Vaquero intake leaks

[Monkeyman]

You got me kinda lost but that's ok. The V&H FuelPak doesn't have the same kind of adjustable pots as the Dobreck, etc. It has about 35 different values you have to input to map it. These are given by V&H directly and I wouldn't have any idea which ones to change. Guess I'll leave well enough alone and keep the temp sensor where it's at. Thanks.

[RACNRAY]

I spoke to a forum member yesterday that had seen this thread when I first posted it and had disasembled his Vulcan Classic and found a few interesting things.

First his posts were taller than mine by about .006". The sealing surface on the intake manifold was warped by about .010", and the o-rings that seal the manifold to the intake ports had small tears in them.

He has a friend that owns a machine shop, so he had the throttle body machined flat and block sanded the intake surface flat. He had put it all back together with new o-rings quite some time ago but the weather and road conditions where he lives prevented him from riding his skoot, till yesterday.

His findings were the acceleration was very much improved, the backfire on decel was reduced about 50%, and he had a hesitation since new, even after his ECU was replaced that is now completely gone.

I experienced the same improvements so from what i see here the occurance of some percentage of vacuum leaks may be plaguing Vulcan owners.

I have a customer that just bought a Vaquero, he has some strange things happening with it's low speed running, so after he has the skoot broken in it'll be here for dyno work and to check him for vacuum leaks. He currently has about 600 miles on it so as soon as he gets 1000 miles he'll bring it in. I'll report back then.

RACNRAY

[ponch]

Originally Posted by RACNRAY

I spoke to a forum member yesterday that had seen this thread when I first posted it and had disasembled his Vulcan Classic and found a few interesting things.

First his posts were taller than mine by about .006". The sealing surface on the intake manifold was warped by about .010", and the o-rings that seal the manifold to the intake ports had small tears in them.

He has a friend that owns a machine shop, so he had the throttle body machined flat and block sanded the intake surface flat. He had put it all back together with new o-rings quite some time ago but the weather and road conditions where he lives prevented him from riding his skoot, till yesterday.

His findings were the acceleration was very much improved, the backfire on decel was reduced about 50%, and he had a hesitation since new, even after his ECU was replaced that is now completely gone.

I experienced the same improvements so from what i see here the occurance of some percentage of vacuum leaks may be plaguing Vulcan owners.

I have a customer that just bought a Vaquero, he has some strange things happening with it's low speed running, so after he has the skoot broken in it'll be here for dyno work and to check him for vacuum leaks. He currently has about 600 miles on it so as soon as he gets 1000 miles he'll bring it in. I'll report back then.

RACNRAY

And Mucker had no issues with his throttle body when he disassembled his 1700 engine: http://forums.delphiforums.com/kawvu...msg=105848.143

It's a good thread and shows how well the 1700 engine is engineered. Mucker did this to put the revised gearing and piston rings in his 1700. The Mucker is a motorcycle mechanic by trade.

[RACNRAY]

Originally Posted by ponch

And Mucker had no issues with his throttle body when he disassembled his 1700 engine: http://forums.delphiforums.com/kawvu...msg=105848.143

It's a good thread and shows how well the 1700 engine is engineered. Mucker did this to put the revised gearing and piston rings in his 1700. The Mucker is a motorcycle mechanic by trade.

GOOD FOR HIM!! Thanx for letting us know his is ok.

So far there are 3 of us that found intake leaks, the guy that alerted us to this many months ago, he did his own testing and i am grateful he pursued disassembly of his skoot, mine and Tims. I don't know how many more is out there, but when Chris brings in his V I'll see if his is suffering from this problem.

RACNRAY

[brote]

No doubt in my mind moving the MAT / IAT will fatten up the mixture. Cold air is more dense and can use more gas. If we had a closed loop system, once the system went into closed loop the O2 sensor would handle the mixture trying to keep it at 14.7:1. I also believe that getting your TPS set correctly is very important . Now I wouldn't just run a specific resistor to replace the IAT but moving it works. Just my thinking, which may be faulty.

[ponch]

Originally Posted by brote

No doubt in my mind moving the MAT / IAT will fatten up the mixture. Cold air is more dense and can use more gas. If we had a closed loop system, once the system went into closed loop the O2 sensor would handle the mixture. I also believe that getting your TPS set correctly. Just my thinking, which may be faulty.

There are a lot of benefits to a closed loop system, like running on a lower grade of gas if necessary and better adaptability to changes. Considering Kawasaki has it on other models, they could build a cruiser with one.

[jp58]

Originally Posted by ponch

There are a lot of benefits to a closed loop system, like running on a lower grade of gas if necessary and better adaptability to changes. Considering Kawasaki has it on other models, they could build a cruiser with one.

From what i've read all the 1700's have an 02 sensor (closed loop) that are built for California. I read it in my owners manual somewhere.

