clutches and coils

discussions specific to the 907IE
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93IE
Posts: 110
Joined: Sat Apr 04, 2009 9:21 pm
model: 907 I.E.
year: 1993
Location: Georgetown, Texas

clutches and coils

Post by 93IE »

My clutch on the 907 is getting a little louder these days. i read up on Barnet kevlar clutches. Anyone tried them? and should I also replace the clutch basket.

Still trying to determine if I need 3 or 4 ohm coils for my 907. I was going to purchase Dynas Any help is appreciated
Preston
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blazing928
Posts: 222
Joined: Tue Sep 15, 2009 4:08 am
model: 907 I.E.
year: 1991
Location: Melbourne Vic, Australia

Re: clutches and coils

Post by blazing928 »

Barnett seems to be the main choice for replacement. Price varies a lot on ebay.
I think the plates the friction surface is attached to is alloy , so a small weight saving.

The desmo times book says the basket is ok as long as its not notched by the clutch plates wearing into the sides. Thats the chatter noise.

I have replaced my basket with the MPL Tuning along with a MPL slipper clutch. All up its a lot lighter, supossedly will let the motor spin quicker, whatever!

Haven't riddden it more than 500m as I am doing other stuff [!!!], however in that short distance its very apparent that the slipper has changed the bike a lot, no where as much jerk when you lift off, also the bike is quieter on the over run as the bake wheel is not engine braking like a truck.
Big loss of Ducati character maybe, but i wanted the safety on downchanging, also prevents over reving. Clutch wear is greater as in traffic the plates get a lot more use.

As I have limited experience I am sure others will post
Nigel

91 907IE - full restoration
91 907IE Red, Wilbers, Staintune Conti, Corbin,
MPL Slipper,Ceramic exhaust

Lambretta LI150 S3
87 928S4

http://www.paolopirozzi.com/it/ - around the world on a Multistrada

907, its not a bike , its a cult
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du907
Posts: 346
Joined: Fri Jul 08, 2005 12:00 am
model: 907 I.E.
year: 1992
Location: Winston-Salem, N.C. USA

Re: clutches and coils

Post by du907 »

Clutches: Ducati replacement is not that much more than the Barnett. Remember the factory clutch basket is steel. The factory plates are steel. They do make alumin. drive plates (the ones with the tabs and the friction material). However, if you mix the alumin. with the steel basket, the alumin. tabs will wear down much faster than the factory steel ones. There are several aftermarket manuf. that make alumin. clutch baskets. It makes sense, use steel with steel and alumin. with alumin. I have had both and I have gone back to the factory clutch because it lasts longer. Also, the original paso basket is slightly different than the part no. replacement that is basically the same as the 900ss, 916, etc. The bottom is slightly flat whereas the newer replacement is rounder. So the plate staking is slightly different with the new basket.
du907
Mc tool
paso grand pooh-bah
Posts: 1974
Joined: Wed Dec 05, 2007 12:35 am
model: 906 Paso
year: 1990
Location: Riverton New Zealand

Re: clutches and coils

Post by Mc tool »

93IE wrote:My clutch on the 907 is getting a little louder these days. Preston
Oh so its all quite normal then 8) . There is a mod that can be done quite sucsessfully to shut the rattle up , using nothing more than an old clutch plate . I did it on my SS as it was really bad but never bothered with it on the paso as was quiet . possibly the difference between an alloy flywheel and a steel one... dunno
I wish I was young again............Id be heaps smarter than last time
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jpitz31
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model: 750 Sport
year: 1990
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Re: clutches and coils

Post by jpitz31 »

Quite normal as the clutch starts to wear. From time to time remove the clutch cover and blow out the area with compressed air to remove the dirt and clutch plate dust.

