Anyone have a brand new sprocket that can be 3D scanned?

[M1Combat]

I'd rather keep the OEM design as well. I'm not too interested in trying to produce them myself but if we can get a good 3D scan of one that's brand new we'll have something to work from later. 3D printing is coming along in LEAPS AND BOUNDS. Who knows... maybe some day we will be able to 3D print them. I understand they would be "quite a test" of 3D printing tech at this point but maybe one day.

When that day comes.... We'll need a 3D model of it :). Failing the 3D printing maturing far enough... A 3D scan would allow us to approach someone with a better idea of exactly what we need.

[Doosh]

Not racing, don't need a few oz. less weight. Would rather have the drive train protection.

It's more like 5 lbs. That cush is ridiculously heavy.

I'm not sure what you are protecting, to be honest. I've been racing these bikes for years with direct drive and never had an issue.

[M1Combat]

But have you ever tried to put 150K miles on one with the direct drive?

[Doosh]

Lol, no. But have put more than 100 hours on one that way.

Its fine.

[1313]

The only dog I have in this fight is trying to keep my 1190RX on the road as long as feasibly possible, taking into consideration the unknown of EBR - and it being unable to provide replacement parts - at the present time. Below are some data points - feel free to draw whatever conclusion you feel comfortable ending up with.

Data to support Doosh (nice username, BTW...):
Pretty sure that all of the racebikes - even up to WSBK - had the direct drive front sprocket.

Data to support 'conventional thinking':
The PVM rear wheels used on those machines had cush drive.

Has anyone ever put serious brainpower to answer why NONE of the EBR racebikes used the OE EBR rear wheel and they ALL used the PVM rear wheel?

Like I said, feel free to draw your own conclusions (as I know what mine are as I do have a complete, brand new, unused 1190RX front sprocket with all the compensating parts as a back up - just in case)...

[Mike]

Doosh -

I've drag raced some form of car for most of my life. From 13 second to 7 second cars.
I know "exactly" what sudden shock can and DOES...to the surrounding parts.

I'll stick with the softer hit thanks..!

Mike

[M1Combat]

So... Now that that's taken care of...

How do we solve our problem?

3D scan and machining?

3D scan and hope 3D printing matures enough for a part like that (My guess... 6-10 years maybe?).

Design a new cush that can be mated to a non-cush front sprocket?

Find a way to re-engineer the sprockets we do have to replace the sprocket section?


How about the rubber parts? How long should they last?


I'm serious here. Lets figure this out. Personally I'm leaning to the last choice... We may be able to mill the old sprocket section off and replace just that section with a conventional sprocket. I'll have to take a look at one.

Any good ME's here ;) ?

[Doosh]

Data to support Doosh (nice username, BTW...):
Pretty sure that all of the racebikes - even up to WSBK - had the direct drive front sprocket.

Correct. And, all during the DSB era the 1125r bikes were run without cush on either end.

Data to support 'conventional thinking':
The PVM rear wheels used on those machines had cush drive.
Has anyone ever put serious brainpower to answer why NONE of the EBR racebikes used the OE EBR rear wheel and they ALL used the PVM rear wheel?

Faster/easier gearing changes.

[Doosh]

Doosh -
I've drag raced some form of car for most of my life. From 13 second to 7 second cars.
I know "exactly" what sudden shock can and DOES...to the surrounding parts.

1. Drag racing isn't road racing.

2. The clutch has a cush built in, btw. I think a lot of guys forget that. The chain and AL rear sprocket are quite a bit different than a rigid drive linkage, too. So, that all plays in.

The OEM sprocket is large, heavy and unusual. It's going to be a hard find, and when you DO find it, it's going to be expensive compared to a conventional sprocket. It has a needle bearing in it, for goodness sake. The size of the drive spokes makes it impractical to machine one (IMHO) meaning you are looking for cast parts now. Ugh.

So, keep the cush if you like. My bike will be back on the track using the race sprocket. After literally YEARS of racing these bikes, and having done so to the point motors are simply worn out, I can tell you the top end is what needs love, not the transmission.

The ordinary guy out riding the street trying to keep his bike isn't going to suffer motor damage during the service life of the vehicle dropping the cush. Chains and sprockets will wear a bit faster, for sure, but that tranny will be fine.

[M1Combat]

I'd prefer to find a solution to keep the cush drive. Do you have any ideas pointed in that direction Doosh?

I think most of us are smart enough to understand the benefits and drawbacks of a cush drive. You've decided you don't want one on your race bike. Fine. I've decided I want one on my street bike.

Willing to help?