What did you do to your Vmax today? Part 2

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Vince if you only adj. the a/f screw you will only lean it out to 4000rpm. You will still be way to rich from 4000 up. You need to lean out the main jets and then shim the needles to make the mid range a little richer. Re read Eric's post and you'll understand.
 
Vince if you only adj. the a/f screw you will only lean it out to 4000rpm. You will still be way to rich from 4000 up. You need to lean out the main jets and then shim the needles to make the mid range a little richer. Re read Eric's post and you'll understand.

I get that I will only be making changes up to the 4krpm range and I am good with that for now since when I do cruise that's where I am. I have not noticed any stuttering at 5rpm for now. I will tackle the next hurtle after I review how to change the main jets and shim the needles. I can work on cars all day if it's pulling off heads, working on a timing chain, etc., but when it comes to anything that is big hand challenged I have to enlist someone with smaller and steadier hands. My patience runs thin on what I call puzzles. Hence I dont do puzzles or play video games.
 
Probably should move to Carb section. I will purchase the necessary items and peep out the carbs and see if I can personally do this myself.

upload_2019-9-25_14-30-24.png
 
Well no matter where I adjusted the a/f mixture screws nothing changed. Started at 2 turns out on all 4. Took a test ride. Stuttered at 3500 to 5500rpm. Went to 1.75 turns out. Stuttered at 3500 to 5500rpm. Went to 1.5 turns out. Stuttered at 3500 to 5500rpm. Went to 1 turn out. Stuttered at 3500 to 5500rpm. Went to 3 turns out. Stuttered at 3500 to 5500rpm. Went to 2.5 turns out. Stuttered at 3500 to 5500rpm. Went to 3.5 turns out. Stuttered at 3500 to 5500rpm. Went to 4.0 turns out. Stuttered at 3500 to 5500rpm. This was all done b4 the sun went down and tested in 4th gear and once in 5th and made no difference. Clearly something else is wrong. I dont know any VMAX wrenchers near Lakeland.
 

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Well no matter where I adjusted the a/f mixture screws nothing changed. Started at 2 turns out on all 4. Took a test ride. Stuttered at 3500 to 5500rpm. Went to 1.75 turns out. Stuttered at 3500 to 5500rpm. Went to 1.5 turns out. Stuttered at 3500 to 5500rpm. Went to 1 turn out. Stuttered at 3500 to 5500rpm. Went to 3 turns out. Stuttered at 3500 to 5500rpm. Went to 2.5 turns out. Stuttered at 3500 to 5500rpm. Went to 3.5 turns out. Stuttered at 3500 to 5500rpm. Went to 4.0 turns out. Stuttered at 3500 to 5500rpm. This was all done b4 the sun went down and tested in 4th gear and once in 5th and made no difference. Clearly something else is wrong. I dont know any VMAX wrenchers near Lakeland.

It stuttered because the area that is governed by the needles is too rich. So, you have two options.....lean out the needles (if they are adjustable, and if they are, you will raise the clip closer to the blunt end, to make you leaner in that area), OR drop the main jet size by 2 (assuming that you have stock jetting, which I figure that you do.) to 147.5's, and if you have stock needles, you will need to shim them to richen you up.

Let me know what you game plan is, and I can post the information up on how to walk you thru all of this.
 
It stuttered because the area that is governed by the needles is too rich. So, you have two options.....lean out the needles (if they are adjustable, and if they are, you will raise the clip closer to the blunt end, to make you leaner in that area), OR drop the main jet size by 2 (assuming that you have stock jetting, which I figure that you do.) to 147.5's, and if you have stock needles, you will need to shim them to richen you up.

Let me know what you game plan is, and I can post the information up on how to walk you thru all of this.
Whichever is the quickest. If I have to pull the carbs off I will have to put that off until I have a free day. I am good with trying whichever that would work.
 
I admit to not being an expert on the subject but whenever anybody I know has fitted free flowing exhausts they have made their fuel mixtures richer not lean to make them run right, maybe it's a UK atmosphere thing
 
Well this long term project is another lesson in I should have left well enough alone. Changes to the exhaust are made and now I will fix the new issues. I will pull the carbs off as soon as Traumahawk provides the instructions on whichever route is best suited for the VMAX. I dont race and I dont ride her much, but when I do want to cruise I would like it to run right.
 
