wanted 350 widecase head

[hobby]

Dear all,
I am looking for a head for my 350 widecase Desmo engine. The existing one has been butchered by the prvious owner and is not repareable. I understand that the 250 head is the same as the 350 model. It does not have to be a Desmo head and can be a springer as I will be using it for road use only. I would like a good condition one either complete otherwise I can buy the internals new.
Kind Regards
Paul

[DewCatTea-Bob]

____ Welcome to our growing register of listed w.site members here, Paul !
__ I wonder if you've yet read-through our guide-line rules ? ...



" I am looking for a head for my 350 widecase Desmo engine."

____ One of the suggested guide-lines is to not specifically use this forum-section of the w.site to list items for-sale or for want-ads, (at least not in such a straight-forward manor). _ As there is a separate dedicated classified-section for doing so.
__ However if your want/need is not such a PARTICULAR specific-desire, then you could simply mention your desired 'want', in passing, while making the main-jest of your post (in this forum-section) concerning a related topic that's suitable for a forum-thread.
And fortunately you've already seemingly somewhat done so, (probably inadvertently), when you also brought-up the related matter below. _ (But your chosen thread-title is not properly consistent.)
__ Anyhow,, I'm fairly interested in your Duke-project, and hope to follow along-with you on it (engine wise).


" I understand that the 250 head is the same as the 350 model."

____ Actually, there IS a slight difference ! ...
The squish-band width is 1mm less on a 350 due to the 350's 2mm larger bore-size.
However whenever a 250 or 350 cyl.head was ordered, they would send ya a 250-head,, so apparently it was expected to work okay well enough on a 350, and so-thus you could also use a 250-head without concern.
__ Also, a narrow-case 350-cyl.head will fit & work as well ! _ The only differences (in the head itself) is the intake-port & valve-seat sizes.


" I would like a good condition one either complete "

____ I happen to have spare of either such, but I'm really not very interested in shipping (outside of the U.S.).


Good-Luck,
DCT-Bob

[Single duck]

Hi Paul,

Rather than me lecture you on site etiquette I have 2 questions to ask:
Where in the world are you?
How much are you prepared to pay?

I have a new old stock bare casting, untouched by the passage of time, 350 non desmo cylinder head and I AM prepared to ship wherever you want - for the right price.

PM me and I can get some pics to you if required.

Thanks

[DewCatTea-Bob]

" Rather than me lecture you on site etiquette "

____ Such as you-yourself Howard, really don't have as much cause to feel the need to do anything of the kind, as YOU're not a registered 'moderator' here (as I-myself am).
So I-myself sometimes bother to mention such added details for the sake of ALL -(otherwise I would've personally PMed Paul, if any need had been felt to merely address him specifically).



" I have a new old stock bare casting,
350 non desmo cylinder head "

____ What a RARE coincidence, as I also have such a NOS bare-cyl.head ! _ I had assumed that I was likely the only one left with such. ...
__ Back in 1974, I wanted a cylinder-head just like the quite unique one which came on 1973 Mototrans 350-Road models,, however the unit I ordered & received was actually a n-c.type/250Mach-I cyl.head. (which I then perceived as inferior to that which I really wanted), so I sent it back (as not being the 350-head I had ordered),, and then-next I received another bare-head (which I still have), that still wasn't the particular head-model which I specifically desired. _ So Berliner then-next looked-through their entire stock of differing cyl.heads and didn't have (nor apparently could get) the unique head I wanted, (as they all unfortunately share the very-same part-number !),, so I was stuck-with what I had last gotten...
It's a 250/350 wide-case springer-head which is of the newer-type cast after the DESMO-head casting became produced. - (They are unique in that they APPEAR to be made to accept a 'DESMO' camshaft-bearing support-cover, (however such doesn't actually fit-in without slight modification).
__ If ya've ever heard-tale of buyers being duped into buying a Duke which was supposed to be an authentic DESMO-model, but actually turned-out to be a 'fake',, then it was with a springer-model Duke-engine with one of such of these particular type cyl.head-castings.
__ Since I've had a specific Duke-project for this cyl.head of mine, I'd thus have to be offered a pretty-penny to part with it.
What does anyone-else here think that such ought to be worth ?


Duke-Cheers,
-Bob

[JimF]

When a new member comes on board I lean toward giving him a little room to stretch his legs and then settle in.


As a group we generally put such things in the 'parts for sale' area but here we had a case of "part wanted" and Paul may have figured the main board was the correct place to post and he may not have been entirely wrong.


I know that when I join a forum it's because I need immediate help, and my problems are always urgent as far as I am concerned - so I myself don't read any rules but instead post my plight and only then do I settle in and get get used to the protocol.


It's all good Paul, and I hope you get the cylinder head you need. Welcome to the forum.


Jim

[DewCatTea-Bob]

____ Naturally I certainly agree with all of Jim's stated good-sense reasoning.
However the only reason I'm now responding, is to clarify that in no way was I meaning to lecture (or anything near the sort) solely at new-member Paul specifically, nor even just-merely purposely hint that he might've actually done anything incorrectly ! _ But rather, I had merely-just meant to somewhat indirectly 'bring-up' that related rule-guidelines do exist, (so as to merely help curtail any further/more-obvious disarray possibly considered by ANYONE here).
That's all.


