Swinger and Frame modifications for a single sided engine block

stiglarsenDK

Seeking swinger modification inspiration for adaptations of a single sided swinger engine, more specifically a 916R aka 955 engine (NOS) i ended up with.

I'm thinking of having a special swinger (w bearings) made, and have talks w Metmachex just now, for the braced version i really think is cool ( I recognise the need for supporting the axel from the 93/94 frame / footpeg area... Thanks to dudlington for your inputs on this this option.
But: Is there ANY WAY around NOT welding attachments ... ? i.e bolt on brackets of some sort..(i have some conceptual ideas in mind, but nothing I'm really happy with so far)

Alternative is to butcher the 916R engine and donate all the sexy bits to a ST4 or S4 case w a 102mm bore job.... (that would be ranking as a capital crime in 91x circles im sure)

Any inputs here ?

nine16

Sell the 916 racing to someone who needs it and get yourself a more durable 996, or even a testastretta.

Ducal

Swap it for a 926

stiglarsenDK

Ducal wroteSwap it for a 926

and be 29ccm short ... Not an option! :-)

Mr.R

Hi Stig,

Here's my take on it...

Swap the internals into late model ST4 cases, turn down the barrel spigots down to 101mm and bore the cases to accept them.
You'll then have a stronger motor (C/cases) than the 916R.
Then sell the R C/cases to cover most of the outlay that the conversion has cost you.

Steve R

stiglarsenDK

nine16 wroteSell the 916 racing to someone who needs it and get yourself a more durable 996, or even a testastretta.

and be missing the drama waiting to happen with an 955 ... Not an option! :-)

I want that thing in there .. and will go for a frame mod/welding if no other option comes up..

stiglarsenDK

Mr.R wroteHi Stig, Here's my take on it... Swap the internals into late model ST4 cases, turn down the barrel spigots down to 101mm and bore the cases to accept them. You'll then have a stronger motor (C/cases) than the 916R. Then sell the R C/cases to cover most of the outlay that the conversion has cost you. Steve R

Thanks Steve.. i have thought of that as well, even breaking that engine would make me feel bad...
I have new ST4 cases, but from year 2000... and S4R case from 2001 coming in.. not sure if any difference on the cases .. yet as i havent seen the S4R's yet..

whats your insight to "late" St4 ... what years and possible differences. .

Mr.R

Hi Stig,

I've just been out to my workshop for a quick check on something for you.
I'm not sure if you're aware? But the swinging arm pivot in the C/case is 10mm lower in the single sided arm C/cases, than the double sided 851/888/ST4 etc items.
This's because the motor was rotated forward for the 916's.

I've long since lost the box with it's info'/label that my late model ST C/case came in, I'll pop out again shortly to see if I can decipher what year they were cast in.

Steve R

Mr.R

Back again,

My ST4 case have '03 casting marks and 510 03E stamped inside the alternator side, as this was done after they were painted I expect that it tells when they were machined.
They also have this part number cast into both halves :-

226.3.008.8C
GRIMECA D143.

They have one Allen screw coming in from either side of the cases between the "v" (earlier Desmoquatro motors have both fasteners coming in from the Left hand side) and accept the later type oil pump with it's integral pressure release valve. The old style pressure release valve that sits between the halves of the case isn't there, in it's place they've got the "Red" bolt fitted into the Left hand case that supplies the oil to the under the cylinder/piston oil jets for cooling pistons on both sides of the cases.
Earlier motors only have these oil jets in the Right hand case.

Steve R

stiglarsenDK

Mr.R wroteBack again, My ST4 case have '03 casting marks and 5.10.03 stamped inside the alternator side, as this was done after they were painted I expect that it tells when they were machined. They also have this part number cast into both halves :- 226.3.008.8C GRIMECA D143. They have one Allen screw coming in from either side of the cases between the "v" (earlier Desmoquatro motors have both fasteners coming in from the Left hand side) and accept the later type oil pump with it's integral pressure release valve. The old style pressure release valve that sits between the halves of the case isn't there, in it's place they've got the "Red" bolt fitted into the Left hand case that supplies the oil to the under the cylinder/piston oil jets for cooling pistons on both sides of the cases. Earlier motors only have these oil jets in the Right hand case. Steve R

Just checked

The ST4 has same markings like yours and allen bolts come from both sides... look quite beefy around the staybolts and main bearings ... could be target subject for receiving the organs from a ritual donation from the 916R engine..

I have noticed that the swinger hole is a bit lower... I wondered why and i did not know that the engine is tilted... (again another ducati workaround)

Ill check the incoming S4R cases (That is a 22520411A marked set)

Cheers

stiglarsenDK

seen on a monster project..

