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Discussion Starter #1
Have a few questions about jetting kits and carb setup. I know its a long post but i need some real help:idunno:. Thanks! :thumb:

1. Just recieved my "dynojet" jet kit, these jets are quite smaller than the stock keihin jets. This is normal?....and i have a question on the decel plugs. What would happen if i didnt plug them? Also, which side has to be plugged? Its either plug the air assembly side, or the metal fitting side.(or just plug the line and connect it back to the carb.

2. Im hoping i dont have to disassemble the entire carb assembly to plug these lines. I also recieved this metal cylinder with an opening on one end, which im wondering what it does? This is a weird shape and looks dented on the open end.

3. Why dont jet kits come with new pilot jets? Are stock keihin pilots supposed to be compatible with dynojet main jets?

4. The dynojet instructions say to basically bypass the PAIR sol. valve. Has anyone done this? Why would it want you to bypass the PAIR valve so my high speed float bowl vent is directly connected?
 

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Have a few questions about jetting kits and carb setup. I know its a long post but i need some real help:idunno:. Thanks! :thumb:

1. Just recieved my "dynojet" jet kit, these jets are quite smaller than the stock keihin jets. This is normal?....and i have a question on the decel plugs. What would happen if i didnt plug them? Also, which side has to be plugged? Its either plug the air assembly side, or the metal fitting side.(or just plug the line and connect it back to the carb.

2. Im hoping i dont have to disassemble the entire carb assembly to plug these lines. I also recieved this metal cylinder with an opening on one end, which im wondering what it does? This is a weird shape and looks dented on the open end.

3. Why dont jet kits come with new pilot jets? Are stock keihin pilots supposed to be compatible with dynojet main jets?

4. The dynojet instructions say to basically bypass the PAIR sol. valve. Has anyone done this? Why would it want you to bypass the PAIR valve so my high speed float bowl vent is directly connected?

Are they smaller or just numbered differently?
What are decel plugs?
Sounds like the tool for the mixture screws?
Because unless you have major engine modifications the pilots should be fine.
The PAIR solenoid has nothing to do with carburetion. What do you mean about the bowl vents?
 

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Discussion Starter #3 (Edited)
Numbered similarly(still 136-142), just sized very differently. i can always take pics if necessary. Decel plugs are deceleration plugs. I asked someone i knew about there being deceleration lines and the guy "looked" like he knew what i was talking about... And i do believe its the mixture screw, it just looks either dented, or....im not sure. Here is the quote from the insert(DI1757) that came with the dynojet kit. After thinking about it, the phrase "road racing" probably matters...as im not road racing it, just riding it.

"6. Locate the fuel mixture tab (Fig. E). Using the tool supplied (DT009), carefully turn the tabs clockwise until they lightly seat and then back out 1/2 turn. NOTE: If you experience a stumble accelerating after hard deceleration from high speed when racing, it is not uncommon to turn the mixture screws all
the way in. Follow instructions on insert DI1757 when using motorcycle for road race appications


Looks like someone tried it here...but that completely bypassed the PAIR sol. I dont see why thats necessary

http://cbrforum.com/forum/cbr-600f3-17/f3-dynojet-jet-kit-vent-tubes-problem-help-120540/
 

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if you need a carb kit i have a brand new one for the 95-98 F3 brand new in the box. its a factory pro kit. sell it to you cheap :thumb:
 

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I just need some answers. I believe the tool is supposed to be D-shaped.

What answers do you still need?
I would remove the PAIR system anyway, regardless of the jetting.
 

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Why would you remove the PAIR system? What benefit would come of removing it?

Because it has no useful purpose and has to be disabled if you want to tune via air/fuel measurement anyway.
 

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Discussion Starter #9
Instead of asking numerous questions that have been answered, i familiarized myself with your search function. Found lots of info, but it seems most of these write ups are for 2001+ bikes. I havent come across a good write up for my cbr f3. It doesnt seem like the parts on a 98 and the parts on the 01+ bikes are the same? maybe i just need to compare it better. Im new to the bike world and trying to get some things accomplished before the riding season is in full swing. I was planning on replacing a bunch of the little black box vent filters that run to the PAIR sol. behind/underneath my air box. But this seems counter-productive if im going to remove/disable the system. Itll save me a good bit of money to NOT replace them, as the parts are coming from honda.
 

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Instead of asking numerous questions that have answer, i familiarized myself with your search function. Found lost of info, but it seems most of these write ups are for 2001+ bikes. I havent come across a good write up for my cbr f3. It doesnt seem like the parts on a 98 and the parts on the 01+ bikes are the same? maybe i just need to compare it better. Im new to the bike world and trying to get some things accomplished before the riding season is in full swing. I was planning on replacing a bunch of the little black box vent filters that run to the PAIR sol. behind/underneath my air box. But this seems counter-productive if im going to remove/disable the system.

The F3 is closer to the F1 and F2 than it is to the F4/F4i - but there's not a lot that is interchangeable. I think even early '95/'96 F3's have some differences to the later '98/'99 models.
 

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Discussion Starter #11
I really dont see much in common with an f4i. Thats why i didnt get very far with the write-ups. The later f3's definitely had some changes to them, as opposed to the earlier 95-96 models. You are correct in that. Seems like there really isnt that much to the PAIR sol. I dont see how it could be super difficult. There are only 2 vents that lead into the pair, that connect to the airbox.

Dynojet recommends bypassing the pair by disconnecting the left hose(DAI line?) from the valve, and connecting it right to the bottom of the airbox hose using a plastic fitting. This completely bypasses the PAIR sol. and then just unplug the connection.

Will the bike recognize the PAIR is removed? Also, I wont have a dyno to adjust my air/fuel afterwards, is this necessary? Thanks blade racer. Your really helping me out brother.

