<-=- Club Bevel Heaven -=->

I've got a 900 MHR-82.
I wonder if anyone have tried put in a modern (shellbearing type) crankshaft in a squrecase. I've seen roundcaseengines with 748 cranks. Which basically fits straight into the crankcases. One problem is the shaftlength for the alternatorside and another thing is the stroke. 66mm for the 916 and 74,4mm for the )900 bevel. Could be solved with a higher piston or a longer conrod.

I'd love to have information about this at Bo.Osterberg@bredband.net

I think 907/906 Paso has a 68mm stroke.

Dave.

BEVEL DAVE wrote:I think 907/906 Paso has a 68mm stroke.

Dave.

Yes that's a bit closer bout i want to know about people who have done somthing similair, with a standard 916 stroke.

Thanks hedton

hedton wrote: I wonder if anyone have tried put in a modern (shellbearing type) crankshaft in a squarecase. I've seen roundcase engines with 748 cranks.

My immediate reaction is that the lubrication system will need a lot of modification: roller bearing = low pressure, high volume; shell bearing = high pressure, low flow.

But it's not impossible and it has been done - changing to a plain bearing crank, that is. Go http://www.ducatimeccanica.com/kevin_race_engine.html.

Ciao

Craig

Craig in France wrote:

hedton wrote: I wonder if anyone have tried put in a modern (shellbearing type) crankshaft in a squarecase. I've seen roundcase engines with 748 cranks.

My immediate reaction is that the lubrication system will need a lot of modification: roller bearing = low pressure, high volume; shell bearing = high pressure, low flow.

But it's not impossible and it has been done - changing to a plain bearing crank, that is. Go http://www.ducatimeccanica.com/kevin_race_engine.html.

Ciao

Craig

Thanks alot. Du you recommened to stay with the shorter stroke and longer conrod or higher piston. Or a longer stroke?

Hedton

One to many dot's Craig

http://www.ducatimeccanica.com/kevin_race_engine.html

What are you trying to achieve as a finished product???

A race engine, a streeter, it all depends.

Dave.

Martin Mille / SSD wrote:One to many dot's Craig

http://www.ducatimeccanica.com/kevin_race_engine.html

Woops! Ta, Martin .

Ciao

Craig

hedton wrote: Du you recommened to stay with the shorter stroke and longer conrod or higher piston. Or a longer stroke?

Sorry, can't help you there - way beyond my engineering capabiliites ...

Ciao

Craig

The big question is why? The crank wouldn't be a drop-in installation.The oiling system would require modification to supply high pressure to the crank.The timing gear drive setup would need to be adapted along with the primary drive etc. If you have a fully equipped machine shop and the skills it could be done but would it be worth it? It would likely be easier to adapt the squarecase sidecovers and make some fake bevel tubes to glue to a beltdrive engine. Read Kevin Brackens article about building his engine to get an idea of what is involved Or try and find a Mille engine to start with.Treated properly a roller crank is just fine and pretty reliable.

Talk to Ron Young at Ron Young Enginering in Australia.
Ph/Fax 02 49 388097.

Ron has a lot of knowledge and experience in this particular field and will put you on the right track in your endeavour.

paulh wrote:Talk to Ron Young at Ron Young Enginering in Australia.
Ph/Fax 02 49 388097.

Ron has a lot of knowledge and experience in this particular field and will put you on the right track in your endeavour.

Thanks alot everybody.

Hedton