Topic: Driveline Questions

[Ford Boy]

I have an MTD mower with a Briggs 12hp motor/vertical shaft. I just took this out of an old Craftsman snowblower:






I plan on having the pulley vertical as well so it will line up with the motor pulley. My question is, can I run a centrifugal clutch on the motor shaft serving as the front pulley and run a chain to the rear pulley on the trans? Is there a centrifugal clutch that can hold a belt, not a chain?

[daddyracing]

Yes they do make them but I cant recall the name of them, its hard to find the clutch that can withstand over 13hp but you have a 12 so you should be fine. I bought one of those clutches though but I think I found mine on eBay for around $120

[Ford Boy]

so chain drive is the way to go?

[daddyracing]

I have seen it done both ways. But that is one of those things that is completely up to you. I personally like the traditional belt but sometimes the centrifugal clutch is a whole lot simpler... This is like the first one that pops up on eBay just to give you an idea.   http://m.ebay.com/itm/151010999945?nav=SEARCH

[Ford Boy]

Thank you for the info. As of now my plans are to move the engine back a few inches and fabricate the new trans up a few inches and run a chain.

[daddyracing]

Another thing I forgot to mention was with the centrifugal clutch you will have the liberty to change the springs so they will engage when you want. Comet clutches I believe have the best clutches and variety of springs

[Ford Boy]

Just to clarify, a cent. clutch can go right on the engine shaft granted it is the right bore size and this will engage when it reaches a certain rpm?

[daddyracing]

Yes

[Ford Boy]

it's a five speed with reverse and neutral. This mower is just a fun build, but my plan is to keep it in fifth for it's life.

[Huffy044]

Onr thought to keep in mind, as you move up in HP. On a 5 speed the gear set with 25 teeth on both the drive and the driven gears are the strongest, that usually 3rd. In 5th you go up on the drive gear (say 40 teeth0 and down on the driven (say 10). The smaller gear is weaker that the bigger gear. When in the 25 to 25, both have the same strength.