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beemergirl
03-09-2009, 11:26 PM
I just picked up a used '09 RT :brad and I read through a lot of old posts on wet vs dry clutches. I've been riding wet clutched bikes for a few years.

Practically speaking, do you need to treat the dry clutch differently when riding as opposed to a wet clutch. I understand the dry clutch gets hot in traffic....but is there something you're supposed to do to prevent that?

Motorwerk
03-10-2009, 12:09 AM
Congrats on the new bike! You're going to enjoy it!

A dry-clutch is less forgiving in regards to slipping and wear. Also, because it's not bathed in oil it can feel a bit rough compared to a wet-clutch. You may notice an odor similar to brakes being agressively applied if it's been in the friction zone longer than desired.

For longevity you'll want to be expediant with changing gears, only to keep it in of the friction zone for as short a time as possible, especially starting from a stop. Early on, if you have not already experienced this, the engine may stall if not given enough RPM's when starting out. As the engine wears it will gain power at lower RPM's and this is no longer an issue. Generally, just try get started as quickly as possible while using as low an RPM without stalling. With practice you can usually get the clutch fully engaged within a single tire rotation.

A dry clutch can have a very long life if treated appropriately.

Good luck with the new ride! :dance

PGlaves
03-10-2009, 01:00 AM
If you go to 15 or 20 rallies a year and always enter the field events then wear on the dry clutch will be significant. Probably wear it out in 50,000 miles. If you normally commute and/or tour expect 100,000 to 200,000.

They do not like to be slipped - and can get hot when you do it. So use it like the dry clutch in your car and expect long life and good service.

peterb
03-10-2009, 03:30 AM
I would never argue with Paul G [I'm afraid of his wife! <g>] but, I believe you will have good life from your clutch if you remember to put the bike in neutral as you roll to a stop. It is easier to put in neutral while still moving than it is to try to find neutral while stopped - which of course is heating up the clutch.

I can't be doing much wrong as I have never replaced a clutch in any vehicle, 2 or 4 wheels in my 50+ yrs of driving/riding.:dance

Its pretty intersting to see bikes stopped at lights and the rider is holding in the clutch, gunning the engine, letting the clutch out a bit, then gunning some more. That will surely get you the smells, the heat, the worn clutch quickly.

Have good and safe rides.:brad

beemergirl
03-10-2009, 03:41 AM
Thanks for the replies. In MSF class they tell you to stay in first at stop lights....so that you can prevent getting rear ended. So I've always been one to hold the clutch in and stay in first while everyone else is handsfree. Guess it's time to join them and be handsfree.

Of course when I drive a manual transmission, I'm the one sitting there gunning the engine waiting for the light to turn too.....I guess I have some habits to unlearn.

So far I'm just trying to feel comfy on this huge thing. Only stalled once today. Trying to figure out what all the things on the computer are and I'm going to have to reset the clock as we silly Americans have to change the time twice a year.

PGlaves
03-10-2009, 03:54 AM
If properly adjusted - and if pulled all the way in - the dry clutch will be fully released and not get hot or wear at those stop lights. BUT - as long as it is pulled in there will be pressure on the throwout bearing which will then encounter accelerated wear.

I understand the MSF position about being poised to accelerate to escape a rear-ender. It has merit. At the risk to the long run health of the throwout bearing. For very short stops I keep the clutch in. At long red lights at traffic signals I feel fairly safe going into neutral as soon as one or two cars have stopped behind me.

I am paranoid however in those construction zones where a person with a hand held stop sign has me at a dead stop, exposed to the rear, in a 55 or 60 or 65 mph speed zone. Once a semi has stopped behind me I'm less paranoid. Or 5 or 6 cars.

F1Turbo
03-10-2009, 04:28 PM
I'll always err on the side of safety versus possible earlier wear and maintenance, especially as drivers seem to grow less attentive (cell phones, texting, dvd watching...) every week.

