Jetting Reccomendation

Post Reply
windswept6
Forum Regular
Forum Regular
Posts: 29
Joined: Fri Mar 06, 2015 7:03 pm
Location: Central Ohio
Location: In them thar hills- somewhere between Enon, Yellow Springs,and Springfield

Jetting Reccomendation

Post by windswept6 »

I am having the carburetor set on my '82 professionally rebuilt, tuned, and synchronized

I will be running stock '82 header/exhaust pipes ( with crossover) connected to a modern aftermarket muffler set. I plan to connect them with a stainless mid-pipe under the heat shields. I am also considering the K&N type "pod" air filters.

With a stock motor- with pod filters and performance exhaust canisters- what can I expect to tell the mechanic as far as jetting? I want to give him a fighting chance to get things right.

(Note: While the carbs are away, I will be adjusting the valves, checking the cam chain tension, setting the timing, and replacing the plugs/wires and resistor caps - possibly even new Dyna coils)

Thanks

User avatar
Jeff Bennetts
Posting God
Posting God
Posts: 2408
Joined: Wed Mar 05, 2003 8:38 am
Location: Ohio, USA
Location: Ohio, USA

Re: Jetting Reccomendation

Post by Jeff Bennetts »

Is this 82 going to be a stocker in all other respects? If the answer is yes skip the K&N pods and drop in and go with a standard air filter. If you don't mind removing the carbs a couple times to dail everything in then try the pods or drop in K&N's.

Do a search it's all here in the forum, there is a lot of good information in the threads if you do decide to rejet and it will help understand how the jetting effects the performance of the bike.

Maybe Dave or someone will come by and give you a place to start if you decide to use the K&N's but it's still a good idea to do a search and get a feel for how the carbs work.

Mouse
ICOA Member
ICOA Member
Posts: 569
Joined: Fri Jun 12, 2015 9:56 am
Location: Canmore Alberta Canada
Location: Canmore Alberta Canada

Re: Jetting Reccomendation

Post by Mouse »

Just talked about this with Mike Nixon -cbxcarbs.com- K&N pods are not your best choice for performance with a stock motor.
Canadian Amateur Radio Call sign VE6 VES

daves79x
ICOA Technical Director
ICOA Technical Director
Posts: 4736
Joined: Sun Oct 01, 2006 8:05 am
Location: Knox, PA
Location: Knox, PA

Re: Jetting Reccomendation

Post by daves79x »

I'll just echo Jeff's advice - forget the pods and please read the volumes written here as to why. Also hope your mechanic has done CBX carbs before. If he has, he would know this.

Dave

Lerouxseegers
New Member & Happy To Be Here
New Member & Happy To Be Here
Posts: 6
Joined: Sat Feb 27, 2016 9:30 am
Location: Johannesburg
Location: Johannesburg

Re: Jetting Reccomendation

Post by Lerouxseegers »

Please post some pics of the exhaust pipes as I need to make a plan with mine aswell

windswept6
Forum Regular
Forum Regular
Posts: 29
Joined: Fri Mar 06, 2015 7:03 pm
Location: Central Ohio
Location: In them thar hills- somewhere between Enon, Yellow Springs,and Springfield

Re: Jetting Reccomendation

Post by windswept6 »

Thanks guys. I had a feeling that the pods weren't a great idea from what little poking around I had done. I will do some further research.

My only worry is that with stock airbox and jetting- but increased flow in the exhaust that I could end up with a lean condition ( I have read that these motors are prone to burning valves- possibly that's why they were tuned to run rich from factory??)

windswept6
Forum Regular
Forum Regular
Posts: 29
Joined: Fri Mar 06, 2015 7:03 pm
Location: Central Ohio
Location: In them thar hills- somewhere between Enon, Yellow Springs,and Springfield

Re: Jetting Reccomendation

Post by windswept6 »

Lerouxseegers wrote:Please post some pics of the exhaust pipes as I need to make a plan with mine aswell
Will do- the exhaust is next after I get the motor back into the chassis

windswept6
Forum Regular
Forum Regular
Posts: 29
Joined: Fri Mar 06, 2015 7:03 pm
Location: Central Ohio
Location: In them thar hills- somewhere between Enon, Yellow Springs,and Springfield

Re: Jetting Reccomendation

Post by windswept6 »

daves79x wrote:I'll just echo Jeff's advice - forget the pods and please read the volumes written here as to why. Also hope your mechanic has done CBX carbs before. If he has, he would know this.

Dave
Dave, not sure if he has done CBX carbs before. He is an expert with vintage Japanese MC. I supplied him with a rebuild kit from Randakk's and Mike Nixon's carb rebuild manual. Is there anything else that he really needs to know?

daves79x
ICOA Technical Director
ICOA Technical Director
Posts: 4736
Joined: Sun Oct 01, 2006 8:05 am
Location: Knox, PA
Location: Knox, PA

Re: Jetting Reccomendation

Post by daves79x »

Well, there's a bunch of little things particular to CBX carbs that are helpful to know. But a competent mechanic can do it 'by the book' and get them OK.

Your exhaust choice will have little, if any effect on jetting. Intake changes are an entirely different matter. You might have your mechanic shim the needles .020 with a washer, but you need to know that there is a bit more than just installing the washer. This will richen up the low and mid-range. The top end is quite rich enough with the stock 105 mains.

CBXs are not 'prone to burning valves'. Never checking valve clearance is how most valves get burned. With normal, correct maintenance, these entire engines can go 100,000 miles with no major work. Skip the maintenance and you can ruin one in 10,000 miles - just like many other bikes.

Dave

windswept6
Forum Regular
Forum Regular
Posts: 29
Joined: Fri Mar 06, 2015 7:03 pm
Location: Central Ohio
Location: In them thar hills- somewhere between Enon, Yellow Springs,and Springfield

Re: Jetting Reccomendation

Post by windswept6 »

daves79x wrote:Well, there's a bunch of little things particular to CBX carbs that are helpful to know. But a competent mechanic can do it 'by the book' and get them OK.

Your exhaust choice will have little, if any effect on jetting. Intake changes are an entirely different matter. You might have your mechanic shim the needles .020 with a washer, but you need to know that there is a bit more than just installing the washer. This will richen up the low and mid-range. The top end is quite rich enough with the stock 105 mains.

CBXs are not 'prone to burning valves'. Never checking valve clearance is how most valves get burned. With normal, correct maintenance, these entire engines can go 100,000 miles with no major work. Skip the maintenance and you can ruin one in 10,000 miles - just like many other bikes.

Dave
Thanks Dave

Post Reply

Return to “CARBS: Cleaning, Rebuilding, Swaps, Aftermarket, Tuning, Syncing, and More”