New set up , fine tuning

[V4bandit]

Hey all! So far been loving the muscle jet kit. The fun factor is drastically improved lol

However, since the warmer weather has moved in I’m wondering if I have a rich condition now . I tuned the bike when it was about 5°C outside . Now that it’s about 25°C it feels like I’m losing a cylinder under load (bogging) until I get above 4-5k RPM and the bike just comes alive and pulls .

I’m thinking my needles are too rich and I should drop them back a clip what do you think ?

( my setup is posted earlier in this thread)

Thanks

 

[V4bandit]

Hey all! So far been loving the muscle jet kit. The fun factor is drastically improved lol

However, since the warmer weather has moved in I’m wondering if I have a rich condition now . I tuned the bike when it was about 5°C outside . Now that it’s about 25°C it feels like I’m losing a cylinder under load (bogging) until I get above 4-5k RPM and the bike just comes alive and pulls .

I’m thinking my needles are too rich and I should drop them back a clip what do you think ?

( my setup is posted earlier in this thread)

Thanks

I should add it doesn’t do it all the time. Usually after it warms up

 

[V4bandit]

Ok, I’ve now adjusted my needles to 2nd clip from blunt end and my A/F screws at 3.5 turns. The bogging down at mid rpm is gone . But now it wont idle for more than a minute or so without dying and exhaust pops like made when deceleration.

Also my mileage has gone into the tank. Hitting reserve at 150-160 kms
Any input would be greatly appreciated

 

[Traumahawk]

Ok, FYI, CV carburetors, will get richer, as they get warmer. So, set them to where they are perfect on a hot day, and you will be a little bit lean when it gets cooler.

1 question, did you resync after swapping the main jets?

 

[V4bandit]

Ok, FYI, CV carburetors, will get richer, as they get warmer. So, set them to where they are perfect on a hot day, and you will be a little bit lean when it gets cooler.

1 question, did you resync after swapping the main jets?

I did do a sync after swapping in the new jets. Now I’m thinking of going back to the 152 main?
But up top it pulls so nice.

 

[Traumahawk]

I did do a sync after swapping in the new jets. Now I’m thinking of going back to the 152 main?
But up top it pulls so nice.

Mileage is governed by the needles. To get your mileage back, the only thing that you can do is to go down to the first clip from the blunt end.......OR go the 152's (which is my recommendation) which will lean you out everywhere. If you stick with the 155's you will need to go leaner on the needles, and go leaner on the A/F screws.

 

[V4bandit]

Mileage is governed by the needles. To get your mileage back, the only thing that you can do is to go down to the first clip from the blunt end.......OR go the 152's (which is my recommendation) which will lean you out everywhere. If you stick with the 155's you will need to go leaner on the needles, and go leaner on the A/F screws.

Thanks Traumahawk
I’m going to swap the 152.5 mains back in today, and start the tuning all over from base line.
What are your thoughts on the stage 7 springs? Should I keep them in ( slides are drilled). Or play with that PA2 jet and go up to 177 ?

I’m in a crunch right now cause I’m signed up for a drag day this Sunday in Grand Bend, Ontario. So I want to have it right.

 

[Traumahawk]

Thanks Traumahawk
I’m going to swap the 152.5 mains back in today, and start the tuning all over from base line.
What are your thoughts on the stage 7 springs? Should I keep them in ( slides are drilled). Or play with that PA2 jet and go up to 177 ?

I’m in a crunch right now cause I’m signed up for a drag day this Sunday in Grand Bend, Ontario. So I want to have it right.

This is what Ive always heard. IF the slides are drilled, then you MUST have the stage 7 springs. If you think about it, the springs are what will close the slide (keep it pushed into the carb body), where as the air hole is creating a vacuum, and trying to pull the slide open (out of the carb body making the needles react quicker). If you have stock springs which are longer, and stouter, the the slides will stay in the carb body longer, and fight against the drilled air hole, which is trying to pull them out. I have read numerous stories of people getting a "flutter" at mid range part throttle that will drive you nuts.