Polarbear
03-11-2009, 03:53 AM
Watching mirrors as you stop and use neutral often, when stopped are both good advice, imo...I use neutral most always, BUT never take my eye off whats approaching my six, either:). I can find first gear, very "rapidly" if needed and if you're watching, you'll know when! CHP(Ca.M/C Cops) are getting, I think an avg. 60000 on clutches(avg.) and they are HARD use RT Bikes...This is what I heard at a BMW shop, servicing CHP RT's...They are known for rapid accel starts as they chase down speeders. A few other clutch TIPS, I find useful:). Once under way, very "little" clutch lever is needed to shift gears and you'll find the "sweet spot" for shifting with practice. Less lever travel, equals less wear....Higher gears, 4th to 5th shifting is soooooo very easy without a clutch AT ALL:). The ratio is so close in these gears, that a shift without the clutch is elementary. Roll the throttle off and shift up. I do not downshift mine this way, as I find it a different proceedure entirely and not as smooth for me. I think you'll find many road racer types use much less clutch and mostly none! :thumb :usa Randy

blongb
03-12-2009, 02:08 AM
So why doesn't our R1200RTs have a wet clutch? Other than it probably is more expensive (like I didn't pay enough for it), why in the world didn't they put a wet one in? :dunno Seems like the wet clutch is the perfect arrangement for a "made to be abused" motorcycle.

darrylri
03-12-2009, 02:33 AM
A wet clutch means having the transmission share oil with the engine. This means that the oil and especially the additives package that gives it multi weight viscosity, get chewed up by the gears. It also limits to a certain extent which oils you can use so that the clutch works properly. The byproducts of combustion which form an acidic brew will then be circulating in your transmission as well as in your engine, and the clutch wear ends up circulating in both your transmission and your engine.

But mostly, it's because of tradition. The boxers have always had a dry clutch, from 1923 to now, and it, along with the boxer configuration and the shaft drive, form a signature for this line of BMW motorcycles.

There's nothing really wrong with a dry clutch, you just have to treat it a bit differently. I've never, in over half a milliion miles on primarily 5 bikes, even gotten half way through a clutch. They are rugged and long lived, but at the expense of a somewhat more abrupt engagement. This hasn't kept Ducati and Moto Guzzi from using it, either.

blongb
03-12-2009, 03:53 AM
Excellent reply, thanks much!!! I support tradition!!!:thumb

Regards,
Bill

2008 R1200RT Sand Beige
2006 Kawasaki Z750S Black
1985 Mooney 201

ragtoplvr
03-12-2009, 04:02 AM
It actually would be possible, to seal the area of the clutch, use a wet clutch starter, and have a single or multidisk wet clutch. Of course we would have lots of threads about leaks. It would weigh more, and we would have to put up with more best brand and viscosity of oil threads.

I think I am preferring dry.

Also remember, a wet clutch is not indestructible.

An alternate transmission arrangement, where the current compensator shaft extends to the end of the transmission, and a wet clutch located there, could be changed without dropping the trans, but it would be longer and weigh more.

One of the reasons we love our beemers is the light weight for the size. Given the engine arrangement the dry clutch is simple and light, but a PIA to change.

If only BMW would extend the spline thru the friction disk, and machine the housings correctly (German machinists used to be famous) it would be quite suitable.

Rod

blongb
03-12-2009, 05:22 AM
Doesn't the multi-disk feature of the wet clutch make it much much more reliable?

darrylri
03-12-2009, 12:29 PM
Doesn't the multi-disk feature of the wet clutch make it much much more reliable?

That's not clear to me. Each of the friction disks and the pressure disks represents a potential failure point. What a wet clutch does is fit into a smaller diameter area, because the friction material is stacked up rather than being spread out over a larger single disk, as our BMW boxer clutches are.

You do get a softer engagement because, as you release the clutch, you can control it as each individual disk becomes locked to its pressure plate. In a dry clutch, you only get the space as the single clutch plate becomes locked to the pressure plate for feel.

In the late 1920s and early 1930s, BMW did try to add more feel to their clutch operation by including two dry clutch plates with a separating pressure plate between them. When I get my R12 on the road, which has this arrangement, I'll let you know how well it works. :)

osbornk
03-12-2009, 12:45 PM
The difference between a dry clutch and a wet chutch is simple (for the mechanically inclined) if you compare it to a car. A dry clutch is just like the clutch you find in a standard transmission car. A wet clutch is just like a clutches you will find in an automatic transmission (multiplate with friction plates sandwiched between each clutch plate).

