Oh Boy, fighting the jetting fight......:(

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I too am tuning my self sourced muscle jet kit. Its early Saturday morning so after today I will be able to post all jet sizes, needle adjustments and spring lengths along with results. Thanks to a forum like this I can get real time help and advice and maybe offer the same to guys doing the same mod as me, he's in Cambridge, I'm in Denver. Thanks to all who contribute!
 
Don't some guys looking to save a buck tie-back w/safety wire the springs, to get a shorter length?
 
Alright. I’m about one step away from ripping everything “vmax”, cop and/or ignitek off this bike and going back completely stock Venture!

Arrgghh!

So, a question for Sean Morley:

Does a stock VMax airbox fit under the stock Venture air box cover / faux tank? Thats with the full vboost system.

If it does, i may make one last ditch attempt at getting this sob to run right with a stock vmax airbox.

If it doesn't fit, or the stock airbox doesn't get it running right, i may rip it apart from the head gaskets up in total defeat and go back stock venture all around.

I’m tired of fighting this damned thing and pouring money in to it. Ive had enough and just want to ride it (trouble free) again.

Vboost is intoxicating, but it worked fine in stock venture form. At least, i spent more time riding it than working in it. Now i work on it more than i ride it. Not what I want in a bike. I guess i just got sucked in to the alure of more power a la vmax....
 
Well.....“F” it.

Ordered a used vmax airbox off ebay.

If it works: great. It wasnt all money down the drain.

If it doesn't: buying a set of head gaskets and ripping the f-er apart....
 
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The venture we built did let the vmax airbox fit in place. We had also used the Vmax manifolds and vboost components. The carbs were a very very tight fit and cables needed some tweaking.
 
The venture we built did let the vmax airbox fit in place. We had also used the Vmax manifolds and vboost components. The carbs were a very very tight fit and cables needed some tweaking.

Did you have issues with the battery box? I belive the vmax airbox is shorter than the venture’s but i think its wider and goes further forward, where the venture battery currently lives....
 
Did you try the 40 pilot jets? I know when I was tuning my vmax it really didn't like bigger then stock pilot jets.

Sent from my SM-A520W using Tapatalk
 
Did you try the 40 pilot jets? I know when I was tuning my vmax it really didn't like bigger then stock pilot jets.

Sent from my SM-A520W using Tapatalk

Not yet. Shop was supposed to let me know when the parts came in at the end of last week. I thought about is sat morning as i wanted to do them this weekend. I called 5 mins after 12 and they had shut down at 12. So I’ll have to call in the morning.

For now, this is how it sits:

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Sucky thing is the venture frame doesnt have the clearance to remove the carbs. Evry time i have to jet or change something internal, i have to drop the front motor mounts (and all the venture plastic) in order to just pull the carbs. Major pita every time...
 
So, I'm planning out moving the battery to fit a vmax airbox;

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Cardboard box is the size of the battery so I don't have to deal with the battery weight in mock up. The battery has to go down in order to move forward under the cross brace. I thought of using a gel battery so I could mount it on it's side and slide it further forward, but that just more expense and frustration. I've had enough of both of those at this point (ie: expense and frustration). I want also to stick with the AGM battery since it's easily replaced locally. A gel battery would not be.

Unfortunately, this eats up the space where the Vboost motor and MAP sensor reside.

The map sensor is an easy move, but the Vboost motor is a different story. The cable limits where and how you can position it without getting the cable all bent and bound up.

I can make it fit under the battery. But it' super tight and when I get a battery bracket in there it's highly likely there won't be enough room for all of it without contacting something.

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Not to mention, it's very close to the valve cover the reflected engine heat and right behind the radiator. it would be so tight, there isn't even room for a heat shield. Not good for the lifespan of any electrical component.

However, on the back of the engine, there's lots of available real estate right about where the vboost motor cable would position it, if the vboost linkage went backwards instead of forward.

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(I have no idea why supermotrs photos never seem to post the right way up, sorry)

So, off the carb rack is going to go and I'm going to look at turning the vboost manifolds around backwards to potion the vboost motor to the rear. They look symmetrical, so it should work.

