Jet help

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slickvic

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hey guys. i purchased a 03 fz1. it has 18k on it.

the previous owner installed a full titanium force exhust and he stated he also install stage 1 ivan jet kit.

now, im brand new to the bike world and i haven't dealt with too much carburetors and i have no idea what im getting into.

the issue is the start of the bike.

on full choke, the bike does not start, i need to open the throttle a little bit to get it to ignite.

i have a friend well into the bike world and he stated that it is running lean.

the bike seems to back fire alot when letting go of the gas.

i dont have tremendous experience on bikes so i do not have anything to compare it much.

could anybody steer me in the right direction??

thanks:sport12:
 
Congrats on the new bike! If the bike has been sitting for any amount of time over a few weeks, it's very likely that the idle jets are gummed up. It's very common on the GenI FZ1s (01-05). Being that you have a full exhaust, you no longer have the EXUP Valve. The exhaust probably sounds a bit louder than just having a slip-on with the stock exhaust headers and EXUP. The back firing may be that you still have the AIS System in place. It's an air injection system that sits atop the engine cylinder head. You can either leave it if the backfiring doesn't bother you, or remove it and "cap" the openings to get rid of most of the backfiring. Just remember that the gummed up carbs may contribute to it running like that as well. I'd go and first get some Seafoam and run it through first. Many times thats all it takes to clean up the carbs. DO NOT run the bike with the choke ON for any extended period of time as it's not good for the cylinder walls. South Florida should be hot enough that you should only need about a 1/2 minute or less on choke. If it's not running unless it's on choke, then surely the carbs are gummed up. If thats the only issue, you should be happy cause it's an easy fix. Go to any auto parts store and ask for a can of Seafoam. It's usually 1oz. per gallon, but when things are gummed up you might as well do maybe 1-1/2oz per gallon of gas. Put it in your tank, start her up and let her run for a while. Maybe a nice slow neighborhood run to let it work through the carbs. You'll be amazed at how good it cleans up gunk. Let us know what happens, and please post some pics of the new ride! Maybe a small video clip of you starting her up so we can get a better idea of what might be happening.
 
hey riderNY thanks for the tips

heres the vid

sorry i ended up putting the cam down and you see nothing for a couple seconds

[ame=http://www.youtube.com/watch?v=Nas6tiL7tRU]Fz1 - YouTube[/ame]

as i could not hold the cam and turn it on

what i did was i attempted to cold start it with the choke fully on and it didnt want to start.

after i gave it very little fuel it turned on with out a problems.

i wanted to point out just it case it helps is that once the bike has started i can turn it off and turn it back on without any choke nor throttle (im sure thats common but not sure about how carbs fully work)

do you think the seafoam will fix this issue? or is it a jet related issue?
 
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Check to make sure it ACTUALLY has been jetted. There should be some screw thing drilled out, i'm not sure which one. I would think its obvious though.
 
Many people remove/drill the cover from the pilot jet and assume it's impact is over the entire range. The pilot jet is only for start up, The needle lift/taper and main jet impact the mid-range to WFO.

[ame=http://www.youtube.com/watch?v=uMAKyTvjqaQ]How a Motorcycle Carburetor Works - YouTube[/ame]
 
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I listened to the video and it certainly looks like your idles jets may be dirty. You still have the A.I.S. System installed which explains a lot of the backfiring. I'd say based on the way it sounded, that a tank or two using the Seafoam may clear that up no problem. You didn't mention how she ran above idle when your on the gas? Also, like was said, if you look at the carbs and are able to see the mixture screws, it would indicate that the jets were indeed changed. If they are not visible and still encapsulated, then I doubt they changed them at all. The bike looks nice by the way. Your gonna love it.
 
RE:

Interesting enough..
All of the responses above are dead on. If you still have issues read below.
I had the same issues with my choke after I installed Ivans jet kit last summer. After a lot of minor adjustments I found out that my carbs were out of sync.
When I soaked my carbs and cleaned them I inadvertently unscrewed the individual idle adjustment screws out of alignment. Upon installation the choke would not work, it would stumble and the carbs would flood after parking.
After re-syncing the carbs all of the problems went away and my bike now runs like a bat out of hell!
Hope this helps..
 
Prongomatic said:
Interesting enough..
All of the responses above are dead on. If you still have issues read below.
I had the same issues with my choke after I installed Ivans jet kit last summer. After a lot of minor adjustments I found out that my carbs were out of sync.
When I soaked my carbs and cleaned them I inadvertently unscrewed the individual idle adjustment screws out of alignment. Upon installation the choke would not work, it would stumble and the carbs would flood after parking.
After re-syncing the carbs all of the problems went away and my bike now runs like a bat out of hell!
Hope this helps..
Click to expand...

i attempted to clean the carb with some simple sea foam but it did not do the trick. sorry for the long delay response.

i been reading a bit on carbs, i have a feeling i need to adjust one of 3 jets or all even which are my pilot air jet, mixture screw, or pilot fuel jet. its only a starting issue. i feel like when i open throttle just a micro of a bit im letting enough air in to start it. or maybe the pilot it letting too much fuel and i need to compensate with air but i believe if that was occurring it would start would much higher rpms?

let me kno what you guys think and i was wondering if i need to remove the carbs to adjust those 3 jets. from what i can tell under the carbs there a brass/kinda cover under one...

let me kno guys and thanks!
 