You treat a dry clutch on a motorcycle exactly like you treat the clutch on a standard transmission car.

FredRydr
03-12-2009, 01:05 PM
In the late 1920s and early 1930s, BMW did try to add more feel to their clutch operation by including two dry clutch plates with a separating pressure plate between them. When I get my R12 on the road, which has this arrangement, I'll let you know how well it works. :)
I take it you've done some interesting customizing. Are you going to write an article? Did you make the parts, or adapt them from another vehicle?

Fred

darrylri
03-12-2009, 02:12 PM
I take it you've done some interesting customizing. Are you going to write an article? Did you make the parts, or adapt them from another vehicle?

Fred

Not customizing at all, just putting it back to stock. The R12/R17, the preceding R11/R16 and some late R52/R57/R62/R63 models all had two clutch plates and a separating pressure ring all sandwiched inside the flywheel. Parts, while not cheap, are available. If you look carefully at this photo, you can just see the two individual plates' splined teeth:

http://darryl.crafty-fox.com/mcpics/2008/R12/P3055202_crop.jpg

texanrt
03-12-2009, 02:29 PM
Here's a page with some exploded views of various clutches. http://www.dansmc.com/clutchexploded.htm

The clutch on my HD sits on the transmission's input shaft tied to the engine by way of the primary chain. It's lubricated independent from the engine, so clutch oil isn't affected by combustion as far as I know. The problem with this configuration is that it's big, bulky, and heavy -- but that's part of being a Harley.

It took me some practice to get acclimated to the dry BMW clutch -- I stalled it a few times until I got used to how quickly it engages compared to the HD. I smelled that dry plate smell a couple times, but as Paul mentioned, the more miles I've got, the freer the engine revs and there's ample power to motor away from a stop even two-up.

PGlaves
03-12-2009, 04:53 PM
I've owned lots of cars in the past 50 years. Most of them "stick shifts" with a manual transmission and a dry clutch. To my knowledge I've never seen a car with a multi-plate wet clutch. So since BMW uses this system on some of their motorcycles - the ones with longitudinal crankshafts and drive shafts for which they make sense - that is somehow inferior to the Asians???

There is virtually no downside to a dry clutch in typical motorcycle commuting or touring. Slipping it for lots of very slow speed maneuvers during field events or law enforcement operations is of course the exception.

Motorradfahrer
03-12-2009, 05:44 PM
Lousy clutcher?..wanna long life clutch that lasts the life of the bike...No smell...No overheating...can clutch the be-Jesus out of it....? Get a $$$$$ Ceraminc clutch disc plate. Clutch won't wear out but pressure plate might.

http://www.toursforafrica.co.za/old/accessories/General%20Access/A-Ceramic%20Clutch%20Plate.htm

:dance :usa :german

ANDYVH
03-12-2009, 06:25 PM
I agree with most of the posts above, especially with Paul Glaves. I'm also an MSF instructor and have used my 94 RS for ERC classes with no detriment to the dry clutch. I too, hold the clutch in, and stay in gear, at a stop until I know fairly certain that nothing is happening behind that may need me to take off quickly.

I keep my clutch adjusted exactly to spec (I feel it does make a big difference), and check it a few times during my typical 10,000 mile riding season. I also make sure my clutch splines are clean and lubed with the tacky grease recommended by BMW. My RS has 140,000 miles on it, now on the 2nd clutch assembly, that I installed myself. It has great light feel to it with good lever travel. I replaced the original clutch cable at 115,000 not because I had to, I just did it to avoid a potential roadside issue.

