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Discussion Starter #1
Hi All,

I am planning a engine rebuild/upgrade for my '99 748. I plan on fitting a 916 crank, cylinders and pistons into my 748 engine to take it out to 916. I want a little more down low torque and the parts seem to be quite cheap to get a hold of.
The information I need is will a '95 916 crank fit into '99 748 cases, alternator gears, etc.

I have searched this site but could not find the specific info if the main bearing sizes, alternators, gears will will fit the cranks across the years.

Thanks in advance for any information that can be provided.

Ryno
 

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It will fit.. The 748 and 916 share the same case and most internals will fit straight across. BUT.. I´d go for a 854cc rebuild instead. a proper built 853cc/854cc will outdrag a stock 916, make roughly the same torque, but keep the high rev character of the 748. Doing a 916 rebuild will also require bigger valves to get the most from the diplacement. Givven the work needed, it would probably be cheaper and more reliable to buy a used/rebuilt 916 or 996 engine and bolt it into your existing chassie.

Here is a tech article on 748 to 850+cc upgrade if you decide to go that way.
853cc rebuild: http://www.sigmaperformance.com/748-853.html

The raceteam I´m apart of did a 999s engine transplant into a 748R chassie. Went without a hitch and the bike now makes 140+ rwhp.

//amullo
 

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A '95 916 has the single phase alternator and the '99 748 has (should have?) the 3 phase, I believe the crankshafts are different on the end where the alternator fits so you would need to use the '95 alternator which would require the '95-'98 crankcase covers and possibly the crankcase? not 100% sure on the details. A 996 crank would have the 3 phase alternator and the same stroke as a 916 but you wouldn't be able to use the cylinders as the stud spacing is different.

Agree with Amullo about just using the crank for an 853, otherwise probably cheaper (and certainly easier) just to buy a 916/996 engine.

:)
 

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I have a nice used 916 engine I'd sell cheap if interested.
 

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Do an engine swap. Less labour, thus less money and trouble. Straight bolt in, you could even keep your existing ECU etc by just swapping the EPROM. You should be able to get a 916 motor for 1000$ or less, a 996 motor for 1500 or less. 996 would retain your existing (better) charging system and give you some more power - 916s have, um, issues that you'll need to get used to. Might need the wiring harness as well though I'm not sure about that, there are sensor differences between pre 98 and post 98 models.
 

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Discussion Starter #6
Hey Thanks for the info, exactly what I was after!

I have considered the 996 engine swap and have found a couple of engines and still may go that way.

I am looking forward to doing an engine build as I have never had the chance to do a Ducati before and really like their "original" design and technology.

I have been pricing parts and the total to repair/rebuild mine is not that bad and I end up with a known quantity, where as buying an engine and bolting it in is kind of crossing your fingers unless I strip it first... then I'm back to square one. Thats why I was considering a crank swap, (found a 916 crank for $175) rebore my cylinders to fit 916 pistons then re-use my heads and do the eeprom swap. but if the crank wont fit my engine I won't worry about. But if I can find a 996 crank at the right price it could be an option for me to do a 916 build and still use my 3 phase charging system, cases, cylinders etc.

I am not looking for all out performance just a little more torque and a fresh motor to enjoy. I'm an ex R1 rider if I want big HP i'll get another R1. I first rode a 916 about 6 years ago after doing a bike swap with a friend for a 66km long winding road in the south of Western Australia once arriving in a town called Collie I got off the 916 with a smile from ear to ear and vowed to own a Ducati one day. That day has come at last. :D

Thanks for all the info.

Ryan
 

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I believe the left side of the 95 crank is different from your 99. You will have issues in the charging department.
Everyone else's here their idea of the 853cc motor is a good one, I've built two of them and they ran great, I think faster than a 916.