[ponch]

Originally Posted by jp58

From what i've read all the 1700's have an 02 sensor (closed loop) that are built for California. I read it in my owners manual somewhere.

Probably so. BMW's are 50 state bikes and they have closed loop. That's a good thing if I wanted to move to CA. I heard if you have a 49 state vehicle, it sucks if you move to CA.

[RACNRAY]

This is the post from the member that tackled diagnosing his intake concerns (posted dec 2011)

QUOTE
"I checked my 1700 classic for intake leaks after seeing what Ray posted about his bike. The way he described how his bike was running sounded like how mine began to run. I found intake leaks between the throttle body and the intake as well as where the intake met the heads. I took it apart to find the same thing as his. The stand-offs on my throttle body were 14 thou tall where his were only 8 thou tall. And as though that wasnt enough, my intake manifold was warped 10 thou on both outside edges of the intake ports and the o-rings where the intake met the heads had small tears and chunks of the outer layer of rubber was missing. My friend has a machine shop so after removing the 14 thou stand-offs off we found the throttle body to still be 4 thou warped in the center. We machined the throttle body surface and trued up the intake by lots of wet sanding on a perfectly flat surface because there isnt a good way to mount it in a mill . I got it back together last night and on initial start up the engine seems much more stable. it comes off of high idle much faster and idles much smoother. The throttle seems much more crisp as well. The real test will be getting it out on the road but i woke up to snow this morning so i guess i will have to wait."
END QUOTE

I just spoke with him and he finally had the first chance the other day to ride his skoot. The results as he reported are a 50% reduction in decel popping, much better throttle response and the complete elimination of a hesitation he has had since new, even after the recall ECU was installed. He sounded very excited, he will post as soon as he can but this is just a brief description.

RACNRAY

[RACNRAY]

I now have close to 6000 more miles since the intake fix and the skoot is runnin flawlessly.
Since the map that was in the PCV was the map that was made during the last dyno session and there had to have been some small percentage of vacuum leaks at that time, i ended up having to lean out my idle and the lower throttle percentage/rpm rows as those are areas that were most affected by the vacuum leaks, the skoot was even happier after that.

There have been concerns about why the posts on the t/b's are there. Sticking with the "heat transfer" theory, reducing heat in the t/b assembly may have to do with lowering the operating temp of the servo motor which controls the butterflies. This is an electric motor device so it makes sense that we would want it to have the lowest temp for longevity. Besides the airbox the t/b is the part of the intake system that sits the furthest away from the heat of the engine. If the reduction of heat transfer is why the posts are there, then that consideration in design and manufacure has also compromised a good seal between the t/b and intake manifold. The amount of 0-ring compression on my skoot was nowhere as much as i see on other skoots that utilize an o-ring for sealing. When Mark bolted down my t/b he could, by "feel", sense the amount of o-ring compression was similar to what we feel is the norm. We find vacuum leaks are a problem, specially on bikes older than 5 years, as the o-rings (or the rubber lip molded onto the manifold) flatten out over time, allowing leaks. Most manifolds develop a "warp' in them and are no longer flat, needing surface correction.

I try not to overthink things, my experience in working on Jap skoots for over 35 years has allowed me to kinda "learn" their way of thinking.

Back in 1976 Kawi issued a "factory directed modification" on the KZ400's. They had a defective design in top end gaskets and o-rings that had some of those skoots leaking oil real bad. The replacement gasket kit was real neat in that it had new style gaskets and o-rings that replaced the original stuff. I did many of these kits and never had an oil leak after that. It did take Kawi about a year to come out with this FDM.

The HUGE tolearnces allowed in mass production has many affects on many aspects of our skoots. My dyno has proven that time and again. Being able to dyno stock bikes of the same model i have seen HUGE differences in power. Example: the 1999-2007 Hayabusa's average around 150-152 H.P., with 2 or 3 up around 157-158, and a couple down at 146-147! A 12 H.P. spread! Think of the THOUSANDS of machining operations it takes to make an engine! We do alot of cylinder head porting/polishing and i have seen, just in heads i have had apart, noticeable variations from head to head. I am currently doing a 2009 R1 head, and it's interesting to see how the ports match the valve seats on the #1 cylinder pretty good, but the match of port to seat gets worse on cyl's 2,3&4 being the worse!

I am waiting on Chris to finish the break-in on his Vaquero so we can document his power (and compare it to mine) and since he is having some funky running characteristics i wonder about vacuum leaks on his skoot. We shall see.

RACNRAY

[RACNRAY]

Thi is the post detailing the results/improvements after the intake leaks on his Vulcan were fixed.

