Carburetor Jet Tuning - Updates on 1st Post

[Chad in Michigan]

More info on tuning CV carbs, whrere I learned a bunch of stuff

http://www.factorypro.com/tech_tuning_procedures/tuning_carbtune,CV,high_rpm_engines.html

More FYI:

The carbs that have VP30A on it are california models,
The carbs that have VP31A are 49 state models

I see that now about the Jet numbers, just took someone smarter than me to point that out. 

I forgot about the possibility of the CA. models. Honda listed only one Slow Jet, a #40, but still moving up one would probably be okay. Than again, taking the stock Slow Jet to the max 3 turns might just be enough.

Lance having to add 3 shims with a stock air filter and V & H pipes leads me to believe we need more if we are running a K & N air filter also. Lance may be a bit overkill at certain throttle positions but I don't know unless one of us rides it for comparisons sake.

The consensuses is so far, the stock Magna is lean and would benefit from at least 1 shim and adjustment of Pilot Screws. Add a K&N and another shim would seem logical, add pipes and another shim might be logical. Along at some point changing Main Jets and possible Needle Jets. The #110  Mains have me curious since that is the only other option Honda shows.

I don't know if Honda dealer would be able to shed some light on the 2 Needle Jets, or verify one is for the CA. model.     

At some point Allen, i would be willing to do some testing, as you mentioned. I like to think it through first to limit the work. Hopefully nail it on the first couple of tries.   

[TLRam1]

Chad

K & N

V & H exhaust

Dyna 3000 Ignition Module w/other mods. 

Pilot Jet #45 – 3 Turns out – runs rich

Shims – 2 additional

Mains #112

Low end is rich

Torquey, super punchy midrange and unstoppable top end.
___________________________________________________________________

Lance

K & N

Stock exhaust

Shims - 2 additional

Pilots screws out 2 3/4 turns

This helped my bike quite a bit, hardly any drop or stumble now at all.


Thanks Lance for your input.
____________________________________________________________________

Gregs thoughts,

K & N

Vance & Hines pipes

Shims - 1-2 additional for a .040"-.060" total raise. Greg's possible ideal raise is .050".

Pilots out 3 ¼ turns


From what I have read and experienced I lean to Greg and Lances experience and thoughts. 


I believe most prefer not to modify as Greg states with the Cobra Jet kit.

My question though, does the Cobra Jet kit correct all issues, will more shims do as well of a job as the Cobra kit (or be pretty close), can you buy a different Needle Jet w/o mods to the carbs?

[TLRam1]

Chad,

Thanks for the info. Great stuff, your speaking our language!!

Everyone that has replied has given good information.. I am guessing Greg and Allen has probably worked on these carbs more than anyone and I think as the replies come in the information helps us form solutions and limits our time and monies on testing.

I would like to clarify and confirm Chad.

Did you try the setup of 105 Mains with 1 or 2 Shims? If so, you are saying you can tell a significant difference between that and what you have now?

When you went to the 110 Mains, how did that work compared to the 105, than to the 112? Were your shims always at 2 additional per Needle?

I take it you are still running stock Needle Jets. correct?

What's your gas mileage?

Have you checked your plug color?

If you can remember elaborate of some of the setups you had and differences.

I wanted to go by Honda today and see if they could elaborate of the 2 Needle Jets but will try next week sometime.

I think we're getting somewhere.......

[Chad in Michigan]

Do me a favor, check out this thread over at Magna Riders Forum - It was detailed step by step what I did, it's a good read.

http://forums.delphiforums.com/MagnaRider/messages?msg=14706.1

Let me know if you have any questions after reading that, maybe I forgot something, it's been awhile.

By the way, I helped a guy yesterday with his carbs. We set his up with k&n, stock pipes with no mods, 3 shims on each needle,105 jets,  2 3/4 turns out. It ran good for him all the way home he told me., and took it out later last night and was good also.  He took it for a short spin around and it didnt have enough time to warm up, and said there was a flat spot aout 5k, but he said it went away after he drive it for a while.

Chad,

Thanks for the info. Great stuff, your speaking our language!!

Everyone that has replied has given good information.. I am guessing Greg and Allen has probably worked on these carbs more than anyone and I think as the replies come in the information helps us form solutions and limits our time and monies on testing.

I would like to clarify and confirm Chad.

