Stage 1 jet kit questions.

[mavgrab302]

First time posting but I have been reading alot of the threads but haven't read anything quite like my problem. I live down near Houston and recently bought the stage 1 kit that has me ready to shoot the max out of frustration...lol
This isn't my first rodeo working on carbs either but it never hurts to get advice from someone looking in sometimes. Prior to this install I cleaned the carbs, visually checked bowls, sync and put it all back together stock
I installed the kit just as directed.. used 170 mains, drilled the slide, used DJ spring, #3 slot on DJ needle and didn't put the 150 pilot jet in at first.
The bike has a K&N, 4to4 cobra slants ex.
Bike ran like crap idle-3.5k, played with the mixture no real change. Seemed lean so I put the DJ150 pilot jet in and helped alot although now instead of acting up going down the road it dies sometimes while stopped or putting it in gear or just taking off at low rpms 1k. nothing seems constistent, no matter if the mixtures screws are 1 turn to 6 turns...lol ofcourse this goes without saying I have tried to find the highest rpm with the mixture but if it does help it only lets me pass two or three stops then goes to trying to die in the middle of my turn. what it does is just ABRUPTLY stall then goes like nothing is wrong.
The best I have had it so far is with #3 groove on the needle
3 1/2 turns and changed pilot jet to 160, rarley happens now but still not good while turning even if it happens once.
I've done the shotgun fix when I put the jet kit in, carbs are synced, but if this problem was constistent I could narrow down the problem at this point I just feel I need to split the rack and clean the carbs thoroughly..lol

 

[KJShover]

Stg 1 is the ******* child of the DJ line. you should'nt need a kit with slip-ons. especially the cobras. Your limited by the size of the stocker main tubes and won't gain really anything 'cept a different growl. All that really needs to be done with a slip-on system is just a 147.5 main jet and a little a/f screw adjustment.

I'm thinking your probably running too rich. have you checked your plugs to see what they look like?

 

[Thevmaxrider]

I would rip out the DJ jets, put in stock Mikuni 152.5's. Put the stock PAJ's back in, keep the DJ springs and even the needles are ok. Re-synch and go from there. You will really only see a benefit from a jet kit, recommending Sean Morley's Muscle jet kit, if you have a full exhaust system installed. Slip ons give no real performance enhancement and the Cobras actually lower the HP output of the bike.

 

[mavgrab302]

Plugs look perfect... cobras have been drilled out at the plate between the baffles aswell not much difference I'm sure. think I will put everything back stock except for DJ 165 mains and springs, I did drill the slides though which will make it run lean correct?

One other issue I have had with bike ever so often after a bump or sometimes after getting gas the bike will act like it drops cylinders "won't take gas and sounds airy" and the tach will be reading super high even though the revs aren't more than around 3k, I'msure someone has had the problem. Thanks for the input fellas

 

[Thevmaxrider]

Your symptoms indicate, to me, that you may be experiencing a failure of the CDI box. This exact issue happened to me with Toxic when mine burned out.

 

[gamorg02]

check it with a morley exchange program?

 

[4gasem]

Plugs look perfect... cobras have been drilled out at the plate between the baffles aswell not much difference I'm sure. think I will put everything back stock except for DJ 165 mains and springs, I did drill the slides though which will make it run lean correct?

One other issue I have had with bike ever so often after a bump or sometimes after getting gas the bike will act like it drops cylinders "won't take gas and sounds airy" and the tach will be reading super high even though the revs aren't more than around 3k, I'msure someone has had the problem. Thanks for the input fellas

With Cobras you NEED to put in 147.5 Mikuni jets to get the AFR closer to optimal. Anything richer than that and you're loosing more HP. What you may not know is the Cobras actually restrict flow MORE then the stock exhaust so you need to lean it up a bit. By bolting on Cobras you are removing probably 10HP. I've seen a few on the dyno and I think all of them were in the 95hp range.

Chris

 

[mavgrab302]

Good stuff, I was looking into either buying or finding someone to fabricate a 4-1 exhuast much like the UFO drag series.
One problem with going back stock on the carb....I drilled the slides...figure I canJB weld the hole and redrill to stock but don't recall the original hole size..any one know.
Thanks for all the help fellas

I will say this about the jet kit though..on the top end it does push the bike better just stinks off idle

 

[4gasem]

Try it with the slides drilled. This is one reason I decided against drilling them. It really just allows them to move quicker I believe. You COULD JB weld them and redrill but you run the risk of it falling out and getting sucked into the engine.

UFO blows! Don't buy jack **** from that A hole! He's Bi polar or something...

Get a hold of Marks and have him make you a 4-2-1 or go with Kerkers setup you'll be money ahead and you won't have the huge potential of getting screwed over...

Chris

 

[mavgrab302]

Bi-polar....lol nice to know, obviously been screwed by them.

 

[4gasem]

Along with many others!!!

 

[mavgrab302]

Ok put everything back stock except for the DJ springs, have to use the drilled out slides ofcourse. out of 6 stop and go turns it only once momentarily stalled "1 sec. cut out like has been happening" but boy does it really like the smaller spring, it screams to red line now, very responsive right off idle....ashame I bought the whole kit.. going to play with shimming the stock needle next.

 

[4gasem]

Awesome! I wish people could all come here first so we could save them moola!

 

[mavgrab302]

Yeah, guess next move is to find someone to fab me some pipes or cough up a chunk a change and buy some new ones. Seems like the problem isn't so much the cobras as much as it's the headers. Cobras have split baffles in each pipe, one of the first things I did was drill out the plate between the two (1" dia.) I guess, sounds alot meaner but I guess still to restrictive. Anyone know of someone that can fabricate vmax headers "or atleast the rear headers" around houston?
One thing I may try next is removing the baffles totally somehow...

 

[one2dmax]

It's not that they are too restrictive it's that they have no scavenging ability since they make the system a 4 in to 4. Do some research on exhaust flow and the noted keyword which will help you better understand what I am saying.

The stock main pipes do have some restriction too but we've made well over 130 rwhp with stock pipes/mufflers and 100cc increase in bore (with a very high mileage engine).

Sean

 

[mavgrab302]

gotcha on the scavenging, so on a max whats a decent exhaust buy with the headers and can accept jet kits?4-1, 4-2, 4-2-1 ?
I like alot of racket and something that sounds mean, really like to stay as low in price as possible, any suggestions?

 

[one2dmax]

Pretty much ANY aftermarket full system can use a jet kit (mine or stage seven). Also, they will work without a jet kit but just not to the fullest potential. You would like a Kerker then with comp baffle. My supplier is currently out of them and it's looking like it will be the end of the month before they are available. This doesn't mean you want to wait until that time to commit though. Check out our website for pricing (you won't find much lower anywhere).

Sean