Hi, I'm no carburation expert but I opened up a few and the bikes still ride .

First you should know starting is a known problem with gen1's , it is not the can
I think it's a sum of problems/modifications to make the R1 engine a bit more docile , r1 doesn't have it, but this is another topic.

So , what can you do?

First of all take out the carbs and see if you have the original main jets or any other mod (shorter spring, drilled sliders etc.)

If they are moded I would clean them (by hand) change orings , set/check floats and mix-screws then install and balance and tune TPS ... and hope for the best
It will still start with a bit of throttle but it must run better then before.


If the carbs are stock install a jet kit of choice, (I'm very pleased with Ivan's)

A jet kit will make it much accelerate smoother, less vibrations and gain a bit of power, but the smoothness is worth the money.

From what you said I think you're not confident enough to do any of this, I can tell you it's easier then it looks but takes a bit of patience and research.

I see many good reviews of a timing advancer that should make the bike start better, this mode I didn't install yet
:poke:
 
Where are you in south Florida?
All my bikes are jetted, and they won't full choke start down here...1/4 or 1/2 choke is all that's needed.
If the brass cover is still there, it wasn't jetted, those cover the mixture screws.
 
Your starting issues need not warrant concern, everything seems to be normal from my experience and what I have read in the past. My gen 1 always needs a bit of throttle or choke or combination to start (unless jetted, needle and float adjustment are suppose to help/solve it). When warm, and hasn't been sitting long, my bike will start with just the button.

From what I have read its because the Gen 1 FZ1 has rich starting issues due to flooding bowls and the cylinders becoming wet. Opening the throttle only leans it out by opening the butterfly, hence why it starts easier. That also makes sense because when I first acquired my bike it had clogged pilots and ran lean; yet the bike started up no issues and no choke. :wtf:

From owning 3 carbed bikes in my past everything seems normal. Starting issues have always been the carbs biggest complaint.

One thing that might help would be new plugs, 16K is when they are suppose to be swapped, so depending on if the PO changed the it could make a bit of a difference in starting.
 
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hey guys, i had the privilege to meet up with 85vmax and with his help i was able to learn a lot about the fz1.

from what we could tell we believe that the previous owner has not install a stage one kit alvin on my bike like he stated

the symptoms and start up were concluded that was identical to those of a stock fz1.

with that being said what i think ill do is a stage 3 kit from factory pro. i like the fact that you do not have to drill into the crabs and for a newbie moto guy like me it sounds like its worth the money. the individual air pods does look good too.

has anyone had any problems with them or has anything i should know before doing this install?

maybe recommend any other manufacture carb kit that does NOT require drilling that you guys have found good?

i prob wont being doing the install for a least a month. ill have some time to research and look around (if i can squeeze some time, i hope)


Thank you guys for your time!
 
ddemlong said:
Your starting issues need not warrant concern, everything seems to be normal from my experience and what I have read in the past. My gen 1 always needs a bit of throttle or choke or combination to start (unless jetted, needle and float adjustment are suppose to help/solve it). When warm, and hasn't been sitting long, my bike will start with just the button.

From what I have read its because the Gen 1 FZ1 has rich starting issues due to flooding bowls and the cylinders becoming wet. Opening the throttle only leans it out by opening the butterfly, hence why it starts easier. That also makes sense because when I first acquired my bike it had clogged pilots and ran lean; yet the bike started up no issues and no choke. :wtf:

From owning 3 carbed bikes in my past everything seems normal. Starting issues have always been the carbs biggest complaint.

One thing that might help would be new plugs, 16K is when they are suppose to be swapped, so depending on if the PO changed the it could make a bit of a difference in starting.
Click to expand...

sounds good man thank you ill look into plugs also
 
Nothing wrong with buying a jet kit but you can save yourself some money by getting the individual jets, shimming the needles (with Radio shack washers), adjusting the pilots and resetting the floats. And plus, no drilling required. You need to take the carbs out anyway to clean so why not do a search on the other site for RavenRiders carb mod. I bought my 4 jets from Amazon for $11 delivered. Do the research and you'll find everything you need to know to get more than satisfactory results...

These are the jets I used:

[ame=http://www.amazon.com/gp/product/B000WJ5I8S/ref=oh_details_o00_s00_i00]Mikuni CV Carb Jets (Small Round) Main Jets (KN102.221) Size 127.5 : Amazon.com : Automotive[/ame]
 
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