top end engine tap
- Thread starter mike wallace
- Start date
mike wallace
Member
What video by Matt and tube in tank? Also what is the imfamous suckandator? I am slow
TapioK
Well-Known Member
Post #31, Matt (almost) went crazy trying to find a source for sewing machine like noice...
Search ZenBD "unfathomable noise" it is sometimes pretty hard to tell from where the noise originates.
Suckendator is a myth, bit like a honest politician, but according to a legend it can cause all kinds of strange problems in our bikes and wildest rumors tell it can actually spread it's poison to ppl closest to us resulting Mad Cow Disease like symptoms on some spouses!
Tapio
Search ZenBD "unfathomable noise" it is sometimes pretty hard to tell from where the noise originates.
Suckendator is a myth, bit like a honest politician, but according to a legend it can cause all kinds of strange problems in our bikes and wildest rumors tell it can actually spread it's poison to ppl closest to us resulting Mad Cow Disease like symptoms on some spouses!
Tapio
john sachs
Well-Known Member
Why would you piss money away on another set of adjustable p/rods ? If your original ones were adjusted properly(a bent one would show up by the way), they ARE NOT the problem. More than likely damage has started from the TP boxes on a S&S engine. Changing the rocker boxes IF damage has started won't fix the problem, just like wearing a condom after being aids infected won't further prevent the disease to yourself.
John
mike wallace
Member
Good point, can I just put s@s rocker boxes without many other changes or do I need to just go with the TP rocker box. What should I expect to have them done?
TapioK
Well-Known Member
Would you do a search on the site, you would find a lot of discussion about this. John does know his shit...
Tapio
SMCT
Active Member
I want to mention this, or shed some light on something. I as well had a noise at the rocker box. I had gone through just about all that you can go through and didn't find a thing. To accept the fact from many "that this is normal" just didn't sit well with me. I build race engines for a living and a rocker noise, or a noise from the rocker box or valve cover is not normal. I figure that during the winter, I will just change out parts because I didn't physically see anything. As time went on, I dealt with other issues and one of those issues was the popping during de-accel with the throttle blade on the carb closed. I made baffles for the exhaust in my shop, and installed them. The baffles actually cured that rocker box noise. I didn't make them to cure the box noise, but it did. In building engines for a living, apparently what was occurring was combustion that was not completely in the chamber and apparently a portion of combustion was occurring in the primary pipe most closest to the head. The back pressure from the home made baffles kept the combustibles (fuel and air) in the chamber and didn't let a portion get out into the primary to ignite.
If I pull the baffles out, the noise will be back in the rocker box.
If I pull the baffles out, the noise will be back in the rocker box.
john sachs
Well-Known Member
Seems to me that a proper tune, and an exhaust system that's not leaking would have fixed the popping problem.
You're right though, most engine noise is NOT normal. Especially when there's a valve train geometry problem which you have with the TP boxes on S&S heads.
John
Glad to see the forum cops on the prowl. Nicely done.But I'll tell you even more than that. On our forum have a secret ... We all do the intro ... After that the bike was repaired ...
mike wallace
Member
I have been reading a lot of the threads, is the consensus that I should put S&S rockers on the s&s heads.
TapioK
Well-Known Member
Well, some have had problems with low mileage, some with high, some have had no problems. It seems to be a bad combo in general. Would I now buy one more Dog, I would look hard for S&S boxes or at least take account the price of the fix in my offer... But that's just my opinion. Viking has TP with no problem, then again sounds like you have...
Tapio
Tapio
mike wallace
Member
Again like original text, sounds like sewing machine on top end front of engine. Took to my mechanic and checked rockers, valves, pushrods and said all had wear but looked fine and no need to replace any. Also did pressure bleed down and everything was fine. One option is to take the new mechanic but I trust this mechanic so I'm not really sure where to go from here .
TapioK
Well-Known Member
Well, if everything is adjusted correct, all the parts good and fine, your mechanic is good, you both are sure the noise comes from top end and not say mentioned rattle tube inside the tank, that leaves only one place to go, bar to get a beer I suppose.
That is if you don't want to throw in some money and go for S&S anyway. John Sachs has talked abut the problem a few times. He is the man who knows what he talks about.
Tapio
That is if you don't want to throw in some money and go for S&S anyway. John Sachs has talked abut the problem a few times. He is the man who knows what he talks about.
Tapio
john sachs
Well-Known Member
I had 2 TP rocker boxed on S&S engine Dogs come in last year for builds. Customers said they were running good. This is what I found. The other one wasn't quite as bad, but it still was close. Valve seating in the aluminum beyond the seat insert. Half of the valve guide was worn razor blade thin.
Unless you check valve stem to guide clearance, you'll never know.
John
Attachments
hellcat5864
Member
Had a buddy with almost the same issue , turns out the compression relief valves were the issue on his 117 s&s motor
Sent from my iPhone using Tapatalk
Sent from my iPhone using Tapatalk
john sachs
Well-Known Member
I did, and that's why I mentioned that most popping noise on decel comes from a leaking exhaust system or improper tune.
As you said, "working on your exhaust system fixed your popping noise".
John
mike wallace
Member
Ok John so I took my 05 mastiff to new mechanic that said he had worked on several big dogs. He agreed with you that the valve guides are shoot and I need new rocker boxes and that the heads really need to be shaved down to perform the way they should. he said that big dog and TP rockers had an issue with geometry and that they do not ride or seat correctly. He said to repair correctly I am looking at 5-6k. Then he suggested just putting in another engine at about 7k so I would have a warranty. He said the last option was to sell and buy an HD, so that made me feel he may not want to do work. I was wondering if these numbers sound accurate, I love the ride and look of my bike.
Big Dog Mastiff
Steve
Mien has always sounded like a sewing machine, so I went with a louder exhaust!