I don't quite agree that a wet multi-plate clutch would be more reliable. A wet clutch requires a lot more friction surface to transmit the engine power, so you have multiple friction plates. But a wet clutch, again because of the multiple plates does tend to have easier/better feel and takeup, and a wider friction zone than a single plate dry clutch. Learn to make quick efficient shifts (each shift should take no more total time than a finger snap). And once the bike is moving, you really only need maybe 1/3 of the clutch lever travel to make an up or down shift. Preload the shift lever to take up the slack in the shifter, in prep for the shifts. In fact, less clutch lever travel is better than squeezing the lever to the grip every time.

bikerfish1100
03-12-2009, 07:06 PM
I would never argue with Paul G [I'm afraid of his wife! <g>] but, I believe you will have good life from your clutch if you remember to put the bike in neutral as you roll to a stop. It is easier to put in neutral while still moving than it is to try to find neutral while stopped - which of course is heating up the clutch.

that statement makes no sense whatsoever. Heat/wear to the clutch discs occur when there is slippage between the pressure plate and the clutch plate, and that does not happen at a stop- unless you intentionally "play" with the clutch.

I can't be doing much wrong as I have never replaced a clutch in any vehicle, 2 or 4 wheels in my 50+ yrs of driving/riding.:dance

Its pretty intersting to see bikes stopped at lights and the rider is holding in the clutch, gunning the engine, letting the clutch out a bit, then gunning some more. That will surely get you the smells, the heat, the worn clutch quickly.

again, if the clutch is fully disengaged, it matters not at all what the engine is doing- as the two systems (engine & trans) are fully isolated from one another. Gunning the engine does nothing to the clutch- the "letting clutch out a bit" and rolling back and forth does wear the clutch, but it's likely minimal, unless it's going on with lots of engine revving at the very same time

Have good and safe rides.:brad

i wasn't going to comment, but i hate to see a noob get misinformed.

clutch wear happens when you ride the bike in the friction zone, period. dry clutch bikes are much less tolerant of living in the FZ than are oil immersed clutches.

as PG stated, there will be some slight wear to the throw-out bearing by leaving the bike in gear/clutch disengaged at a stop... but the wear is relatively insignificant.

continue doing as you were taught in the BRC- it's the safest advice.

the biggest advantage of a multi-plate wet clutch are two-fold. 1) more tolerant of slippage/FZ use. 2) relatively easy/cheap to replace, as the clutch pack is usually situated on the side or above of the transmission, rather than sitting in-line between the engine and trans as our dry clutches are.

beemergirl
03-12-2009, 08:03 PM
Thanks everyone, I'm still listening.
In the few days I've had the bike I've become very conscious of the time I spend in the friction zone. Since of conscious of it, I can start working on lessening the time spent there.

Nancy

Penforhire
03-13-2009, 12:40 AM
Some riders seem to need more time in the friction zone than others, especially starting from a stop. In that regard wet clutches are so much more forgiving. I am more conscious of getting quick engagement with my dry clutches.

I don't see a major drawback to wet clutches so I'd prefer one on my RT. Shared oil hasn't seemed to harm the many Japanese wet-clutch bikes I've had over the years. Of course, those were water-cooled so perhaps the oil allowance is different. OTOH, I do hear tales of individuals frying their dry clutches prematurely.

I haven't changed a throw-out bearing on a Hexhead. Is it significantly harder or more expensive than Airhead's multi-bearing disk? Otherwise I'd say let 'er fry because that part is cheap and easy to replace.

darrylri
03-13-2009, 05:14 AM
I've owned lots of cars in the past 50 years. Most of them "stick shifts" with a manual transmission and a dry clutch. To my knowledge I've never seen a car with a multi-plate wet clutch.

My 1971 (?) Honda 600 car had a multiplate wet clutch. (That would be the really little bitty one, smaller than the original Civics.) It had "4 on the dash", as there was no room to put the stick on the floor.

joelaw
03-13-2009, 07:25 AM
[QUOTE=PGlaves;433683]I've owned lots of cars in the past 50 years.* Most of them "stick shifts" with a manual transmission and a dry clutch.* To my knowledge I've never seen a car with a multi-plate wet clutch.* QUOTE]

There may have been others, but I know that 1941 and 1947 Hudson automobiles had wet clutches.

As has been note in other posts, HD uses wet clutches and porbably have for ever. On the HD the clutch shares oil with the primary chain drive, not the transmission or the engine.

