especially around the screw holes. Also there are oringy gaskets that seal them to the block. I would carefully check the boots and install new seals (cause they are probably original to be honest)
 
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First question..... are you running the stock airbox at the moment ?
Second question .... which carbs do you have 31 32 or 33mm ?
Third question....... have the carbs been bench synced before installing them

Keep with me on this & we will get there ... my first guess it that the sync is way out & the choke is dropping the revs by flooding the engine ..... not much of a problem to be honest
 

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Oiler Boilereerer...er(s)
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First question..... are you running the stock airbox at the moment ?
Second question .... which carbs do you have 31 32 or 33mm ?
Third question....... have the carbs been bench synced before installing them

Keep with me on this & we will get there ... my first guess it that the sync is way out & the choke is dropping the revs by flooding the engine ..... not much of a problem to be honest
Good call. I actually made the assumption that the carb guy would also vac synch, and also that the stock box was on.
 

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Discussion Starter · #14 ·
alright, so the boots look brand new and I used starter fluid to see if it would make a change In rpms, It didnt. Factory airbox. Hmmm, he bench synchronized them but not vac. I'm pretty sure I'm running 32mm. I'll check when I get home. The needles and everything were factory when taken apart to add. I know routing could be an issue, the cable looks new to me.
 
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if you do have 32's that's a bonus, much easier to set up :)

I when you look down the back of the carbs there should be virtually no gap under the butterfly's I use a very thin feeler gauge under them to bench sync my guess is that you will see an obvious gap which is why the revs are picking up

let us know what you find
 

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Discussion Starter · #16 ·
Alright thank you for your input, so I pulled the carbs off again and turns out from the rear the butterfly's are open just enough to stick a very small paperclip through. noob question time,, how do I go about adjusting them. Note that it's not the cable(disconnected it) thanks again!
 
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No worries we are here to help if we can :) getting a paper clip under them is way too much, just check the idle adjuster isn't holding them open before starting what is below

Between carb 1 & 2 you will see an adjuster screw with a small spring on it that one when turned will move the butterflies on those 2 carbs 1 up & 1 down what you are looking for is the same gap under both as low (closed) as you can get ....... I use just the very tip of a feeler gauge to check

The second step is the same as above but with the adjuster between carbs 3 & 4 but the gap may be bigger or smaller than the previous pair at this stage

Last is the adjuster between carbs 2 & 3 this one balances the 2 pairs that you have already set so the gap in all 4 is the same or even completely but lightly closed

You may need to have the idle adjuster lightly seated to get a gap but you can turn it down later before installing

That's a bench sync which should get you running reasonably but they will probably need vac syncing at a later date

I hope that was clear enough but if not shout up
 

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Discussion Starter · #18 ·
No worries we are here to help if we can :) getting a paper clip under them is way too much, just check the idle adjuster isn't holding them open before starting what is below

Between carb 1 & 2 you will see an adjuster screw with a small spring on it that one when turned will move the butterflies on those 2 carbs 1 up & 1 down what you are looking for is the same gap under both as low (closed) as you can get ....... I use just the very tip of a feeler gauge to check

The second step is the same as above but with the adjuster between carbs 3 & 4 but the gap may be bigger or smaller than the previous pair at this stage

Last is the adjuster between carbs 2 & 3 this one balances the 2 pairs that you have already set so the gap in all 4 is the same or even completely but lightly closed

You may need to have the idle adjuster lightly seated to get a gap but you can turn it down later before installing

That's a bench sync which should get you running reasonably but they will probably need vac syncing at a later date

I hope that was clear enough but if not shout up
Sorry to quote it all, but that helped it a lot but I still can't seem to get 2&3 closed all the way. I can get 1&4 but no matter how I adjust them they won't close. That's with the idle adjustment screw backed out all the way as well. If I screw the idle sure in I'd never be able to get it closed backed out so I figured I'd start there... unless I'm doing something wrong. Hmm
 

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Discussion Starter · #19 ·
Another thing I should add is that the tightest I can get 2&3 is enough to stick a standard flat head tip Between. If I try and close them by backing out said screw oon either side 1&4 will open up but 2&3 won't budge if any.
 
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