FYI...you cannot "just bore" the ducati cylinders, they are metal sprayed, and do not accept the standard boring. While this is possible you will need the correct materials sprayed back on. Quite expensive.
If you have your heart set on rebuilding a Duc, then try a 996, as they have the most bang for the buck, or rebuild you 748 into a 853
 

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Cylinders are, I believe, Nikasil coated so boring is not an easy option, not sure how cylinder heads transplant either.

I would think that the best bet is to buy a 916 or better still a 996 (or 998, but may bring many other issues?) engine, check/rebuild it as neccessary, get it fitted then sell your 748 engine to recoup some (most) of the cost, this way you have full use of your bike until transplant day - that's how I'd do it anyway.

:)
 

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I'm on the 748/853 kit. The shorter stroke of the 748 is pretty nice to have. Also doing a motor swap would remove your gear box ratios, which are also very nice.

My advice is simple; If you want more bite, do the following:

853 kit (pistons and sleeves) Duc Shop link
50mm full exhaust
PC3 and fully dyno tune.

With that upgrade, you should be putting out more power then a 916 and have all the perks/benefits of a 748 at the same time!



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Also doing a motor swap would remove your gear box ratios, which are also very nice.
How's that? 748 gearbox will bolt up to a 996 motor( the initial gearbox used in the early 748 was that out of the 996sps); lots of people use that as a way to get a tighter set of gears on the big boy engines.

To the OP, get the 853 kit, it is a more economical way to go (IMHO) given that you know the build, parts and labor; as you pointed out, unless you buy a motor firsthand, and are able to test compression and leakdown on the spot, you may be buying into an expensive headache.

Not only that, but the 853 buildup has been done and chronicled extensively which means that you'll have a wealth of information to draw from in order to optimize your setup/rebuild.

Best of luck.
 

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How's that? 748 gearbox will bolt up to a 996 motor( the initial gearbox used in the early 748 was that out of the 996sps); lots of people use that as a way to get a tighter set of gears on the big boy engines.
Well of course... but this discussion is about either swapping motors with a 916 OR upgrading a 748. Obviously if you're willing to split the cases, you can build any motor to any spec you want.



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Well of course... but this discussion is about either swapping motors with a 916 OR upgrading a 748. Obviously if you're willing to split the cases, you can build any motor to any spec you want.
Replacement motors don't usually come with the transmission; therefore, it would not matter if he got the 996 engine, because he'd reuse the 748 tranny. And getting a 916 engine would be a bad move, so realistically the options are either a 996 engine swap or an 853 kit.
 

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Discussion Starter #13
Hey a big thanks to everyone for sharing your knowledge!

I have been busy researching this further and with what you have all said and from what I have read I have decided if the internals of my 748 are still in good shape I will rebuild it, if any major components need replacing then a 996 will be going in. The 853 kit is too expensive, I can buy a complete 996 with everthing, rad, inj, ecu, harness, oil cooler etc for the cost of the 853 kit.

My initial thoughts were 916 crank rods and pistons which would mean no need for balancing and would make a cost effective stroker because I can source all those parts for under $500 and have some fun doing the build myself but I dont want to change the charging system so that has canned that. The 996 crank is not feasible because I cannot find one and it would need balancing to run the 916 pistons. The 853 kit is attractive but the 996 engine is more attractive :D

My questions have been answered, thankyou all.

Cheers

Ryan
 

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if any major components need replacing then a 996 will be going in.
Don't forget, the 996 has a different computer, throttle bodies and to make that work, a different wiring harness. Plus, you won't wanna use your stock 748 exhaust, so you'll be buying something else. If you can't afford the $1300 upgrade kit, buy a 748R motor like I did... spend the money to get it tuned properly and walk away with 108-110 rwhp and be happy. You can sell your stock 748 motor and recoop some money as well...

Replacement motors don't usually come with the transmission;
HUH? What? If you bought a "used" "replacement" motor off ebay or from a member on the forum, it wouldn't come with a tranny? Both motors I've bought had tranny's... ;)



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Just my .02 here; Do you like the reviness of the 748? If so, go the 853 BBkit. Thing is, if you found some 916 cylinders and pistons, buy them. That IS your 853 kit. With the extra capacity and the 748 chamber, you should end up with a pretty good compression ratio. I've seen 853's with no other mods, put out power very close to a 996. You would also benefit from the close ratio tranny.

