T-20 Output shaft lifespan?

[Rusty-Gunn]

Hi. I have a question regarding the output shaft's lifespan. Roughly how many times can these shafts be re-sprocked? I've read a few posts about removing the sprockets and new ones pressed on (tack welde as necessary). But I am curious how many times can this be done? Has anyone done this three times? Four times?
I ask because its cheaper to replace the sprockets than buying new shafts. Thanks.

[jpswift1]

I think Whipper would be the guy to talk to about this one.

[Rusty-Gunn]

I sent him a PM about sprockets earlier today. I'll have to ask him when he responds.

[whipper-ag]

[Mudd-Ox Inc.]

Hi. I have a question regarding the output shaft's lifespan. Roughly how many times can these shafts be re-sprocked? I've read a few posts about removing the sprockets and new ones pressed on (tack welde as necessary). But I am curious how many times can this be done? Has anyone done this three times? Four times?
I ask because its cheaper to replace the sprockets than buying new shafts. Thanks.

Unfortunately it is not recommended to replace a sprocket on a T-20 output shaft. The output shaft is machined with splines and the sprocket is machined with a tight tolerance and should only be pressed on. Any welding can weaken the output shaft. The splines on the output shaft hold the sprocket best on the first press fit. If you press off an old sprocket the splines are not as sharp and to size as when new.

I understand it is a added cost to purchase a new output shaft with sprocket rather than welding on a new sprocket on a old shaft but it is the safest and only way as a manufacture I can recommended.

Matt

[Rusty-Gunn]

Thanks Matt. No welding is recommended. Whipper told me in a PM he doesn't weld them either.
Newly made shafts have their sprockets pressed on. Easy to understand.
A few guys here say they have pressed on new replacement sprockets. As this saves some money. Easy to understand.
Whether it can be done many more times after, I figure it might depend on the shaft splines condition and if they might hold the sprockets tightly. A Machinist, like Whipper, might be able to bore a tighter sprocket hole for a tight fit. Maybe touch-up the splines. Costs begin to go up by this point.
Good discusdion. I enjoy learning things like this. Thanks.

Assuming I can buy spare sprockets, is it very differcult to press them back on? I have a friend who works for the City shop and can press them on. What else needs to be done before? Obviouly the worn sprocket needs to be removed. Clean the shaft. Inspect the splines. Check fit of new sprocket. Press on if it is tight. Like this?

[whipper-ag]

[Rusty-Gunn]

Thank you Whipper. Sounds easy enough. I do apreciate it.

[Rusty-Gunn]

According.to the Mudd-Ox/Max website these sprockets are discontinued. So ends the discussion. Thanks everyone.

[whipper-ag]

[amphibious drew]

Huh? How do you build a T-20 without them?

Whipper

Magic! lMAO

[msafi65]

Only available installed on the output shaft. Found out when ordering stock couple months ago. I'm down to 3 new ones.

[Model Citizen]

[George]

Glad I have a handful of spares.

[jpswift1]

So you have to throw away a possibly perfectly good shaft to replace a bad sprocket?

Bridget

That makes no sense at all. Why wouldn't the sprocket and output shaft be available separately?