"I finally got to ride my bike after i got home from work. What i have found is the overall smoothness of how the engine runs, idles, is better than the day i bought the bike. My decel popping has decreased by atleast 50 percent and im sure a good fuel processor will take care of the rest. Im not really thrilled with mt FI2000 due to lack of tuneability. The throttle response is very crisp compared to the way it was before. The bike also had what i refer to as a cough from the day i bought it. I had the ECM replaced under recall and in my opinion it actually ran worse than before i had it changed. The "cough" would happen at any given time when rolling on the throttle and would basicly pop back through the intake. From what i can tell by riding it the other day is its now gone after i made the repairs. The bike runs great. I didnt want to believe that my brand new bike had a vaccum leak but i definitely did after some simple testing. Anyone experiencing decreasing perfomance, poor idle quality, excessive decel popping backfing, i would recommend looking for vaccume leaks because they may be there just like Racnray and myself both have found. Its only a matter of time before more and more of these start showing up."

His performance/driveability improvements mirror mine. I know of a few other members that are planning to check their skoots for vacuum leaks, so we'll wait to hear their results.

RACNRAY

[element80]

Originally Posted by RACNRAY

Thi is the post detailing the results/improvements after the intake leaks on his Vulcan were fixed.

"I finally got to ride my bike after i got home from work. What i have found is the overall smoothness of how the engine runs, idles, is better than the day i bought the bike. My decel popping has decreased by atleast 50 percent and im sure a good fuel processor will take care of the rest. Im not really thrilled with mt FI2000 due to lack of tuneability. The throttle response is very crisp compared to the way it was before. The bike also had what i refer to as a cough from the day i bought it. I had the ECM replaced under recall and in my opinion it actually ran worse than before i had it changed. The "cough" would happen at any given time when rolling on the throttle and would basicly pop back through the intake. From what i can tell by riding it the other day is its now gone after i made the repairs. The bike runs great. I didnt want to believe that my brand new bike had a vaccum leak but i definitely did after some simple testing. Anyone experiencing decreasing perfomance, poor idle quality, excessive decel popping backfing, i would recommend looking for vaccume leaks because they may be there just like Racnray and myself both have found. Its only a matter of time before more and more of these start showing up."

His performance/driveability improvements mirror mine. I know of a few other members that are planning to check their skoots for vacuum leaks, so we'll wait to hear their results.

RACNRAY

Isn't this something Kawi should fix?

[RACNRAY]

Originally Posted by element80

Isn't this something Kawi should fix?

YES!! Now that some of us have diagnosed intake leaks on our skoots, performed the necessary repairs and achieved performance improvements, somehow this info has to make it to Kawi, to actually someone there who gives a you know what to even start the process of Kawi investigating.

Back when i was a service (circus!!??) manager at a Kawi dealer we recieved factory directed modifications from Kawi for skoots that had certain problems. This issue would fall under the FDM as i have heard some peeps don't have vacuum leaks on their skoots.

Anyone with a running/performance issue should take this info to their dealer and have their skoot checked out. Hopefully this will help.

RACNRAY

[ponch]

Originally Posted by element80

Isn't this something Kawi should fix?

Only if they think it's enough of a problem. Unless it's a safety issue, manufacturers may play dumb and not acknowledge an issue. The question I have is, why is it a problem for some and not others? Is it design, manufacturing, environmental, idiopathic, psycho-autobirotaric or a combination? BMW has had issues with final drives for 10+ years. Only last month did the NHTSA open a case in spite of the complaints. Some estimate the failure rate for some models/years to be 4%. That's bad. Funny thing is, they made changes to the final drives over the years and the problem seems to have gone away. Back to Kawasaki, look up POG. Hopefully, if there is a real issue, they will address it.

[RACNRAY]

From what i have learned in the short time i have owned my Vaquero and been involved on a few Vulcan forums, i believe performance issues go back to the 2009 model and from what i have read, many peeps having stalling/poor running/ excessive popping on decel.

Kawi's original and current fix was to install under warrantee "upgraded?" ECU's that many commented not only did not cure whatever their particular complaint was, but fuel mileage suffered and some commented their skoots ran WORSE. Kawi has been throwing ecu's at a problem that has the source of it's affect elsewhere.

This is a very real problem on some but maybe not all skoots. As a 35+ year m/c mechanic I see the affect of mass production on a daily basis many times. There are so many allowable tolerances in the manufacture of all the components it takes to make one engine, that is a by-product of mass production. I read in a thread that the compression ratio on a torn down Vulcan was .4 LOWER than what Kawi specified, and that can only come from allowable variations in mass production.

As a dyno owner operator since 1993 i have ammassed over ONE HUNDRED THOUSAND dyno runs on various skoots, and one thing we do is dyno every single stock skoot b4 ANYTHING is done. The variances in power are sometimes HUGE and disappointing for an owner of a weak example. Case in point, the first generation Busa's have a peak power spread from 146 to 158, 12 H.P. on completely stock skoots! That's what they're building and that's what we get.

I should be recieving the intake system from an owner of a Vulcan that diagnosed intake leaks on his V tomorrow for our mod. I'll be able to take measurements, compare them to mine and have another example of mass production variations.

I'll post the results.

RACNRAY