Im going to take a picture to show what it looks like
 

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I really dont see much in common with an f4i. Thats why i didnt get very far with the write-ups. The later f3's definitely had some changes to them, as opposed to the earlier 95-96 models. You are correct in that. Seems like there really isnt that much to the PAIR sol. I dont see how it could be super difficult. There are only 2 vents that lead into the pair, that connect to the airbox.

Dynojet recommends bypassing the pair by disconnecting the left hose(DAI line?) from the valve, and connecting it right to the bottom of the airbox hose using a plastic fitting. This completely bypasses the PAIR sol. and then just unplug the connection.

Will the bike recognize the PAIR is removed? Also, I wont have a dyno to adjust my air/fuel afterwards, is this necessary? Thanks blade racer. Your really helping me out brother.

Im going to take a picture to show what it looks like

The PAIR system has nothing at all to do with the carburetion. The engine doesn't care if it's there or not.
 

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Discussion Starter #13
Well not necessarily the engine, but the machine in general. I know sometimes the factory puts in stupid safety components, which will cause a machine to not run correctly if certain things are unplugged. I phrased that incorrectly. Its not the DAI line. Your completely right though... I keep thinking its part of the carb system and its not. Just getting overwhelmed. Tooks some pics of the rerouting of the hoses. I dont see where there is any need for block off plates. Hows this looking as far as accuracy? .....stay with me on this blade...The fuzziness is clearing...

PAIR as it sits...


Left side hose...


Hoses reconnected...

 

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I really dont see much in common with an f4i...
Just FYI, Enjaye, the "i" in F4i, is for injection, as in fuel injection, so definitely don't look for any comparisons there.
I've never owned an F3 - the only "F" series CBR 600 I've had is an F2, and there might be differences that I'm not familiar with.
It is common, on a lot of kits, to have one larger main jet set, and an assortment of smaller sizes, since, believe it or not, you'll get more power on a STOCK bike, by leaning out the top end.
I think others have gotten most of your questions answered.
For what it's worht, I've always only used Factory Pro Kits, which don't require any plugging and drilling of slides and the like.
 

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Discussion Starter #15
Thanks JNS. Yes the "i" is for injection. Im not a total n00b when it comes to bikes, just new to the bike world. Frankly, i dont know how the f4i model was even brought into discussion. Regardless, im not 100% sure why dynojet recommends drilling out the slides larger than what they are. Ill have to contact them. As far as the decel plugs go, i guess im the only one with this problem, as i dont see anyone else either using them, or asking questions about them. I dont know if they are completely necessary. Im planning on running either a set of 138/140, or 140/142 jets. The bike will only have a slip-on can. Id like to run a BMC air filter but just dont know if the 70 bucks is worth it. KEEP THE THREAD ALIIIVE!!
 

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Now granted, the F2 and F3 are a little different, but I'm guessing those size jets will be a bit rich with a stock air filter, being that you will usually have more gains by leaning out the top-end, with a stock airbox/filter setup (this is why your kit jets are so much smaller).
Truth is, I'm probably wasting your time posting a reply, since I have never carb-tuned an F3! It shouldn't be that much different though.
Are the jet sizes you pulled from the carbs, the ones that are 136-142? Maybe someone can chime in and confirm what the original main jets are sized at...
At any rate, I should leave it to the F3 experts, being that the only HONDA carbureted bikes I've tuned, have been F2's and my other fueling related race-tuning is with my laptop and a 2009 R1 :D...which is soooooo much sweeter, not having to pull the carbs off all the f'n time!!
 

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Discussion Starter #17
Ive got the jet sizes primarily figured out...i think. This originally started by just trying to stop the ever so popular "popping" upon hard deceleration. Im hoping removing the PAIR valve will stop this, but now i have parts i probably didnt need(like jets). So i figured i would instead upgrade to fit the jets, instead of adding upgrades and jetting to suit. I wasnt looking in the right places for answers on the popping, so i started tearing things apart looking to just fix the issue. It has since turned into a project. Both mechanically and cosmetically.
 

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Discussion Starter #18
Ive read that there are actually downfalls to adding a K&N air filter, as they dont breathe quite as well as stock. Has anyone had any luck with anything else aftermarket like a BMC?
 

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The thing is, K&N and BMC filters will breath a lot more than paper, and you will find a lot of people swearing by paper filters only, saying that you will lose power with the aforementioned - but, you will also find a lot of people who have found power gains with "hi-flow" filters, after taking the painstaking time to properly tune all three fueling circuits (mains first, then needle jets, then pilot) to suit the increased flow - I am of the latter group - I do what works, and ignore the naysayers.
Basically, the downfall of these filters is that you cannot just install them, and have an improvement - it takes a lot of work to get it just right, and there are no "magic settings" that will apply to all carbs - it takes work.
Also, care must be taken to maintain those type of filters, with regular cleaning and oiling, if you go that route.
 

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Thanks JNS. Yes the "i" is for injection. Im not a total n00b when it comes to bikes, just new to the bike world. Frankly, i dont know how the f4i model was even brought into discussion. Regardless, im not 100% sure why dynojet recommends drilling out the slides larger than what they are. Ill have to contact them. As far as the decel plugs go, i guess im the only one with this problem, as i dont see anyone else either using them, or asking questions about them. I dont know if they are completely necessary. Im planning on running either a set of 138/140, or 140/142 jets. The bike will only have a slip-on can. Id like to run a BMC air filter but just dont know if the 70 bucks is worth it. KEEP THE THREAD ALIIIVE!!

You brought the F4i into the discussion yourself - "It doesnt seem like the parts on a 98 and the parts on the 01+ bikes are the same?".
Stick with the OEM filters.
 
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