Can exh packing effect jetting requirements?

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I went the Carbtune page, I would have ordered direct but I have that fear of it being held up in customs while my bike sits with incorrect jetting. I know this way it will get here fast. I'm really glad you guys jumped in with the recommendation.

I put the first ride in today after repacking the baffle. The difference in sound is negligible and had no real effect on performance either. It's still loud enough to make babys cry and HD guys pretend they don't see me :biglaugh:

As soon as the sync tool arrives I'll be digging in with the jets and needle adjustments. The recommended adjustments should lean it out considerably.
 

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I went the Carbtune page, I would have ordered direct but I have that fear of it being held up in customs while my bike sits with incorrect jetting. I know this way it will get here fast. I'm really glad you guys jumped in with the recommendation.

I put the first ride in today after repacking the baffle. The difference in sound is negligible and had no real effect on performance either. It's still loud enough to make babys cry and HD guys pretend they don't see me :biglaugh:

As soon as the sync tool arrives I'll be digging in with the jets and needle adjustments. The recommended adjustments should lean it out considerably.
I ordered direct and got it in 4 days.
 
I wish I had known he had it that well sorted. I wanted it to come quickly, I dont have a great deal of ride time before the rally comes. By the end of this month the roads here will be completely clogged with Harleys and the RVs/Trailers that bring them here, and other tourists.

I really want to get the engine dialed in before then so when things clear up I can go straight to enjoy mode! The local riding season is punctuated by heavy tourism and the Sturgis rally so one must allocate ones time carefully.
 
I got the Carbtune today. Thanks again gents for steering me in the right direction. This thing is a jewel.

I just got the carbs out and went down from 170 to 160 on the main fuel jets. I'm glad to have read about the toothpick trick. I removed a couple of the DJ Stage one needles and saw they were on the 2nd notch from the blunt end. I'll see where the jetting gets me before I start playing with the needle settings.

Will I need to readjust the idle mixture screws with the main fuel jet swap? I didn't disturb anything else on the carb assembly.

Thanks.


Oh, just for the sake of a conclusion to the title of the thread. The packing made no discernible difference in the drivability, or music levels.
 
Re: Can exh packing effect jetting requirements? 4k stumble.

Usually not....as long as they were pretty good to start with.

Sent from my SCH-R890 using Tapatalk
 
The bike ran great except for that 4k - 5.5k stumble.

I have it together now, I can get it synched but after a couple throttle blips it is slightly off again, also idle sounds different somehow, used to be a crisp throttle blip and it would return to idle quickly, now it takes it's time returning to idle, it just doesn't sound quite right.

Maybe I have to adjust the idle mixture screws to compensate for signifncatly leaner jetting... I'm proceeding with caution as this is my first go with the Vmax carbs.
 
now it takes it's time returning to idle, it just doesn't sound quite right.

Try synching again. I find that I often have a hanging idle after re-installing carbs. After synching, it goes away. Also, double check that carbs are fully inserted into boots, boots fully on manifolds, and all clamps are tight.
 
I think I got it sorted, the hanging idle was making it hard to synch properly, I just had to turn the idle down to 1k, and turn it down to 1k again, and again. After a few cycles of this I have it pretty much spot on, with the idle now a needle width over 1k and it has its ferocious bark back and no more hanging idle. It's consistently keeping the synch.

If anyone is reading this, I have to ad my endorsement for the Carbtune, simply a great tool.

I'll have to take it out for a ride later, my driveway is almost 3 miles of blissful washboarded, washed out dirt and loose gravel so I'll do it later when I have to go to town anyway.

Oh, and thank you again Traumahawk for the phoned in wisdom, cigars on me!:punk:
 
I think I got it sorted, the hanging idle was making it hard to synch properly, I just had to turn the idle down to 1k, and turn it down to 1k again, and again. After a few cycles of this I have it pretty much spot on, with the idle now a needle width over 1k and it has its ferocious bark back and no more hanging idle. It's consistently keeping the synch.

If anyone is reading this, I have to ad my endorsement for the Carbtune, simply a great tool.

I'll have to take it out for a ride later, my driveway is almost 3 miles of blissful washboarded, washed out dirt and loose gravel so I'll do it later when I have to go to town anyway.

Oh, and thank you again Traumahawk for the phoned in wisdom, cigars on me!:punk:

Good....glad that it helped.
 