I admit to not being an expert on the subject but whenever anybody I know has fitted free flowing exhausts they have made their fuel mixtures richer not lean to make them run right, maybe it's a UK atmosphere thing

Either that....or its a float level thing. My floats were set at 17 mm when I had Dannymax rebuild my carbs. Before the rebuild, with 147.5's my A/F reading was right at 13.0. When Danny took my carbs apart he said that the floats were set at 12 mm (and to the best of my knowledge, they had never been rebuilt.....so super rich from the factory, they are supposed to be between 15-17 mm.) Now, with 155s, my A/F reading is 13.6. So, my jetting is 1 step richer than stock, but my A/F reading is .6 leaner than what I was at 3 jet sizes leaner.

Here is a pic of the 07. You can see the O2 bung welded into the exhaust just below the right passenger footpeg. I used an innovate LM2 to get A/F readings while riding around to give me real world numbers. https://www.innovatemotorsports.com/products/lm2.php

The A/F numbers that I got for uptop, were taken at the dyno. What i basically did was put the bike on the dyno and continue to do runs, until the HP numbers would fall off, typically run 5 to 6, and then make a change. 66138673_10220338310067107_8642697530791952384_o.jpg
 
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Whichever is the quickest. If I have to pull the carbs off I will have to put that off until I have a free day. I am good with trying whichever that would work.

Here is some information that should help.

How to replace the jets.

https://www.vmaxforum.net/threads/how-to-change-main-jets.3570/

After jet changes you WILL need to sync the carbs.

https://www.vmaxforum.net/threads/how-to-sync-carbs.3959/

Here are some pics that Sean posted a while back, on the various needles and what they look like, although I suspect that you have stock needles.
IMG_20170130_164301041.jpg

IMG_20170130_164316214.jpg

Here is also some good information on how to clean the pilot circuits.

https://vmax.lvlhead.com/tips/shotgun.htm

Hope this helps.

Eric
 
A lot of valuable information. I will review and plan a date on the jet changes. :)

Here is some information that should help.

How to replace the jets.

https://www.vmaxforum.net/threads/how-to-change-main-jets.3570/

After jet changes you WILL need to sync the carbs.

https://www.vmaxforum.net/threads/how-to-sync-carbs.3959/

Here are some pics that Sean posted a while back, on the various needles and what they look like, although I suspect that you have stock needles.
View attachment 70168

View attachment 70169

Here is also some good information on how to clean the pilot circuits.

https://vmax.lvlhead.com/tips/shotgun.htm

Hope this helps.

Eric
 
Thanks.
Yes, the tank has been modified to hold a bit more than 5 gallons. When I bought the extended swingarm from Sean Morley, I asked if they made one. He said they never did one before but would give it a shot.

It may not have been a really wise investment for me since I need to get off the bike and stretch sooner than every 150 miles. But it is convenient to not have to fuel up as often so it gives a bit of leniency when planning fuel stops.
I too have a 3" stretched swingarm with a Morley 5 gal tank and the most miles I got out of one tank was a little over 170 miles. It took nearly 5 gallons to fill it up, it was at that moment I realized my reserve sensor was not working! (broken element in tank) I tried to use the Vmax as a long distance rider by riding it to and around Newfoundland but in the end it just didn't work for me. I now have '16 Super Tenere ES with a 6 gal tank and a 50 mpg average, comfortable seating position and cruise control which eats up miles very easily!
 
Update on my situation. John Furbur came to visit for a couple weeks. While here he discovered the shims was missing in the right rear carb needles. He put all new shims in all of them and now she peforms as she should. :) No clue why a shim was missing and didnt notice any issues on the stock exhaust with slip ons.
 
Update on my situation. John Furbur came to visit for a couple weeks. While here he discovered the shim(s)was missing in the right rear carb needle(s). He put all new shims in all of them and now she peforms as she should. :) No clue why a shim was missing and didnt notice any issues on the stock exhaust with slip ons.


Sounds like a shim was lost sometime, but all's OK now. Ride & enjoy.
 
Hagendaz!! Just when I thought I'd seen it all. Here's an old pic of my bike in it's early state of mod monkey along with an old Chang Jiang BMW side car, 750cc, 4spd with reverse.042913165626.jpg
 

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