[Iwannaduc]

I have a 1993 900 Super Sport that I purchased as a project. It is in rough shape both cosmetically and mechanically.

Save for the engine which seems to have been mostly well cared for. At least as far as the valve train goes.

I have the engine sitting on my work bench now and was sitting in my garage last night staring at it over a beer when I noticed something I hadn't before.

There is a stamped "V1" on the vertical cylinder next to the cam shaft cover. This is a stamp. Hand stamped with a die kit. It is not something done by a machine.

There is not such a stamp on the horizontal cylinder.

I contemplated that this could simply have been placed there to identify the vertical head during a disassembly at some point.

The more I thought about it though, the more I thought, nah, no way. Is it there for some other reason?

The question then is, was the stamp placed there at the factory or is there some other reason for it?

If anyone has any insight, or has seen such a thing before please post up. Thanks.......sean

 

[spacey]

I am not an expert and others can probably give you a definitive answer, but I believe there was a V1 and V2 version of the 900SS head. Do a search on the forum and you might come up with an answer.

 

[ducvet]

Yes the head stamp is a factory designation, I would expect both heads to have the same mark but it would not be impossible to have something changed over time or the head mismarked from the factory.

The V2 will designate the combustion chamber type as well as valve size and generation. Later heads were V3 and in the case of some 900 motors they had another version altogether that was essentially a 750 head made to 900 size (W heads). These started life on the elephants (as far as I remember) and then made their way to the mid 90's 900 monsters and finally the Cagiva grand canyon as a way probably for Ducati to dump off heads no one at Ducati wanted to use.

 

[belter]

v1 was the original 900 air cooled head. v2 signified better guides from memory according to falloon's book.

the w stamped head fitted to some 96ish and later m900 signifies the smaller valves.

all the heads - 2v and 4v - have some stamping, just as an indication of what is in them for production purposes.

 

[Iwannaduc]

Thanks for the replies. That answers all my questions. It would then appear that I have an original 900 air cooled head.

I presumed that the stamp would exist on both heads but was surprised when I found there was none on the horizontal.

Still, l know from the vin as well as the engine number that both check out as 1993 productions. The V1 on the head further verifies that. Seems every bit of this project yields some new information or discovery. Not always positive either.

Thanks again......sean

 

[ducvet]

:yeah:

I have seen no problem with those heads so it is more a matter of if you were lucky or not with the casting more than anything else. I did see much more hand work done at the factory on the early heads so someone at least tried to make it work , not porting but clean up. Do expect lots of rocker shims on some of the early heads as there was more hand fitting due to QC on machining. Does it have a exhaust port plug hole drilled/tapped and plugged on the heads?

I cannot think of any thing else different.

 

[Iwannaduc]

:yeah:I have seen no problem with those heads so it is more a matter of if you were lucky or not with the casting more than anything else

Does it have a exhaust port plug hole drilled/tapped and plugged on the heads?

I cannot think of any thing else different.

Honestly, I'd have to go out to the garage and check. I didn't look for one.

There are over 30K miles on the thing though, so just from what I've read the valve train should be pretty stable by now.

I can't tell you how many miles exactly...the cable was broken when I got it, and the drive housing is cracked.

Both of which suggest to me that at some point, the front was reinstalled without following the correct sequence following a tire change.

Thanks again for all the info.....I'll post a further reply once I take a look for that exhaust port plug........sean

 

[Iwannaduc]

I went out to the garage last night and gave the engine a visual once over. Did not see a bung or plug on the exhaust side of either the vertical or horizontal cylinder.

There is a threaded plug on each intake manifold, closest to the head end. I presumed that was for installation of vacuum lines for tuning/balancing the carbs though. If am incorrect in that presumption, please, by all means correct my mistake.....sean

 

[redpato]

I went out to the garage last night and gave the engine a visual once over. Did not see a bung or plug on the exhaust side of either the vertical or horizontal cylinder.

There is a threaded plug on each intake manifold, closest to the head end. I presumed that was for installation of vacuum lines for tuning/balancing the carbs though. If am incorrect in that presumption, please, by all means correct my mistake.....sean

On my 96 those ports on the intake manifold were for there charcoal cannister emissions equipment. I removed all that stuff and plugged the ports.

 

[ducvet]

On heads of some years you will see a cast in Boss on the left side of the head, it is about dime size and is in the fin area. some heads had this boss drilled all the way through into the exhaust port (not the chamber), the hole had a plug on the boss. I assume these were for emission testing and they later were using the ports in the exhaust pipe . Nothing good or bad just a variation.

 

[belter]

i think it was a swiss model thing, but i wouldn't have thought they'd go to the effort of air injection for one country, which is kind of the only reason i can see you'd have them.

i bought a new set of bare 750 heads that were labelled CH and they had them.

 

[Iwannaduc]

On heads of some years you will see a cast in Boss on the left side of the head, it is about dime size and is in the fin area. some heads had this boss drilled all the way through into the exhaust port (not the chamber), the hole had a plug on the boss. I assume these were for emission testing and they later were using the ports in the exhaust pipe . Nothing good or bad just a variation.

Mine does have the dime sized boss cast into the head, in the fins and near the exhaust outlet like you describe.

One more question, not really related, but does anyone have a tried and true method to remove the swing arm bearings?

I've read several methods and attempted them too. None have worked for me. I'm ready to just weld a nut to what remains of the outer of the two bearings and use a bolt through a big socket to draw it out.

I've destroyed 2 long punches already and all I've succeeded in doing is smashing the bearing and removing the needles. The race is still stuck fast and refuses to budge. I'm beginning to wonder if some sort of anerobic sealer was used on it.

