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Carb Rebuild Kit

spyd3rm4n said:
So far so good, I just have to bolt the float bowls back on and put the top caps back on.

The All Balls kit comes with a ton of o-rings, screws, needles, washers, jets, float needles, and float needle holders. All seem good quality but not everything is marked the same as the original Mikuni parts. For example only the main jets have sizes marked and they're exactly the same as the stock sizes, staggered 130 and 132.5.

I didn't use any of the included jets. The tips of the mixture screws looked thinner than my stock screws so I didn't use them either. The float needles and needles holder are good and I definitely needed those.

Overall it seems like a good kit. If I would have sourced the bowl gaskets, misc o-rings, and float needle assemblies separately I probably would have paid the same ($100). I'm just glad it came with new screws for everything. Most of my existing screws were reusable except the threads on the screws that hold the float bowl pins down got mangled. Good news is the replacement screws fit fine. The real test now is if the bike starts and runs.

I am following the RavenRider jetting, since that worked so well on my Silver bike, sourcing the 127.5 mains and euro needles. The mixture screw plugs were already removed, but the rest of the carb internals had all stock jetting.

I just don't know what size drill bit to use on the slide holes. The original RavenRider write up says to use a "#32 drill bit (2.7mm)" but #32 is actually 2.95mm which is quite a lot bigger than the existing slide holes.
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I am trying to find the RavenRider writeup but can't seem to find it anywhere. If you have it, can you send it over? About to dig into a new to me FZ1 that won't idle. Figured I would rejet it while I was in there.
 
FZ1Colorado said:
I am trying to find the RavenRider writeup but can't seem to find it anywhere. If you have it, can you send it over? About to dig into a new to me FZ1 that won't idle. Figured I would rejet it while I was in there.
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Here you go:

RavenRider's Gen 1 Carb Stuff - FZ1OA Message Board

RavenRider's Gen 1 Carb Stuff Gen 1 Exhausts, Carburetion & Performance
web.archive.org web.archive.org

The photos are gone so you won't see the detailed instructions for the air box holes or the carb boot porting. Any questions about the air box lid modification and I can try to snap a photo of mine next time.

I have a set of Dynojet needles from my 2002 FZ1 if you're interested. I don't know much about that specific kit but I'm guessing they're similar to the stock needles but have several slots for the clip to raise and lower the needle without washers or extra spacers.


As for not idling it's likely a clogged jet. All the idle or running problems I've had on my carbed FZ1s (including this "new" one I recently picked up) were caused by blocked pilot jets. Fuel evaporates slowly from the carbs when the bike sits and leaves junk behind. Since my last carb cleaning on my Silver 02 FZ1 I got in the habit of just turning the key on once a week so the fuel pump can refill the bowls, haven't had any problems since.
 
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FWIW, I tried the needles from a DynoJet FZ1 jet kit in my '03 with Mikuni jets ( non DJ jets ) and it ran like POO. Old tuner that worked for Yamaha for decades explained the taper on the DJ needles is different, even if not visible to the eye. Also the DynoJet numbers for their jets is the hole size, where the Mikuni ( and Yamaha OE jets ) were flow numbers. So a DJ 125 is not the same as a Mikuni or OEM 125.

Link to the Gen 1 airbox mod pic .... https://www.998cc.org/threads/ravenrider-gen-1-carb-stuff-video.8893/
 
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spyd3rm4n said:
Here you go:

RavenRider's Gen 1 Carb Stuff - FZ1OA Message Board

RavenRider's Gen 1 Carb Stuff Gen 1 Exhausts, Carburetion & Performance
web.archive.org web.archive.org

The photos are gone so you won't see the detailed instructions for the air box holes or the carb boot porting. Any questions about the air box lid modification and I can try to snap a photo of mine next time.

I have a set of Dynojet needles from my 2002 FZ1 if you're interested. I don't know much about that specific kit but I'm guessing they're similar to the stock needles but have several slots for the clip to raise and lower the needle without washers or extra spacers.