In the nearly 30 years of riding BMWs and a little over 500K miles, I have had really good service from the dry clutches on these motorcycles. I have '91 K100LT with 104K miles and as part of some extensive preventative maintenance, I had the clutch replaced, it was worn but still had many thousands of miles of live remaining.

As several other repliers note, I too never put the transmission in neutral at red lights. The key, as has been pointed out by others, is to keep the clutch adjusted properly and get the clutch fully engaged a quickly as possible when getting underway.

osbornk
03-13-2009, 11:25 AM
My 1971 (?) Honda 600 car had a multiplate wet clutch. (That would be the really little bitty one, smaller than the original Civics.) It had "4 on the dash", as there was no room to put the stick on the floor.

The the little bitty car had a motorcycle engine in it.

Paul_F
03-13-2009, 11:58 AM
After having read all of these posts, I have obviously been putting too much strain on my clutch when practising slow speed U turns, with the throttle steady and the clutch regulating speed. Am I correct in assuming slow U turns with a beemer should be done with more trail braking to regulate speed rather than using the clutch?

darrylri
03-13-2009, 01:32 PM
The the little bitty car had a motorcycle engine in it.

Yes, that's right, it had a 600cc water cooled twin and a wet clutch, all sharing the same oil with the transmission. It had a lot of motorcycle tech in it, and was surprisingly full featured, too. For example, it had a 3 range, fully variable speed setting for the windshield wipers. Heck, even BMW's Z3 didn't have that.

Mine was crushed by a speeding Chevy Nova that ran a red light and T-boned me as I was completing a left turn. Sounds like a motorcycle accident! The driver just didn't see me (or the other two lanes of traffic that were already stopped for the light).

Motorwerk
03-13-2009, 04:53 PM
Am I correct in assuming slow U turns with a beemer should be done with more trail braking to regulate speed rather than using the clutch?

That's correct, it's more of an on/off accelerator than clutch-slipping exercise. A bit more difficult but quite managable.

In regards to pre-loading the shifter; while that was almost mandatory for a smooth shift in pre-Heaxhead transmissions it's not so necessary now but still helps a bit. The trannys are vastly improved. All the gyrations of managing the 1100 compared to the 1200 are a thing of the past.

Nancy, don't worry too much about it you will get better with practice. Just know not to linger in the friction zone. On occasion you will know you've been there too long and why and sometimes you may not have a choice.

Tom K.
03-13-2009, 04:55 PM
Thanks for the replies. In MSF class they tell you to stay in first at stop lights....so that you can prevent getting rear ended. So I've always been one to hold the clutch in and stay in first while everyone else is handsfree. Guess it's time to join them and be handsfree.

Of course when I drive a manual transmission, I'm the one sitting there gunning the engine waiting for the light to turn too.....I guess I have some habits to unlearn.

So far I'm just trying to feel comfy on this huge thing. Only stalled once today. Trying to figure out what all the things on the computer are and I'm going to have to reset the clock as we silly Americans have to change the time twice a year.

My technique (in cage or on bike) at lights is to try to see when the cross traffic light turns yellow, at which point I shift from neutral into first.

I'd also mention that the RT has a very high 1st gear (about 53 mph @ redline), so co-ordinating throttle & clutch for a smooth start may require some practice.

Re changing clocks, for the first time, I managed to set the time in my car without resetting the trip odometer!

Enjoy your RT!
Tom

mikeb921
03-14-2009, 10:36 AM
Interesting thread. I'm surprised no one has mentioned the hydraulic aspect of our new hexhead clutches. I, for one, have grown acustomed to the feel and "take up" of the new system for normal starts but I can't seem to get a good feel for quick launches. I like the idea of it being hydraulic (been working for decades in autos) but I think BMW needs to continue experimenting with the size of the master cylinder and or the slave cylinder until they can get it to engage more like a cable operated set up. As far as wet versus dry, I can't imaging a "Boxer" with anything but dry. It's been working well for them for a very long time.

MB

mpmarty
10-25-2010, 08:02 PM
Regarding the high first gear and dry clutch I find myself slipping the back tire instead of the clutch:dance

ragtoplvr
10-25-2010, 09:13 PM
Some other comments.

on a 1150, the Bosch 4417 4 electrode plug gives better low RPM (like at idle) then the OE or the autolight.

