First off I should point out I'm not posting this to debate, but just to offera solution I found to solve MYtrans chatter problem with my 07 Road King with a June 06 build date. This may or may not help you but I hopesome will benefit from this.

Anyways my take on the trans chatter problem isthe comp sprocket or primary chain while doing its job is causing a chatter noise. The chatter noise is asymptom or the real problem which is the motor NOT running smooth when under light load below2500. Instead of trying to eliminate the symptom I focused on the source of the problem and tried to get the motor to run smoother at the lower RPMs.

My Road King has a SE 203 Cams, Big Sucker and Slip on D&D. It ran very smooth at 3000rpm + and fairly smooth at 2500-3000. But anything under 2500 in 5th or 6th gear and the bike sounded like it was going to drop the bottom end out.

1) Tried going through dealer. No help as you all already know.

2) Keep RPMs above 2500 and never used 6th gear unless going 70mph. This worked, but I hate having to down shift every time I need to slow down5mph just to make a curve. 96" motor should be able to LUG.

3) Installed SERT, CAMS, A/C and Mufflers withmap #78 form Disk H. Not much improvement for trans chatter but bike runs great. I started data logging at this point and Trans Chatterand Knock retard go hand in hand.

4) Installed map #78 from the J disk. This was an improvement but still some chatter.

5) Added Fuel via the CBL and Removed 7 degrees timing in the "Chatter Zone" over severaldata log runs. Removing timingby farhas the biggest impact on how smooth themotor runs. Side benefit istrans chatter is now non-existent. Ona side note MAXing the CBLs does not work on my bike. It causes it to, runtoo rich,blow black smoke,lazy accelleration and pop on decell. Setting them600-750mv range has worked best for me.....Might be due to the cams


Note how the timing (pink line) jumps all over due to the knock retard (Black Line) pulling up to 7 degrees timing yetMAP and vehicle speed are steady.You can clearly see whenI back off the throttle (MAP decreased), Knock retard (and Trans Chatter are eliminated).

My lastest data logs after removing timing. Show no knock retard timingandtrans noise is gone. Take this info with a grain of salt and use as you will...........over and out.




Data Log with BASE MAP #78 off the H disk
[IMG]local://upfiles/19340/5BA1DBB0C03F41A59DF89423D770EA20.jpg[/IMG]

 

cj

You have me kinda confused on the description of "chatter" and what you are referring this noise to.You make mention of the comp sprocket and primary chain and then refer this to transmission chatter.............I'm a wee bit confused.

The "chatter" that I refer too is strictly a noise coming from the primary between 68-72mph in 6th gear usually going downhill.....kinda like the chain and/or comp sprocket is responsible for this noise slapping around inside and not the transmission.

I refer to the transmission sound as a whine........which doesn't bother me at all.

could you clarify please. I BELIEVE we areon the same page, but I could be mistaken. I seek clarification so I can pass this on to my tuner and maybe get the "chatter" out of the rangeI have described on my bike.

Thanks.

 

My noise is the same as yours only at a slightly slower speed.Can't say for sure where its coming from and don't really care as I believe its a syptom not the root cause. I only refered to it as Trans chatter as that seems to be what most call it. If I had to guess I would say its morein the primary drive system, Comp sproket, chain tensioner,Primary chain ora combination of any of the above. I can't ruleout anything in the trans though and Baker Drive Train makes some good auguements.

IMHO:Get the motor to run smooth in all areas and your Chatter (where ever its comming from) will be reduced or eliminated. HD called the 903a"Torque Smoothing Download"......just need to read between the lines and go one step farther to eliminate all knock retard.

Anyone disable Knock retardtosee what happens??

 

I follow what you are saying now. thanks.

I am REALLY interested in becoming more familiar with mySERT. I am certainly interested in eliminating the "chatter" and find it interestinghow removing timing in this area hasdone the trick for you. I just wish I was close to someone that had a clue about all this that could explain cause and effect on manipulating these variables instead of via the internet.

 

CJ
Great post, I have a power commander 3. Do you know if these changes can be made with the Power commander or will I need to go for the SERT. I also would need to find someone that had a clue how to make the changes

 

I've never used a power commander, but from what I've read you should be ableto adjust timing, but I don't think you can monitor or disable the knock sensors. Make several small steps of 1.5 - 2 degrees changes in a small area andride for a day or two whilelooking for"Better, Same Worse". Then move to the next.If you can graphyour Ignition table blend in any large dips or spikes as you go.

If your bike is runninggood no need to make major.Take you time and monitor over several rides while making small changes.

