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How come when you start bike and put in first gear you get the clunk? But, while still holding clutch in, put back into neutral, let clutch out, pull clutch back, put into first gear again, but this time no clunk? Mine,2010 FatBoy, does this every time.
So is it the trans clunking? Or is it the compensator taking up slop first time after shut down?
wilks3

Do you REALLY want to know why. If so, here it is in all it's Glory......

The reason why that happens is because of Inertia. Heavy objects once in motion want to remain in motion. (or at least remain in motion until Friction slows them down). Understand that point, and you will understand the reason for the "clank"..

Lets look at the entire drive train as follows. The transmission is just a box that has an input shaft and an output shaft. The input shaft is attached to the engine side but can be detached from the engine via the clutch. The output shaft of the transmission box is directly attached to the rear wheel. The input & output shaft from the transmission are directly coupled to each other EXCEPT when in neutral. (1st Key Point!)

The Clutch also has an Input shaft & an output shaft that is directly coupled to each other EXCEPT when the clutch lever is pulled IN. (2nd Key Point!)

So mentally look at the drive train as follows.. ENGINE=>CLUTCH INPUT=> CLUTCH OUTPUT=>TRANS INPUT=>TRANS OUTPUT=>REAR WHEEL.

** Once again Remember that TRANS INPUT =>TRANS OUTPUT can only be broken (or uncoupled) when the gearbox is in neutral.

** Once again remember that gears & metal parts have inertia and once in motion want to remain in motion.

** For discussion purposes only when it is said that your clutch LEVER is OUT (or released), it means the clutch input shaft and output shaft are DIRECTLY coupled to each other.

So if your still with me up to this point, the rest is easy...Here we go.

Your bike is in neutral,, and your clutch lever is out and you start your engine. At this point the engine is turning,, the clutch input & output shafts are turning and the Trans input shaft is turning. Since the trans is in neutral, Trans output shaft is not turning.
You now pull the clutch lever in. Since the Trans input shaft and gears have inertia, they continue to spin even though the clutch input to output shafts are no longer directly coupled to each other. Since the Trans input shaft is spinning and the out is standing still, you hear a loud clank when those two shafts engage from your foot placing the gearbox in 1st gear.

Now lets do it again, but this time you wait a bit.

Your bike is in neutral,,and your clutch lever is out and you start your engine. At this point the engine is turning,, the clutch input & output shafts are turning and the Trans input shaft is turning. Since trans is in neutral, Trans output shaft is not turning.
You pull the clutch lever in BUT THIS TIME YOU WAIT a bit. The turning Trans input shaft has time to slow down and loose it's inertia. The input shaft of the Trans slows down and maybe even stops. Now the Trans input and Output shafts are BOTH STOPPED. Now when you shift into 1st gear, there is "less clank" because you not engaging a moving part with a stationary part.

Note: (There are also other parts of the process which need to be mentioned but not discussed. One is parasitic drag of a wet clutch. Even though a wet clutch may be dis-engaged, the output shaft will continue to spin due to parasitic drag of the oil or fluid. Another issue is sticking of clutch friction plates and the 1st time they need to "Break Free" from each other from sitting in a compressed state while not being used. But for the most part, all the above holds true)

Still awake?:p
 
Hoop, I understand what your saying........but, I never shut off engine.
Start engine trans in neutral, let run about 20 sec, pull in clutch, wait about 20 sec, clunk as trans goes into first. Put trans into neutral, let out clutch, wait about 20 sec, pull in clutch, trans will go into first with no clunk. Everytime, hot or cold.
The only difference is the compensator didn't unload (?) when engine shut off.
Your thoughts please
wilks3
 
Some may gasp at this but I ran mobile 1 for v-twin 20/50 in the tranny for a while after reading some info saying the the rating for gear oil viscosity was the same or similar to the 20/50 oil while the numbers meant different things (I don't remember exactly what the article said) and it seamed to perform as well as the spectro does (which I'm running now after learning about it) the clunk is the same and the 5th gear whine was never a problem. Has anyone else share the same experience?
 