Did you try the setup of 105 Mains with 2 or 3 Shims? If so, you are saying you can tell a significant difference between that and what you have now?

When you went to the 110 Mains, how did that work compared to the 105, than to the 112? Were your shims always at 3 per Needle?

I take it you are still running stock Needle Jets. correct?

What's your gas mileage?

Have you checked your plug color?

If you can remember elaborate of some of the setups you had and differences.

I wanted to go by Honda today and see if they could elaborate of the 2 Needle Jets but will try next week sometime.

I think we're getting somewhere.......

[TLRam1]

Chad's friend

K & N

Stock exhaust

Shims – 2 additional

Main Jets - #105

Pilots – 2 ¾ turns

Ran good for him all the way home, Cold, there was a flat spot around 5k, went away after it warmed up

___________________________________________________________________

Chad

K & N

V & H exhaust

Dyna 3000 Ignition Module w/other mods. 

Pilot Jet #45 – 3 Turns out – runs rich

Shims – 2 additional

Mains #112

Low end is rich

Torquey, super punchy midrange and unstoppable top end.
___________________________________________________________________

Lance

K & N

Stock exhaust

Shims - 2 additional

Pilots screws out 2 3/4 turns

This helped my bike quite a bit, hardly any drop or stumble now at all.


Thanks Lance for your input.
____________________________________________________________________

Gregs thoughts,

K & N

Vance & Hines pipes

Shims - 1-2 additional  for a .040"-.060" total raise. Gregs possible ideal raise is .050".

Pilots out 3 ¼ turns


From what I have read and experienced I lean to Greg and Lances experience and thoughts. 


I believe most prefer not to modify as Greg states with the Cobra Jet kit.

My question though, does the Cobra Jet kit correct all issues, will more shims do as well of a job as the Cobra kit (or be pretty close), can you buy a different Needle Jet w/o mods to the carbs?

[TLRam1]

Thanks Chad, I will read your writeup when I have more time and get back to you if questions arise.

I including your friends info in the previous post.

[Chad in Michigan]

Well I tried 2.5 turns on the pilots today.. Too lean.. Lack of power until full warmup today, about 15-20 mins into my ride. Decel popping was present and definately more noticable with my full face helmet on. After complete warm up, it ran better, but still not as good as 3 turns out. I will try 2 3/4 next. I'd rather have it a little rich than lean, but we'll see how 2 3/4 turns does first.

Thanks Chad, I will read your writeup when I have more time and get back to you if questions arise.

I including your friends info in the previous post.

[L J VFR]

I think the pilots need to be at 3 turns or more . My bike would not start without choke before and now it does first thing in the morning with no choke.  The K and N was causing my lean spot at midrange and with the extra shim for a total of 3 it took the lean spot out. Remember, I have bone stock exhaust...  Good luck...   Lance

[lragan]

I bought my Magna in Sept 2006.  It came with stock carbs and filter, but with Cobra pipes.  I noticed the popping on decel, and the illness in mid-range.  Following the write-up in http://www.magnaownersoftexas.com/tips.htm#A1.31 by Greg, installed a K&N Filter and Dave Dodge's DRP-64550.  Backed out 3 turns.  Also resynced with mercury stick. 

Starting dramatically improved. Immediately solved the mid-range issue.  Popping on deceleration gradually disappeared over the next 1000 miles or so.  Mileage dropped from 50 (avg) to 45 (avg). 

Unfortunately, I don't remember how many shims were in the kit, or if I installed them all.  I did not throw them away, and can look in the parts box I keep to see if there are any "left over", if anyone is interested.

[TLRam1]

Lawrence

K & N

Cobra Pipes

Shims – 2 additional

Main Jets - #105

Pilot Screws – 3 turns

Re-synced carbs with mercury stick

Starting improved, solved the mid-range issue.  Popping on deceleration disappeared Mileage dropped from 50 (avg) to 45 (avg).

_____________________________________________________________________

Chad's friend

K & N

Stock exhaust

Shims – 2 additional

Main Jets - #105

Pilots – 2 ¾ turns

Ran good for him all the way home, Cold, there was a flat spot around 5k, went away after it warmed up

___________________________________________________________________

Chad

K & N

V & H exhaust

Dyna 3000 Ignition Module, Dyna coils, Dyna 8mm wires, Pingle fuel petcock, Pingel fuel filter.