The PAJ#2, will allow more air into the carb off idle all the way to redline. Unless you really rich in the midrange, i dont think the 177's are needed. I tried them on the 07, and didnt really like them.

 

[V4bandit]

So I took the afternoon and removed the carbs, swapped back to the 152.5 mains and I’m on 2.5 clip from the blunt end w/ 3.5 A/F turns.
Having a hell of a battle getting it to idle and the rpms hang slightly after blipping the throttle
Some what frustrating, but I know there is a light at the end of the tunnel lol

 

[V4bandit]

Update : I now have the a/f screws at 4 1/4 turns out and needles still at 2.5 clip from blunt. Running pretty good through entire rpm range, but pretty raspy/popping during deceleration.

It did feel like it pulled harder up top with the 155 mains though. So I’m confused now which way to turn?

 

[Traumahawk]

With carb tuning, its all about balance. So if you go richer up top, you have to go leaner in other places......and vice versa. Instead of looking at it as 1 "circuit", think of it as 3 circuits. Top end, mid range, and lower end. They are separate, but all influence each other.

So, these are my recommendations.
With 152's, 2nd or 3rd clip and see how that is. I'm inclined to go 3. It sounds like your lean in the midrange. Stay at 4 or 4.25 turns out. Ive had really good luck with going 1/2 a turn more on the rears. So 4 in the fronts, and 4.5 in the rear. (You will have to experiment what the bike likes, because every bike is different). You could do 3.75 in the front, and 4.25 in the rear. When the idle is right it will sound crisp, and just a little bit louder.
With 155s, 1st or 1.5 clips on the needles and 3 on the front and 3.5 on the rear. for the A/F screws.

Make sense?

 

[veebooster]

I like the 177s in PAJ2. I do feel my 155s leave me a bit rich in summer but it runs good so I left it there. I get 180 km per tank. Needles on 3rd clip A/F screws range from 3 to 3.75 every cylinder slightly different but generally richer in rear. Make sure your needles are moving freely in each carb. I had one sticking and it caused exhaust popping. Drove me nuts but I overlooked that simple observation. You are so close....

 

[V4bandit]

Thanks guys! I’ll play again tonight after work.

 

[V4bandit]

Well I think I got it pretty damn close. Thanks for your help Traumahawk!

I did the shot gun treatment even though I had the carbs off and cleaned. Went back down to the 152.5 mains, stage 7 needles on the 3clip from blunt, A/F screws 4.5 front and 4 rear.
Nice idle, crisp throttle response and very minimal popping ( almost none) while decelerating on test run.

See how she runs this Sunday at the drag strip, maybe some more fine tuning.(weather permitting)

 

[veebooster]

Awesome. Please update your Sunday results. Where are you running? I've ran some at St. Thomas but not in the last few years.

 

[V4bandit]

Awesome. Please update your Sunday results. Where are you running? I've ran some at St. Thomas but not in the last few years.

Hey veebooster, I made 5 runs at grand bend motorplex today. I was able to run 12.2 ( mph wasn’t working on the tree).
My launch is pretty slow I think, but every run would pop the front tire slightly. Which it wouldn’t do before the muscle kit was installed. So I feel the mid range pull has definitely improved

I do have to pull my carbs again though. Had to do a quick track side fix for a stuck float needle, almost thought I was trailering home, but was able to get it with the basic tool kit.

 

[Fire-medic]

You can shorten the stock CV slide springs with some safety wire, tie back a few loops and shorten them by a couple inches, that will work.

A Stuck float needle is usually because of debris from the gas tank. Change your fuel filter even if you just changed it recently. Change it again and take a really close look at the inside of your gas tank, any corrosion should be dealt with unless you want to continue to have trouble. The pilot jets are notorious for plugging giving you crummy idle and no fire on a cylinder at idle.

 

[veebooster]

Not bad at all. Your mph will give you an idea of HP.

 

[V4bandit]

That’s the only shitty part. The mph wasn’t printing on the slips that day. I kept forgetting to look down lol