Do you REALLY want to know why. If so, here it is in all it's Glory......

The reason why that happens is because of Inertia. Heavy objects once in motion want to remain in motion. (or at least remain in motion until Friction slows them down). Understand that point, and you will understand the reason for the "clank"..

Lets look at the entire drive train as follows. The transmission is just a box that has an input shaft and an output shaft. The input shaft is attached to the engine side but can be detached from the engine via the clutch. The output shaft of the transmission box is directly attached to the rear wheel. The input & output shaft from the transmission are directly coupled to each other EXCEPT when in neutral. (1st Key Point!)

The Clutch also has an Input shaft & an output shaft that is directly coupled to each other EXCEPT when the clutch lever is pulled IN. (2nd Key Point!)

So mentally look at the drive train as follows.. ENGINE=>CLUTCH INPUT=> CLUTCH OUTPUT=>TRANS INPUT=>TRANS OUTPUT=>REAR WHEEL.

** Once again Remember that TRANS INPUT =>TRANS OUTPUT can only be broken (or uncoupled) when the gearbox is in neutral.

** Once again remember that gears & metal parts have inertia and once in motion want to remain in motion.

** For discussion purposes only when it is said that your clutch LEVER is OUT (or released), it means the clutch input shaft and output shaft are DIRECTLY coupled to each other.

So if your still with me up to this point, the rest is easy...Here we go.

Your bike is in neutral,, and your clutch lever is out and you start your engine. At this point the engine is turning,, the clutch input & output shafts are turning and the Trans input shaft is turning. Since the trans is in neutral, Trans output shaft is not turning.
You now pull the clutch lever in. Since the Trans input shaft and gears have inertia, they continue to spin even though the clutch input to output shafts are no longer directly coupled to each other. Since the Trans input shaft is spinning and the out is standing still, you hear a loud clank when those two shafts engage from your foot placing the gearbox in 1st gear.

Now lets do it again, but this time you wait a bit.

Your bike is in neutral,,and your clutch lever is out and you start your engine. At this point the engine is turning,, the clutch input & output shafts are turning and the Trans input shaft is turning. Since trans is in neutral, Trans output shaft is not turning.
You pull the clutch lever in BUT THIS TIME YOU WAIT a bit. The turning Trans input shaft has time to slow down and loose it's inertia. The input shaft of the Trans slows down and maybe even stops. Now the Trans input and Output shafts are BOTH STOPPED. Now when you shift into 1st gear, there is "less clank" because you not engaging a moving part with a stationary part.

Note: (There are also other parts of the process which need to be mentioned but not discussed. One is parasitic drag of a wet clutch. Even though a wet clutch may be dis-engaged, the output shaft will continue to spin due to parasitic drag of the oil or fluid. Another issue is sticking of clutch friction plates and the 1st time they need to "Break Free" from each other from sitting in a compressed state while not being used. But for the most part, all the above holds true)

Still awake?:p
Nice Hoop. :newsmile106:

Enjoy,
Rich P
 
Hoop, I understand what your saying........but, I never shut off engine.
Start engine trans in neutral, let run about 20 sec, pull in clutch, wait about 20 sec, clunk as trans goes into first. Put trans into neutral, let out clutch, wait about 20 sec, pull in clutch, trans will go into first with no clunk. Everytime, hot or cold.
The only difference is the compensator didn't unload (?) when engine shut off.
Your thoughts please
wilks3

I bet this is what's happening. See the "note" at the end of original post above. When an oil clutch pack disc set sits for a time, they will stick together and won't separate for the FIRST TIME YOU USE THEM. After that 1st "unstick" time,,,your usually good to go.

It is very similar to the effect of taking a glass window pane, and placing a few drops of water or oil on it and placing another pane of glass on top and pressing them together. There is a fancy word for it that I can not recall, but the two pieces of glass will stick together and it would take a bunch of force to rotate or pull them apart.