I set my idle a bit more than recommended at about 1200 to 1250 RPM, particularly in the winter. I can easily although slowly pull away and never touch the throttle, or pull away a bit faster and never slip the clutch above 1000 RPM, I can not do this on my bike using any other plug.

I have smelled the clutch before, particularly in a panic situation, stopped at the light and notice a HUGE ford truck grill gaining rapidly with MY name on it. But slipping at 6 or 7K rpm in a case like that is not only allowed, it is preferred, if I had stalled it I would not be typing this. BTW that truck continued right thru the intersection without hitting anything as I struggled to not drop mine on the shoulder after getting out of the way! Adrenalin is wonderful, and one leg was really sore from over straining the next few days.... Watch your 6 folks. One car actually circled around to make sure I was OK as I paced off the adrenalin in a parking lot.

Rod

Polarbear
10-25-2010, 10:24 PM
Nothing is as important than your 6, when stopped or coming to a stop. I still always use neutral at most stop lights and never take my eye off my 6 as i'm doing so. Clutch use? Well, all must decide for themselves, but I can garantee my foot hits the footpedal and shifter at the same time, when pulling out. Its a bone chilling excercise to hear tires screeeching from behind as you sit at an intersection:(... Its good advice to always have an "out", when you do need it, so break all the rules to save your life when this occurs. Any rider, riding long will have this happen someday! Clutch in or out, just know how to find first and move quickly. For us neutral guys/gals, its a one movement excercise. Clutch, foot, throttle all come together in one motion in a split second. Thats how I see it and do it, Randy:usa

mpmarty
10-26-2010, 12:20 AM
There has been a whole bunch of construction work on the road from my home into the nearest town. Frequent flaggers stopping traffic. When I arrive at the tail of the line I pull over onto the right shoulder where possible and move up along side of the last vehicle. I still watch my mirrors. I got rear ended at a stop light in Florida in '85 on my Yamaha Virago 920 and got blown into the middle of the intersection. Fortunately I didn't end up getting hit by crossing traffic. 4X4 Pickup "didn't see me". Not something I ever want to repeat.

169993
10-26-2010, 01:04 AM
I normally do not read this forum, as I do not own a Hexhead not do I know anyone who does. That said, I do know a little about clutches.

As far as Harleys having a wet clutch, the older ones do not. I can't speak on Evo engined bikes, but I know a lot about Harleys from 1982 and earlier.... Although they do have a multi plate clutch running in a primary case with a lubed (either oil drip or oil bath) multi row primary chain, the clutch itself is dry. What I mean by this is the clutch is not bathed in oil nor does it need to be to work properly. In fact, if enough oil gets on the plates it will lead to slipping. I have replaced the primary chain with a belt drive on many of these bikes and no modifications whatever are needed to the clutch. On the earlier tin primary bikes, one simply turns off the chain oiler. On the later alumimum primary HD's one runs without any oil in the case.

This same analogy is also applicable to earlier pre-unit construction Brit bikes. They are multi plate clutches and will operate quite happily dry. The main reason for multi plate clutches is to furnish an adequate surface area without having a large diameter clutch.

HD's also have a pressure plate with three studs holding it on. Thes studs are asymetrically spaced to give the pressure plate an inherent wobble. This greatly aids in a gradual engagement of the clutch rather than the sudden grab already spoken of here.

As far as the longevity of a dry clutch, think of a semi truck...They all (assuming a manual trans) have a large dry clutch and last for hundreds of thousands of miles trouble free.

marchyman
10-26-2010, 01:42 AM
As far as the longevity of a dry clutch, think of a semi truck...They all (assuming a manual trans) have a large dry clutch and last for hundreds of thousands of miles trouble free.

And are only used for starting and stopping.