 

The PCIII has an ignition-timing table that can be altered in the same fashion as the A/F ratio, which is relative to throttle position and RPM's. What would worry me about reducing ignition timing is increased heat and decreased mileage, as the clatter rears its head in the cruise range. In my case, clatter is heard below about 2300 RPM's at low TP's (<10%). I have the 0903 flash and PCIII with map from Fuel Moto that I've tweaked for better mileage (leaner in the cruise range). I couldn't be happier with the bike's performance, and I'm realizing 50 MPG on rides where there are few cold starts--i.e., at normal operating temperatures. I have not figured out a way to improve mileage while the bike is warming up, but I'm working on it.

After reading your post, I might try retarding ignition timing around 2000-2250 RPM's and see what happens, but I'm not sure how much you retarded it. My approach to the clatter is to use higher-viscosity oil, specifically 20w50 fossil engine oil in the primary (minor improvement) and 85w140 gear oil in the tranny (major improvement). I now have clatter eliminated in 6th gear and reduced in 5th. The whine is still there, but like you I find it innocuous.

Did I read correctly that you retarded ignition timing 7° in the "clatter range"? Since I'm never intentionally below 2k RPM with this engine, I assume you mean 2000-2300. Is that right? The 0903 "torque-smoothing" flash purportedly retarded timing in critical places, so how do I know it hasn't already been implemented with my EFI (not PCIII) map? My PCIII ignition-timing for my map shows no changes below 40% throttle, which is above the clatter zone, and is zeroed out everywhere else. This means it's at stock settings in the clatter zone.

Also, please define "CBL," as that doesn't compute in the PCIII world, or at least I'm not aware of it.

 

Unfortunate your question bring up are the reasons I picked SERT over the PCIII, but I'll take a stab at it.

The PCIII has an ignition-timing table that can be altered in the same fashion as the A/F ratio, which is relative to throttle position and RPM's. What would worry me about reducing ignition timing is increased heat and decreased mileage, as the clatter rears its head in the cruise range.

With SERT you adjust timing in .25 degree increments from TDC. The Base map I used had timing 26-42 degrees in the rpm range of 2000- 2500with a MAP of 60 or less. Even afterremoving 7 degrees there is still plenty of timing left.I have no intentions of cruising under 2500rpm, just want the bike to be able to pull through for an occasion curve or whatever without down shifting. With the PCIII, I believe youadd or subtract from the current stock ECM value which is unknown to the end user.


I have not figured out a way to improve mileage while the bike is warming up, but I'm working on it.

Not sure with PCIII, but with SERT you could try adjusting the "Warmup Enrichment Table" and the "Cranking Fuel Table"


Also, please define "CBL," as that doesn't compute in the PCIII world, or at least I'm not aware of it.

CBL = Closed Loop Bias: This is the voltage from the O2 sensorwhich the ECM uses to determine if the system is running rich or lean. By changing this setting you can change the AFR while in CLOSED LOOPbetween 14.2 - 15.2. The PCIII eliminates the O2 sensors, so this function along with Closed Loop operationhavebeen eliminated.

Not Trying to bash the PCIII.....I know some bought them before any real info on SERT was available or had one from a previous bike. But here's a situation where the advantages of SERT easily offset the add cost IHMO.By no means am I saying everyone should switch to SERT, but if you own an 07 and areon the fence with what you should buy AND and fall inthe DIY catagory. I would recommend the SERT.

 

The new thundermaxfrom zippers claim they have no knock retard or knock sensors in their system. They also claim their ecm system willlet the engine run very smoothlyeven in the low rpmproblem areas "as low as 1700 rpm" without any lugging sounds.
Wonder if this is so??

 

The ECM timing is unknown, as you say, but it might be productive to do some experimenting in the 2000-2250 and 5-10% TP "clatter zone."

PCIII won't adjust this table, but the cost moving to SERT wouldn't be productive for the gas savings realized. I'm not even sure what the result would be, as it might be that any change toward leaning the mixture would produce unacceptable performance.

Seems like it should be "CLB" instead of "CBL." Anyway, that's okay, as the A/F ratio can be altered effectively without the O² sensors. I've achieved excellent mileage (~50 mpg) , an acceptable heat level, and excellent performance by tweaking the PCIII.

May be, but after the initial SW and HW cost with a dyno tune, it would be a much more expensive proposition. After that, I assume SERT can be tweaked using a notebook computer just as the PCIII can. Although I'm happy with the performance of my PCIII thus far, if I had to do it again I would do more research in consideration of the SERT and ThunderMax. At the time I bought mine (last Nov.) the majority seemed to be recommending the PCIII. Nowadays there are problems with "delayed start" and hesitation, although neither are a problem for me. The "delayed start" means the difference of instantaneous starting and a one-second delay as the PCIII reboots.