Thanks guys for the responses. Lots of good info. to chew over.

I pulled the carbs this morning, to give 'em a good cleaning, and to see what size jets were in there.

A few questions that have arisen...

First, one of the screws was stripped by the PO on the top of the carb, covering the diaphragm. I can get everything else out, but not that one. Is it still ok to use carb cleaner on that one. I'm worried that the carb cleaner might eat the diaphragm.

Secondly, the PO managed to break half off of one of the pilot jets. It's still got a good bit sticking out of the carb body, I just can't manage to get it to budge with needlenose plyers. Any ideas? Would an Easy-Out work?

Lastly, the main jet was 102, and pilot was 35. Where's the best place to get these? The local shop didn't have any in stock, and I'd rather order online anyways. Any recommendations?

As well... can anybody point me towards a good starting size for main and pilot jets? One online shop recommended 108 and 38. Again, I'm running an 89 CBR600, naked style, with air holes almost covered, a K&N filter, and Vance and Hines exhaust.

Any help is greatly appreciated!

Charlie

 

1. You are correct. Most carb cleaners will make quick work of the diaphragm. I'd just leave it be, provided the slide moved well.

2. I wouldn't use an easy out for that. You will generate a ton of metal filings, which will find their way into that idle circuit. Try some vicegrips and some very careful force. You can also try cutting a slot into the top of the jet and using a screwdriver to get it out.

3. FSM says 105/35 for the jets. Why use a high flow K&N and then block the air inlets? If you are using a high flow filter, jet accordingly, otherwise, stick with an oem filter. With a highflow filter and aftermarket slipon, you are probably running lean, so bumping it up a bit won't hurt.

Dynojet and Factory pro have jet kits for our bikes.

 

I hate when I open up a carb to find the last guy messed it up. Had a set of Hurricane carbs the PO couldn't find the float bowl gaskets so he used some gasket forming stuff that was like goo...problem was the goo when everywhere in the carbs and didn't stop the bowls from leaking.


You should look at the local hardware for a needle nose vise grips. They work great for getting those stripped phillips heads out and will also work on that jet...smaller grip jaws...they are great for the stuff your dealing with.


I buy all my jets from these guys:


HONDA CBR600F HURRICANE main jet slow air pilot kit


They have jets for every carb I ever had and you'll get them in a few days. Also go to the home page there is all kinds of hard to find stuff there...and good how to info.


In a case like yours where you don't know exactly where you'll need to be on jet size, buy steps of 3 sizes from whatever baseline you choose. As it stands the only thing you know is what size is in there, so go with the next 3 sizes up. I would go for full size increments rather than 1/2 sizes.


There is no one that can tell you the exact size jets you will need. Someone on the board may have a similar set-up and can tell you what they are using, but that does not guarantee the sizes will be right for your bike. This is because your engine and set up might be slightly different, but most importantly the location and altitude make a big difference in jet sizing. You have to tune it and figure it out yourself for your bike.


Good luck.

 

Jet Kit Calculator Techincal - Jet kits for Carburetors

This site recommended 108's and 38's based on my bike's upgrades, elevation, and temperature.

 

Try it. But I would buy sets on either side too just in case.

 

A couple more questions...

I'm going to change out the plugs since I have it all apart, and can't ride it. Anyone know what the factory gap is supposed to be on the NGK's?

And how on earth do you get to the plugs? Has anyone found a combo of extensions that works well? I don't have the factory tool kit.

And does anyone know where I can purchase shims for the carb needle? One site suggested adding two, but I didn't want to purchase their kit, since it was much more cost effective to source the parts myself.

Thanks!

 

Can't answer for sure on your f1. But on my f3, the gap is .8-.9.

I use a regular sparkplug socket, along with a universal then the 2.5" (I think that's what it is), extension. Works well for me. The sparkplug socket is vital. It has that rubber boot inside that holds onto the plug.

I've seen folks just use tiny washers as shims. That's seems to work well.

 

Oh, and the carb was totally gummed up with all sorts of black, gummy crap. I'm thinking that it's probably time to change out the fuel filter... where is it located?

 

And lastly... what is the specific model # of the Keihin pilot jet? I found the main jet, but can't find which Keihin jet to order, and there seem to be several.

Thanks!

 

Not sure where your at but you can get .040" aluminum washers at Home Depot in the washers bin...that's what I use.


Oh, and the carb was totally gummed up with all sorts of black, gummy crap. I'm thinking that it's probably time to change out the fuel filter... where is it located?


That black gummy stuff is not from a dirty fuel filter. It's from fuel sitting in the carb bowl...for a long time. Pretty common. You need to be sure you clean all the passages and take everything out. Don't loose the washer, o-ring and spring on each of the pilot screws. Make sure you clean out the pilot passages.

And lastly... what is the specific model # of the Keihin pilot jet? I found the main jet, but can't find which Keihin jet to order, and there seem to be several.


I gave you the link to JetsRUs in an earlier post. All of the information is there. Go to the home page if you want to find the numbers...otherwise the link page gives you Hurricane specific jets both aftermarket and Keihin.