griff851

Mmmm, tricky set of wants you have there.
The issue is getting the frame to translate the spherical path load the SSSA generates from one side to the other. If you just waz in a SSSA the cases will snap at the rear engine mount. Probably right side first.
The vertical component is not too bad. Lucky the apex of the triangle is directly above the swing arm pin. So an extended pin with a clamp brace running vertical to a lug which fits in engine bolt frame well. A new engine bolt with a higher tensile strength 10.9 at least possibly 12.9 to get a higher shear strength. It would also have to clamp onto the horizontal section of triangle. The trick would be in the material and shape as it has to be equal to compression and expansion loads the 916 frame tubes have, but with an angle change.
The horizontal component is a little more difficult, the 916 pushes against the engine triangle for rigidity. There not a lot to push against going forward other than the 4 point joint which is along way away and messy to clamp on to, it would need an opposing support off strengthen foot peg mounts possibly.
Trying to make that is possible, but ugly as.
If you can do simultaneous quadratic equations it would help. It's just triangles and material load capabilities.
The other option is beefing up the cases with some serious welding, and that would be seriously ugly.
Personally I think what your looking at here is similar to those points in time when our little Italian mates went the single rail frame it's a no good for the twin, we need a cradle. Followed by, the cradle, it's a no good for the belt motor we need a trellis. The trellis frame it a need a modification for single side swing arm. Otherwise she not looka the beautiful eh!
I have a mate that modified a single frame with brace from the head stock to the rear engine mount to stop the head stock flexing. Functional as hell, ugly as sin.
Sorry just my 2 cents worth, and probably sod all help.

stiglarsenDK

griff851 wroteMmmm, tricky set of wants you have there. The issue is getting the frame to translate the spherical path load the SSSA generates from one side to the other. If you just waz in a SSSA the cases will snap at the rear engine mount. Probably right side first. The vertical component is not too bad. Lucky the apex of the triangle is directly above the swing arm pin. So an extended pin with a clamp brace running vertical to a lug which fits in engine bolt frame well. A new engine bolt with a higher tensile strength 10.9 at least possibly 12.9 to get a higher shear strength. It would also have to clamp onto the horizontal section of triangle. The trick would be in the material and shape as it has to be equal to compression and expansion loads the 916 frame tubes have, but with an angle change. The horizontal component is a little more difficult, the 916 pushes against the engine triangle for rigidity. There not a lot to push against going forward other than the 4 point joint which is along way away and messy to clamp on to, it would need an opposing support off strengthen foot peg mounts possibly. Trying to make that is possible, but ugly as. If you can do simultaneous quadratic equations it would help. It's just triangles and material load capabilities. The other option is beefing up the cases with some serious welding, and that would be seriously ugly. Personally I think what your looking at here is similar to those points in time when our little Italian mates went the single rail frame it's a no good for the twin, we need a cradle. Followed by, the cradle, it's a no good for the belt motor we need a trellis. The trellis frame it a need a modification for single side swing arm. Otherwise she not looka the beautiful eh! I have a mate that modified a single frame with brace from the head stock to the rear engine mount to stop the head stock flexing. Functional as hell, ugly as sin. Sorry just my 2 cents worth, and probably sod all help.

Thanks Griff... I know ill not find any easy solution here..

JSR29

Unless you have a 95-96 916Racing to put this 916R motor in, and your intentions is to maintain the 'originality there's no good reason to keep the original cases and not replace them with cases from a S4 or ST4 with the cylinder openings bored out. Then it'll bolt right in a 888 frame. Engine bolt size aside. If that's an original 916R motor from 1995 the cases are shit anyway.

ST4S or S4S (996) cases won't work.

Don't know if you are putting this motor in a racebike or a street bike but a 955 Corse engine is a fantastically entertaining engine on the track. In streetbike? Meh...
Power 6,700ish to 11,500+ Not fantastic below.2,000 rpm idle if you expect it to keep running. I figure you've already got the starter parts (all of them, not just the starter) and know that the the alternator will have a hard time on the street with lights and whatnot

JSR29

Oh, and BTW if the 955 has the magnesium alternator cover replace that when you change cases cause it'll rot out in a year or so exposure to coolant.

stiglarsenDK

JSR29 wroteUnless you have a 95-96 916Racing to put this 916R motor in, and your intentions is to maintain the 'originality there's no good reason to keep the original cases and not replace them with cases from a S4 or ST4 with the cylinder openings bored out. Then it'll bolt right in a 888 frame. Engine bolt size aside. If that's an original 916R motor from 1995 the cases are shit anyway. ST4S or S4S (996) cases won't work. Don't know if you are putting this motor in a racebike or a street bike but a 955 Corse engine is a fantastically entertaining engine on the track. In streetbike? Meh... Power 6,700ish to 11,500+ Not fantastic below.2,000 rpm idle if you expect it to keep running. I figure you've already got the starter parts (all of them, not just the starter) and know that the the alternator will have a hard time on the street with lights and whatnot

No 916 frame plans... Plan is to use it for a 888R 93' framed racer.. Cams G IN , 431 EX.. 31/37, HC pistons, etc etc... so yes should be quite a thrill on the track.
Thanks

stiglarsenDK

JSR29 wroteOh, and BTW if the 955 has the magnesium alternator cover replace that when you change cases cause it'll rot out in a year or so exposure to coolant.

No MG cover on the 916R 95 version

JSR29

stiglarsenDK wroteNo 916 frame plans... Plan is to use it for a 888R 93' framed racer.. Cams G IN , 431 EX.. 31/37, HC pistons, etc etc... so yes should be quite a thrill on the track. Thanks

It'll be fantastic! Exactly what I want for mine eventually.
The motor I had in my 916 Racebike back in the day.