Test ride today went well with the 160 jets installed. It pulled harder and cleaner than before and the stumble was reduced. I can still make it happen if I whack the throttle in high gear at 4k but the condition has improved.

I had the mixture screws out 3-3.5 turns and I stopped in Custer an turned them in to 2-2.5 and gained even more improvement, but still not perfect.

The stage 1 needles on the 2nd notch, I'll move them to the leanest notch next and see how that changes things. Definitely a step in the right direction with the jets though.
 
Some guys like to set their a/f mixture screws with the sync by turning them until they reach their max vacuum- then sync.
 
Just wanna say this forum rocks. Reading the replies back and forth is like listening intensely to a conversation between buddies while I suck back my beer.

+100
 
Pull up a chair! There is some good information going around. Without this forum I would be pissing up a waterfall for sure.

Oh yea, I might try that synch method of setting the idle mixture screws. Seems there are several good ways to do it.
I tried turning them in until the engine stumbles then backing out but it is hard to do by ear. When they were turned out to far it queefed a couple times and was a touch soft off idle. I'll play more with it after I get the metering rods set.
 
Ok, I moved the needles in to the leanest point this morning (from the 2nd slot) and the stumble is gone, it pulls cleanly from idle on up to redline. I had to play with the mixture screws a little to stop the occasional queef but after 5 hours in the saddle today I can say that it runs sweet.

No farts, queefs, stumbles or misfiring. It's setup exactly where Traumahawk suggested I start. It really felt lean, never thought that rich felt the same way. I'm gald you guys know your shit!! thank you guys!
 
Ok, I moved the needles in to the leanest point this morning (from the 2nd slot) and the stumble is gone, it pulls cleanly from idle on up to redline. I had to play with the mixture screws a little to stop the occasional queef but after 5 hours in the saddle today I can say that it runs sweet.

No farts, queefs, stumbles or misfiring. It's setup exactly where Traumahawk suggested I start. It really felt lean, never thought that rich felt the same way. I'm gald you guys know your shit!! thank you guys!

I'm glad that it worked for you.
 
:deadhorse:

Ok, got a chance to take a good solo ride today with a friend. (DJ160 mains and metering rods on the leanest setting) and I believe it's still rich. The stumble is mostly gone but under select conditions I can see a hint of it still present, although not bothersome it does indicate that I may still be a little on the rich side above 4k-ish

The guy I was riding with told me when we stopped at Boondocks that he could smell it when I got on it, being a tech I know that he knows what rich smells like.

I cant help but think that I have this thing leaned out quite a bit already. Is the DJ jet kit really THAT far off from what works in the practical real world?

The 160s were the smallest jets in the kit. The only way I can lean it out even more is to use the air jets DJ150. I'm bringing this up guys because I'm apprehensive about getting it to lean and cooking some valves. Would it be my next logical step on do the DJ150 air jets or should I order another step down on the main jets. Seriously with the metering rods all the way in I'm wondering if I'm about where I should be or if it is unusual to have to lean it out so much to nail it correctly. So here I come to beat the dead horse!

One thing that really sucks is that the jetting kit only has 3 of the DJ150 air jets, one is missing. Also one of the factory jets are missing.

If any of you hvae a loose DJ150 air jet rolling around I'll be happy to buy it via paypal, just need one. Also I have an OEM main jet missing so would love to get my hands on one of those to.

How much bigger are the DJ160 over the OEM jets? I cant see any numbers on them and dont know if they are DJ or MK compatible numbers.

Thanks again guys, I promise to use all that I am learning to help others!

Tony
 
DJ160's = Mikuni 150's.
The stock jets are Mikuni 152.5's.
A lot of guys run Mikuni 147.5's.
DJ150's = Mikuni 140's and would be way to lean IMO.
Look at the jet comparison charts I attached.
 

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Thanks, once again your awesome. I'll be ordering the 147.5s From Sean tomorrow along with the fork parts and HL upgrade.

How is Dynojet still selling these kits being so rich? It was rich enough that I could have ridden on the moon with it setup according to the directions.
 
I don't know, but DJ165 should work with a full exhaust with big diameter muffler (very loud set up)
Otherwise it will always be too rich, MK 147.5 to 152.5 jets are in the good range ;)
 

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