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Discussion Starter · #1 ·
Installing the 95" kit with Andrews 37G's. Have the HD SE 2 into 1 Pro pipe and will run the Ness Super Suckler with K&N filter.

While the carb is off the bike...:huh:

My question is: What new "starting" mods should I make to the CV40 I'm running now? It's been Dynojetted and had the slide installed, needle is in position #4, slow is a 48 and the fast jet is a 200. Looking for a baseline. I know I have to raise the needle at least 1 more position already as the bike sorta got flat in the mid-range @ 88in..

Thoughts and suggestions from the "tried and proven" appreciated...

Thanks,

DLR
 

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I think you are going the wrong way. with 48 slow and 200 main you sound rich. I would lower the needle because flat can mean rich. I have a perfect afr 2:1 supertrapp, 95 inch stock heads and tw21 cam with a 190 main.
 

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Discussion Starter · #3 ·
MTClassic,

Understand the logic. Just followed the Dynojet instructions. They called for needle in pos. #5 and I leaned it out a little by putting it in pos. #4, (not as much needle lift). Jetting was supposed to be 190, but I felt with my mods, (per their instructions), 195 would be just right. Couldn't find one so in went the 200. Performance is excellent. Other than wanting to raise the needle up to #5 with the 88 to richen up the mid, I feel like I'm pretty close. Bike has gone 116 mph in this configuration. (Pipe burns a nice light choc. brown, and plugs read perfect.)

Think the AFR must be close, right now. Want to make sure I'm close to right for the 95" /Andrews 37's. Thinking I may have to richen up the low and mid-range, 50 jet and raise the needle? I'm also going to advance the cams 2*.

Thanx..
DLR
 

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DLRVelocity1 said:
MTClassic,

Understand the logic. Just followed the Dynojet instructions. They called for needle in pos. #5 and I leaned it out a little by putting it in pos. #4, (not as much needle lift). Jetting was supposed to be 190, but I felt with my mods, (per their instructions), 195 would be just right. Couldn't find one so in went the 200. Performance is excellent. Other than wanting to raise the needle up to #5 with the 88 to richen up the mid, I feel like I'm pretty close. Bike has gone 116 mph in this configuration. (Pipe burns a nice light choc. brown, and plugs read perfect.)

Think the AFR must be close, right now. Want to make sure I'm close to right for the 95" /Andrews 37's. Thinking I may have to richen up the low and mid-range, 50 jet and raise the needle? I'm also going to advance the cams 2*.

Thanx..
DLR
If you love to do the carb tuning yourself, you can do what I did. I put an O2 sensor in the front pipe and bought a RB racing AFR gage. No data logging capability, but it tells you very precisely where you're at with your AFR. Easy to use, lot's of fun for the money (about $250). Coincidently, it's about as much as you pay for a dyno tune.......
 

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Discussion Starter · #5 ·
Hog,

Greetings to you in Austria! O2 sounds like a great idea! Maybe with a plug that you I could fill the O2 bung with when not using it for AFR? Here in the US, O2's are coming stock on bikes and most of us aren't crazy about them.

You did inspire an idea though. A good friend has a garage and an emissions test station, capable of reading exhaust mixture, i.e. AFR...Will get me close baseline carb tune, but AFR under load is obviously different.

Thanks for the idea! Ride safe.

DLR
 

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DLR,

I permantly installed the RB-racing gage on the bike, it's fun to watch and very cool in the dark. It has an additional signal input for events like shift limiter etc. with a very bright diode. Daytona Twin Tec sells the bung for about $18, which is a lot but it's a hard to come by item (thread is I believe M18* 1.5mm).
It helped my to optimize AFR in cruising range as well as understanding transient responses of the carb e.g. accelrator pump, slide reaction etc. Cool toy.
 

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those bungs are also availible at some auto parts store. Maybe not advance,autozone, or pepboys, but the wholesale end of it... I know that maremont, and flangeman also make them....They are also very common in midas type of exhaust shops. When they make pipes, these are often needed in newer cars.....just trying to help out. i know i have bout them before for like 3-5 bucks.....the maremont p/n was 26503 i think.....
 

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Discussion Starter · #8 ·
Back to the original question....Are there some "Baseline" carb settings I should make during the 95" install? I'm running SBC's heads, 9.8:1 comp, Andrews 37G's, SE 2 into 1, and a Super Sucker style aircleaner. Seems like we got stuck on O2 sensors...:whistle:

DLR
 
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