Clutch Hub Bearings & Upgrade Kits

[ricmoran]

My 39 has a 41 clutch hub, 3 stud type.

Was chatteing quite a bit, lubed it up and it has quieted down but is still making noise due to the bearing wear on the flat metal race of the round old style bearings.

Was looking at a kit that has long pencil type 52 bearings and a retainer that looks like the retainer slides up to the hub similar to the retainer for the cage for the ball roller type and then is held in place with similar or the same springs. The 52 bearing kit has no cage so it looks like these float freely on the hub and the only thing that holds them in place until the outer shell is slide onto the clutch hub is a grease.

I've talked with a few people about the various types of newer set ups to help with the chatter and then shift issues.

For those who have done upgrades with thier older style clutch hubs, what's your opinion on the various upgrades available?

One fellow suggest to go with a belt drive and new hub assembly for ultra quiet application and apparently these fit into the primary cover leaving those who don't know without a clue until the bike is started, no chatter means either new parts or new upgrade.

Thanks for any opinion posted.

Best Regards,

Rich

[vph-d]

You can fit the -58 roller retainer and bearings to your hub. The long rollers bridge the groove worn in the hub by the ball bearings. Clutch chatter is not a normal condition, try substituting a different set of fiber plates to see if the chatter disappears.

There are belt drives available that will fit inside the stock primary covers. Belt drives have their own set of problems, like clutch rattle, belt tension, and alignment problems. On the other hand, belts do away with oiling and adjustment issues of chains.

VPH-D

[ricmoran]

VPH-D, Thanks for your reply.

I think I described the noise wrong as the roller bearing hub makes a unique sound with the bearing assembly when the bike is running. Hard to describe it however. I think the best way to describe the sound is steel bearings rolling around with some movement inside a drum, which of course the inner/outer primary cover picks the nosise up and amplifies it quite a bit.

I was suprised to hear a Ducati make the same sound, it was a 998 with a open primary cover so adjustments are easily made on race days.

New heavy duty Police clutch plates are on the way with new clutch springs and the roller bearing kit. I thought about the belt drive after posting this last night but decided that the installation would take more work than what it would bring for me with this bike.

The oiler for the primary chain is a okay system with this bike for me because I don't want to be making a lot of changes that depart from what stock was. The long roller bearings are an upgrade which I think is a good one that will work with the current set up, plus it saves some money.

Thanks for your reply.

Rich

[MJW]

I think you'll find you only need 51 rollers. Make a note of what the lube is like that comes with the kit as you'll need to re-lube next time you service the hub. try not to over do it or the clutch plates will get contaminated as well. Lots of luck to you...Mike

[ricmoran]

Mike,

Thanks for the advice. With the kit they send a little tube of grease, I am not sure what it is as I have not seen it yet. I've used marine grease for a long time on wheel bearings and chassis bearings but I am not certain how well that will work on the clutch hub.

Rich

[ricmoran]

Update on this.

Installed a BDM belt drive, new Police type heavy duty clutch discs, the pencil type bearings and a Tamer. What a difference it all makes.

Something weird about this bike though, the standard clutch rod from the foot pedal to the clutch release arm is measured at 18.5", the one on the bike is 15.75". The clutch release arm that runs accross the transmission top touches the jockey lid when the clutch is disengaged at full throw with the heel down, which then the heel part of the heel/toe pedal does not travel all the way to the floor board.

I tried the longer clutch rod at 18.5" and there is just too much free length remaining for use of the longer rod to make any sense for use.

I've replaced the chinlee (Tiawain ted) throw out bearing with a good OEM made one to be sure that was not the problem as I understand the repop TO bearing could be a problem too.

I am adivsed that the possibility of the clutch release shaft that runs into the kick cover, this has the 2 finger fork slid onto the shaft that engages the throw out bearing when the heel is down may be a repop and could be manufactured off enough to not give the right set for just enough distance travel of the clutch release arm.

Can anyone advise if this would be the case?

The throw out rod bearing rod that runs to the pressure plate is the correct length, the adjustment screw and end of the rod are all clean and even, which the rod is 13 5/8".

So as far as I can tell, the shaft in the kick cover with that works the fork into the TO bearing could be the last remaining problem that is causing the clutch release arm to strike the jockey lid.

Anyone have any ideas or previous experience with this? Thanks in advance for any light anyone can shed.

Rich Moran
18043

[Robert Luland]

The rod I have in hand is 18.5" or check out Palmers book on page #321. When you say the Jokey top. Do you have a rachet top or single selecter? The peddles not going to the board with a 15" rod. I'm going by memory but isn't that push rod suppose to be 11.3/4 inches? Bob

[ricmoran]

Robert,

Thanks for your reply.

Yes, I read Palmers book about the length and also the clutch throw out bearing rod that runs to the pressure plate measures at 13 5/8" which is also listed in the book as the correct length for this transmission.

Was advised here that maybe to change this out to run with the later round small throw out bearing and clutch rod but i think the smae results would occur and want to keep things as 30 - 40'ish as possible.

The lid/transmission top on the transmisson is a single selector and not a ratchet top and is connected to and used with a shift gate on the gas tank, so I suppose use of the word "jockey shift" is not correct for the transmission top.

The linkage system is all stock, OEM spec (not certain of the clutch release lever shaft part # 4 in the service manual big twin 40 - 47 hence the one of the questions of the thread) with exception the clutch rod that connects to the heel/toe foot control is short by more than 2".

Also, I am not certain if the clutch release finger is worn or could wear that far to the point that there would be that much wear to have to mickey mouse the foot pedal rod that runs to the clutch lever would require that much stock removal to get the system to operate as it should.

In the end I am wondering if this anomoly is found with other MC's when so many original parts are mixed with reproduction parts. The bike has the correct engine for 39, transmisson case and top is 39 but rebuilt with 40 and later shift 1 -N- 2- 3-4 so when one sits and reviews the Heinz 57 mix of parts, does one say "this is the best I have to work with or am I missing something here?"

Best Regards,

Rich Moran

#18043