So back to your question/problem. This is what I believe is happening. Lets break down what you are saying into two parts. Part #1 "Start engine trans in neutral, let run about 20 sec, pull in clutch, wait about 20 sec, clunk as trans goes into first." That is exactly what I would expect to happen. (happens to me also) When you pull in the clutch lever,, the clutch pack is still is revolving "as one" because the pack is not separated yet,,. it is stuck together like the panes of glass. Then when the dogs in the transmission engage, a loud clank is heard. That is the moment when the pack breaks loose.
From this point ON, the pack is broken,,, therefore part#2 makes sense also => Part #2. "Put trans into neutral, let out clutch, wait about 20 sec, pull in clutch, trans will go into first with no clunk. Everytime, hot or cold"

Want to prove if this is what is happening? Try this. When you put your bike away for the night, Tie wrap the clutch lever to the bars. Let it stay overnite with the lever pulled ALL THE WAY TO THE BARS. This should prevent the clutch pack from becoming one and "seting up". When you start it in the morning, STILL WAIT the 20 seconds and foot lever the bike into 1st. My guess is it will be quiet.
 
So like a fool I have been listening to the Harley and running formula + in my trany. Did my 20K service and drained my tany and found there was just an insane amount of metal shavings on my magnetic plug so that junk will not be going back in my trany and the bottle I bought went on the shelf for the next time I do my primary and i went and bought a bottle redline shock proof. We will see how well the redline does.


Dave

I just got my 07' FLHTC back from the dealer. They had been puttin Syn3 in it since new. Guess what, bang! If your experiencing excessive vibration, particularly in sixth gear, get it looked at. Thats how mine started. Followed by excessive gear lash. Now, all new bearings. As far as the Red Line, you should notice a difference by the end of the driveway. I'll never put anything else in mine again.
 
How come when you start bike and put in first gear you get the clunk? But, while still holding clutch in, put back into neutral, let clutch out, pull clutch back, put into first gear again, but this time no clunk? Mine,2010 FatBoy, does this every time.
So is it the trans clunking? Or is it the compensator taking up slop first time after shut down?
wilks3

Quite simply...the clutch pak discs and plates stick by cold oil surface tension. If you, shift into neutral, pull in the clutch lever, start the engine, the vibration and tension removal allows the surface tension to give way allowing the clutch pak discs and plates to separate...if you hold it in for 3 to 5 seconds AND roll the bike forward or back, you will actually feel the bike moves with less drag and it frees them even more. So there is only a mild clunk when you put it in first gear. You will definitely hear and feel the difference. I have a Sportster, with plain Spectrol Gold, (recently changed to 85-140 Gear oil) in the clutch/primary combined hole and it took me only a few starts and shifts using this sequence that convinced my that mild clunk is better than that "bang" or clank...:rofl
 
In the old days when i only had a kick start on my 75 bonnie then part of the starting procedure on first start of the day was to pull in the clutch lever and and do a full swing on the kick starter twice this was to free off the clutch plates prior to starting
on modern bikes to achieve the same prior to starting put bike in gear and pull in on clutch lever and rock bike back and fourth till you feel the clutch come free
or hold in the clutch lever for about 30 sec after start before selecting gear this procedure works for me i do have the clutch correctly adjusted the primary oil at the correct level and am using formula+ in the primary
using a thicker oil or having too much in the primary may give a little more drag on the clutch for that first gear selection

Brian
 
So put 3k miles on the bike after switching to the redline shock proof and changed it today. Zero metal on the mag tip this time wish I would have took pics of the mag tip with the formula+ so i could post the diffrance. I cant say I fell a big diff in the way it shifts but it is nice to have no metal on the plug just hope the damge already done isnt to bad.


Dave
 
So put 3k miles on the bike after switching to the redline shock proof and changed it today. Zero metal on the mag tip this time wish I would have took pics of the mag tip with the formula+ so i could post the diffrance. I cant say I fell a big diff in the way it shifts but it is nice to have no metal on the plug just hope the damge already done isnt to bad.
Dave

Thanks for posting that Dave... It just takes Some :small3d023: Longer to find this out.

I have always said NEVER-EVER any metal on the magnetic plug when using Redline Heavy Shockproof.(.)

Good Stuff!
signed....BUBBIE
 
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