PGlaves
10-26-2010, 03:29 AM
I have been pondering which is the least desirable: a wet dry clutch or a dry wet clutch. I haven't decided but tend to think the latter might be worse, but I'm not sure.

mpmarty
10-26-2010, 03:39 AM
Worse! particularly in the old Hudson cars. their friction material was cork. No wonder they kept the clutch filled with oil.

bikerfish1100
10-26-2010, 04:05 AM
my thinking was based on the fact that i can't really think of a wet clutch bike that does not share its oil supply with the engine/trans-so if the clutch is dry, it means the engine is too. bad, and expensive, business, that.

Polarbear
10-26-2010, 09:44 PM
Both are rides that rarely use clutches! The rigs are a startoff and stop clutch routine, rarely touching the clutch pedal otherwise and most all my biker racing pals have said they rarely shift with a clutch either. The hardest folks I know on BMW clutches are the CA.CHP, professional riders on RTs. These guys like really fast takeoffs from shoulders, chasing speeders and take most of their clutches out at 60000m., according to a local BMW Dealer that does the work. Wet or dry, I cannot remember ever changing one on most my bikes, with one exception. I have a R100/7 with 370000m and its on a second clutch:), so long ago I forgot when I did it. Randy:usa

mpmarty
10-26-2010, 09:54 PM
Yeah But.... Many years ago on vacation as I was nearing St.George Utah my clutch started letting the engine get away in top gear on hard pulls. I limped into town and found a dealer that was open. I was at that time riding a Suzuki 1150 as I recall. The shop manager informed me it would be three days before they could do a clutch job as they were stacked up with work and the clutch would take between four and six hours to do. I asked if the parts were available and they were in stock. I informed the shop I would perform my own clutch replacement in their parking lot using tools I had with me. The shop foreman laughed at me and told me I'd be at it all night. I told him I'd be done in less than an hour or I'd buy him dinner. Gathered parts and took bike onto dirt parking lot. Placed our plastic rain gear on the ground as a "pad" and laid the bike on its left side. Pulled cover and replaced clutch plates and put it back together. Total time 45 minutes and I was careful. It took more time to clean and check the gasket surfaces than to exchange the clutch plates and steels. Springs were fine. Shop guy bought us both dinner that evening.:thumb I hate to even think of trying that on my RT.

ragtoplvr
10-26-2010, 10:03 PM
I have been pondering which is the least desirable: a wet dry clutch or a dry wet clutch. I haven't decided but tend to think the latter might be worse, but I'm not sure.

The Harley guys like the big wide dangerous open primary belt kits. Now I know of a rat Harley type that just took off the primary cover. left the chain, put in a roller tensioner made from a combine part? and ran it that way. It smoked a bit a first, then got a bit grabby, and then was fine. I thought he was a idiot, BUT hey, his ride. Of course, 1000 miles in a year as it wobbled from bar to bar is not a good test. He would squirt some oil on the chain and throwout bearing once and a while. I saw it running down the road the other day still open primary. So I think a wet dry clutch is worse.

Rod

tinytrains
10-27-2010, 12:30 AM
My 1971 (?) Honda 600 car had a multiplate wet clutch. (That would be the really little bitty one, smaller than the original Civics.) It had "4 on the dash", as there was no room to put the stick on the floor.

Actually, the 600's had a single plate dry clutch, with a primary chain to the input shaft. At least every one I ever saw, and I saw a bunch back then. A 35 HP car, woo hoo! Today, my 160 HP Mazda 3 gets better fuel mileage than my 600 ever did.

The only cars I can think of with multi-plate clutches are Formula one cars, but they seem to be dry. http://http://www.youtube.com/watch?v=89kE6mcF2JM

As for holding the clutch at a stop, like most, I hold it in first gear until there is a good sized line of cars stopped behind me, or no one in sight.

Scott

bikerfish1100
10-27-2010, 12:51 AM
The Harley guys like the big wide dangerous open primary belt kits. Now I know of a rat Harley type that just took off the primary cover. left the chain, put in a roller tensioner made from a combine part? and ran it that way. It smoked a bit a first, then got a bit grabby, and then was fine. I thought he was a idiot, BUT hey, his ride. Of course, 1000 miles in a year as it wobbled from bar to bar is not a good test. He would squirt some oil on the chain and throwout bearing once and a while. I saw it running down the road the other day still open primary. So I think a wet dry clutch is worse.