Dry clutch noise is all part of the experience of riding a Ducati :mrgreen:

Cheers

Joe
1990 Ducati 750 Sport (mine)
2007 Piaggio BV 500 (mine - daily driver)
2008 Piaggio MP3 500 (wife's)

My Ducati Blog site
http://projectducati.blogspot.com/

Stupidity is not a crime, your are free to go ;-)
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Fraser
Posts: 334
Joined: Tue Jan 17, 2006 12:00 am
model: 750 Paso
year: 1986
Location: Lower Hutt, New Zealand

Re: clutches and coils

Post by Fraser »

Joe,

Clutch rattle is such a feature of Ducati that you need to share it. Hence the after-market clutch covers with all the cut-outs, holes, penetrations etc.
Let everyone hear it and share.

Fraser.
750 Paso
1980 Moto Morini 500 Sport
Mc tool
paso grand pooh-bah
Posts: 1974
Joined: Wed Dec 05, 2007 12:35 am
model: 906 Paso
year: 1990
Location: Riverton New Zealand

Re: clutches and coils

Post by Mc tool »

The mod I speak of stops the rattle but ( by virtue of the fact that the rattle is no more ) stops the hammering / wear on the clutch basket , plates and the hub as well. If any one is interested I'll sort some pix and an explanation.
I bought and fitted a new clutch basket , plates (sureflex sintered bronze ) and hub . The rattle was still so loud that I felt there was no point in fitting them and off they came and the old stuff went back in , with the mod Image and as you can see my clutch plates are very worn , but yet no rattle. the wear visable all occured b4 the mod was done. The basket and hub are in similar condition
I wish I was young again............Id be heaps smarter than last time
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93IE
Posts: 110
Joined: Sat Apr 04, 2009 9:21 pm
model: 907 I.E.
year: 1993
Location: Georgetown, Texas

Re: clutches and coils

Post by 93IE »

I'm not opposed to the clutch jingle, but it has gone from sounding nice to obnoxious. I thinks this weekend I'll see if there is any dust in it. I do have a vented cover on it and have always like the noise the clutch makes, as that is one of the things that makes it a Duc.

Does anyone know for sure what the coil resistance should be. If not I guess I can check that this weekend also. I have planned to put a set of Dynas on it. I have planned a 1500 mile ride for April and am just wanting to eliminate any problems like old coils and old wires, and a little too much jingle.
Preston
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jpitz31
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year: 1990
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Re: clutches and coils

Post by jpitz31 »

Fraser wrote:Joe,

Clutch rattle is such a feature of Ducati that you need to share it. Hence the after-market clutch covers with all the cut-outs, holes, penetrations etc.
Let everyone hear it and share.

Fraser.
Yes Fraser,

That ching, ching ching noise is music to my ears. :mrgreen:

Joe
1990 Ducati 750 Sport (mine)
2007 Piaggio BV 500 (mine - daily driver)
2008 Piaggio MP3 500 (wife's)

My Ducati Blog site
http://projectducati.blogspot.com/

Stupidity is not a crime, your are free to go ;-)
Mc tool
paso grand pooh-bah
Posts: 1974
Joined: Wed Dec 05, 2007 12:35 am
model: 906 Paso
year: 1990
Location: Riverton New Zealand

Re: clutches and coils

Post by Mc tool »

My book sez that the primary winding should be . 34 ohm , which I thought was a typo and should be 3.4 ohm, so to be sure I measured the ones on my paso and they are both 0.4 ohm , so the book was right at 0.34 ohm ( +/- 10% ). before spending bulk $$ why dont you try the mod posted by others here ( think it was in higgy's webberology 101 .... not sure ) where a direct feed is run to the coils and magic box vai a relay ( similar to a head light relay setup ) ... solves a problem of low voltage to coils / magic box, well worth trying 1st , and only cost for a relay and a bit of wire
I wish I was young again............Id be heaps smarter than last time
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higgy
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Re: clutches and coils

Post by higgy »