If the mounting flanges to the engine won't flip, I'll look at taking the center tubes out and reversing those.

One way or another, I'll figure this bugger out.

Then I'll try and get at least the rest of the riding season out of it. Once the new shop is set up and I'm not working in a pile of moving boxes, I may look at building a custom header to go with the R1 muffs.

But I may just leave it alone and ride for a few more seasons. I'm tired of working on it and want some payback. Plus, I'm not even sure headers would be worth it on this near 1000 lb rig......
 
How about mounting a lithium battery in a saddlebag?

Thats a decent idea and the bike sure could use moving some of it’s “up high” weight to a lower spot, but that would be more expense, harder to source replacement battery and I’m not completely sure I’m going to stick with the 86+ saddle boxes.

The 83-85 side boxes make the bike look so much smaller l, but st the cost of reduced storage space.

Until i get my head locked down to the 83-85 boxes or the 86+ boxes, i dont want to do anything that would commit me to using either set exclusively.
 
Well, flipping the vboost manifolds around was a good idea, but its not going to work.

Linkage won't clear the csm chain adjuster.

Have to figure something else out i guess.

Those original Venture heads sitting over on the shelf are looking better and better every day....
 
Have gou considered using individual filters like a stage 7 setup? Seems it would solve your space issues.

Sent from my SM-G930V using Tapatalk
 
Have gou considered using individual filters like a stage 7 setup? Seems it would solve your space issues.

Sent from my SM-G930V using Tapatalk

Same idea is why I’m fighting the cv carb gremlins. I was, essentially, working with an open panel filter (like the morely kit). As far as i can tell, its causing me all sorts of issues, even with the air correctors.

I had it running pretty good, but abysmal fuel mileage. As in; low twenties, even with a light throttle hand. That just will not do.

So last ditch effort in to install a stock vmax airbox and see if things work.

If not, i may run up the white flag and just rip all the vmax stuff off the bike...
 
Alrighty!

I went back out to the bike and started trying to formulate a plan. I looked at the battery again and it turns out i bought an agm battery last time at the local parts store.

Agm can be mounted on its back if needed. Well, that will solve my space problem quite handily and obviously, they can be sourced locally.

The battery will slide up between the frame rails to the headstock like it was meant to be there. I just have to re-route some of the wiring harness.

Just to be sure, i laid the battery on its back on a piece of cardboard. If the cardboard is still dry in the morning, its a go.

That will leave plenty of space under the battery to mount the vboost motor and a few other components i need to package somewhere. A nice littlw heat shield for it all and everybody’s happy!

:)
 
Deed is done:

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Hopefully, thats enough room to fit the vmax airbox. All i have left to do is make a couple small brackets to hold things like the map sensor.
 
Well....crap.

I both like it when i find something wrong...and i hate it.

I have a vacuum reservoir on the bike to damp out the intake pulses before they get to the map sensor. Nothing big, just a small chamber that makes for a more stable signal. As i’m getting ready to remount it to the bike, i notice one of the barbs is angled strangely. Closer inspection reveals the barb has torn the hole sideways and leaking vacuum.

Well, shite.

Was it running fine before and the crappy mpg becuase it was running advance without map sensor input or was the airbox still the problem?

There’s one thing about it for sure; it wasnt helping the whole process.

Also might explain why it was so hard to sync to #2 as the vacuum line comes off #2. With what was essentially a vacuum leak on #2, things would have been all wonky from the get go. The leak was huge (applied vacuum to the lines and it wouldnt bold) but a vacuum leak of any sort at that point is going to make things go all funky.

Oh well, i’m commited to the vmax airbox now. Guess i’ll see what i get.

Wish I’d found that damned vacuum leak earlier.

I dont remeber the ignitek readings being really “off” when i checked them. But then again, I wouldnt have noticed it anyways as i only had the laptop hooked up at idle, where it would be on base timing...
 
Grabbed this while I was at the shop yesterday
 

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