Pilot Jet #45 – 3 Turns out – runs rich

Shims – 2 additional

Mains #112

Low end is rich

Torquey, super punchy midrange and unstoppable top end.
___________________________________________________________________

Lance

K & N

Stock exhaust

Shims - 2 additional

Pilots screws out 2 3/4 turns

This helped my bike quite a bit, hardly any drop or stumble now at all.


Thanks Lance for your input.
____________________________________________________________________

Gregs thoughts,

K & N

Vance & Hines pipes

Shims - 1-2 additional for a .040"-.060" total raise. Gregs possible ideal raise is .050".

Pilots out 3 ¼ turns


From what I have read and experienced I lean to Greg and Lances experience and thoughts. 


I believe most prefer not to modify as Greg states with the Cobra Jet kit.

My question though, does the Cobra Jet kit correct all issues, will more shims do as well of a job as the Cobra kit (or be pretty close), can you buy a different Needle Jet w/o mods to the carbs?

[TLRam1]

FYI

This came from the MRF. If this is correct, I was unaware.

The DD jet+shim kit is designed for a bone stock Magna including the exhaust. In fact, it is the factory stock setup for Non-USA Magnas.

Okay Chad I went through all 63 post on MRF. Whoosh!!

Chad, I was coming to the conclusion of trying this with my V & H pipes and K & N.

#110 Mains

2 - Shims additional

#42 - Pilots

2.75 - 3 Turns

The Pingle petcock, wires and Dyna should have little effect if any on these settings.

That being said, I do like to get all I am suppose to out of a motor with out being too rich and don't want to take the carbs off any more than necessary.  How confident are you with being dialed in and not too rich at any throttle opening? I need a real from-the-gut response so I know what direction to lean.

Chad, what's your altitude?

[Greg Cothern]

One would need a exhaust gas analyzer and a Dyno to read all of this to get the perfect setup.  Would take a lot of time pulling, changing, and tuning of all the mentioned parts as well.

[Chad in Michigan]

I am in Michigan, close enough to sea level. With that setup, i think i tried 3.5 on the pilots and it worked good, maybe it was 3, but definately not 2.75. All I know is that every time I changed the setup, it got better. Like I said, I am at 112 mains now, and the top end is perfect. the 110 mains are lacking at the very top but you really wouldnt know it. I figured i'd try the 112's cause i already bought them, and i think it improved for my setup. as soon as i can, i am going to get it dyno'ed. It's definately going to be a huge improvement. I let another guy up here ride my bike for a bit and he says it's a different machine altogether. that was with the 110's, 45's set to 3 turns out and 3 shims. I think the bigger pilots are what makes the flat spots go away on the low end to midrange transition. I'd say go with the 45 pilots, and you can always turn them in if you feel it's too rich. the 40's are way past the 'normal' adjust ment with that combo at 3.25 to 4 turns out. I probably could have turned the 42's out even more, but instead opted for the 45's. Either way, you'll like it, i'm sure. Hope this helps, chad


quote author=TLRam1 link=topic=2119.msg16455#msg16455 date=1212463493]
FYI

This came from the MRF. If this is correct, I was unaware.

The DD jet+shim kit is designed for a bone stock Magna including the exhaust. In fact, it is the factory stock setup for Non-USA Magnas.

Okay Chad I went through all 63 post on MRF. Whoosh!!

Chad, I was coming to the conclusion of trying this with my V & H pipes and K & N.

#110 Mains

3  - Shims

#42 - Pilots

2.75 - 3 Turns

The Pingle petcock, wires and Dyna should have little effect if any on these settings.

That being said, I do like to get all I am suppose to out of a motor with out being too rich and don't want to take the carbs off any more than necessary.  How confident are you with being dialed in and not too rich at any throttle opening? I need a real from-the-gut response so I know what direction to lean.

Chad, what's your altitude?


[/quote]

[TLRam1]

Your saying I need to do this, correct?

#112 Mains

2 - Shims additional

#45 - Pilots

2.75 - Turns

What temperature is it up there? What part of Michigan?

Do you have an idea when you will have it dynoed?

[L J VFR]

With my bike having bone stock exhaust, k and n filter, 3 total shims, and pilots out to 2-7/8 turns, Do you guys think I should put the bigger main jets from DD racing which i think are 105's ???, or should I stay with the 102's or whatever is stock. I don't remember..  It runs good, but are you guys saying there is a magical spot that can be found??? hehehe...   Lance