mattys281

How long is the part in that picture? Depending on how hard that part is you can probably just bore it out. You’d likely also have to face down the key that engages. As it would be too tall to fit in that end. That’s a lot more doable than screwing around with the crankshaft. i could probably modify that for you (depending on the hardness of the shaft), but can’t take responsibility for the engineering/integrity of it. It’d be work done per customer instructions. My shoot from the hip is that the shaft your holding is probably very soft compared to the crank journal it mounts to. It’s more desireable for that part to wear and be replaced than it is for the crank, plus a drive shaft that is too hard becomes brittle and will likely crack under torsion. Those types of parts are usually pretty soft to maintain toughness.

Pictures finally loaded on my phone after I already made my first response. I see now you want to reduce and lengthen the output? You might find a fab shop with a welder and o.d. Grinder or lathe with centers that can pull that off. For 5 hp it’s probably not that dangerous/critical, but I’d still think it’s worth talking to someone who specifically does custom bike work and get an opinion. Good luck with your project!

To lengthen the stroke you will need someone that has a crankshaft grinder. I’ve seen stuff where people rigged offset fixtures and did it on a lathe before, but to be done properly it needs to be ground. Crank journals are very high precision. I’d call a motorcycle shop and find out who does their engine machining, or try to get in touch with someone who’s into motorcycle racing that could recommend a good engine builder. If that’s not done properly the guy in the saddle will be sitting on a grenade. when I was younger I was into road racing motorcycles and trashed a couple engines while learning. Sometimes you get big dividends by just going to a pro right from the start.

Outstanding buck, congrats!

Dang! Nice work and helluva turn around. Congrats on your goat Jim!

20a ham hunt. I also plan to pick up a leftover archery tag in case I see one while deer hunting in January

Well.... if that's the best you can do, I guess it'll have to work....

Very nice. Congrats to her and welcome to the site.

Congrats!

Great pics as always. Thanks for sharing with us.

A couple outstanding bucks. Congrats to you guys!

How big is the ranch and is bowhunting allowed? Thanks

Wow, what a brute! Congrats!

Happy birthday!

Outstanding buck, congrats to him! really sucks about your knee. Hope you heal up quick.

Very very cool. Love seeing all the youth hunters being successful this year. Good stuff!

Looks like an outstanding hunt to me. Congrats to all involved!

Awesome! Congrats to him.

Nice work, congrats to him!

Wow! Breath taking. Congrats, that's an incredible accomplishment.

Congrats on your bull. Nice work!

That is too cool! Congrats to him, glad they both had fun.

Nice goat, he does look like he's been eating good up there. Congrats!

Very cool! Good luck guys.

What specs are you needing for the bow? I've got an older bow that's all set-up I could let go very reasonably. Diamond black ice, right hand 70# 29", has sights, arrow rest & stabilzer, just needs a quiver.