Any coil in the 3 to 5 ohm range is safe. Anything less than 3 ohms will burn out your ignition module. Warwick has added a very detailed howto on coil related upgrades to our Weber doc. You can find the weber doc here in the documents section or here
http://mysite.verizon.net/vze2hw9t/index.html


higgy
Ducati,making mechanics out of riders since 1946
There's no problem so bad that a little fixing can't make it worse! : )
Electrocuted Birds Are Bursting Into Flames and Starting Wildfires :roll:
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Mc tool
paso grand pooh-bah
Posts: 1974
Joined: Wed Dec 05, 2007 12:35 am
model: 906 Paso
year: 1990
Location: Riverton New Zealand

Re: clutches and coils

Post by Mc tool »

beats me ! I have a 74 850T Guzzi which has had a point ignition sinse day one and has been very happy , but when I fitted a dyna ignition module both the ( 3.5ohm) coils and the module got real hot so I fitted a 1.6 ohm ballast resistor to each coil ( in series ) which improved things . I have sinse bought some dyna dc10-1 coils but havnt tried them yet. the only thing I can think of is that the dyna module must be powering the coils for longer ( in crankshaft degrees rotation ) than the points did .
I wish I was young again............Id be heaps smarter than last time
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samandkimberly
Posts: 149
Joined: Thu Apr 03, 2008 4:38 pm
model: 907 I.E.
year: 1993
Location: Boston, MA

Re: clutches and coils

Post by samandkimberly »

One thing I'd add RE the clutch it *don't* assemble per Barnett, assemble per the Ducati book, IE, start with a friction, then a steel, etc, all the way out. You may be short a friction plate, if this is the case use the first plate from your old set - if you have a OE Ducati plate this will be thicker than the others.

I think Barnett based their clutch instructions on newer Ducatis, which have a slightly different hub. The 907IE hub has a flange on it which keeps the first metal plate from engaging if there's no friction plate on the bottom.

If assembled as above you have the normal beloved Ducati rattle when you pull the clutch in, but it silences as soon as you release the clutch. This is the way it's supposed to be.

Sam
Mc tool
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Posts: 1974
Joined: Wed Dec 05, 2007 12:35 am
model: 906 Paso
year: 1990
Location: Riverton New Zealand

Re: clutches and coils

Post by Mc tool »

Putting a friction plate in 1st is the whole guts of the Quiet clutch mod . The hole in the centre of the friction plate ( fp ) is large enough to fit over the clutch hub and the tangs on the fp sit in the grooves in the clutch basket
Image
the whole idea is that the 1st fp sits further out than the hub ( by 1/2 mm) so that when the 1st steel plate is fitted it sits against the 1st fp , not the back of the hub .I bent the tangs on the 1st fp to get this measurement right
Image
When the clutch pack is assembled, spring pressure forces the pack against the 1st steel plate which pushes against the 1st fp , the tangs of which are now pushed into the bottom of the basket grooves thus binding the basket and hub together so no more rattle
Image
As you can see the 1st fp fits over the hub ,with the tangs in the basket grooves . An old clutch plate will do . If you bend the tangs to much the clutch will feel queer and will not completely disengage and if you dont bend em enought the rattle will still be there.
The broken spring posts are as a result of the prang , I think my foot must have been squashed ( It sure got squashed some how ) between the clutch cover and the car which pushed the cover in against the still rotating clutch , snapping all the posts off :mad:
I wish I was young again............Id be heaps smarter than last time
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jpitz31
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year: 1990
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Re: clutches and coils

Post by jpitz31 »

Sam and Mctool, Great instructions and pics of the quite mod. I will most definitely perform the mod when the clutch goes back together.

Cheers

Joe
1990 Ducati 750 Sport (mine)
2007 Piaggio BV 500 (mine - daily driver)
2008 Piaggio MP3 500 (wife's)

My Ducati Blog site
http://projectducati.blogspot.com/

Stupidity is not a crime, your are free to go ;-)
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