Thank you guys for all the info...I appreciate you sharing your hard earned knowledge so freely.....sean

 

[belter]

heat the cases a lot and pull them out with some sort of puller.

if you've already gone medieval on them the eventual fix is to grind through the cage and collapse it.

it's not a fun job.

 

[steveb64]

heat the cases a lot and pull them out with some sort of puller.

if you've already gone medieval on them the eventual fix is to grind through the cage and collapse it.

it's not a fun job.

Been there, done that. A Dremel tool with a flex shaft, and several grinding stones will do the job nicely, with enough control to avoid chewing into bits you don't want removed. IIRC (it was a long tome ago) I smashed the cage out - then just had to grind a slit down one side of the outer shell.

 

[Iwannaduc]

heat the cases a lot and pull them out with some sort of puller.

if you've already gone medieval on them the eventual fix is to grind through the cage and collapse it.

it's not a fun job.

Already passed going medieval. Also, ground a diagonal slit across what remains of the race. Still refuses to budge. Nothing remains to grab onto to collapse the race. Hence my thought of welding a nut on. Between the heat from the welding, and a bolt through a large enough socket, I figure it could be drawn out that way. Maybe. It may simply fail like every other method I've tried so far.

I'll keep the dremel flex shaft in mind for the near future....but I'll probably try the welding the nut route first.....thanks for the tips....sean

 

[belter]

heat the cases a lot and pull them out with some sort of puller.

if you've already gone medieval on them the eventual fix is to grind through the cage and collapse it.

it's not a fun job.

probably got some terms a bit wrong.

smash out the cage, then grind through the outer sleeve and collapse it.

i would use a thin punch with an angle ground on one side only to try to pick the end of the sleeve up next to your ground groove and peel the sleeve off the case and push it into the centre. you get to the point where it's pretty hard to not mark the cases.

an expanding puller is the best option, mine goes on a slide hammer, although you could get it in there and hit from the other side equally as well. or some long hitting sticks - not sure of the technical term - drift? i have some that are hex at the hitting end end, but oval - well, more circular segment - at the other that allows you to get inside things. up to 30 odd " long. one of mine has a hook foot and cut away above the hook ground into it (by me) that allows me to get into the little slot in the wheel bearing spacers.

https://i.ytimg.com/vi/mACnDYAdY-o/maxresdefault.jpg

sort of like this: https://www.mactools.com/en-us/Stri...95-934f-a4b601755cca/Long-Taper-Drift-Punches

but you really need the heat.

 

[steveb64]

Already passed going medieval. Also, ground a diagonal slit across what remains of the race. Still refuses to budge. Nothing remains to grab onto to collapse the race. Hence my thought of welding a nut on. Between the heat from the welding, and a bolt through a large enough socket, I figure it could be drawn out that way. Maybe. It may simply fail like every other method I've tried so far.

I'll keep the dremel flex shaft in mind for the near future....but I'll probably try the welding the nut route first.....thanks for the tips....sean

You know there's TWO bearings on each side? Might complicate matters somewhat...

 

[bigbadbass2]

could a hydraulic press be employed?

 

[Iwannaduc]

You know there's TWO bearings on each side? Might complicate matters somewhat...

Yes, I'm well aware of both the bearings and the internal seals. It does complicate things a little...but only a little. I already have all the replacement bearings and seals. The problem is, when I smashed the cage, and removed all the bearings, the outer lip of the race broke off also. There is nothing left of it. Thus, nothing to grab onto.

could a hydraulic press be employed?

I've considered this, and while I have access to a large press that conveivably would work, and the assembled engine would fit into, I don't think it is practical. That's a lot of weight to hoist up and then try to balance. Also, have access to a porta power type hydraulic puller system. Something might be able to be made to work using that. I may revisit that in the future.

an expanding puller is the best option, mine goes on a slide hammer, although you could get it in there and hit from the other side equally as well. or some long hitting sticks - not sure of the technical term - drift? i have some that are hex at the hitting end end, but oval - well, more circular segment - at the other that allows you to get inside things. up to 30 odd " long.

I'd thought of ordering an internal puller set up that uses a slide hammer. I just think I'm beyond where that might be effective. On an undamaged bearing, I'm sure it would work fine. I just don't think I have enough left for one to be effective now.

I started with a long drift. Then I moved to some long punches. I ended up destroying the bearing with the long punches and distorted them while I was at it. I didn't get the outer bearing on either side to budge so much as a single mm. I also tried using a dremel grinder to cut a slit in the remaining race and peel or collapse it to get it out. Got no where. Hence why I posted the question.

I'm afraid I'm down to the weld a nut on option. I'll try that as soon as I get time to get back into the garage and attempt it. I'll fire up my torch too and get some heat going to make it an easier task. If any anaerbic sealer was used, that should be enough to melt it as well as expand the case to make more room.........sean

 

[steveb64]

Yes, I'm well aware of both the bearings and the internal seals. It does complicate things a little...but only a little. I already have all the replacement bearings and seals. The problem is, when I smashed the cage, and removed all the bearings, the outer lip of the race broke off also. There is nothing left of it. Thus, nothing to grab onto.

Just checking. If I were you (and I've been there), I'd go back to the Dremel tool grinding option. Once I had enough of the bearing outer ground away, I was able to bend and distort it enough that I could get some purchase on it, and drag it out. The first bearing was reasonably easy, as I was able to grind through the entire casing, but the second one was a little more difficult, as grinding through the rear of the casing wasn't an option due to the alloy proximity - but brute force and ignorance won out. Then after I had replaced all the bearings, and refitted the swingarm - and checked it - and the same play was still there (that the bike shop had told me was stuffed swingarm bearings). Turned out that when they had done some work on it, they'd omitted one (or more) of the swingarm shims. Reshimmed with some bits I found in my mates granddads garage - and no more play. <sigh>