1123cc Big Bore Piston Kit for 1000DS

[Travman]

I'm thinking about having my local shop install some higher compression, larger pistons this winter.  They would also do some minor porting and valve seat work.  They say it will produce 10-15 hp more on top of where my bike is now & won't lose any of its current good nature (easy starting & good idle).  (Current bike is a M1000s with a Power Commander and termi pipes).  I really like my bike and this might be a bike that I hold on to for the long haul, but it would be nice to have a little more power at times.  The suspension is well sorted already and I love the look of the bike so I'm not looking to upgrade to the newer style yet.  

My question is why don't more people do this?  I've only seen 1 or two bikes with a 1078cc big bore kit on this forum over the years.  Upgrading to larger pistons and better flowing heads is so common in the HD world.  

[Ducatl]

My guess would be cost and/or they don't feel the need?

[jwoconnor]

How will it effect reliability. Harley motors are pretty stout and put out less power than ours, they can take some hop-ups. Personally, if I had been after big power I would have looked at something else.

[Speeddog]

One of my customers has a 1078 M1000, with a light flywheel.

Very perky! 

[NAKID]

How much is that going to run you?

[Spidey]

My question is why don't more people do this?  I've only seen 1 or two bikes with a 1078cc big bore kit on this forum over the years.  Upgrading to larger pistons and better flowing heads is so common in the HD world.  

Cuz it's not worth the money when you can buy the same model bike (same frame and largely the same look) with a liquid cooled beast of an engine.  For example, my not-remotely-stock M1000SS is pretty hopped up (your whole list plus more but w/o a big bore kit), but my housemate's '04 S4r with just an exhaust is faster.

[caperix]

I find it surprising that so few people do much internal engine work in the monster line.  You don't often hear people saying to just buy a bigger bike when some one asks about the 855 kits on the 748's.  If your just after the most amount of power you can get, a 2 valve bike isn't the best starting point, hell a ducati isn't the best starting point.  Looking at prices if you do your own disassembly/reassembly you can get the pistons and overbore for under $1K.  If you ultamatley want a 4 valve monster your better off putting that money towards it, but if you looking to keep your bike and just get more out of it go for big bore kit.  Just be sure to post before/after dyno charts  .

[junior varsity]

There are a lot of the older big Monsters - 900's with kits like this. There's the 944 kit which was...dare I say "common", and the 966 kit which was also available. Apparently, for the mild modders, perhaps faint of heart, there was a 924 kit as well.

So back in the day, you could make your 904 go up to a 924, 944, or 966 (964).
Markus is a member here who has a 966. I haven't really run across anybody who told me "don't do the 944 kit, reliability will suffer" - only "you are throwing money at the bike in the name of power, and you won't get much return on investment".

For me, I plan on doing the big bore kit on this bike and on another 900, just because its out there to do, and I don't find it will be a big problem. There's more heat generated, and with new (and also high compression) pistons, its a good idea to get the crank balanced (and why not knife edged and polished while we are at it). Might also consider some performance cams while you are doing some motor work - VeeTwo makes some and it would be a great time to drop 'em in if you are having the heads off for work.

At the same time, the big bore kit on a M1000 will likely make less power than the new M1100 motor, so you could just want to get one of those out of another bike that goes up for parting-out.

My last thought might be, with the expense paid for the engine work, it might be more cost effective to get an overall improvement (rather than simply an acceleration improvement from the motor) by getting a set of really lightweight wheels. Forged Magnesium or Carbon Fiber (BST, Dymag, etc).

[Duck-Stew]

At the same time, the big bore kit on a M1000 will likely make less power than the new M1100 motor, so you could just want to get one of those out of another bike that goes up for parting-out.

What makes you think this?

[junior varsity]

Doesn't the M1100 use an updated head design over the 1000? (Displacements would be the same, yes?)

Updated head design I am thinking about be in here: http://www.ducatinewstoday.com/2009/11/ducati-2010-new-models-what-we-know/ (at the bottom)

[Duck-Stew]

There's more than 100hp to be had out of a built DS motor that's for sure.

I'm guessing they revised port angle slightly and maybe put a slightly hotter cam in it.

Don't know as this is the first I've heard but I don't think they've fundamentally redesigned the head.

[Travman]

Has anybody heard about the Pistal DS 1123 pistons for the 1000DS engine? I wonder what the difference is between these pistons and the 1078 pistons other than the size.  Are there any additional complications or expenses?
http://www.ducshop.com/product_view.php?cat=6&pid=303

[junior varsity]

You could call 'em - Ducshop kicks ass. I've talked with Kai in the past.

[Speeddog]

I'd ask them about how thin the 'liner' spigot will be with a 100mm bore, specifically the durability in that.

DS1k is a 94mm bore, making a 992cc.
98mm bore gives 1079cc.
100mm bore gives 1123cc.

That's 6mm up on the bore, so 3mm thinner on the spigot.

My customer with the 1079 DS motor asked me about the 100mm pistons.
I said that, IMO, the spigot would be too thin.

But I've not built and run an 1123 motor.
Perhaps it's OK for a street motor.

[Travman]

Perhaps they combine the 1123 pistons with the new 100mm cylinders that are also listed on their site.  This is purely speculation.  I haven't looked into this yet.
http://www.ducshop.com/product_view.php?cat=6&pid=280