swap options for s2r monster

[Ohm3d]

My 800 engine has died. Low compression due to rings and valve guides. I have been looking for a replacement engine and had no luck so far. I did however come across a lightly crashed but complete and running 848. I velieve the engine with physically fit, i know i will have to get creative with the wiring, and airbox. I also need to figure out a solution for the swing arm.

Option 1- use the s2r swing arm, retain pivot point and suspension geometry but not sure about the height adjuster

Optiion 2 - use the 848 swing arm and rear shock, will work with the 848 engine, but maybe not the s2r pivot point on the frame

Option 3 - part out both bike completely and buy a triumph speed triple

[Dirty Duc]

One of the problems you will have to overcome is the difference in the cross-bar near the airbox.  I believe the throttlebodies on a 4v will interfere with the crossmember as made for a 2v.

Look at the difference between a S4R frame


and a S2R frame


I also think (based on the S4RS) that the vertical head might require some shenanigans with the bottom of the gas tank.

I could be wrong, and welcome that possibility.

On a separate note, how much do you want for your dead engine?

[thorn14]

Don't go with the 4v. Find a nice used 1000DS (I tend to see them from multi's) for under $1500 and get a couple wiring bits and some headers along with an ECU reflash. It also fits directly, with possible swingarm fiddling.

Either that, or part out the s2r and build a working 848.

[Ohm3d]

Hmmm... i wonder about the crissmember...will have to look jnto that more. In terms of under tank space I actually have an s4rs tank on the bike currently, so that should work ok. At this point I am not looking to sell the 800 motor just yet.

I have been looking for a suitable ds 1000 and havent come up with anything yet. I am leary about buying a hugh mile ds1000 because i have found through research that they also have this same valve guide issue. If i found a decent low mile one, i wouldnt be looking at options.

I have considered rebuilding the 848 for a track bike, but need an entire new front end and frame... so thats a few thousand $ id rather not spend right now.

[Speeddog]

This is an 848 frame.

It has *no* crossmembers at all in the engine bay.

Main frame tubes are 6mm larger diameter to make up for that.



Given the amount of obvious work necessary to fit the 848 engine in, and factoring in the unknown work that is TBD.... I'd say don't do it.

Have you considered rebuilding/hotrodding your 800?
Cylinders/pistons/heads can all be removed with the engine still in the frame.

[Ohm3d]

Thanks for the pic. That is great reference.

I absolutely though about building the 800 motor up, but found that there is a definite point of diminishing return of investment. Building the motor with high comp pistons, headwork, and tuning. Best estimate was a return of around 85hp for around $7000.  For $7000 I can buy an s4rs that will outperform the hotrodded 800 any day of the week and likely be more reliable to boot. So basicly all id like to do with it is either get it running cheap and sell it, or swap it out

[Speeddog]

$7000 for hi-comps, headwork and tuning?

Say what?

[Dirty Duc]

I thought the consensus was that the 800 already had the equivalent of high-comps?

[thorn14]

The 800 has 10.5 compression from memory? I'd love some high comps for it, too bad there aren't any readily available.

[Dirty Duc]

That's what I was thinking.

[Raux]

have an ST4 motor for sale. still crossmember issue (it's been done before), but you could use your stock swingarm

[Ohm3d]

My estimate for building that motor stems from this http://www.ca-cycleworks.com/shop/heads/heads.html. After talking to chris and discovering they wanted $3500 for the heads alone I was a bit disappointed. Pistons are going to cost about $600, , its probably beneficial to freshen up the bottom end at the same time as it has 30,000 km on it, will also need the cyclinders honed $xxx? Plus assembly at $130/hr local shop rate plus some dyno time. I saw the costs snowballing out of.control and decided to go another route. Up here in canada we dont have the benefit of lots of experienced shops, so when yiu find one, you pay out the nose for their "experience"

[brad black]

plenty of 750ssie motors on ebay.  slot it in and piss it off.

[Speeddog]

If you want the finest cylinder heads that money can buy, then that's the route to go.

There's a lot of middle ground between that and what you've got now.

30,000 km on the bottom end?
If it's always had oil pressure, then there's nothing needed there.
I've had numerous 800 Monsters at that, and well beyond (21k miles, 30k miles, 55k miles!) not needing any bottom end work.
Other than clutch plates on the high miler, no bottom end issues.
Period.

No honing of cylinders needed.
If they're roached and need a replate, then yes.
But at 30k km, very very unlikely.

So it's pistons, refresh the heads and hotrod them to whatever budget you've got, and nail it back together.
PCIII and some dyno time, or a Microtec and a bit more dyno time , if you're feeling sporty.

It's not a $7k job.

[hackers2r]

As you're in Canada, have you tried MBPducati.ca? Martin knows his stuff but I don't know what his rate is.  May be worth giving him a call.