You may have to weigh/modify the pistons to ensure balance, to play it safe. Also, while you have the heads off, you can play with them too(cams, porting?) for even more power. There are guys that have put SPS/R cams in their 748 and came out with some wheelie fun power. Time the stock cams and you can find yourself in the 105hp range. More to come with hotter cams/porting/whatever you want to do.

Who will be doing the work, BTW? This will also be a factor in making your decision, as you will get into the engine of the 758/853, but the 996 is drop in, without having to open it up.

The thing is you know your motor, it rockers, character, etc. With a 996 motor, you may buy into a set of bad rockers, etc. This means swapping out your rockers and reshimming the valves to spec. Point is, not so drop-in anymore and you will probably end up paying out the same amount of money, either way you go. Have fun.
 

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That IS your 853 kit.
I thought the pin/dome heights were different between 916 and 853 pistons due to stroke diff? A 916 piston would be 2mm too low for good squish, right?:confused:

Also could be balance issues with weight of the 916 slug vs. 748. Better to go with the Pistals that have wrist pins balanced to stock 748 piston mass.
 

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Discussion Starter #18
I will be doing all the work myself either way,

The 916 pistons cannot be used for an 853 kit because the crown hieght is lower than the 748 and 853 piston allowing for the extra stroke of the 916 crank, this would leave the engine with a low compression ratio. The 916 piston also has a different mass to the 748 piston.

This upgrade wasn't for all out power, ducati's aren't that kind of bike for me I'll get back on a R1 if I want that. The purpose of me researching the 916 crank and pistons was because I can get a hold of all the parts for under $500, had they fitted my '99 engine I would have had a real cheap upgrade to an engine I really enjoy riding (916), the parts dont fit so thats ended that.

I'm not interested in shelling out thousands for a 853 build, for me a 996 is a better option like I said I can get a full 996 set up everything for $1500 radiator, harness, ecu, injection, oil cooler, exhaust, the lot. Also I feel the 996 engine in my bike would add more value then a BB kit would, should I ever want to sell it to buy a 1098 :)

Thanks for your input

Ryan
 

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I will be doing all the work myself either way,

The 916 pistons cannot be used for an 853 kit because the crown hieght is lower than the 748 and 853 piston allowing for the extra stroke of the 916 crank, this would leave the engine with a low compression ratio. The 916 piston also has a different mass to the 748 piston.
Thats absolutely correct, you'd have to buy pistons, but you can use the 916 sleeves no problem.

So if your not looking for power, what are you looking for?



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Discussion Starter #20
Thats absolutely correct, you'd have to buy pistons, but you can use the 916 sleeves no problem.

So if your not looking for power, what are you looking for?
The purpose of this thread was to find out if a '95 crank would straight swap into a '99 engine. The good people of ducati.ms have informed me it won't.

I have to strip the engine regardless, so my thoughts were; while it was apart I could slot in a 916 crank, rods, pistons, and barrels which I can source very cheaply under 500, that would make a smart upgrade. Spending 1500+ just on a set of barrels and pistons to make an 853 doesn't return enough for the outlay, thats my opinon. So at this stage I am stripping my engine if its not to bad inside I'll rebuild it as a 748, if its a mess inside I will probably source another engine.

I never said i wasn't looking for power, if you read my comment it was "I'm not looking for all out power" in other words i'm not going to spend a stack of money on pistons, rods, crank, head work, cams, valves, TB's, exhaust, ecu programming, clutch etc etc because the list goes on and on and its not economical. A standard R1 will do 300 kmh out of the box thats 186mph a 748 ducati just isn't that bike, If I want massive power I'll get another R1. I want a ride that puts a smile on my face and thats what a ducati does every time.

Ryan
 
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