As for not idling it's likely a clogged jet. All the idle or running problems I've had on my carbed FZ1s (including this "new" one I recently picked up) were caused by blocked pilot jets. Fuel evaporates slowly from the carbs when the bike sits and leaves junk behind. Since my last carb cleaning on my Silver 02 FZ1 I got in the habit of just turning the key on once a week so the fuel pump can refill the bowls, haven't had any problems since.
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Thank you so much! So I pulled the carbs out and I'm not sure the jets in here are original. They have markings that say "factory 148k." Also, the needle has three clip positions on it. The order of which they had them installed it was Needle, spacer, clip, spring, needle keeper that has the o-ring on it. Does that sound correct? Looking at diagrams in the service manual show a washer in there somewhere. Debating if I should order genuine Mikuni jets from jetsrus or see if I can get it running with the jets from the all balls kit. What do you think I should do?
 
FZ1Colorado said:
Thank you so much! So I pulled the carbs out and I'm not sure the jets in here are original. They have markings that say "factory 148k." Also, the needle has three clip positions on it. The order of which they had them installed it was Needle, spacer, clip, spring, needle keeper that has the o-ring on it. Does that sound correct? Looking at diagrams in the service manual show a washer in there somewhere. Debating if I should order genuine Mikuni jets from jetsrus or see if I can get it running with the jets from the all balls kit. What do you think I should do?
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Those don't sound like Mikuni jets or needles. Hopefully some seasoned experts will be able to identify them. Given they're unknown (at least not talked about a billion times over the last 25 years like Ivans, DWs, or RRs) it'll be far easier to just install a jet kit or source the stock needles and shims and genuine jets for the RR jetting recommendations. Those three jetting setups are proven to work well.

The All Balls jets are *probably* fine but my kit didn't include any instructions. They're likely to be the same as stock jet sizes which is one of the key things were trying to change with all these jet kit options (I stored mine away in a garage drawer and I'm too lazy to check!)
 
Isleoman said:
"Factory Pro" was a jet kit back in the day.

Yamaha FZ1

www.factorypro.com
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I love that 1990s-era website, complete with a page visit counter! Haven't seen one of those in ages.

I'm not too familiar with them, I don't remember many people on fz1oa talking about them. Their subtle jabs at the other tuners is a little odd; I usually don't trust sellers that bash competitors like that.
 
Factory Pro probably had more success with other brands/models before getting involved with Gen 1s. They supposedly worked ok. When you do a RavenRider mod yourself you understand there isn't much to "jet kits". Not taking anything away from the tremendous research that Dale and Ivan did, but it is cheap to 90% replicate once the research is done.

What I like about the RavenRider route is I lost no MPG. Still get 50 mpg every fill up in the spring, summer and fall. Goes down to 45 in winter due to winter blend. Is it noticeably faster than stock? Not by me.
 
Isleoman said:
Factory Pro probably had more success with other brands/models before getting involved with Gen 1s. They supposedly worked ok. When you do a RavenRider mod yourself you understand there isn't much to "jet kits". Not taking anything away from the tremendous research that Dale and Ivan did, but it is cheap to 90% replicate once the research is done.

What I like about the RavenRider route is I lost no MPG. Still get 50 mpg every fill up in the spring, summer and fall. Goes down to 45 in winter due to winter blend. Is it noticeably faster than stock? Not by me.
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What riding conditions give you that mileage? I haven't checked my exact mileage, but it's somewhere around 40-45, lots of sit time idling at traffic lights.
 
spyd3rm4n said:
What riding conditions give you that mileage? I haven't checked my exact mileage, but it's somewhere around 40-45, lots of sit time idling at traffic lights.
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Doesn't matter really, although I don't spend much time in stop/go traffic situations......... if I can help it.
 
I ran the Factory Pro stuff in the early R1, CBR900RR and Hawk GT that I raced. Then Dynojet made their marketing push and sort of took over.
I did have a couple guys with FZ1 that never could get their bikes to run with the Factory kit. Replaced it with Dale's kit and both are still is going strong today.

Other than the staggered jet sizes suggested by Dale ( 130 outers and 127.5 inners ) and just 1 drilled hole on the air filter lid, the RR mod is almost the same setup.
Dale also just has folks drill the hole in the center of the lid and not cut the snorkel.
 
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i believe i have the all balls kit, bought it a couple years back. but now trying to do the carbs. the needed jet is different only one location for a clip, old one has like six or seven of them.
none of the new jets are marked as to sizing.
but yes lots of washers and screws.
bowl o-ring is a problem getting it in. little dab of wheel bearing grease works good here.

sad for me one of those little C clips went “poing” when my phone rang. it was nice and quiet and my mind was on the clip. as they sometimes can be a problem.
any source for them?
yes postage will cost more than a dozen clips.
 
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