Dialing it in...need some advice

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midmoraider

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Hey all, I am really trying to get this thing dialed in. My current set up is this:

Morley Muscle Kit
152.5 mains
PAJ1 90
PAJ2 170
Stage 7 needles 2nd clip from blunt end plus washer in Sean's kit (2.5?)
A/F screws 2.5 turns out
Hindle 4-2-1 exhuast with IXIL can
Slides drilled and stage 7 springs
Floats wet level 16mm
Elevation about 700 ft

I recently pulled off the Hindle can and put on the IXIL unit. Sounds super nasty, but does a better flowing exhuast cause everything to go lean or rich? I had 155 mains in with the old can but went to the stock ones thinking I was rich. Now it seems to lag in the mid range say 3.5 to 5.5k. Once it hits above that it pulls really hard. With the 155's I was on the 2nd clip from the blunt with no washer. This seemed to stumble around the mid range with the new can, hence the washer.

I'm not sure how it's supposed to feel when it's really dialed in. This is the only Max I've ever owned and the po had a stage 1 installed when I bought it. I'd like to dyno it, but there isn't one nearby that will let me just do a couple of pulls. They all want to do the tune as well.

Sorry for the long post, I'm just trying to figure out if I'm even close on this thing. Never been able to pull the front end up when running through the gears, but spins the rear end pretty good. Any help or advice is greatly appreciated. Thanks.
 
If you can smoke your rear tire but not pull wheelies, you're prolly sitting forward a little too much! Try (carefully!) sitting back a bit and see what happens..

Changing your mufflers shouldn't really have any effect on your jetting - I would have left it where it was. But, only you know how it really feels as it's your bike and you know how it ran. If you've got Stage 7 needles you should have more clips to play with without using a washer. Did you try just going to the next clip away from the blunt end?

It's really difficult to get it perfectly dialled in without a dyno, maybe you should ride a little further to find a more friendly one?
 
I never really understood it but you may need to lean it out if the exhaust flows better now than before. Try removing the shims from the needle and see what happens. Taking notes is highly recc'd
 
I, am like you, don't really know exactly how a well-tuned Max should feel, for the same reasons. BUT, you can tell when it's stumbling and starving. At one point, you won't be able to tell and if you really want it perfect, you'll need to get yourself to dyno.

If I understand the gurus here, a more flowy exhaust makes you rich. Subpar midrange usually indicates the need for a needle tweak. I'd say richen it up by slowing clipping towards the pointy end.
 
I'd like to get it as good as possible for now, and hopefully get to go to Sean's dyno day later this summer if he has it again.

With the old set up (stage 1) it always smelled way too rich. Guys hated riding behind me. The jets at that time were the dj version of a 160. After reading through as much as possible and talking with Maleko, when installing Sean's kit I went with the 155's. Only reason I didn't go 152.5's at that time was I didn't have any.

One of the things I've noticed is that watching clips on youtube, other Max's seem to rev much faster than mine. Does this have to do with springs and drilled slides?

I had it on the 2nd and 3rd clip without the washer. 2nd was stumbling around like too lean, and 3rd was kinda boggy like too rich. 2.5 seems to be where it's happy, but still kind of lags through the middle revs.

Nin, I am thinking the same as you about the exhaust. The po had the Hindle system on without touching the intake. This makes sense to have the larger mains at that point. When I put Sean's airbox on, I believe that should have richened things up, making it necessary to drop the main sizes. Does this sound right to everyone?
 
ah crap, you responded to my post before i editted it. i'm pretty sure a more flowy intake equals more lean and a more flowy exhaust means more rich.
 
I've also noticed that folks who installed Sean's kit that have stock needles have much larger mains (for the most part). I'm trying to wrap my head around what does what and what affects what when changed. Does anyone have a flow chart that shows what a change to one thing, i.e. mains does to the rest of the components, i.e. a/f mixture, needle position and so on?
 
im at 700 ft, ive installed seans kit, needles, springs, air restrictors... everything except drilling the slides. im on the 3rd clip no washer, ive got 157.5, A/F in 2 3/4 turns. ive set the floats dry to 1.115 and ive got seans k&n airbox intake.

ive not dynoed the bike, but it doesnt stumble anywhere, its lightly sooty on the exhaust, but doesnt smell rich. no fouled plugs, seems to run awesome thru all rpms... the needles may be different from stg 7 im not sure.

id like some dyno time this year... id like to know where it sits. thats my set up. hope this info is of some help... probly not. lol good luck with your tuning.

peace,
evan...
 
I've also noticed that folks who installed Sean's kit that have stock needles have much larger mains (for the most part). I'm trying to wrap my head around what does what and what affects what when changed. Does anyone have a flow chart that shows what a change to one thing, i.e. mains does to the rest of the components, i.e. a/f mixture, needle position and so on?

here ya go. pay no mind to cut-away. it doesn't pertain to us.
 

Attachments

  • carbs101.pdf
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Another question, should you turn off vboost to really check your mains? Don't the mains come into play about the same time as vboost? To me it would seem hard to check when dumping two carbs into one cylinder. Maybe I'm just putting too much thought into all this.
 
Remember that vboost dumps two carbs' AIR AND FUEL into each cylinder, so it's not just more gas it's more mixture altogether.
 
midmo raider i have the same set up as you except a kerker with comp baffel. With the 155 mains the top end was weak, went to stock mains top end was great but had to move the needle clip to 3 rd down maybe i will try 2nd with a shim very pleased with the way the bike runs now hope this helps i still need to get it on a dyno
 
Remember that vboost dumps two carbs' AIR AND FUEL into each cylinder, so it's not just more gas it's more mixture altogether.

never understood why it goes rich. should just provide more 'mixture' not richer 'mixture'.
 
So where did you end up Midmo? I was doing some research reading and came across this thread, wondering what the outcome is.
 
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