Rod

rod- i'm missing your point here. H-Ds run a (mostly) dry clutch (minus whatever minimal splatter tehy could pick up from the primary chain lubrication process), and opening the primary changes nothing in that equation. what did i miss?

ragtoplvr
10-28-2010, 02:54 PM
It is a wet clutch, just splash lubed..lots of splash. Wet clutch is not normally immersed in oil. There would be too much drag. This is also true on automatic transmissions. Some bikes even have jets to squirt more oil on the clutch.

At work I have a test bike for testing starters, with window in the primary. Even at cranking speed there is a LOT of oil moving around. You should see it running. At rest part of the plates are immersed. At high RPM basically the entire housing is filled with a thick oil mist.

Rod

bikerfish1100
10-29-2010, 12:15 AM
It is a wet clutch, just splash lubed..lots of splash. Wet clutch is not normally immersed in oil. There would be too much drag. This is also true on automatic transmissions. Some bikes even have jets to squirt more oil on the clutch.

At work I have a test bike for testing starters, with window in the primary. Even at cranking speed there is a LOT of oil moving around. You should see it running. At rest part of the plates are immersed. At high RPM basically the entire housing is filled with a thick oil mist.

Rod

gotcha. thanx.

169993
10-29-2010, 01:37 AM
Sorry Rod...'Fraid I'm gonna have to disagree with you...HD's do not run a wet clutch...The differenct between Japanese and Harleys is....Hondas, etc use a serrated clutch basket that runs in a common oil bath with the rest of the eng/ trans/primary gears...This allows for a total soaking in oil..HD's use a solid walled clutch basket that permits virtually none of the primary chain oil to get into the clutch itself. This is for the big twins...The older Sportsters did use a wet clutch, which combined with the 50W HD oil guaranteed the rider had no clutch at all with a cold engine. If the big twin clutch got oil soaked it would slip badly.

gsrider05
10-29-2010, 12:38 PM
I have a Harley Ultra Classic and the clutch is definitely soaked in oil. Have you ever added oil to the primary of a Harley? You have to soak the plates in oil when you install the clutch too. This oil is separate from the other two oils on the bike also.

169993
10-29-2010, 02:58 PM
Perhaps I should have clarafied my latest post...In my earlier post on this subject I said I know nothing about Evo engined era HD's...My statements are in reference to non Evo engines, commonly known as shovelheads and earlier bikes...I will still say they run a dry clutch due to their construction.

ragtoplvr
10-29-2010, 03:19 PM
I do not ride Harley's BUT I do get involved in them a bit from time to time.

The only times I have taken a Harley clutch apart the plates were wet with oil, the few times do NOT make me a expert. At rest the oil level overlaps the disks, so they do get some oil. Maybe they are a new class, Damp Clutch. Now on to the real question, what is the best oil for a damp clutch:whistle

Rod

PS I think when any of them fail they are a Damn Clutch though.

bikerfish1100
10-29-2010, 10:54 PM
I do not ride Harley's BUT I do get involved in them a bit from time to time.

The only times I have taken a Harley clutch apart the plates were wet with oil, the few times do NOT make me a expert. At rest the oil level overlaps the disks, so they do get some oil. Maybe they are a new class, Damp Clutch. Now on to the real question, what is the best oil for a damp clutch:whistle

Rod

PS I think when any of them fail they are a Damn Clutch though.

at rest a Harley clutch pack should be dry. As in close to totally. The only oil it is exposed to is that from the primary chain oiler, which feeds off the motor oil line at a t-fitting (at least, that wa how it used to be). Very little oil should be collecting in the primary case; tablespoons worth of. If significantly wet, i'm suspecting a blown trans output shaft seal, of a blown left side motor seal.

oh yeah, same caveat as copandengr, i'm old school H-D too.

ragtoplvr
10-30-2010, 12:32 AM
I have zero experience on older Harley Davidsons. The later ones hold about a quart of 20W 50 in the primary, complete with drain plug, fill port and chain tension shoe adjustment port. Your early ones in fact do appear to be dry, but the later ones are wet.

Rod