Noise from open primary

[Staffy]

I'm lost and confused - and need your help and input, please.

07 K9 with Karata 4" open primary. (The OBS has been removed when taking this video).

When the bike is started and in "idle" there is a "rattle" when you pull in the clutch lever the noise mysteriously disappears. (The noise is also not noticeable at high engine revs and speeds)

Any ideas folks? Could the noise be coming from the tranny?

(I will be dissembling the primary in order to replace the engine seal but will get to that after some feedback, just in case I need to test stuff while the bike is assembled and running)

(Although not mentioned in the commentary – during the video the clutch lever is pulled in TWICE, you can tell by the rattle sound disappearing and then reappearing )

[ame=http://www.youtube.com/watch?v=SP4uy5OXZjk]YouTube - Karata Open Primary - Big Dog K9[/ame]

 

[dingo]

I am no expert but I believe that may be normal "chatter".....have the same thing for 4 years on my 3" karata.....I understand that the chatter is worse on other brands but do not know from first hand experience....you may want to check the splines on the hub to make sure they are not wearing away ....I had a bad wear problem with mine and had to replace the hub.

 

[nine lives]

What Chris said. My experience with open primary is that clutch plates chatter when clutch is not engaged. You can also check to see that all the bolts are at proper torque.

 

[woodbutcher]

i would say to go straight to the source and give Jim a call and ask him about it.

 

[bruce]

If you look into the hub where the clutch plates are you will find grooves where the metal plate that are in-between the clutch plates have worn away grooves. when your bike is idling the plate are making the noise because of the play. I had the same problem and it took awhile before I found it. I talk to Jim at Karata trying to get help and he told me at first it was something different. he sent me another metal plate so I could put a metal plate in first to move everything out one plate which gave me a tight fix for a little until it worn there also and now the noise is back. I was not to happy with want happened he did offer to give me my money back, because it is happening because of the way it is made and the materials, but I kept it and have just been living with because I do like the open primary and Jim has been helpful about it. He did tell me, he was trying something and may have fix in future but I have not heard anything. By the way mine would also not totally release when I pulled in clutch sometime, which the only fix I found was to put some anti-seize on the inside gear part of the hub where the clutch plates are, which seem to be working ( NOT much just a thin coat). I am sure this is your noise if you have any questions more you can call if you would like 717-382-9983

 

[myanoch]

why does the clutch not looked centered in th movie and also when you put your hads on it the space on th 9'0clock looks tighter than 3'0clock

 

[Staffy]

Many Many thanks for your input and quick responses.

I don't want to get ahead of myself - a little history and to Bruce's/Chris' point (you might be right on the money). I had the same and similar NOISE issue with this bike a year ago. In addition I had "clutch creep" - the grooves where the clutch (friction) plates meet the outer rim of the clutch basket were DEEP so we replaced the OUTER clutch basket sprocket. Both the issues seemed to addressed when we did that - NOISE and CLUTCH CREEP. If I remember correctly at that time Jim felt the grooves were acceptable and part of any normal wear. So now that this has happened again within a year I was wondering if it could be something else causing this or just a repeat. I will speak to Jim tomorrow (Have already sent him an email with this link) and keep you posted. (Looks like I'm going have to replace the clutch hub again).

I am ruling out "normal open primary chatter" - This cause when I initially installed the primary there was NO SUCH noise. This happened a year later, then I replaced the outer clutch sprocket - NO noise. A year later, noise again. In addition I have a Mastiff with a similar 4" Karata open primary - NO such noise.


Thanks again - will let you know once I speak to Jim.

 

[dingo]

If you look into the hub where the clutch plates are you will find grooves where the metal plate that are in-between the clutch plates have worn away grooves. when your bike is idling the plate are making the noise because of the play. I had the same problem and it took awhile before I found it. I talk to Jim at Karata trying to get help and he told me at first it was something different. he sent me another metal plate so I could put a metal plate in first to move everything out one plate which gave me a tight fix for a little until it worn there also and now the noise is back. I was not to happy with want happened he did offer to give me my money back, because it is happening because of the way it is made and the materials, but I kept it and have just been living with because I do like the open primary and Jim has been helpful about it. He did tell me, he was trying something and may have fix in future but I have not heard anything. By the way mine would also not totally release when I pulled in clutch sometime, which the only fix I found was to put some anti-seize on the inside gear part of the hub where the clutch plates are, which seem to be working ( NOT much just a thin coat). I am sure this is your noise if you have any questions more you can call if you would like 717-382-9983

Interesting information that Jim is/was working on a fix and I'm glad tried to help you, Bruce.

I love the open primary but in my case, also about 1 year later, Jim claimed rider abuse which was absolutely unfounded and not the case (see karata-piranha-jr-clutch-basket-worn). Note that I had the same wear as chacha did with his RMD.

 

[Staffy]

why does the clutch not looked centered in th movie and also when you put your hads on it the space on th 9'0clock looks tighter than 3'0clock

Good point - Just the camera angle I assure.:2thumbs:

 

[Staffy]

Interesting information that Jim is/was working on a fix and I'm glad tried to help you, Bruce.

