New Voyager-Performance Mod Installs

[Netnorske]

Well early this week I dropped the bike off for my long awaited install of my V&H pipes, PCV fuel module and the Thunder BAK. I must say, that performance-wise, even without the benefit of a dyno tune, this thing is officially a beast . With the quick-turn throttle mod and all this other good stuff, this bike flat gets up and goes. I can be in 5th gear at 65 mph....roll on the throttle and leave you like you were standing still....it's THAT powerful. That's the good news.....

The bad news is that there seems to be a lot of what I would call, unusual and undesireable noise coming from the intake itself. Along with the suctioning noise of more air entering in, there is also a very noticable and substantial knocking noise coming directly out of the intake and some occasional back-fire like popping on decel.

I emailed Thunder to see what they said about that and here is the response I got from the tech....

"Kris,
We are finding out that a lot of 1700's especially the Vaquero's have an intake leak at the throttle body to intake manifold seal. I have done 2 bikes in the last 2 days that have had this issue. We are working on a gasket kit that will seal up this leak which help with the noise and also decel popping issues.
Travis"

BAK's are nothing new and the intake assembly should easily support the Thunder Kit, but I suppose this weak seal may be the culprit, and a vacuum leak could indeed possibly be causing the unwanted noises.

I bought the Thunder Kit when I purchased the bike and had the dealership install it, along with the pipes and PCV....so today I called to express my concerns about a possible vacuum leak and explained what I was hearing. I essentially put the onus on them. If it is indeed a vaccum leak due to a weak seal between the TB's and intake manifold....it seems reasonable that this should be a warranty issue does it not? Or would they say that the BAK is the cause and not cover it? Regardless, I have an appointment next Friday to have them check it out. If they find no such leak...I will most likely be putting the OEM air boxes back on the bike as the knocking sound through the BAK is just a little too annoying.


As for the V&H pipes...they sound good.....different than on my 1600, but for sure have that aggressive rumble. It is hard to yet judge them on their own merit however since I have other sounds coming from the intake that are obstructing the clean sound of just the pipes. I imagine if I end up going back to the OEM intake set-up....the pipes alone would sound pretty nice. For now....my immediate mission is to deal with this intake and figure out what is causing the knocking sound, or better yet....let the dealership figure out what might be causing that. If that can get quieted down by fixing a vacuum leak....I will be a pretty happy camper!


On another note....Corbin has my seat back in their factory, but apparently only one guy works on the modifications (if you can believe that...I can't). He was out of the shop working the Sturgis Rally for a couple weeks and as a result, is pretty backed up in the factory. Bottom line is it might be three or four weeks before I see my seat again.....


My must do list is getting shorter...

- fine tune intake issue- fix bad seal or return to OEM
- get my seat perfectly modified and installed
- order/install a set of 13" Progressive Shocks to get bike a tad lower

Then it will be all the little BS bling, like saddlebag top and side rails...stuff like that. It would be a lot easier if I just won the lotto.....

[Sin City Stan]

Kris,

I seem to remember a post by Ran N Ray about the same problem with the intake leak. If I remember correctly he actually had to do machining to cure it. My alcohol addled mind seems to remember this lengthy and informative post was on the VROC Forum.

Good luck.

[cactusjack]

Stan beat me to the punch, but I would guess poor machining tolerances are to blame. The throttle body and intake manifold aren't mating up well.

You're going to get some noise with a more open intake. Back in high school, we used to flip the air cleaner covers over on our big V8 4 barrels and when you'd nail the gas pedal it roared like crazy. I don't think it made the car much faster, but it sounded really cool (at the time). That big v-twin is sucking in a lot of air and it's going to be noisy. You shouldn't hear a clanking noise, but you should hear the engine gulping a lot of air.

[Netnorske]

Originally Posted by Sin City Stan

Kris,

I seem to remember a post by Ran N Ray about the same problem with the intake leak. If I remember correctly he actually had to do machining to cure it. My alcohol addled mind seems to remember this lengthy and informative post was on the VROC Forum.

Good luck.

I too remember reading something about that...and it seems it is becoming one of those "known issues". My hope is that the dealership will take care of it under warranty if such is the case..... The bike runs like the wind now....so I would really like to just eliminate the knocking noise and call it good.

[Sin City Stan]

Originally Posted by cactusjack

Stan beat me to the punch, but I would guess poor machining tolerances are to blame. The throttle body and intake manifold aren't mating up well.