Cheerful-Cheers,
-Bob

[hobby]

Gents
It was with regret that I noticed after I just posted this request that you have a spare parts section. Then it was too late. So next time I will follow the rules.
Paul

[DewCatTea-Bob]

" So next time I will follow the rules. "

____ Dear Paul,, it seems that my preempt-attempt at preventing a mountain from being made out of a molehill, has somehow failed... As you've STILL reacted in the manor which you have, ANYHOW.
Please understand that you-yourself have not actually blatantly overstepped any 'rules' ! ...
__ I would've expected that Jim's post had totally cleared-up any concern for you.
It was my-own interpretation (of our suggested w.site guide-lines) which had led me to lightly apply the brakes here, NOT specifically for just YOUR-own enlightenment, but rather primarily to remind all fellow-members that our forum-section is to be PRIMARILY for "Ducati talk"/ 'discussion', and rather-not for BASIC want-ads.
__ I-myself think that EVERY member ought to let their DESPERATE Duke-part needs be known of, in THIS most-popular section of our w.site ! _ BUT our forum-readers ought not ever be subjected to BARE want-ad type posts. _ Thus whatever your need/want, ya ought to tell of the story behind your wanted part desire, so that it's of rather pertinent interest for our 'forum' section readers.
And YOU had actually done just that !
It was only your specifically-chosen 'thread-title' that was cause for any concern,, and-so I saw fit to make some mention of it, so as to hopefully curtail others from doing same.
That's all !
__ So if you (or anyone-else) have an URGENT need for any Duke-part, then be sure to post something about it, here in this forum-section,, but just don't post it merely as an ordinary raw-type 'want-ad', and somewhat disguise it to be fairly legitimate for 'forum' discussion, (pretty-much just as was done [except for the chosen thread-title wording] ).


Hopeful-Cheers,
-Bob
_

[LaceyDucati]

Hello Bob
I would like to correct you regarding Ducati 250/350 heads. As your experience may well be mostly with Narrowcase models, this is where you may have been misled.
Leaving aside port and valve sizes all Italian Narrowcase 250 have a head diameter to the edge of the squish of 74mm and a squish angle of 45 degrees. The 350 Sebring has a head diameter of 76mm and a squish angle of 40 degrees. You are obviously correct in that the sebring squish is approximately 1mm wider and as far as Narrowcase heads go, you are correct in what you say. However with all Italian widecase models all the 250 & 350 heads are 74mm with a squish angle of 45 degrees therefore 250 and 350 widecase heads are identical. The factory obviously did this for interchangeability and got around the mismatch of bore to head by adding a flat step around the edge of the 350 widecase piston. It's a bit of a fudge and is fine for road bikes but I prefer to convert 350 race engines to the 40 degree sebring arrangement to allow for a more satisfactory setting of a tight squish clearance. 250 and 350 desmo head are also the same item and the 74mm and 45 degree squish also applies.


For identification: All narrowcase heads have a gasket face surface that the cam end cap sits on similar shape to the cap, with cast in recesses either side of the scallops of the cap. All Italian Widecase models are slab sided across this face.


Moving on to widecase Spanish heads, these revert to a cam end cap face on the head as per the narrowcase bikes. The Widecase Spanish 250 is 74mm or 75mm and 350 76mm or 77mm, I am sure Jon Pegler could firm up these dimension. Spanish 250 Narrowcase models are of course 66mm. The Spanish heads however are easily identified by the little vertical fins above the exhaust port. The Italian heads have fins that stand about 1/4" high whereas the Spanish heads have fins that stand about 1/2" high. A lot of the widecase Spanish heads are particularly poorly cast as far as the ports are concerned and quite often the back face of the seat can be clearly seen in the exhaust port. This for most road bike does not present a problem but for race use I usually avoid these heads like the plague as the sharp / poor turn at the bottom of the port cannot be easily overcome and leads to poor flow. Obviously as well from an engineering point of view unsupported seat at the back is not a great idea. With the seat having less contact with the aluminium, and more exposure to the flame on the exhaust port, it will lead to poor heat dissipation on the seat.

I only mention these last details of Spanish heads as most of the NOS heads that I have seen in the UK and Italy have been Spanish widecase heads. I have had them myself and they have had particularly poor ports and I suspect they were found in a back room in the Mototrans factory when they cleared it out! A lot of other NOS Mototrans stuff should also be approached with caution. I guess if the head you have Bob is from the states, it will almost certainly be an Italian head so this warning probably does not apply to you.

The only caution I would give for swapping heads about is to not use a 350 Sebring 40 degree head in conjunction with a 45 degree piston if you intend to run a tight squish. I would also advise checking piston to head clearance over the whole squish area if you do end up running this combination whatever.

Hope this helps with identification, I do speak with many years of experience of having to figure out all these differences and I have not found any exceptions to these rules. However after many years of use it's not unusual to see narrowcase heads on widecase bikes and vice versa.
Best Wishes
Nigel

[LaceyDucati]

Hi Paul,
Most heads are repairable within reason, just a matter of weighing up the cost against finding a replacement and all the contents. What is damaged on your head? Losing a Desmo head is no great shakes and in the real world give me a spring valve head any day. But it will have a big effect on the value of the bike if it's otherwise original. This of course may be of no concern to you. Also be aware of the differences in the various heads and the differences in performance that they will have, when you are selecting a replacement. If you want to post any pictures or send me any, I would be happy to give you my opinion.
Best Wishes Nigel