I love the open primary but in my case, also about 1 year later, Jim claimed rider abuse which was absolutely unfounded and not the case (see karata-piranha-jr-clutch-basket-worn). Note that I had the same wear as chacha did with his RMD.

SIMILAR ISSUE and identical symptoms - Not sure if you remember but I did PM you when I was going through this the first time. Thought it was more of an isolated case so didn’t think much of it. This is happening way too quick and too often for me – all within a span of 3K miles. Not jumping to any conclusions, let me speak to Jim tomorrow and take it from there.

 

[RCAdd1ct]

The noise is normal for a primary.

In a wet primary the fluid dampens the noise.

I would not worry about it, but I would pull the belt and look for wear ont he transmission splines if you have to work on the seals.

Go here...

EFM Auto Clutch

Scroll to the bottom and play the top left video. It should sound familiar.

 

[big A]

Absolutely normal. I was wondering the same thing when I bought my scoot. It's the price u pay to look cool. The whine sure does sound good when the clutch is pulled in doesn't it.

 

[Staffy]

Absolutely normal. I was wondering the same thing when I bought my scoot. It's the price u pay to look cool. The whine sure does sound good when the clutch is pulled in doesn't it.

Far from the normal whine...and no i'm not whining..LOL. If you turn up the volume you will hear what I am referring to. Its more like a knocking / rattle.

Cool it is..and performs just as well.

 

[Trainguy]

Staffy,
Following this thread, let us know what Jim has to say?
Trainguy

 

[Staffy]

Spoke to Jim this morning who had already “studied” the video at length. Initial thoughts:

• Yes there is most definitely an unusual rattle and noise. This is not ENTIRELY only partially from the clutch – after much deliberation felt that this could be from the tranny (DOG and Back Lash) which is being AMPLIFIED.
• To this point – I am going to reach out to Baker and see what feedback and comments they might have. (I have also sent a PM to RUBWHORE to check this video out – he has had some great exposure on the tranny during his build)
• If in fact the noise was from the PLATES themselves (which most of us keep pointing out – open primary clatter) the BIG question is why would the noise disappear when the clutch lever is pulled in? When the lever is pulled in the plates have the most room to float around within the clutch basket, noise should continue if not get louder.
• Still working in this – in the interim my theory on this one is, over time grooves have developed on the outer rim of the basket where the plates meet. During idle RPM the plates move around causing the rattle. When the clutch lever is pulled in there is room within the basket to move. Due to the centrifugal force the plates are pushed away from the grooves, causing them to lock in place – hence no noise. (Jim, feels this is very unlikely)
• Have some ideas here (on lines with what Bruce did) and will work on them and keep you posted.

Am planning to visit Jim this Saturday so he can get to see this first hand. Hopefully we would have this fixed before then. As always thanks for your input, comments and feedback.
-Staffy

 

[Moespeeds]

Staffy pull your plates and look at the fins, are they worn or beat up? When an open primary wears a bit it will start to chatter, and when you see the plates it should be obvious where it's coming from. Also look at the inside of the basket for any wear. It's normal and if the clutch is functioning, front and rear nuts are tight, then I wouldn't give it another thought. My Ultima is very noisy as is the Primo on the Bourget I ride.

 

[Moespeeds]

Oh and the noise goes away when the clutch is desengaged because the pack gets tight and chatter "as one" rather than individually. Again, it is a very simple system, so if everything is tight, and there is no unusual wear or debris, and it's functioning properly, don't sweat it.

 

[RubWhore]

I have tried a bunch of different stuff rite down to changing clutch plates and I finally looked at the front nut on the crankshaft mine was loose strangley enough after doing all that the noise went away,Jims good people so he will take care of you but I have a different clutch than most as my bike has the Pirana instead of the Pirana junior but I thought the noise was anoying two... so dont think it was a price to pay to be cool

 

[Staffy]

Update

A quick update and interim fix

Bottom line (and in my opinion and findings - no if’s and or but’s) the very distinct knocking rattle is the result of the grooves caused within the clutch basket. In my case this happens typically within ~1000 miles of running with the open primary (again in my opinion ~1000 miles is premature). See pictures below. (I will post a video in a day or two in which you can clearly hear the difference)

A quick an interim fix to this (thanks to the input from forum members and Jim) is to remove the clutch pack in its entirety, then and insert an ADDITIONAL metal clutch plate followed by the original clutch pack. By doing this you move the entire stack out by a “few” and moves the friction plates a hair away from the grooves – minimizing the noise and eliminating the clutch creep. (Should any of you need an additional metal plate PM me, I have a few lying around)

My findings and conclusions are – the clutch basket grooves will develop eventually with any clutch basket, and depending on the level of wear, so the level of noise. What I would like to see and work on is minimizing the wear on the basket to beyond the ~1000 mile mark. Not sure or certain there is a mechanical/technical impact on running the bike with the worn out basket besides a very frustrating “clutch creep” which will develop once the grooves get to a point as shown in the pictures. Notice the grooves are greater as you get closer to the tranny – you can see that in the travel caused by the plates in the “valley” of the clutch basket grooves they actually meet.

 

[05 old dog]

yea that kind of wear in 1000 miles seems a little premature....i just installed a new 4" karata on my scoot and have no clutch chatter at all...just a loud whine...even at idle.