Hi Malcolm Did you not stay to hear DAG Brown after the the SBA AGM. I would look first at his book/designs Mike Sadly Mike, we had to leave because the cold I had given Lou was clearly taking hold! - we do have his book, but the designs are much smaller and aimed at the 100psig range from memory..

I am contemplating building an injector for Befur with a friend of mine who has successfully made a number of smaller (model engineering size) injectors....

The question is are there designs/specs for Steam Launch size HP (250psi) injectors around???

Thanks

M

Ah but the difference between the H-D and the Honda begins a long way before the belt drive

Guys even more good advice! I will bear all this in mind as we iterate towards a final solution - one thing in my favour is that the Cabin is at the other end of the boat to the engine/drive arrangements, so WRT what PeteThePen1 said So my advice would be not to busily build you cabin and then think...

Thanks everyone, that was really useful - I have a month or 3 of woodwork building the cabin/decks/lockers etc., then it will be time to make my final decisions on the plant! I think I might go with the belt drive for reasons of introducing a bit more flexibility in engine position and future proofi...

barts wrote:Remember to employ service factors suitable for a multi-cylinder gas engine; this will help compensate for the variation of turning effort w/ crankshaft position.

- Bart

Yup, I went for "engines with less than 4 cylinders" when choosing the load factor...

Quote: "Do either of you have thoughts on dog-clutch arrangements." Do you mean a Lovejoy or spider coupling? Or some sort of clutch that allows the drive to be disengaged? - I mean a clutch to allow disengagement. Mounting the engine off to the side and running a belt over is not a simple set up. ...

Malcolm, you cannot decide on a belt width until you know the pulley diameters as this influences the torque transmitted. I use a 30mm belt on 64 tooth pulleys on Grayling which is about 5 IHP. Regards Jack Yes, I understand, I did my computation on the basis of 28-tooth wheels.... as you suggest l...

thanks Fred...

...OK re-ran the numbers at 350rpm and (if my understanding of the process is right) then this pushes it just over the 20mm width. Bearing Boys seem to do 30mm and 50mm width taperloc pulleys in 8mm HTD so I think it's 30mm...

thanks again...