Poor machining tolerances?? That's a nice way of saying the engineer(s) screwed up. The machining is CNC controlled. It only does what it's told to do. IMO this is hard to imagine this happening in the era of AutoCAD and 3D modeling. Just plain sloppy.

[Top Cat]

I read about that machining problem so it has to be on this forum somewhere as this is the only one I read.

[chainsaw]

Drop a can of STP in that puppy. You won't hear the knocking.

[Sin City Stan]

Here you go Kris. A quick search thanks to TC and here it is.

http://www.vulcanbagger.com/forums/s...hlight=racnray

[1oldtimer]

I have been reading a lot about the noise one gets after installing a BAK or the like. From pictures that I can see, it looks like the air comes in from the filter and then gets sucked into the T/B flat off the bottom of the backing plate. Almost like a whirlpool for explanation purposes. I am no expert, but from past experiance with bikes and cars alike with a T/B system, would we not want the intake air to rise up off the backing plate a tad bit before being sucked into the T/B? To explain better, a ridge about an 1/8" high around the intake holes of the backing plate. Maybe this has been discussed already, but I havent seen it and apoligize if I am repeating an old thread. But I am eventually going to get an aftermarket air filter and have been curious about the "pounding" noise some of you talk about. Just my .02 worth and hopefully a more valued expert will understand what I am talking about.
Frank

[ringadingh]

Originally Posted by chainsaw

Drop a can of STP in that puppy. You won't hear the knocking.

They still make that stuff? I haven't seen it around for years.
I used to put in in one of my cars, and it would raise the oil pressure 10psi and hold it there for the entire oil change.

[smokey]

Well I am glad you got a quicker answer from Thunder manufacturing than I seem to be getting, I ordered the backing plate when I got the hypercharger from them, the backing plate was not machined correctly and they were made aware of the problem, that was months ago, still waiting for a replacement and still waiting for a reply to my email. I was told they would get right on it, that was over 2 months ago, I won't deal with them anymore.

[jestephens]

If you're running the PC-V straight out of the box, there is no advantage to your fuel mix. The stock map is all zeros. -That "knock" could actually be a "Ping".
Mine had the same, but after I downloaded someone else's map it got better. Then I modified the map matrix by my own observation, and it's MUCH better. As soon as I get it on a Dyno I suspect it will be perfect.
Just my observations -

[RACNRAY]

The "knock" is normal and NOTHING to be alarmed or concerned about. It is called INTAKE NOISE and is found in ALL engines. We don't hear it because the stock intake susyem is designed to minimize intake noise, both for OUR enjoyment of the skoot and help the skoot meet our federal noise limits. A decibel meter measures noise, and does not decern the difference between engine clatter, exhaust noise ,or the noise that intake systems make. So the manufacturors must employ many methods to suppress these noises.

I have the noise, it has been there ever since I designed and installed my BAK. It is not bad at all. These 4 valve engines make alot of intake noise, tho it seems that certain BAKits allow more intake noise than my design.

Bottom line, the noise is to be expected as you have removed the stock intake which was designed to MINIMIZE intake noise. You now have an open intake not too far from your ears, so your gonna hear things. Fixing intake leaks is a good thing but does not and will not eliminate intake noise like the knocking that is heard.

RACNRAY

[Netnorske]

Originally Posted by jestephens

If you're running the PC-V straight out of the box, there is no advantage to your fuel mix. The stock map is all zeros. -That "knock" could actually be a "Ping".
Mine had the same, but after I downloaded someone else's map it got better. Then I modified the map matrix by my own observation, and it's MUCH better. As soon as I get it on a Dyno I suspect it will be perfect.
Just my observations -

When the dealership installed it....they used a map that included V&H pipes and OEM intake as they could not find one with my exact accessories. I wondered too if a true dyno tune would help. The knocking is worst from 2200 to 2800 rpms....less over 3000, but most of the time I'm cruising at around 2500....so it sucks pretty bad. Tomorrow I am going to put the OEM airboxes back on and see if there is any real difference in performance. If not, I will probably just stay with those.

[SoCalNomad]

As far as intake leak info goes, Racnray posted a bit more detail in a post on the Kawasaki Vulcan Forums:
http://www.vulcanforums.com/forums/s...ad.php?t=21798
Great pics too, thanks Racnray!