428 Countershaft Sprocket

[Bubba]

I am looking for a place who can make a couple of 428 pitch 13 tooth front sprockets for my team.

Would anyone else be interested in splitting a bulk order at Sprocket Specialists with us?

Do any teams own such a sprocket? or even a 15 teeth 428 sprocket?

Any help you could offer me is much appreciated.

[Bubba]

I am looking for a place who can make a couple of 428 pitch 13 tooth front sprockets for my team.

Would anyone else be interested in splitting a bulk order at Sprocket Specialists with us?

Do any teams own such a sprocket? or even a 15 teeth 428 sprocket?

Any help you could offer me is much appreciated.

[rjwoods77]

I used 15 tooth 428 sprockets from Sprocket Spec. on my baja car for 2 years. Its off a honda cr125r i think. part number 500-x. I bored out the spline and mounted them on a hub with bolts cause i didnt have the specs on the jap splines. Pain in the ass. Thing is carburized pretty good. The splined shaft would be on the small side if you did use it. You could just overcut the spline to a bigger one that is american spec if you feel. Cost 25 bucks a piece i believe.

[rjwoods77]

By the way. You guys arent that far from us. We should meet up later.

[Marshall Grice]

Which motor are you looking to get 428 sprockets for?

[rjwoods77]

Hey Bubba,
If this is for a cbr or any other 4 banger bike motor then all you have to get is the stock output spline of that motor cut into the sprocket. I think the 13 tooth would be too small but I know a 15 will work.

[Daves]

13 teeth are possible, but the strength may be compromised. Make sure you FEA the sprocket before ordering ones with 13 teeth. I know this because we have made a 10 tooth 525 sprocket, but we opted not to use it in the interest of reliability.

If you order 14 tooth sprockets, we at LeTourneau might be interested in buying (1) 14 tooth Honda CBR600F4i sprocket. What would the cost be?

[Bubba]

Thanks for the help Rob. What university are you from btw?

The 428 sprockets are to be mounted on a Honda f4i. I have been unable to find a copy of the exact spline and mounts for this engine so that I can CNC it out of a blank or some other sprocket that will work.

Yes we have come to realize that 13 teeth has performance benefits but the strength of the material has to be extremely high. It would also require very accurate heat treatment in order to get the correct transition through the sprocket's cross section. We are now leaning toward a 15 tooth sprocket on the countershaft.

[rjwoods77]

Univeristy of Buffalo. I am 15 minutes from the border bridge in Niagara Falls. Best strip joints on the this side of the continent are on the Canadian side. That 500-x sprocket is tough as hell. It wore the chain more than the chain wearing the sprocket. I dont know if you can recarburize the sprocket after it has been done once already. Go with the 15 tooth. Available so go for it.

[Jon Weir]

Phone up these guys, they only manufacture rear sprockets in house, but they can order some wacky sized drive sprockets. Prepare to wait 6-8 weeks though.

http://www.rebelgears.com/pages/787898/index.htm

[Bubba]

Thanks for the help. I've contacted a stack of places and am waiting on replies.

Hey Rob, there is a possibility that our teams could me up someday, well we'll at least meet up at the competition in May. And yes, the rippers around here are shweet.

Rebel gears looks promising. Do you know if they only take bulk orders though? I might have to wait til Monday to get a hold of someone over there.

[Jon Weir]

Don't know if they do bulk orders, but sprockets are pretty cheap.